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ArticleMarch 29, 2023

Efficient Photocatalytic Degradation of Methylene Blue Dye from Aqueous Solution with Cerium Oxide Nanoparticles and Graphene Oxide-Doped Polyacrylamide
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Zeynep Kalaycıoğlu
Zeynep Kalaycıoğlu
Department of Chemistry, Faculty of Science and Letters, Istanbul Technical University, Maslak, Istanbul 34469, Turkey
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https://orcid.org/0000-0002-0967-0997
Bengü Özuğur Uysal
Bengü Özuğur Uysal
Faculty of Engineering and Natural Sciences, Kadir Has University, Cibali, Fatih, Istanbul 34083, Turkey
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Önder Pekcan
Önder Pekcan
Faculty of Engineering and Natural Sciences, Kadir Has University, Cibali, Fatih, Istanbul 34083, Turkey
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F. Bedia Erim*
F. Bedia Erim
Department of Chemistry, Faculty of Science and Letters, Istanbul Technical University, Maslak, Istanbul 34469, Turkey
*Email: [email protected]
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https://orcid.org/0000-0001-9406-6681

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ACS Omega

Cite this: ACS Omega 2023, 8, 14, 13004–13015

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https://doi.org/10.1021/acsomega.3c00198

Published March 29, 2023

CC-BY 4.0 .

Abstract

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A cerium oxide nanoparticles (CeO₂-NPs)/graphene oxide (GO)/polyacrylamide (PAM) ternary composite was synthesized through free-radical polymerization of acrylamide in the presence of CeO₂ nanoparticles and GO in an aqueous system. The synthesized composite material was characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX) spectroscopy techniques and applied for the photocatalytic degradation of methylene blue (MB) dye from an aqueous solution. Tauc’s model for direct transition was used to model for the optical band gap. The key operating parameters such as the amounts of CeO₂-NPs and GO, pH, initial MB concentration, type of light irradiation, and contact time have been optimized to achieve the highest MB degradation percentage. The photocatalysis process was pH-dependent, and the optimum pH value was found to be 12.0. Under UV-A light, 90% dye degradation occurred in 90 min. The degradation of MB was also specified in terms of total organic carbon (TOC) and chemical oxygen demand (COD). Free-radical capture experiments were also performed to determine the role of radical species during the photocatalytic oxidation process. The photocatalytic process showed that the equilibrium data is in good agreement with the Langmuir–Hinshelwood kinetic model. A rate constant of 0.0259 min^–1 was obtained. The hydrogel was also tested to assess its reusability, which is an important key factor in practical wastewater treatment. The photocatalytic activity only decreased to 75% after nine uses.

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1. Introduction

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The contamination of water by dyes has been a crucial issue that occupies the world agenda and has an important place in all plans for the future. (1,2) The increasing amount of these dyes in water causes irreversible harm to aquatic life and indirectly to other living things, organisms, and even humans that depend on them in the life cycle. (3) The use of reactive dyes has been increasing in various industries. Advanced oxidation technologies (AOTs) have gained importance to remove dyes from water. (4) The leading one among these techniques is the degradation of dyes by a photochemical process in in situ generating an oxidizing agent in water. (5,6) Degradation of dyes with the photocatalytic process has several advantages over other methods. The existing conventional methods (i.e., adsorption and chemical coagulation) require further treatment since they convert the dyes from the liquid to the solid phase. Photocatalysis degrades pollutants almost completely, and no secondary pollution occurs. In this regard, the photocatalysis process appears to be more eco-friendly.

Methylene blue (MB) is one of the most widely used industrial dyes; as a result, it is the most common dye in the literature to test the performance of newly developed adsorbent materials. One can effectively eliminate MB from wastewater by utilizing the water-holding capacity, swelling, and adsorption abilities of hydrogels. (7−9) However, as the hydrogel absorbs water and swells during wastewater treatment, it becomes more elastic, leading to a lower mechanical strength, which is undesirable for the remediation of dye-contaminated water and repeatability. Fortunately, it has proven possible to increase the strength of the hydrogel when incorporated with nanofillers such as metal oxide nanoparticles, nanoclay, carbon nanotubes, and recently graphene. (10−19) Nanofiller materials with large surface areas not only provide high strength to the new composite when combined with hydrogels (20) but also enable it to exhibit adsorption abilities on the surface and interior, facilitating the entry of contaminants into the hydrogel. The resulting composite material not only has superior adsorption and dye removal properties but also shows improved properties by forming a stable state and helping regeneration.

CeO₂-NPs have attracted much attention due to their unique properties. The oxidation state transition between Ce³⁺ and Ce⁴⁺ found on the surface of CeO₂-NPs is responsible for the catalytic activity of this nanoparticle. Although the toxicity of nanoparticles is still a questionable issue, it has been shown by experiments that CeO₂-NPs are not toxic, (21) and these nanoparticles are compatible with hydrogels and impart durability and antibacterial properties to wound-healing hydrogels and anticorrosive properties to paints. (22−24) In addition, it has been shown that CeO₂ nanoparticles synthesized by the green method gain additional and different surface properties. (25,26) The effective use of CeO₂-NPs obtained by the green method in dye photodegradation has been lately demonstrated. (26)

In this study, a polyacrylamide (PAM) hydrogel was chosen among the hydrogels because of its synthetic nature with high water uptake capacity and hydrophilicity. PAM forms a soft gel when hydrated. Among the nanofiller materials, cerium oxide nanoparticles (CeO₂-NPs) and graphene oxide (GO) were chosen in the study with the thought that they would be the best candidates to improve dye affinity and photodegradation. (27) Since it is difficult to remove metal oxide and graphene oxide from the pollutant medium, the polyacrylamide hydrogel allows to keep them together. Active dye photodegradation of CeO₂-NPs, (23) WO₃/CeO₂, and Fe₃O₄–CeO₂-mixed NPs (28,29) has been reported. Lately, a review on the photocatalytic degradation of various pollutants with a CeO₂ semiconductor as a photocatalyst was reported. (30) On the other hand, GO is a material with a wide range of applications due to its remarkable properties such as mechanical and thermal strength and electrical conductivity. (31) Photocatalytic applications of GO also draw attention due to its easily tunable band gap. (31) It has been reported that GO increases the photocatalytic effect of CeO₂. (32) A recent review article demonstrates the photocatalytic applications of GO–CeO₂ composites. (33) Stable photocatalyst materials can be obtained by incorporating photocatalytic NPs into hydrogels, eliminating the problem of nanoparticle aggregation in water and particle recovery from water. Moztahida and Lee examined the photocatalytic degradation of MB with a PAM/GO-containing composite and stated that no toxicity from PAM and GO was detected as a result of the toxicity analysis. (34) Some studies have reported that NPs added into PAM provided dye photodegradation, (34−36) but we could not find a study of PAM hydrogels in which CeO₂-NPs were added and used as photocatalysts.

In this study, a ternary polymer composite structure was successfully prepared by first doping CeO₂-NPs into the PAM hydrogel and then adding graphene oxide (GO), which is an electron transfer material, into the CeO₂-NP-incorporated PAM hydrogel. The goal of this study is to propose a simple and efficient photocatalytic degradation of MB dye in water with the CeO₂-NPs/GO/PAM composite hydrogel. The impact of operational factors such as the initial concentration of acrylamide, photocatalyst dose, pH, type of light irradiation, irradiation time, and concentration of dye was evaluated. Comparative experiments were also performed to better understand the combination of GO and CeO₂-NPs under the same conditions. Consecutive cycle studies were used to assess the reusability of the photocatalyst.

2. Experimental Section

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2.1. Chemicals

N,N′-Methylenebisacrylamide (MBA), N,N,N′,N′-tetramethyl ethylenediamine (TEMED), ammonium persulfate (APS), graphene oxide (GO) (2 mg mL^–1, dispersion in H₂O), and cerium (IV) oxide (<25 nm) nanoparticles (CeO₂-NPs) were purchased from Sigma-Aldrich (St. Louis, MO). Methylene blue (MB) and acrylamide (AA) were obtained from Merck (Darmstadt, Germany). Solutions were prepared using deionized water purified using an Elga Purelab Option-7-15 model system (Elga, U.K.).

2.2. Preparation of CeO₂-NPs and GO-Doped PAM Hydrogels

Initially, CeO₂-NPs (2.5 mg) were added to 5 mL of distilled water and sonicated for 10 min to disperse them. Thereafter, GO (300 μL) was poured into the dispersion and stirred for 1 h to ensure homogeneity. Finally, CeO₂-NPs/GO/PAM composite hydrogels were prepared by free-radical copolymerization as follows: 500 mg of AA, 10 mg of MBA, 8 mg of APS, and 2 μL of TEMED (0.775 g/mL) were dissolved in the homogeneous suspension of CeO₂-NPs/GO by stirring at 200 rpm for 15 min. The prepared CeO₂-NPs/GO/PAM composite was dried at 80 °C. PAM hydrogels were also prepared alone without CeO₂-NPs and GO for comparison purposes through the same procedure described above.

The synthesis of the CeO₂-NPs/GO/PAM hydrogel is depicted in Figure 1.

Figure 1. Synthesis diagram of the CeO₂-NPs/GO/PAM hydrogel.

2.3. Characterization of the CeO₂-NPs/GO/PAM Hydrogel

The structural properties of the CeO₂-NPs/GO/PAM hydrogel were analyzed by Fourier transform infrared (FTIR) spectroscopy using a single reflectance ATR cell by accumulating 64 scans with a resolution of 4.0 cm^–1. All data were recorded in the spectral range of 4000–400 cm^–1.

The X-ray diffraction (XRD) pattern of the CeO₂-NPs/GO/PAM hydrogel was determined using a Rigaku Ultima IV X-ray diffractometer (Tokyo, Japan) using Cu Kα radiation (λ = 1.5418Å, 40 kV, 40 mA).

The particle morphology of the CeO₂-NPs/GO/PAM hydrogel was investigated using a LEO Supra VP 35 field emission scanning electron microscope (FE-SEM) system, and the elemental composition was estimated by energy-dispersive X-ray (EDX) spectroscopy.

The optical absorbance of PAM, GO-PAM, CeO₂-NPs/GO/PAM hydrogel solutions, CeO₂-NPs, and GO was recorded on a Shimadzu 1800 UV–vis spectrophotometer (Tokyo, Japan) in the range of 200–800 nm. In order to obtain the UV–vis spectrum of CeO₂-NPs, 2.5 mg of the nanoparticles was weighed and dispersed in 5 mL of deionized water using an ultrasonicator for 10 min and magnetic stirrer for 1 h. For the UV–vis spectrum of GO, 300 μL of GO solution was added into the 5 mL of deionized water and dispersed by a magnetic stirrer for 1 h. The band gap energies of synthesized PAM, GO-PAM, and CeO₂-NPs/GO/PAM samples were determined by the Tauc plots obtained from the absorption spectra according to the following equation

(α h ν) = B {(h ν - E_{g})}^{r}

(1)

where α is the absorption coefficient, h is the Planck constant, ν is the frequency of the photon, B is the band-tail parameter, and E_g is the band gap energy.

2.4. Photocatalytic Degradation Experiments and Mineralization Studies

For the photocatalytic degradation of MB, 100 mg L^–1 stock solution of MB dye was prepared in distilled water and mixed until complete dissolution. The solution was stored in a dark place at room temperature. Standard solutions of the dye were diluted from the stock solution. The absorbance measurements were performed with a Shimadzu 1800 UV–vis spectrophotometer (Kyoto, Japan). A calibration curve was constructed by plotting the concentration of standard MB dye versus their absorbance values at 665 nm. The calibration equation obtained from the curve was used to determine the unknown concentration of MB during photocatalytic experiments.

A UV-light cabinet (Kerman Lab, Istanbul, Turkey) with 8 W (UV-A, UV-B, and UV-C) UV lamps was used for photodegradation studies. The lamps were high above 10 cm from the treated MB solution. At regular intervals, the absorbance of a certain amount of MB solution was measured and the taken amount was re-added into the degradation medium. Degradation studies were also performed in sunlight with the same experimental conditions. Furthermore, an experiment was conducted in a dark place in order to understand the adsorption uptake of the hydrogel.

The photocatalytic degradation of MB dye by CeO₂-NPs and GO was also studied. In order to test the CeO₂-NPs on MB degradation, 2.5 mg of CeO₂-NPs was added into 10 mL of 5 mg L^–1 MB solution. The mixture was ultrasonicated for 10 min and then stirred using a magnetic stirrer for one hour. The photocatalytic experiment was performed by irradiating UV-A light source under vigorous stirring. After that, nanoparticles were separated from the solution by centrifugation at 7000 rpm for five minutes in a Sigma 2–16P centrifuge (Sigma Laborzentrifugen, Germany). For the degradation of MB solution by GO, 300 μL of GO solution was added into 10 mL of 5 mg L^–1 MB solution, stirred using a magnetic stirrer for one hour, and placed into the UV-light cabinet.

Degradation experiments were done three times. The percentage of MB dye degradation was calculated using the formula below

degradation % = \frac{C_{i} - C_{t}}{C_{i}} \times 100

(2)

where C_i and C_t are initial and instantaneous concentrations of MB at a certain time, respectively.

In order to obtain the most effective degradation conditions, parameters such as the effect of the pH of MB solution, initial concentration of MB solution, photocatalyst amount, CeO₂-NP amount, GO amount, and type of light irradiation were investigated. Moreover, the reusability of the CeO₂-NPs/GO/PAM composite hydrogel was investigated at optimum conditions.

A kinetic experiment for MB dye degradation was carried out under optimized conditions using the absorbance of dye solution measured at 0, 15, 30, 45, 60, 75, and 90 min.

The methylene blue dye was also analyzed for mineralization based on the total organic carbon (TOC) and chemical oxygen demand (COD) removal (%). The TOC analysis was done using a TOC analyzer (TOC-VCPN, Shimadzu, Japan) before and after the photocatalysis of the MB dye using the standard SM 5310B method. The TOC removal efficiency was calculated as

TOC removal (%) = \frac{TO C_{i} - TO C_{t}}{TO C_{i}} \times 100

(3)

where TOC_i and TOC_t are the total organic carbon concentrations (mg L^–1) of the MB dye before and after photocatalysis, respectively.

The COD of the MB dye before and after photocatalysis was analyzed with an MAC COD digester (model: COD-439, Karnal, India) using the ISO 6060 method. The COD removal efficiency was calculated as

COD removal (%) = \frac{CO D_{i} - CO D_{t}}{CO D_{i}} \times 100

(4)

where COD_i and COD_t are the chemical oxygen demand concentrations (mg L^–1) of the MB dye before and after photocatalysis, respectively.

2.5. Quencher Experiments of the CeO₂-NPs/GO/PAM Hydrogel

The photocatalysis mechanism was validated by quencher experiments based on the free-radical capture of the CeO₂-NPs/GO/PAM hydrogel. Silver nitrate, ammonium oxalate, benzoquinone, and tert-butyl alcohol were used as e^–, h⁺, ^•O₂^–, and ^•OH scavengers, respectively. (37) The experiments were performed similar to the photocatalytic experiments. The only change in quench experiments was the addition of 1 mmol L^–1 scavengers to the MB solution.

2.6. Determination of the Point of Zero Charge (PZC)

The PZC value is the point at which all active sites become neutral, and so the material’s surface becomes zero. The PZC of the CeO₂-NPs/GO/PAM hydrogel was determined by the pH drift method. The pH of the 0.1 mol L^–1 NaNO₃ was adjusted to a value between 2 and 12 using 0.1 mol L^–1 HCl or 0.1 mol L^–1 NaOH.

The hydrogel (0.1 g) was added to 20 mL of the pH-adjusted solution in a capped vial. The vial was shaken up in a shaker and equilibrated for 24 h. The final pH was measured and plotted against the initial pH. The pH at which the curve crosses the pH_initial = pH_final line was taken as the PZC.

3. Results and Discussion

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3.1. Characterization of the CeO₂-NPs/GO/PAM Hydrogel

The FTIR spectrum of the CeO₂-NPs/GO/PAM hydrogel is given in Figure 2a. The main bands occurred at 3318 and 3174 cm^–1 are attributed to the asymmetric stretching band of NH₂ and primary amide NH₂ symmetric stretching band, respectively. (38) In this region, GO shows a strong and broad O–H stretching vibration band. Secondary amide II overtone was observed at 2919 cm^–1. The primary amide and secondary amide C═O stretching (CONH₂) bands occurred at 1642 and 1594 cm^–1, respectively. The O–H deformation vibration band occurred at 1439 cm^–1, and the C–O stretching vibration band at 1190 cm^–1 was observed for GO. (39) In the case of the spectrum obtained after the photocatalysis of MB (Figure 2b), there is no change of the both intensities and positions of infrared bands. This result confirmed the chemical stability of the hydrogel under photocatalysis.

Figure 2. FTIR spectra of the CeO₂-NPs/GO/PAM hydrogel **(a)** before and **(b)** after photocatalysis of MB dye.

The X-ray diffraction (XRD) patterns of CeO₂-NPs/GO/PAM hydrogels before and after photocatalysis are shown in Figure 3a,b, respectively. For the identification of cerium oxide nanoparticles, the peaks were indexed using ICDD No. 34–0394. The diffractograms of the hydrogels are consistent with that of the cerium oxide nanoparticle. All of the distinct peaks at 2 theta (2θ) values of about 28.6, 33.1, 47.5, and 56.3, representing the 111, 200, 220, and 311 Bragg reflections of the face-centered cubic structure of cerium oxide, confirm the presence of CeO₂ nanoparticles in the hydrogel. These major characteristic peaks confirmed the successful incorporation and uniform distribution of CeO₂-NPs into the GO/PAM matrix. In addition, no diffraction peaks related to GO were detected, which might be due to its high dispersion in the PAM hydrogel. The XRD profile of the powdered CeO₂-NPs/GO/PAM hydrogel retrieved after the photocatalytic degradation is similar to that of the powdered hydrogel before photocatalysis. The results of the XRD pattern comparison between before photocatalysis and after the MB photodegradation revealed that the patterns were remarkably similar. No changes in either XRD peak intensities or in the interplanar spacing were observed after the photocatalytic experimentation. This indicates that the CeO₂-NPs/GO/PAM hydrogel had chemical stability.

Figure 3. XRD patterns of the CeO₂-NPs/GO/PAM hydrogels (a) before and (b) after photocatalysis of MB dye.

The surface morphology of the CeO₂-NPs/GO/PAM hydrogel was analyzed in SEM. Figure 4a,b shows the SEM micrograph of the hydrogel before and after photocatalysis, respectively. There is no phase separation between polyacrylamide and CeO₂-NPs/GO, which means that the synthesized hydrogel has a good porous structure. After the photocatalytic process, there is no significant change in the morphological structure of the photocatalyst.

Figure 4. SEM micrographs of the CeO₂-NPs/GO/PAM hydrogel (a) before and (b) after photocatalysis of MB dye.

The energy-dispersive X-ray (EDX) spectrum of the CeO₂-NPs/GO/PAM hydrogel is shown in Figure 5. The percentages of the elements, i.e., C, O, and Ce are given on the graph.

Figure 5. EDX spectra of the CeO₂-NPs/GO/PAM hydrogel. The inset table shows the EDX quantification.

Figure 6 depicts UV–vis spectra of PAM, GO, GO/PAM, CeO₂-NPs, and CeO₂-NPs/GO/PAM hydrogel solutions recorded in the spectrum range of 200–800 nm. The maximum value of absorbance is observed in the UV region, and it decreases with increasing wavelengths for all solutions. In general, when examined in terms of conductivity, PAM is an insulating material. It was tried to obtain a semiconducting material for a photocatalytic activity by inserting CeO₂-NPs and GO into it.

Figure 6. UV–vis spectra of the **(a)**PAM, **(b)**GO, **(c)**GO/PAM, **(d)**CeO₂-NPs, and **(e)**CeO₂-NPs/GO/PAM hydrogel solutions.

Electronic transitions can occur in direct allowed (r = 1/2), direct forbidden (r = 3/2), indirect allowed (r = 2), and indirect forbidden (r = 3) states. Since CeO₂-NPs and GO doping inside PAM is considering to manifest a direct allowed transition, in Figure 7, Tauc plots of (αhν)² versus hν are given. In comparison to the absorbance response of PAM, GO addition to PAM presents a red shift in the spectrum due to the narrower band gap energy of GO around 2.2 eV. (40) For the GO/PAM composite gel, band gap energy is calculated as 3.46 eV from the Tauc plots. CeO₂-NP addition improves the photocatalytic performance decreasing the band gap energy of the hydrogel to 2.55 eV.

Figure 7. (a) Tauc plots of the hydrogel solutions. Extrapolations of the linear portions of the curves for (b) GO/PAM and (c) CeO₂-NPs/GO/PAM.

In addition to the Tauc method, the band gap energy can be calculated approximately from the absorbance–wavelength curve. The absorbance–wavelength curve usually gives a peak if the material contains quantum dots (or particles with about 10–20 nm). Band gap energy can be calculated according to the hc/λ formula of the wavelength equivalent of the peak (maximum of absorbance) corresponding value on the x-axis. (41) In composite materials containing nanoparticles, especially polymer composites, the absorbance curve sometimes does not have a peak. In this case, for the calculation of band gap energy, extrapolation is made from the region where the curve first flattens to the wavelength axis, and approximately the band gap energy value of the composite is calculated according to the hc/λ formula of the wavelength at which it intersects. In this case, as a result of the extrapolations done in Figure 8, the wavelength values for GO/PAM and CeO₂-NPs/GO/PAM were found to be 358.1044 and 487.2894 nm, respectively, and the corresponding band gap energy values were 3.46 and 2.44 eV. These values were found to be compatible with the band gap values calculated from the Tauc plots (Figure 7). Therefore, it can be verified that the electronic transition behavior is directly allowed transition.

Figure 8. Band gap energy estimation of PAM, GO/PAM, and CeO₂-NPs/GO/PAM hydrogels.

3.2. Effect of the Amounts of CeO₂-NPs and GO on Photocatalytic Degradation

The effect of the amounts of CeO₂-NPs and GO on the photocatalytic degradation of MB dye is given in Figure 9a,b, respectively. The dye removal in PAM-added solutions appears to be about 20% under UV light. When the experiment was repeated by exposing methylene blue solution to UV light without the addition of catalysis, degradation at this rate was also detected. Therefore, while PAM has no effect on degradation, CeO₂-NP addition to the PAM hydrogel from 1 to 2.5 mg, significantly increased the degradation percentage of MB. However, with 3 mg of CeO₂-NPs, a slight decrease was seen in the degradation percentage. Thus, the optimum CeO₂-NP amount was determined as 2.5 mg. The PAM hydrogel doped with 2.5 mg CeO₂-NPs degraded MB dye as 65%.

Figure 9. Effect of the amount of (a) CeO₂-NPs and (b) GO in the PAM hydrogel on the photocatalytic degradation of MB dye.

Subsequently, the effect of GO addition to the hydrogel system on the degradation rate was studied with 100–400 μL of GO solution. The MB degradation increased when the GO amount increased from 100 to 300 μL. However, a slight decrease was observed with the addition of 400 μL of GO. The GO amount was adjusted to 300 μL. Therefore, the photocatalyst was prepared using the following: 500 mg of AA, 10 mg of MBA, 8 mg of APS, 2 μL of TEMED (0.775 g mL^–1), 2.5 mg of CeO₂-NPs, and 300 μL of GO. All photocatalysis studies were carried out with this composition.

To find the optimum CeO₂-NPs-to-GO ratio on photocatalytic activity, the ratios ranging from 1:30 to 1:400 (CeO₂-NPs-to-GO and weight-to-volume ratios, mg μL^–1) were studied. The optimum CeO₂-NPs-to-GO ratio was found to be as 1:120 (w/v). Thus, 2.5 mg of CeO₂-NPs were mixed with 300 μL of GO, and after that, the hydrogel synthesis was performed.

3.3. Effect of pH and the Initial Concentration of MB Solution

The effect of pH on the photocatalytic activity of composite hydrogels was investigated between pH 2.0 and 12.0 using 5 mg L^–1 MB dye as the initial dye concentration and 0.3 g of the dried hydrogel as the photocatalyst amount. The pH of 5 mg L^–1 MB dye was measured as 6.0, and this solution was adjusted to the mentioned pH values using 1 mol L^–1 NaOH or 1 mol L^–1 HCl. For the experiment performed at pH 6.0, pH adjustment was not performed.

Figure 10a shows % degradation vs. time for varying pH values of 5 mg L^–1 MB solutions under UV-A light. The highest degradation percent was obtained at pH 12 in 90 min. It is known that the surface charge of CeO₂-NPs is sensitive to pH, and at pH 12, the surface charge of particles is negative. (22) Since the point of zero charge determined by the pH drift method of the CeO₂-NPs/GO/PAM composite was pH 3.0, the surface charge in the composite is negative. MB is a cationic dye, so a strong electrostatic interaction between the dye and the nanoparticles occurs. This interaction further initiates the photocatalysis effect of CeO₂-NPs.

Figure 10. Effect of (a) pH and (b) initial concentration of MB solution.

The effect of the initial dye concentration on the photocatalysis of MB was tested in the concentration range of 2.5–10 mg L^–1, keeping the photocatalyst amount at 0.3 g and MB solution pH at 12. When the initial concentration of MB solution increased from 2.5 to 5 mg L^–1, the percentage of dye removal increased as shown in Figure 10b. However, when the methylene blue concentration increased to 10 mg L^–1, a decrease in photocatalytic activity was observed. This could be due to methylene blue molecules obstructing the portions of the cerium oxide surface that are triggered by light. Therefore, the formation of ^•OH radicals, which cause the dye to be oxidized and thus degraded, may be prevented. Thus, the optimum MB concentration was selected as 5 mg L^–1.

3.4. Effect of the Type of Light Irradiation

The effect of the type of light irradiation on MB dye degradation is shown in Figure 11. Under UV-A light, 90% of dye degradation occurred in 90 min, while 50% of the dye degraded in 90 min under sunlight. This result shows that sunlight had no significant effect on MB dye degradation.

Figure 11. Effect of the type of light irradiation on MB dye degradation.

For further experiments, the effect of different UV-light sources was investigated. Photocatalysts containing MB dye solutions were irradiated by UV-A (315–400 nm), UV-B (280–315 nm), and UV-C (100–280 nm) light sources. As shown in Figure 11, the maximum dye degradation (90%) was obtained under UV-A light irradiation with the shortest equilibrium time (90 min).

The experiment was also conducted under dark conditions in order to understand the adsorption process between the positively charged MB dye and neutral CeO₂-NPs/GO/PAM hydrogels. Only ∼30% of dye was degraded with adsorption in 90 min.

3.5. Photocatalytic Degradation Mechanism of MB Dye by CeO₂-NPs/GO/PAM

According to the common pathway, the photoexcitation of CeO₂ in an aqueous solution during the photocatalytic degradation of contaminants leads to the formation of different radicals and charged species. (30) The proposed mechanism of dye degradation involves a series of reactions as given in eqs 5–8.

When photons are absorbed by CeO₂ electrons, hole pairs can be generated inside CeO₂.

{CeO}_{2} + h ν (UV) \to {CeO}_{2}^{*} ({e_{CB}}^{-} + {h_{ν B}}^{+})

(5)

Here, CeO₂* is the excited state of CeO₂, e_CB^– is a photoexcited electron in the conduction band, and h_VB⁺ is a photogenerated hole in the valence band. (30)

Photogenerated holes directly oxidize the dye to reactive intermediates as shown in eq 6. In the indirect process, the oxygen and water molecules are adsorbed on the photocatalyst’s surface. These molecules react with the electron–hole pairs (eqs 7 and 8) to produce the unstable hydroxyl radicals (^•OH) and superoxide ions (^•O₂^–), which oxidize the organic pollutants into the inorganic compounds (eqs 9 and 10).

{h_{ν B}}^{+} + MB \to {MB}^{\cdot +} \to oxidation of MB

(6)

O_{2} + {e_{CB}}^{-} \to {}^{•}{O_{2}}^{-}

(7)

H_{2} O + {h_{VB}}^{+} \to {OH}^{•} + H^{+}

(8)

and

{}^{•}{O_{2}}^{-} + MB dye \to {CO}_{2} + H_{2} O

(9)

{OH}^{•} + MB dye \to {CO}_{2} + H_{2} O

(10)

Moreover, GO works as an electron acceptor, which helps in the transfer of photoexcited electrons from the CeO₂ conduction band to GO. (32) This could lead a synergetic effect on the photocatalytic degradation of MB.

In order to further verify the methylene blue degradation and identify the photocatalytic degradation pathways, free-radical capture studies were performed by using silver nitrate (AgNO₃), ammonium oxalate (AO), benzoquinone (BZQ), and tert-butyl alcohol (t-ButOH) as e^–, h⁺, ^•O₂^–, and ^•OH scavengers, respectively. The results are given in Figure 12. As shown in Figure 12, when 1 mmol L^–1 BZQ was added into the 5 mg L^–1 MB dye, the hydrogel degraded the dye as 79%. This value is close to the obtained result from the media without any scavenger (90%). It means that ^•O₂^– is the main reactive species in the photocatalytic degradation of MB dye by the CeO₂-NPs/GO/PAM hydrogel. Moreover, a significant inhibition of MB photocatalytic degradation was also observed in the presence of t-ButOH, which shows the role of ^•OH in the photocatalytic process. The MB was degraded as 53% by the introduction of 1 mmol L^–1t-ButOH to the photocatalysis media. The effects of the pathway with the participation of e^– and h⁺ were more or less the same. The results indicated that the degradation efficiency decreased to 49 and 46%, with the addition of AgNO₃ and AO, respectively.

Figure 12. Photocatalytic degradation of MB dye under different scavengers.

Since CeO₂ is characterized by a relatively high band gap energy and high rate of e^–/h⁺ pair recombination, it has been widely applied in the photocatalytic degradation of MB dye. Examples of CeO₂-NP literature application as single photocatalysis in MB degradation are presented in Table 1. Only one study showed a degradation efficiency of 95% using a CeO₂-NPs/GO composite as the photocatalyst but longer time compared to our result. (27)

Table 1. Degradation of MB by CeO₂-NPs Obtained from Previous Studies

photocatalyst	degradation efficiency (%)	reaction time (min)	initial MB concentration (mg L^–1)	ref
CeO₂-NPs	83.9–93.4	105	5	(23)
CeO₂-NPs	95	125	5	(42)
CeO₂-NPs	90.4	90	20	(43)
CeO₂-NPs	77	210	12.5	(44)
CeO₂-NPs	80	120	10	(45)
CeO₂-NPs/GO	95	120	20	(27)
CeO₂-NPs/GO	90	90	5	this study

Expressing the band gap shift as a function of photocatalytic degradation ability is also insightful. Thus, Figure 13 gives the band diagrams of the hydrogels with band energies obtained from Tauc plots.

Figure 13. Band gap diagram of GO/PAM and CeO₂-NPs/GO/PAM constructed from UV–vis spectroscopy and Tauc plots.

3.6. Methylene Blue (MB) Mineralization

The amount of MB mineralization is measured by the reduction in total organic carbon (TOC) and chemical oxygen demand (COD). For this purpose, TOC and COD tests were performed to determine the mineralization of the MB dye using the CeO₂-NPs/GO/PAM hydrogel.

A remarkable decrease in TOC was obtained that implies efficient mineralization of MB with CeO₂-NPs/GO/PAM. The TOC decreased from 70 to 6 mg L^–1, which corresponded to 91% removal of the MB dye. This result was supported by experimental photocatalytic degradation of the MB (90%). Similarly, the decrease in COD reveals the degree of associated organic species’ mineralization. The degradation of the MB dye was 78% when the COD decreased from 220 to 47 mg L^–1.

3.7. Kinetic Modeling of Dye Degradation

The Langmuir–Hinshelwood kinetic model was applied to experimental data. (5,46) This model covers the kinetics of heterogeneous catalytic processes. The degradation experiments by UV-A irradiation of MB solutions containing CeO₂-NPs/GO/PAM composite hydrogels follow the pseudo-first-order kinetics

r = - \frac{d c}{d t} = K_{app} \cdot C

where r is the photocatalytic degradation rate (mg L^–1 min^–1), C is the concentration of the dye in the bulk solution (mg L^–1), t is the irradiation time, and K_app is the apparent degradation rate constant (min^–1). Integration of this equation gives the following relation

\ln (\frac{C_{0}}{C}) = K_{app} \cdot C

in which C₀ is the initial concentration in the bulk solution.

It is found that the ln(C_t/C₀) vs irradiation time plot follows a linear kinetic relationship as shown in Figure 14. The reaction rate constant of degradation as the slope of the line was 0.0259 min^–1. The regression coefficient (R²) was found to be 0.9504.

Figure 14. Langmuir–Hinshelwood plot for photodegradation of MB with CeO₂-NPs/GO/PAM.

3.8. Reusability of CeO₂-NPs/GO/PAM Hydrogels

The capability to reuse a photocatalyst is critical for cost-effective industrial use. The reusability of the CeO₂-NPs/GO/PAM hydrogel was examined over nine repeat (10 in total) cycles as shown in Figure 15. The hydrogel was dried after the first degradation. The hydrogel was recontacted with the MB solution under the determined optimized conditions. In the second use of the catalyst, the dye removal decreased to 85%. In the fifth repeat cycle, the photocatalyst was active with a >80% removal efficiency, which supports the reusability of hydrogels. In the ninth repeat cycle, 75% of the dye was decreased. Since the degradation efficiency was decreased to 70% in the 10th use of the hydrogels, the results of nine repetitions were given.

Figure 15. Reusability of the CeO₂-NPs/GO/PAM hydrogel.

4. Conclusions

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In this study, CeO₂ nanoparticles and GO-doped PAM hydrogels were synthesized. XRD analysis clearly indicates that the addition of CeO₂ nanoparticles was successfully incorporated into the PAM hydrogel, which is further supported by the FTIR analysis. The produced hydrogel was employed for the photodegradation of methylene blue dye from an aqueous solution. In the optimized conditions, 90% dye degradation efficiency was observed. Considering its high dye removal efficiency and favorable reusability, it is anticipated that this hydrogel may be used in practical wastewater treatment.

Author Information

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Corresponding Author
- F. Bedia Erim - Department of Chemistry, Faculty of Science and Letters, Istanbul Technical University, Maslak, Istanbul 34469, Turkey; https://orcid.org/0000-0001-9406-6681; Email: [email protected]
Authors
- Zeynep Kalaycıoğlu - Department of Chemistry, Faculty of Science and Letters, Istanbul Technical University, Maslak, Istanbul 34469, Turkey; https://orcid.org/0000-0002-0967-0997
- Bengü Özuğur Uysal - Faculty of Engineering and Natural Sciences, Kadir Has University, Cibali, Fatih, Istanbul 34083, Turkey
- Önder Pekcan - Faculty of Engineering and Natural Sciences, Kadir Has University, Cibali, Fatih, Istanbul 34083, Turkey
Notes
The authors declare no competing financial interest.

Acknowledgments

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This research was performed at Istanbul Technical University, Capillary Electrophoresis, and Biopolymer Applications Research Laboratory. The research facilities of the laboratory are covered by the Research Foundation of Istanbul Technical University.

References

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This article references 46 other publications.

1
Owa, F. W. Water pollution: sources, effects, control and management. Int. Lett. Nat. Sci. 2014, 8, 1– 6, DOI: 10.56431/p-gk4d9j
Google Scholar
There is no corresponding record for this reference.
2
Liu, Q. Pollution and treatment of dye waste-water. IOP Conf. Ser.: Earth Environ. Sci. 2020, 514, 514, DOI: 10.1088/1755-1315/514/5/052001
Google Scholar
There is no corresponding record for this reference.
3
Wani, K. A.; Jangid, N. K.; Bhat, A. R. Impact of Textile Dyes on Public Health and the Environment in Advances in Human Services and Public Health, IGI Global, 2019.
Google Scholar
There is no corresponding record for this reference.
4
Azimi, S. C.; Shirini, F.; Pendashteh, A. R. Advanced oxidation process as a green technology for dyes removal from wastewater: A review. Iran. J. Chem. Chem. Eng. 2021, 40, 1467– 1489, DOI: 10.30492/IJCCE.2020.43234
Google Scholar
4
Advanced oxidation process as a green technology for dyes removal from wastewater: a review
Azimi, Seyyedeh Cobra; Shirini, Farhad; Pendashteh, Ali Reza
Iranian Journal of Chemistry & Chemical Engineering (2021), 40 (5), 1467-1489CODEN: IJCEE9; ISSN:1021-9986. (Iranian Research and Development Center for Chemical Industries)
A review. The combination of green chem. and green engineering is needed for the prodn. of min. waste, renewable sources, increasing utilization of raw materials, the use of simpler and safer products, and novel technologies. The use of novel cleaner technologies leads to effective prodn. in chem. industries. The dyes involve a complex structure, recalcitrant nature, and more intermediates. The generation of oxidative species with higher yields is obtained by advanced oxidn. processes as a green and powerful treatment technol. These processes are effective, inexpensive, and eco-friendly methods for decaying toxic pollutants. The AOPs are classified as non-photochem. and photochem. processes. There are included various technologies such as ozonation, Fenton oxidn., wet air oxidn., electrochem. oxidn., and photocatalytic oxidn. The prodn. of highly reactive free radicals is the main purpose of the AOPs process. The generation of free radical increases by the combination of two or more AOPs processes that leads to higher oxidn. rates. This study was aimed to present the various attempts for degrdn. dyes in textile wastewater using the diverse advanced oxidn. processes.
5
Karadeniz, D.; Kahya, N.; Erim, F. B. Effective photocatalytic degradation of malachite green dye by Fe (III)-Cross-linked Alginate-Carboxymethyl cellulose composites. J. Photochem. Photobiol. 2022, 428, 113867 DOI: 10.1016/j.jphotochem.2022.113867
Google Scholar
5
Effective photocatalytic degradation of malachite green dye by Fe(III)-cross-linked alginate-carboxymethyl cellulose composites
Karadeniz, Duygu; Kahya, Nilay; Erim, F. Bedia
Journal of Photochemistry and Photobiology, A: Chemistry (2022), 428 (), 113867CODEN: JPPCEJ; ISSN:1010-6030. (Elsevier B.V.)
Fe(III) ion cross-linked alginate-CM-cellulose composite beads (Fe@(Alg-CMC)) were prepd. and used as a novel photocatalyst for the degrdn. of malachite green (MG) dye. Fe (III) ions bound to the carboxyl groups of the biopolymer composite provided reactive radicals under UV light, and degrdn. of the dye in an aq. soln. occurred at a high percentage and in a short time. Unlike Fenton's reaction, effective degrdn. of the dye was carried out without adding H2O2 to the medium. Optimum conditions of dye degrdn. were investigated. Under UV-A light, 98.8%±0.7% dye degrdn. was achieved at pH 4 of 10 ppm MG soln. with 0.1 g of Fe@(Alg-CMC) beads in 30 min. Exptl. results fitted Langmuir-Hinshelwood kinetic modeling, which explains the kinetics of the heterogeneous catalytic processes. A rate const. (k) of 0.115 ± 0.001 min-1 and correlation coeff. (R2) of 0.9628 was obtained. Hereby, we offer Fe@(Alg-CMC) beads as a promising, environmentally friendly, easy to prep., and low-cost catalyst for the degrdn. of dyes and org. substances under UV light.
6
Ameta, R.; Benjamin, S.; Ameta, A.; Ameta, S. C. Photocatalytic degradation of organic pollutants: A review. Mater. Sci. Forum. 2013, 734, 247– 272, DOI: 10.4028/www.scientific.net/MSF.734.247
Google Scholar
6
Photocatalytic degradation of organic pollutants: a review
Ameta, Rakshit; Benjamin, Surbhi; Ameta, Aarti; Ameta, Suresh C.
Materials Science Forum (2013), 734 (Photocatalytic Materials & Surfaces for Environmental Cleanup II), 247-272, 27 pp.CODEN: MSFOEP; ISSN:1662-9752. (Trans Tech Publications Ltd.)
A review. Water pollution is increasing at an ever increasing pace and the whole world is in the cancerous grip of this pollution. Various industries are discharging their untreated effluents into the nearby water resources; thus, adding to the existing water pollution to a great extent. Hence, there is a pressing demand to develop an alternate technol. for wastewater treatment and in this context; photocatalysis has emerged as an Advanced Oxidn. Process with green chem. approach for such a treatment. This chapter deals with photocatalytic degrdn. of different kinds of org. pollutants; mainly surfactants, pesticides, dyes, phenols, chloro compds., nitrogen contg. compds. etc. Mechanisms of their degrdn. have also been discussed with hydroxyl and allied radicals as the main active oxidizing species.
7
Godiya, C. B.; Xiao, Y.; Lu, X. Amine functionalized sodium alginate hydrogel for efficient and rapid removal of methyl blue in water. Int. J. Biol. Macromol. 2020, 144, 671– 681, DOI: 10.1016/j.ijbiomac.2019.12.139
Google Scholar
7
Amine functionalized sodium alginate hydrogel for efficient and rapid removal of methyl blue in water
Godiya, Chirag B.; Xiao, Yonghou; Lu, Xiaolin
International Journal of Biological Macromolecules (2020), 144 (), 671-681CODEN: IJBMDR; ISSN:0141-8130. (Elsevier B.V.)
Herein, a potential hydrogel based on sodium alginate (SA) integrated with polyethyleneimine (PEI) was fabricated and employed for the elimination of methyl blue (MB) in aq. media. The SA/PEI hydrogel demonstrated excellent removal performance for MB, i.e. ~ 99% of MB could be removed from water within ~ 30 min using 0.5 g/L SA/PEI hydrogel at 100 mg/L initial concn. The SA/PEI hydrogel presented max. adsorption capacity for MB as-high as 400.0 mg/g with the adsorption isotherm and kinetics abide with the Langmuir isotherm model and pseudo second-order kinetics, resp. The adsorption process followed through chelation between the functionality of the hydrogel and MB as-confirmed by the XPS anal. After four consecutive adsorption/desorption cycles, the adsorption capacity of the SA/PEI hydrogel remained up to ~ 60% of its adsorption capacity in first cycle. Thus, being a cost-effective and eco-friendly material, the SA/PEI hydrogel can be a potential adsorbent in the decontamination of MB in wastewater.
8
Lapwanit, S.; Sooksimuang, T.; Trakulsujaritchok, T. Adsorptive removal of cationic methylene blue dye by kappacarrageenan/poly(glycidyl methacrylate) hydrogel beads: Preparation and characterization. J. Environ. Chem. Eng. 2018, 6, 6221– 6230, DOI: 10.1016/j.jece.2018.09.050
Google Scholar
8
Adsorptive removal of cationic methylene blue dye by kappa-carrageenan/poly(glycidyl methacrylate) hydrogel beads: Preparation and characterization
Lapwanit, Songwut; Sooksimuang, Thanasat; Trakulsujaritchok, Thanida
Journal of Environmental Chemical Engineering (2018), 6 (5), 6221-6230CODEN: JECEBG; ISSN:2213-3437. (Elsevier Ltd.)
Kappa-carrageenan hydrogel contg. numerous functional groups used as an environmental-friendly adsorbent shows limitations due to its high water soly., low gel strength and low regeneration ability. In this work, a new biopolymeric-based hydrogel of κ-carrageenan/poly(glycidyl methacrylate) (CG/PG) was prepd. for adsorptive removal of cationic methylene blue (MB) as a toxic dye model. The physicochem. properties and morphol. of the hydrogel beads were characterized by swelling test, FT-IR, TGA and SEM. Parameters affecting the adsorption of MB from aq. soln. such as CG/PG ratios, initial dye concn., soln. pH, time, adsorbent dosage and soln. temp. were investigated in a batch system. Incorporation of PG with reactive function groups into the CG matrix was proven to enhance the adsorption capacity and stability of the hydrogel required for the application of adsorbent as compared to the pristine CG biopolymer. The exptl. adsorption followed pseudo-second order model and well fitted with Langmuir isotherm, with max. MB adsorption of 166.62 mg g-1. Thermodn. parameters indicated that the process was spontaneous and exothermic. The beads could be easily regenerated after washing with ethanol and reused for at least five adsorption-desorption cycles with high efficiency. The fabrication of CG/PG hydrogel beads provided a feasible strategy for the design and modification of bio-based polymers in the field of wastewater treatment.
9
Hu, T.; Liu, Q.; Gao, T.; Dong, K.; Wei, G.; Yao, J. Facile preparation of tannic acid–poly(vinyl alcohol)/sodium alginate hydrogel beads for methylene blue removal from simulated solution. ACS Omega 2018, 3, 7523– 7531, DOI: 10.1021/acsomega.8b00577
Google Scholar
9
Facile Preparation of Tannic Acid-Poly(vinyl alcohol)/Sodium Alginate Hydrogel Beads for Methylene Blue Removal from Simulated Solution
Hu, Tao; Liu, Qinze; Gao, Tingting; Dong, Kaijie; Wei, Gang; Yao, Jinshui
ACS Omega (2018), 3 (7), 7523-7531CODEN: ACSODF; ISSN:2470-1343. (American Chemical Society)
A novel hydrogel bead [tannic acid (TA)-poly(vinyl alc.) (PVA)/sodium alginate (SA)] with high strength prepd. by biocompatible PVA, TA, and biocompatible SA via an instantaneous gelation method was applied to remove methylene blue (MB) from aq. soln. The obtained TA-PVA/SA hydrogel beads were fully characterized by thermogravimetric anal., Fourier-transform IR spectroscopy, XPS, SEM, and so on. The adsorption performances of TA-PVA/SA hydrogel beads for MB were investigated by changing the factors of TA content, initial concn., pH, adsorbent dosage, contact time, and temp. systematically. The max. capacity of TA-PVA/SA hydrogel beads for MB removal was obtained to be 147.06 mg/g at 30 °C, whose capability was better than that without TA. After fitting the adsorbed data, it was basically consistent with the Langmuir isotherm and pseudo-second-order kinetic model. Thermodn. studies indicated that MB removal was spontaneous and exothermic in nature. It is concluded that the low-cost TA-PVA/SA hydrogel beads as an easily recoverable adsorbent have a great potential on the removal of hazardous dyes from wastewater.
10
Malatji, N.; Makhado, E.; Modibane, K. D.; Ramohlola, K. E.; Maponya, T. C.; Monama, G. R.; Hato, M. J. Removal of methylene blue from wastewater using hydrogel nanocomposites: A review. Nanomater. Nanotechnol. 2021, 11, 1– 27, DOI: 10.1177/18479804211039425
Google Scholar
There is no corresponding record for this reference.
11
Pereira, A. G. B.; Rodrigues, F. H. A.; Paulino, A. T.; Martins, A. F.; Fajardo, A. R. Recent advances on composite hydrogels designed for the remediation of dye-contaminated water and wastewater: A review. J. Cleaner Prod. 2021, 284, 124703 DOI: 10.1016/j.jclepro.2020.124703
Google Scholar
11
Recent advances on composite hydrogels designed for the remediation of dye-contaminated water and wastewater: A review
Pereira, Antonio G. B.; Rodrigues, Francisco H. A.; Paulino, Alexandre T.; Martins, Alessandro F.; Fajardo, Andre R.
Journal of Cleaner Production (2021), 284 (), 124703CODEN: JCROE8; ISSN:0959-6526. (Elsevier Ltd.)
A review. Dye-contamination in water supplies, industrial effluents, and rivers is one of the major water pollution issues. It has put at risk the drinking-water supplies around the globe. Various remediation approaches have been extensively developed and tested to minimize this worrying scenery. In particular, adsorption techniques are often ranked as one of the most prominent strategies to treat dye-contaminated water likely due to their attractive practical and economic advantages. Overall, the efficiency of adsorptive removal of dyes from water is closely related to the adsorbent material features, which has a crit. role in this process. Currently, thousands of materials (raw or processed) have been tested as adsorbents. Otherwise, none of them have achieved the prominent status assigned to the hydrogels. Frequently labeled as an ideal adsorbent, the leading role of these soft materials towards the adsorptive removal of dyes from the water was consolidated almost two decades ago, when the introduction of different materials into the hydrogel matrixes resulted in composite materials with unique properties. In this paper, an entirely conceptual and crit. review of literature is presented, focusing on the tremendous potential of composite hydrogels to remediate dye-contaminated water. Specifically, the main advances related to the use of composite hydrogels contg. clay minerals, carbonaceous materials, org. fibrils and whiskers, magnetic and metallic particles, and other inorg. fillers are reviewed in this paper. Addnl., general methods to prep. composite hydrogels, the main effects ascribed to the composite formation are addressed in this paper. Finally, the main drawbacks and challenges assocd. with the application of these types of hydrogels are reviewed to understand the research gap and limitations regarding their practical use. We believe that the information provided in this review paper may contribute to enhance the scientific basis for the practical and efficient use of these fascinating adsorbent materials.
12
Kahya, N.; Erim, F. B. Graphene oxide/chitosan-based composite materials as adsorbents in dye removal. Chem Eng Commun. 2022, 209, 1711– 1726, DOI: 10.1080/00986445.2021.1986700
Google Scholar
12
Graphene oxide/chitosan-based composite materials as adsorbents in dye removal
Kahya, Nilay; Erim, F. Bedia
Chemical Engineering Communications (2022), 209 (12), 1711-1726CODEN: CEGCAK; ISSN:0098-6445. (Taylor & Francis, Inc.)
A review. Chitosan (Chit) is among the most widely used polysaccharides. Another material that draws attention with its unique phys. and chem. properties is graphene oxide (GO). Reactive groups in the structure of both chitosan and graphene oxide make both materials ideal adsorbents. GO is an excellent adsorbent candidate with its large surface area and mech. strength. However, the difficulty in recovering GO particles as an adsorbent creates a secondary environmental problem. Chitosan shows a weak interest in pos. charged pollutants. The incorporation of GO into chitosan increases both the mech. strength and adsorption capacity of the chitosan. The GO/Chitosan composite also offers the advantage of attracting both pos. and neg. charged pollutants. Over the past five years, an increasing no. of articles have been published reporting the use of GO/Chitosan-based composite materials as adsorbents in dye removal. The adsorption properties of GO/Chitosan-based composites appear to change with the inclusion of materials like magnetite, nano-metal, and other polysaccharides. It is seen that the differences in the prepn. steps of composites of the same structure also affect their adsorption capacities. This paper aims to compile the works between Jan. 2016 and Dec. 2020 on GO/Chitosan-based composites, which were reported to remove dyes from wastewater.
13
Wang, W.; Wang, Y.; Zhao, Y.; Bai, H.; Huang, M.; Zhang, T.; Song, S. High-performance two-dimensional montmorillonite supported poly(acrylamide-co-acrylic acid) hydrogel for dye removal. Environ. Pollut. 2020, 257, 113574 DOI: 10.1016/j.envpol.2019.113574
Google Scholar
13
High-performance two-dimensional montmorillonite supported-poly(acrylamide-co-acrylic acid) hydrogel for dye removal
Wang, Wei; Wang, Jinggang; Zhao, Yunliang; Bai, Haoyu; Huang, Muyang; Zhang, Tingting; Song, Shaoxian
Environmental Pollution (Oxford, United Kingdom) (2020), 257 (), 113574CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
High-performance two-dimensional montmorillonite supported-poly (acrylamide-co-acrylic acid) hydrogel for dye removal was investigated. Montmorillonite cooperated with acrylamide and acrylic acid via polymn., hydrogen-bond, amidation and electrostatic interactions to form the three-dimensional reticular-structured hydrogel with the free entrance for macromols. Adsorption tests revealed that the efficient removal (97%) for methylene blue at high concn. (200 mg/L) could be achieved via a small dose of hydrogel (0.5 g/L) within a short time (20 min). The excellent adsorption performance was profited from the electroneg. surface and fully exposed reaction sites of two-dimensional montmorillonite, which could save the treatment cost and promote the removal effect compared with the conventional adsorbents. The adsorption process of methylene blue onto hydrogel could be fitted by both the pseudo-first-order and pseudo-second-order kinetics models, and the adsorption isotherm corresponded to the Sips model. The mechanism anal. based on Fourier transform IR spectroscopy and XPS measurements illustrated that the reaction between carboxyl groups and methylene blue mols. as well as the cation-exchange enabled the hydrogel performing extraordinary adsorption efficiency.
14
Balkız, G.; Pingo, E.; Kahya, N.; Kaygusuz, H.; Erim, F. B. Graphene oxide/alginate quasi-cryogels for removal of methylene blue. Water Air Soil Pollut. 2018, 229, 131, DOI: 10.1007/s11270-018-3790-5
Google Scholar
There is no corresponding record for this reference.
15
Dai, H.; Huang, Y.; Huang, H. Eco-friendly polyvinyl alcohol/carboxymethyl cellulose hydrogels reinforced with graphene oxide and bentonite for enhanced adsorption of methylene blue. Carbohydr. Polym. 2018, 185, 1– 11, DOI: 10.1016/j.carbpol.2017.12.073
Google Scholar
15
Eco-friendly polyvinyl alcohol/carboxymethyl cellulose hydrogels reinforced with graphene oxide and bentonite for enhanced adsorption of methylene blue
Dai, Hongjie; Huang, Yue; Huang, Huihua
Carbohydrate Polymers (2018), 185 (), 1-11CODEN: CAPOD8; ISSN:0144-8617. (Elsevier Ltd.)
Eco-friendly polyvinyl alc./CM-cellulose (isolated from pineapple peel) hydrogels reinforced with graphene oxide and bentonite were prepd. as efficient adsorbents for methylene blue (MB). The structure and morphol. of the prepd. hydrogels were characterized by Fourier transform IR spectroscopy (FTIR), scanning electron microscope (SEM), X-ray diffraction (XRD), thermogravimetry (TG) and differential scanning calorimetry (DSC). Introducing graphene oxide and bentonite into the hydrogels evidently enhanced the thermal stability, swelling ability and MB adsorption capacity. The effects of initial concn. of MB, pH, contact time and temp. on MB adsorption capacity of the prepd. hydrogels were investigated. Adsorption kinetics and equil. adsorption isotherm fitted pseudo-second-order kinetic model and Langmuir isotherm model well, resp. After introducing graphene oxide and bentonite into the hydrogels, the max. adsorption capacity calcd. from the Langmuir isotherm model reached 172.14 mg/g at 30 °C, obviously higher than the hydrogels prepd. without these addns. (83.33 mg/g). Furthermore, all the prepd. hydrogels also displayed good reusability for the efficient removal of MB. Consequently, the prepd. hydrogels could be served as eco-friendly, stable, efficient and reusable adsorbents for anionic dyes in wastewater treatment.
16
Uyar, G.; Kaygusuz, H.; Erim, F. B. Methylene blue removal by alginate-clay quasi-cryogel beads. React. Funct. Polym. 2016, 106, 1– 7, DOI: 10.1016/j.reactfunctpolym.2016.07.001
Google Scholar
16
Methylene blue removal by alginate-clay quasi-cryogel beads
Uyar, Guler; Kaygusuz, Hakan; Erim, F. Bedia
Reactive & Functional Polymers (2016), 106 (), 1-7CODEN: RFPOF6; ISSN:1381-5148. (Elsevier Ltd.)
Nowadays, dyes constitute a large part of pollutants and have long been used in dyeing, paper and pulp, textiles, plastics, leather, cosmetics, and food industries. Among the conventional dye removal techniques, adsorption is prominent. Research challenges are on developing low-cost, biodegradable and efficient adsorbents. This study investigates polysaccharide-clay composite beads for the removal of methylene blue dye. Alginate-montmorillonite composite beads were prepd. and then a novel cryogelation-like strategy was developed by deep-freezing the alginate beads at - 21°. This process changed the morphol. of beads and improved surface area and adsorption capacity. The results of the batch adsorption expts. were modeled using isothermal, kinetic, and thermodn. models. It is found that the adsorption is favorable and follows phys. mechanism, with an endothermic process up to 40°. The prepd. composite beads are candidates for effective adsorbents for the dye removal.
17
Heng, L.; Guo, X.; Guo, T.; Wang, B.; Jiang, L. Strengthening of polymer ordered porous materials based on a layered nanocomposite internal structure. Nanoscale 2016, 8, 13507– 13512, DOI: 10.1039/C6NR03011D
Google Scholar
17
Strengthening of polymer ordered porous materials based on a layered nanocomposite internal structure
Heng, Liping; Guo, Xieyou; Guo, Tianqi; Wang, Bin; Jiang, Lei
Nanoscale (2016), 8 (27), 13507-13512CODEN: NANOHL; ISSN:2040-3372. (Royal Society of Chemistry)
Ordered porous polymeric films attract more and more attention because they have many advantages and broad application prospects in many fields. Because of their large flexibility and poor mech. properties, some of the scope for application is greatly limited. Inspired by the ordered pore structure of the honeycomb and the layered structure of natural nacre, we prepd. an ordered porous polymer film with a layered structure in the pore wall by the solvent evapn.-restriction assisted hard template method. Compared with other samples, this kind of film with the layered structure showed both excellent mech. properties and good stability. This kind of film with high mech. strength, is considered to have wide applications in the areas of sepn., biomedicine, precision instruments, aerospace, environmental protection and so on.
18
Ikram, M.; Haider, A.; Bibi, S. T.; Ul-Hamid, A.; Haider, J.; Shahzadi, I. Synthesis of Al/starch co-doped in CaO nanoparticles for enhanced catalytic and antimicrobial activities: experimental and DFT approaches. RSC Adv. 2022, 12, 32142– 32155, DOI: 10.1039/D2RA06340A
Google Scholar
18
Synthesis of Al/starch co-doped in CaO nanoparticles for enhanced catalytic and antimicrobial activities: experimental and DFT approaches
Ikram, Muhammad; Haider, Ali; Bibi, Syeda Tayaba; Ul-Hamid, Anwar; Haider, Junaid; Shahzadi, Iram; Nabgan, Walid; Moeen, Sawaira; Ali, Salamat; Goumri-Said, Souraya; Kanoun, Mohammed Benali
RSC Advances (2022), 12 (50), 32142-32155CODEN: RSCACL; ISSN:2046-2069. (Royal Society of Chemistry)
In this work, aluminum/starch (St)-doped CaO nanoparticles (NPs) were synthesized by a co-pptn. method to degrade harmful dyes in various pH media. Systematic characterization was performed to investigate the influence of Al/St dopants on the compn., crystal structure, functional groups present, optical characteristics, and morphol. of CaO NPs. Further hybrid d. functional analyses corroborated that the band gap energy was reduced as the Al concn. in starch-doped CaO is increased. Optical absorption spectra of the synthesized materials revealed a red shift upon doping, which indicated depletion in the band gap energy of Al/St-doped CaO. PL spectroscopy showed that the intensity of CaO was reduced by the incorporation of Al and St assigned to min. electron-hole pair recombination. Interlayer spacing and morphol. features were detd. by HR-TEM. HRTEM revealed that the control sample has cubic NPs and the incorporation of St showed overlapping around agglomerated NPs. The d-spacing of CaO was little enhanced by the inclusion of dopants. Exptl. outcomes indicated that the addn. of Co-dopants improved the catalytic potential of CaO NPs. Al (4%)/St-doped CaO NPs expressed a significant redn. of methylene blue in a basic environment. The max. bactericidal performance was obsd. as 10.25 mm and 4.95 mm in the inhibition zone against S. aureus and E. coli, resp., after the addn. of Al and St in CaO.
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Mustajab, M.; Ikram, M.; Haider, A.; Ul-Hamid, A.; Nabgan, W.; Haider, J. Promising performance of polyvinylpyrrolidone doped bismuth oxyiodide quantum dots for antibacterial and catalytic applications. Appl. Nanosci. 2022, 12, 2621– 2633, DOI: 10.1007/s13204-022-02547-x
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Promising performance of polyvinylpyrrolidone-doped bismuth oxyiodide quantum dots for antibacterial and catalytic applications
Mustajab, Muhammad; Ikram, Muhammad; Haider, Ali; Ul-Hamid, Anwar; Nabgan, Walid; Haider, Junaid; Ghaffar, Rabia; Shahzadi, Anum; Ghaffar, Abdul; Saeed, Aamer
Applied Nanoscience (2022), 12 (9), 2621-2633CODEN: ANPACY; ISSN:2190-5517. (Springer GmbH)
Abstr.: In the present research study, the co-pptn. method was used to obtain novel bismuth oxyiodide quantum dots (BiOI QDs) with incorporation of various concns. (3, 6 and 9%) of polyvinylpyrrolidone (PVP) as a dopant. The no. of characterizations was employed to check the structural, morphol. and optical properties of prepd. samples. The hexagonal structure of BiOI has been confirmed by using x-ray diffraction (XRD) investigation. In addn., with increasing dopant concn. significant decreased in crystallite size was obsd. as 44.5, 19.9, 25.8 and 23.2 nm, while cryst. nature of synthesized QDs was confirmed by bright circular rings patterns of SAED. Micrographs of QDs were obtained using transmission electron microscope (TEM), and interlayer d-spacing was calcd. using HRTEM anal. FTIR spectra have been utilized to establish the existence of functional groups in addn. to recording the vibrational characteristic peak of BiOI. The bandgap energy increased gradually upon doping in the range of 2.86-2.93 eV. The dye degrdn. of toxic methylene blue (MB) has been examd. by applying doped and host BiOI nanocatalyst in the appearance of sodium borohydride (NaBH4). Dye elimination was found increasing with dopant concn. as 9% PVP-doped BiOI explored as a superior catalyst providing high MB degrdn. rate 99.50% in basic medium within seconds. Addnl., the antibacterial activity was tested against staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) pathogens; significant inhibition zone was measured against S. aureus bacteria as 4.60 mm.
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Zhao, Y.; Kang, S.; Qin, L.; Wang, W.; Zhang, T.; Song, S.; Komarneni, S. Self-assembled gels of Fe-chitosan/montmorillonite nanosheets: dye degradation by the synergistic effect of adsorption and photo-Fenton reaction. Chem. Eng. J. 2020, 379, 122322 DOI: 10.1016/j.cej.2019.122322
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Self-assembled gels of Fe-chitosan/montmorillonite nanosheets: Dye degradation by the synergistic effect of adsorption and photo-Fenton reaction
Zhao, Yunliang; Kang, Shichang; Qin, Lei; Wang, Wei; Zhang, Tingting; Song, Shaoxian; Komarneni, Sridhar
Chemical Engineering Journal (Amsterdam, Netherlands) (2020), 379 (), 122322CODEN: CMEJAJ; ISSN:1385-8947. (Elsevier B.V.)
Self-assembled gel of Fe-chitosan/montmorillonite nanosheets (Fe-CS/MMTNS) was prepd. for elimination of methylene blue (MB) under visible light in the presence of H2O2. The Fe-CS/MMTNS gel was characterized by FTIR, SEM-EDS, XPS and TG. The Fe-CS/MMTNS gel performed well in the removal of MB through the synergistic effect of adsorption and photo-Fenton reaction. Moreover, this gel worked efficiently under a wide range of pH conditions. This composite gel also showed effective reusability because the adsorption sites of the Fe-CS/MMTNS are continually reactivated through photo-Fenton degrdn. Addnl., the Fe-CS/MMTNS gel was found to be stable and the iron ions were hardly leached out because of the complexation between iron and chitosan (CS). The MB degrdn. occurred by two pathways: a part of MB was directly attacked by reactive radicals and gradually converted into inorg. substances while another part of MB was firstly adsorbed by Fe-CS/MMTNS gel and then degraded by reactive radicals.
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Lahive, E.; Jurkschat, K.; Shaw, B. J.; Handy, R. D.; Spurgeon, D. J.; Svendsen, C. Toxicity of cerium oxide nanoparticles to the earthworm Eisenia fetida: subtle effects. Environ. Chem. 2014, 11, 268– 278, DOI: 10.1071/EN14028
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Toxicity of cerium oxide nanoparticles to the earthworm Eisenia fetida: subtle effects
Lahive, Elma; Jurkschat, Kerstin; Shaw, Benjamin J.; Handy, Richard D.; Spurgeon, David J.; Svendsen, Claus
Environmental Chemistry (2014), 11 (3), 268-278CODEN: ECNHAA; ISSN:1449-8979. (CSIRO Publishing)
Environmental context This study investigates the toxicity of cerium oxide nanoparticles to earthworms, key organisms in soil ecosystems. Cerium oxide did not affect survival or reprodn. of the earthworms but did exert histol. changes. We conclude that current soil guidelines, based simply on metal toxicity, appear to adequately protect against cerium exposure risk, at least for earthworms. Abstr. The toxicity of cerium oxide (CeO2) nanoparticles (NPs) in soils is largely unknown. This study aimed to investigate the toxicity of three different CeO2 NPs to the earthworm, Eisenia fetida, for effects on survival (at day 28) and reprodn. (at day 56), as well as bioaccumulation and histopathol. effects. Eisenia fetida were exposed in std. Lufa 2.2 soil to three CeO2 NPs of different size ranges (5-80nm), one larger particle (300nm) and a cerium salt (ammonium cerium nitrate) over an exposure range from 41-10000mgCekg-1. Survival and reprodn. were not affected by the four CeO2 particles, even at the highest exposure concn. tested. Alternatively, 10000mgCekg-1 cerium salt affected survival and reprodn.; Median lethal concn. (LC50) and effective concn. (EC50) values were 317.8 and 294.6mgCekg-1. Despite a lack of toxic effect from the different forms of CeO2 particles, there was a dose-dependent increase in cerium in the organisms at all exposure concns., and for all material types. Earthworms exposed to CeO2 particles had higher concns. of total cerium compared to those exposed to ionic cerium, but without exhibiting the same toxic effect. Histol. observations in earthworms exposed to the particulate forms of CeO2 did, however, show cuticle loss from the body wall and some loss of gut epithelium integrity. The data suggest that that CeO2 NPs do not affect survival or reprodn. in E. fetida over the std. test period. However, there were histol. changes that could indicate possible deleterious effects over longer-term exposures.
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Kızılkonca, E.; Torlak, E.; Erim, F. B. Preparation and characterization of antibacterial nano cerium oxide/chitosan/hydroxyethylcellulose/polyethylene glycol composite films. Int. J. Biol. Macromol. 2021, 177, 351– 359, DOI: 10.1016/j.ijbiomac.2021.02.139
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Preparation and characterization of antibacterial nano cerium oxide/chitosan/hydroxyethylcellulose/polyethylene glycol composite films
Kizilkonca, Ezgi; Torlak, Emrah; Erim, F. Bedia
International Journal of Biological Macromolecules (2021), 177 (), 351-359CODEN: IJBMDR; ISSN:0141-8130. (Elsevier B.V.)
Due to the rapidly increasing biol. applications and antibacterial properties of versatile nano cerium oxide particles, the effects of these particles on chitosan-based films were investigated. Chitosan-based composite films with and without cerium oxide nanoparticles (NPs) were prepd. by a casting method. Hydroxyethylcellulose (HEC) was used for the flexibility of films, and polyethylene glycol (PEG) was used as a plasticizer in the blending stage of film prepn. Characterizations of films were done by Fourier transform IR spectroscopy (FTIR), thermogravimetric analyzer (TGA), and dynamic mech. analyzer (DMA). Cerium oxide nanoparticle incorporation enhanced the antibacterial activity of chitosan-based films against Escherichia coli and Staphylococcus aureus. This composite film is proposed as packaging or coating material because of its flexibility, antibacterial efficacy, and good mech. strength.
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Kalaycıoğlu, Z.; Kahya, N.; Adımcılar, V.; Kaygusuz, H.; Torlak, E.; Akın-Evingür, G.; Erim, F. B. Antibacterial nano cerium oxide/chitosan/cellulose acetate composite films as potential wound dressing. Eur. Polym. J. 2020, 133, 109777 DOI: 10.1016/j.eurpolymj.2020.109777
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Antibacterial nano cerium oxide/chitosan/cellulose acetate composite films as potential wound dressing
Kalaycioglu, Zeynep; Kahya, Nilay; Adimcilar, Veselina; Kaygusuz, Hakan; Torlak, Emrah; Akin-Evingur, Gulsen; Erim, F. Bedia
European Polymer Journal (2020), 133 (), 109777CODEN: EUPJAG; ISSN:0014-3057. (Elsevier Ltd.)
Novel chitosan and cellulose acetate polymer composites with nanosized cerium oxide were prepd. as potential wound dressing materials. Chitosan and cellulose acetate are natural polymer derivs. with biocompatible properties. Both polymers can be dissolved in formic acid. The polymer composite was formed by solvent-casting method. The formed films were not sol. in water. In order to improve antibacterial, thermal, and mech. properties of the composite material, films were loaded with nanosized cerium oxide. Films were characterized with thermogravimetric, SEM with energy-dispersive X-ray spectroscopy, mech., UV-visible light transmittance, water soly., pH, moisture content, water vapor transmission rate, swelling, and antibacterial tests. The phys. properties and antibacterial characteristics of the films are promising for further research as a potential wound covering material.
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Kızılkonca, E.; Erim, F. B. Development of anti-aging and anticorrosive nanoceria dispersed alkyd coating for decorative and industrial purposes. Coatings 2019, 9, 610, DOI: 10.3390/coatings9100610
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Development of anti-aging and anticorrosive nanoceria dispersed alkyd coating for decorative and industrial purposes
Kizilkonca, Ezgi; Erim, F. Bedia
Coatings (2019), 9 (10), 610CODEN: COATED; ISSN:2079-6412. (MDPI AG)
This study focuses on nano cerium oxide particles as alternative additives in solvent-based alkyd coatings in order to improve anticorrosive and anti-aging properties. The paint samples were formulated with cerium oxide micro and nanoparticles, and the coating quality characteristics were compared with coating formulated with com. anticorrosive and UV-aging agents. Formulations were prepd. with 3 wt % com. anticorrosive agent as ref. material (RP), 3 wt % cerium oxide microparticles (CER1), 3 wt % and 1% cerium oxide nanoparticles (CER2 and CER3), resp. The basket milling technique with zirconium balls was used for the prepns. of coatings and characterizations were performed by Fourier transform IR spectroscopy (FTIR), thermogravimetric anal. (TGA), and contact angle measurements. Improvement in the anticorrosive properties was proven with electrochem. impedance spectroscopy (EIS) and accelerated salt spray tests based on ISO 4628 Evaluation of Degrdn. of Coatings. Furthermore, phys. and mech. tests were run according to std. test methods for coatings and reported. Results showed that cerium oxide particles provide anticorrosive, UV defender, and self-cleaning effects, besides excellent phys. resistance to alkyd coatings. The impact of cerium oxide nanoparticles was found to be stronger than those of the microparticles.
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Kaygusuz, H.; Erim, F. B. Biopolymer-assisted green synthesis of functional cerium oxide nanoparticles. Chem. Pap. 2020, 74, 2357– 2363, DOI: 10.1007/s11696-020-01084-7
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Biopolymer-assisted green synthesis of functional cerium oxide nanoparticles
Kaygusuz, Hakan; Erim, F. Bedia
Chemical Papers (2020), 74 (7), 2357-2363CODEN: CHPAEG; ISSN:1336-9075. (Springer International Publishing AG)
Cerium oxide nanoparticles were synthesized by thermal decompn. of cerium alginate biopolymer gel at 450° C, where alginate both acts as a precursor and a template. The synthesis is a green, facile and one-step method and the resulting nanoparticles have functionalized surface. The resulted material were characterized using X-ray diffraction for confirmation of cerium oxide, crystallite size anal. and grain size distribution. Transmission electron microscopy was used for the particle size detn., hydrodynamic size estn. was studied by dynamic light scattering and surface characteristics were analyzed using zeta potential measurements. Results show the presence of spherical particles with a size of < 5 nm. Having only a neg. surface charge in such a wide pH range will ensure that the behavior of obtained nanoparticles in different environments is predictable. Isoelec. point of the synthesized material is significantly different from non-functionalized cerium oxide, and indicates the surface functionality, which is an important property for biocompatibility.
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Kalaycıoğlu, Z.; Gecim, B.; Erim, F. B. Green synthesis of cerium oxide nanoparticles from turmeric and kinds of honey: Characterizations, antioxidant and photocatalytic dye degradation activities. Adv. Nat. Sci.: Nanosci. Nanotechnol. 2022, 13, 015016 DOI: 10.1088/2043-6262/ac5dc5
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Channei, D.; Nakaruk, A.; Phanichphant, S. Influence of graphene oxide on photocatalytic enhancement of cerium dioxide. Mater. Lett. 2017, 209, 43– 47, DOI: 10.1016/j.matlet.2017.07.109
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Influence of graphene oxide on photocatalytic enhancement of cerium dioxide
Channei, Duangdao; Nakaruk, Auppatham; Phanichphant, Sukon
Materials Letters (2017), 209 (), 43-47CODEN: MLETDJ; ISSN:0167-577X. (Elsevier B.V.)
Graphene oxide (GO) was prepd. by oxidizing purified natural flake graphite via modified Hummers method. The suspension of GO particles and cerium-based precursors were treated hydrothermally in order to prep. CeO2/GO composites. The disappearance of the [0 0 1] GO diffraction peak was observable in the XRD pattern for CeO2/GO composites because the crystal growth of CeO2 between the interlayer of GO destroyed the regular layer stacking of GO phase. However XPS spectra of O 1 s core level and oxygen vacancies defect in CeO2 caused the decrease in degree of crystallinity. Composite of CeO2 with GO not only prevented the formation of extrinsic vacancies in the oxygen sub-lattice, but also prevented the switching from the major photoactive species Ce4+ to Ce3+. The photocatalytic activity measurements demonstrated that the CeO2/GO composites exhibited much higher photocatalytic activity than CeO2 for degrdn. of methylene blue (MB) under visible light irradn. The enhancement of photocatalytic activity could be attributed to the excellently elevated absorption ability for the MB dye through π-π conjugation. As reported in PL results, the effective inhibition of the recombination of photogenerated electron-hole pairs due to the charge interaction between CeO2 and GO.
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Channei, D.; Chansaenpak, K.; Phanichphant, S.; Jannoey, P.; Khanitchaidecha, W.; Nakaruk, A. Synthesis and characterization of WO₃/CeO₂ heterostructured nanoparticles for photodegradation of indigo carmine dye. ACS Omega 2021, 6, 19771– 19777, DOI: 10.1021/acsomega.1c02453
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Synthesis and Characterization of WO3/CeO2 Heterostructured Nanoparticles for Photodegradation of Indigo Carmine Dye
Channei, Duangdao; Chansaenpak, Kantapat; Phanichphant, Sukon; Jannoey, Panatda; Khanitchaidecha, Wilawan; Nakaruk, Auppatham
ACS Omega (2021), 6 (30), 19771-19777CODEN: ACSODF; ISSN:2470-1343. (American Chemical Society)
WO3/CeO2 heterostructured nanocomposites contg. different WO3 ratios (0.1, 0.3, 0.5, and 1.0%) were synthesized by a pptn. method. The coupling of CeO2 and WO3 with a high sp. surface area noticeably enhanced the photocatalytic activity of indigo carmine (IC) degrdn. under visible-light irradn. The degrdn. rate consts. (k) of 0.5% WO3/CeO2 nanocomposites reached 4 and 5 times higher than those of CeO2 and WO3, resp. Regarding the exptl. results, the XRD patterns of the CeO2 spherical nanoparticles and rod-shaped WO3 were assigned to the cubic fluorite and orthorhombic phase structures, resp. The increasing photocatalytic activity of nanocomposite samples could be attributed to the heterojunction of the photocatalysts with efficient charge sepn. and strong oxidative ability, which were confirmed by the photoluminescence spectra and diffuse reflectance spectrometry. The staggered heterojunction of the nanocomposite promoted efficient electron transfer and suppressed the recombination of photogenerated electrons and holes during the process.
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Moradi, B.; Nabiyouni, G.; Ghanbari, D. Rapid photo-degradation of toxic dye pollutants: green synthesis of mono-disperse Fe₃O₄-CeO₂ nanocomposites in the presence of lemon extract. J. Mater. Sci.: Mater. Electron. 2018, 29, 11065– 11080, DOI: 10.1007/s10854-018-9189-7
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Rapid photo-degradation of toxic dye pollutants: green synthesis of mono-disperse Fe3O4-CeO2 nanocomposites in the presence of lemon extract
Moradi, Banafsheh; Nabiyouni, Gholamreza; Ghanbari, Davood
Journal of Materials Science: Materials in Electronics (2018), 29 (13), 11065-11080CODEN: JSMEEV; ISSN:0957-4522. (Springer)
Fe3O4 nanoparticles were first synthesized via a fast pptn. method. CeO2 and Fe3O4-CeO2 nanocomposites then were prepd. using hydrothermal method with a green procedure in the presence of lemon ext. The effect of time, pH and applied magnetic field on the size and shape of nanostructures were investigated. The prepd. products were characterized using X-ray diffraction, SEM, and Fourier transform IR spectroscopy. Vibrating sample magnetometer was used to study the magnetic property of the products. The results illustrated super-paramagnetic behavior of Fe3O4 nanoparticles. The photo-catalytic behavior of Fe3O4-CeO2 nanocomposites was evaluated using the degrdn. of two azo dyes under UV light irradn. The results show that the prepd. nanocomposites have potential application for magnetic and photo-catalytic performance.
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Kusmierek, E. A CeO₂ semiconductor as a photocatalytic and photo electrocatalytic material for the remediation of pollutants in industrial wastewater: A review. Catalysts 2020, 10, 1435, DOI: 10.3390/catal10121435
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A CeO2 semiconductor as a photocatalytic and photoelectrocatalytic material for the remediation of pollutants in industrial wastewater: a review
Kusmierek, Elzbieta
Catalysts (2020), 10 (12), 1435CODEN: CATACJ; ISSN:2073-4344. (MDPI AG)
A review. The direct discharge of industrial wastewater into the environment results in serious contamination. Photocatalytic treatment with the application of sunlight and its enhancement by coupling with electrocatalytic degrdn. offers an inexpensive and green technol. enabling the total removal of refractory pollutants such as surfactants, pharmaceuticals, pesticides, textile dyes, and heavy metals, from industrial wastewater. Among metal oxide-semiconductors, cerium dioxide is one of the photocatalysts most commonly applied in pollutant degrdn. CeO2 exhibits promising photocatalytic activity. Nonetheless, the position of conduction bands and valence bands in CeO2 limits its application as an efficient photocatalyst utilizing solar energy. Its photocatalytic activity in wastewater treatment can be improved by various modification techniques, including changes in morphol., doping with metal cation dopants and non-metal dopants, coupling with other semiconductors, and combining it with carbon supporting materials. This paper presents a general overview of CeO2 application as a single or composite photocatalyst in the treatment of various pollutants. The photocatalytic characteristics of CeO2 and its composites are described. The main photocatalytic reactions with the participation of CeO2 under UV and VIS irradn. are presented. This review summarizes the existing knowledge, with a particular focus on the main exptl. conditions employed in the photocatalytic and photoelectrocatalytic degrdn. of various pollutants with the application of CeO2 as a single and composite photocatalyst.
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Yadav, S.; Raman, A. P. S.; Meena, H.; Goswami, A. G.; Vinod Kumar, B.; Jain, P. An update on graphene oxide: applications and toxicity. ACS Omega 2022, 7, 35387– 35445, DOI: 10.1021/acsomega.2c03171
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An Update on Graphene Oxide: Applications and Toxicity
Yadav, Sandeep; Singh Raman, Anirudh Pratap; Meena, Harshvardhan; Goswami, Abhay Giri; Bhawna; Kumar, Vinod; Jain, Pallavi; Kumar, Gyanendra; Sagar, Mansi; Rana, Devendra Kumar; Bahadur, Indra; Singh, Prashant
ACS Omega (2022), 7 (40), 35387-35445CODEN: ACSODF; ISSN:2470-1343. (American Chemical Society)
A review. Graphene Oxide (GO) has attracted much attention in past few years because of its interesting and promising elec., thermal, mech., and structural properties. These properties can be altered as GO can be readily functionalized. Brodie synthesized the GO in 1859 by reacting graphite with KClO3 in the presence of fuming HNO3; the reaction took 3-4 days to complete at 333 K. Since then, various schemes have been developed to reduce the reaction time, increase the yield and minimize the release of toxic byproducts (NO2 and N2O4). Modified Hummers method has been widely accepted to produce GO in bulk. Due to its versatile characteristics, GO has wide range of applications in different fields like tissue engineering, photocatalytic, catalysis, and biomedical applications. Its porous structure is considered appropriate for tissue and organ regeneration. Various branches of tissue engineering are being extensively explored, such as bone, neural, dentistry, cartilage and skin tissue engineering. The bandgap of GO can be easily tuned and therefore, it has a wide range of photocatalytic applications as well; degrdn. of org. contaminants, hydrogen generation and CO2 redn. etc. GO could be a potential nanocarrier in drug delivery systems, gene delivery, biol. sensing and antibacterial nanocomposites due to its large surface area and high d., as it is highly functionalized with oxygen contg. functional groups. GO or its composites are found toxic to various biol. species and is also discussed in this review. It has been obsd. that SOD and ROS levels gradually increase over a period after GO is introduced in the biol. systems. Hence, GO at specific concns. is toxic for various species like earthworms, Chironomus riparius, Zebrafish etc.
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Channei, D.; Nakaruk, A.; Phanichphant, S. Influence of graphene oxide on photocatalytic enhancement of cerium dioxide. Mater. Lett. 2017, 209, 43– 47, DOI: 10.1016/j.matlet.2017.07.109
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Influence of graphene oxide on photocatalytic enhancement of cerium dioxide
Channei, Duangdao; Nakaruk, Auppatham; Phanichphant, Sukon
Materials Letters (2017), 209 (), 43-47CODEN: MLETDJ; ISSN:0167-577X. (Elsevier B.V.)
Graphene oxide (GO) was prepd. by oxidizing purified natural flake graphite via modified Hummers method. The suspension of GO particles and cerium-based precursors were treated hydrothermally in order to prep. CeO2/GO composites. The disappearance of the [0 0 1] GO diffraction peak was observable in the XRD pattern for CeO2/GO composites because the crystal growth of CeO2 between the interlayer of GO destroyed the regular layer stacking of GO phase. However XPS spectra of O 1 s core level and oxygen vacancies defect in CeO2 caused the decrease in degree of crystallinity. Composite of CeO2 with GO not only prevented the formation of extrinsic vacancies in the oxygen sub-lattice, but also prevented the switching from the major photoactive species Ce4+ to Ce3+. The photocatalytic activity measurements demonstrated that the CeO2/GO composites exhibited much higher photocatalytic activity than CeO2 for degrdn. of methylene blue (MB) under visible light irradn. The enhancement of photocatalytic activity could be attributed to the excellently elevated absorption ability for the MB dye through π-π conjugation. As reported in PL results, the effective inhibition of the recombination of photogenerated electron-hole pairs due to the charge interaction between CeO2 and GO.
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Nemati, F.; Rezaie, M.; Tabesh, H.; Eid, K.; Xu, G.; Ganjali, M. R. Cerium functionalized graphene nano-structures and their applications; A review. Environ. Res. 2022, 208, 112685 DOI: 10.1016/j.envres.2022.112685
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Cerium functionalized graphene nano-structures and their applications; A review
Nemati, Fatemeh; Rezaie, Maryam; Tabesh, Hadi; Eid, Kamel; Xu, Guobao; Ganjali, Mohammad Reza; Hosseini, Morteza; Karaman, Ceren; Erk, Nevin; Show, Pau-Loke; Zare, Najmeh; Karimi-Maleh, Hassan
Environmental Research (2022), 208 (), 112685CODEN: ENVRAL; ISSN:0013-9351. (Elsevier Inc.)
A review. Graphene-based nanomaterials with remarkable properties, such as good biocompatibility, strong mech. strength, and outstanding elec. cond., have dramatically shown excellent potential in various applications. Increasing surface area and porosity percentage, improvement of adsorption capacities, redn. of adsorption energy barrier, and also prevention of agglomeration of graphene layers are the main advantages of functionalized graphene nanocomposites. On the other hand, Cerium nanostructures with remarkable properties have received a great deal of attention in a wide range of fields; however, in some cases low cond. limits their application in different applications. Therefore, the combination of cerium structures and graphene networks has been widely invesitaged to improve properties of the composite. In order to have a comprehensive information of these nanonetworks, this research reviews the recent developments in cerium functionalized graphene derivs. (graphene oxide (GO), reduced graphene oxide (RGO), and graphene quantum dot (GQD) and their industrial applications. The applications of functionalized graphene derivs. have also been successfully summarized. This systematic review study of graphene networks decorated with different structure of Cerium have potential to pave the way for scientific research not only in field of material science but also in fluorescent sensing, electrochem. sensing, supercapacitors, and catalyst as a new candidate.
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Moztahida, M.; Lee, D. S. Photocatalytic degradation of methylene blue with P25/graphene/polyacrylamide hydrogels: Optimization using response surface methodology. J. Hazard. Mater. 2020, 400, 123314 DOI: 10.1016/j.jhazmat.2020.123314
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Photocatalytic degradation of methylene blue with P25/graphene/polyacrylamide hydrogels: Optimization using response surface methodology
Moztahida, Mokrema; Lee, Dae Sung
Journal of Hazardous Materials (2020), 400 (), 123314CODEN: JHMAD9; ISSN:0304-3894. (Elsevier B.V.)
An environment-friendly hydrogel was synthesized by entrapping Degussa P25 on the surface of a reduced graphene oxide (rGO)-polyacrylamide (PAM) matrix. The PAM content of the P25-rGO-PAM (PGP) hydrogel considerably influenced the adsorption and photocatalytic degrdn. of methylene blue (MB), and the optimal PAM content was 10% (w/v). Furthermore, rGO not only enhanced the adsorption capacity of the hydrogel by increasing the surface area but also increased the photodegrdn. efficiency synergistically by seperating electron-hole pairs. The reaction kinetic const. for MB degrdn. by the hydrogel was 0.0276 min-1, which was three and five times the reaction kinetic consts. of P25-PAM and rGO-PAM hydrogels, resp. The synthesized PGP showed high stability and its MB degrdn. efficiency was considerably high up to five consecutive cycles under UV-irradn. The eco-friendly nature of the hydrogel was evaluated on the basis of bacterial inactivation, and the treated water was found to be safe for use. Three key operating parameters (initial MB concn., temp., and pH) were optimized for maximizing MB removal using a response surface methodol. The complete MB removal efficiency was obtained for the optimal conditions of pH 9.4, a temp. of 31.2°C, and an initial MB concn. of 5.2 mg/L.
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Mansurov, R. R.; Safronov, A. P.; Lakiza, N. V.; Beketov, I. V. Photocatalytic activity of titanium dioxide nanoparticles immobilized in the polymer network of polyacrylamide hydrogel. Russ. J. Appl. Chem. 2017, 90, 1712– 1721, DOI: 10.1134/S1070427217100238
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Photocatalytic Activity of Titanium Dioxide Nanoparticles Immobilized in Polymer Network of Polyacrylamide Hydrogel
Mansurov, R. R.; Safronov, A. P.; Lakiza, N. V.; Beketov, I. V.
Russian Journal of Applied Chemistry (2017), 90 (10), 1712-1721CODEN: RJACEO; ISSN:1070-4272. (Pleiades Publishing, Ltd.)
Composite hydrogels based on polyacrylamide immobilized nanoparticles of com. (P25 brand) titanium dioxide and of titanium dioxide nanoparticles prepd. by elec. explosion of a wire were synthesized. The enthalpy of interaction at the polyacrylamide/TiO2 interface was detd. by microcalorimetry using the thermochem. cycle method. Interaction of polyacrylamide polymer chains with the surface of TiO2 nanoparticles is energetically unfavorable. The absence of interactions between the hydrogel polymer network and surface of TiO2 nanoparticles favors manifestation of the UV-induced photocatalytic activity of TiO2 nanoparticles immobilized in the hydrogel. Immobilization in the polyacrylamide hydrogel matrix decreases the photocatalytic activity of P25 brand TiO2 nanoparticles, but does not affect the photocatalytic activity of titanium dioxide nanoparticles prepd. by the elec. explosion method. The photocatalytic activity of TiO2 nanoparticles immobilized in the bulk of polyacrylamide hydrogel evaluated by the decompn. of Methyl orange dye is controlled by the diffusion rate of the dye mols. into the bulk of the hydrogel and depends also on the aggregation of TiO2 nanoparticles in the hydrogel matrix.
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Kazemi, F.; Mohamadnia, Z.; Kaboudin, B.; Karimi, Z. Photodegradation of methylene blue with a titanium dioxide/polyacrylamide photocatalyst under sunlight. J. Appl. Polym. Sci. 2016, 133, 43386 DOI: 10.1002/app.43386
Google Scholar
There is no corresponding record for this reference.
37
Pasikhani, J. V.; Gilani, N.; Pirbazari, A. E. Improvement the wastewater purification by TiO₂ nanotube arrays: The effect of etching-step on the photo-generated charge carriers and photocatalytic activity of anodic TiO₂ nanotubes. Solid State Sci. 2018, 84, 57– 74, DOI: 10.1016/j.solidstatesciences.2018.08.003
Google Scholar
37
Improvement the wastewater purification by TiO2 nanotube arrays: The effect of etching-step on the photo-generated charge carriers and photocatalytic activity of anodic TiO2 nanotubes
Pasikhani, Javad Vahabzadeh; Gilani, Neda; Pirbazari, Azadeh Ebrahimian
Solid State Sciences (2018), 84 (), 57-74CODEN: SSSCFJ; ISSN:1293-2558. (Elsevier Masson SAS)
The current study demonstrates how the etching step in anodization process effects on the photocatalytic activity of TiO2 nanotubes. In this regard, the TiO2 nanotubes were made by one-step and two-step anodization process on two different substrates Ti and etched-Ti foils, resp. The results revealed that two-step anodization process is a beneficial way to prep. highly well-organized structure and regular surface. The two-step anodization by an enhancement in the fluoride ions diffusion led to a decrease in nanotubes' porosity and an increment in the nanotubes' surface area, a factor of roughness, and the ratio of length to diam., resp. As a consequence of the improvement in geometrical properties, the two-step TiO2 nanotubes led to the intensification of photocurrent d. (from 0.383 to 0.677 mA cm-2) and photoconversion efficiency (from 0.18% to 0.29%) in comparison with the one-step nanotubes, resp. Further, a synergetic impact of the photoelectrochem. measurement and photocatalytic process was obsd. The degrdn. efficiencies of 2,4-dichlorophenol by two-step nanotubes increased from 47 to 55% under visible light, and from 58 to 72% under UV irradn., which it was attributed to more light harvesting, more photo-generated electrons, higher sepn. efficiency and improvement in geometrical properties.
38
Godwin Uranta, K.; Rezaei-Gomari, S.; Russell, P.; Hamad, F. Studying the effectiveness of polyacrylamide (PAM) application in hydrocarbon reservoirs at different operational conditions. Energies 2018, 11, 2201, DOI: 10.3390/en11092201
Google Scholar
There is no corresponding record for this reference.
39
Luceño-Sánchez, J. A.; Maties, G.; Gonzalez-Arellano, C.; Díez-Pascual, A. M. Synthesis and characterization of graphene oxide derivatives via functionalization reaction with hexamethylene diisocyanate. 2019, 3, 8. 10.3390/IOCN_2018-1-05485.
Google Scholar
There is no corresponding record for this reference.
40
Abid; Sehrawat, P.; Islam, S. S.; Mishra, P.; Ahmad, S. Reduced graphene oxide (rGO) based wideband optical sensor and the role of temperature, defect states and quantum efficiency. Sci. Rep. 2018, 8, 3537 DOI: 10.1038/s41598-018-21686-2
Google Scholar
40
Reduced graphene oxide (rGO) based wideband optical sensor and the role of Temperature, Defect States and Quantum Efficiency
Abid; Sehrawat Poonam; Islam S S; Mishra Prabhash; Ahmad Shahab
Scientific reports (2018), 8 (1), 3537 ISSN:.
We report a facile and cost-effective approach to develop self-standing reduced Graphene Oxide (rGO) film based optical sensor and its low-temperature performance analysis where midgap defect states play a key role in tuning the crucial sensor parameters. Graphite oxide (GO) is produced by modified Hummers' method and reduced thermally at 250 °C for 1 h in Argon atmosphere to obtain rGO. Self-standing rGO film is prepared via vacuum filtration. The developed film is characterized by HRTEM, FESEM, Raman, and XRD techniques. The developed sensor exhibits highest sensitivity towards 635 nm illumination wavelength, irrespective of the operating temperature. For a given excitation wavelength, photoresponse study at low temperature (123K-303K) reveals inverse relationship between sensitivity and operating temperature. Highest sensitivity of 49.2% is obtained at 123 K for 635 nm laser at power density of 1.4 mW/mm(2). Unlike sensitivity, response- and recovery-time demonstrate directly proportional dependence with operating temperature. Power dependent studies establish linear relation between power-density and sensitivity, and a safe limit beyond which sample heating prolongs the recovery time. Wavelength-dependent studies shows that proposed sensor can efficiently operate from visible to near NIR region. To the best of our knowledge such rGO based optical sensor performance at low temperature had not been reported earlier.
41
Kickelbick, G. Hybrid Materials: Synthesis, Characterization and Applications; Wiley-VCH: Weinheim, 2007.
Google Scholar
There is no corresponding record for this reference.
42
Pouretedal, H. R.; Kadkhodaie, A. Synthetic CeO₂ nanoparticle catalysis of methylene blue photodegradation: kinetics and mechanism. Chin. J. Catal. 2010, 31, 1328– 1334, DOI: 10.1016/S1872-2067(10)60121-0
Google Scholar
There is no corresponding record for this reference.
43
Kusuma, K. B.; Manju, M.; Ravikumar, C. R.; Raghavendra, N.; Shilpa Amulya, M. A.; Nagaswarupa, H. P. Photocatalytic degradation of methylene blue and electrochemical sensing of paracetamol using cerium oxide nanoparticles synthesized via sonochemical route. Appl. Surf. Sci. 2022, 11, 100304 DOI: 10.1016/j.apsadv.2022.100304
Google Scholar
There is no corresponding record for this reference.
44
Sehar, S.; Naz, I.; Rehman, A.; Sun, W.; Alhewairini, S. S.; Zahid, M. N.; Younis, A. Shape-controlled synthesis of cerium oxide nanoparticles for efficient dye photodegradation and antibacterial activities. Appl. Organomet. Chem. 2021, 35, e6069 DOI: 10.1002/aoc.6069
Google Scholar
44
Shape-controlled synthesis of cerium oxide nanoparticles for efficient dye photodegradation and antibacterial activities
Sehar, Shama; Naz, Iffat; Rehman, Abdul; Sun, Wuyang; Alhewairini, Saleh S.; Zahid, Muhammad Nauman; Younis, Adnan
Applied Organometallic Chemistry (2021), 35 (1), e6069CODEN: AOCHEX; ISSN:0268-2605. (John Wiley & Sons Ltd.)
Herein, two-shaped cerium oxide nanoparticles (NPs), i.e., spherical and cubical, were synthesized through hydrothermal approach by tuning reaction temps. The morphol. and structural and chem. compn. of both samples were characterized by transmission electron microscopy (TEM), high-resoln. TEM (HRTEM), X-ray diffraction (XRD), and XPS, resp. Both types of NPs were subjected to photodegrdn. of industrial dye, methylene blue, under dark, sunlight, and UV irradn., and their recyclability and reusability were also assessed. Besides, the effect of pH, concn. of NPs, and dye on degradability was also analyzed. The cubical-shaped NPs demonstrated superior degrdn. of ∼70% under UV irradn. than the spherical ones (<50%). The antibacterial activities of both NPs were also examd., and cubical-shaped NPs were found to exhibit superior antimicrobial potential (zone of inhibition [ZOI]: 25.75 ± 0.25, 18.83 ± 0.76, 15.75 ± 0.66, and 15.75 ± 0.25 mm) in comparison with the spherical ones (ZOI: 19.41 ± 0.94, 14.25 ± 0.66, 12.58 ± 1.01, and 9.91 ± 1.01 nm) for Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Staphylococcus aureus resp. with reduced growth and viable count. This difference in performance may be attributed to the higher surface areas of cubical-shaped NPs and higher content of oxygen vacancies. The results presented in this study suggest that cubical NPs are excellent candidates for treating industrial wastewater with greater reproducibility. Moreover, they can be used as active growth inhibitors against different microorganisms and thus can be extremely useful in developing medical devices and to design various antimicrobial systems.
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Murugan, R.; Kashinath, L.; Subash, R.; Sakthivel, P.; Byrappa, K.; Rajendran, S.; Ravi, G. Pure and alkaline metal ion (Mg, Ca, Sr, Ba) doped cerium oxide nanostructures for photo degradation of methylene blue. Mater. Res. Bull. 2018, 97, 319– 325, DOI: 10.1016/j.materresbull.2017.09.026
Google Scholar
45
Pure and alkaline metal ion (Mg, Ca, Sr, Ba) doped cerium oxide nanostructures for photo degradation of methylene blue
Murugan, R.; Kashinath, L.; Subash, R.; Sakthivel, P.; Byrappa, K.; Rajendran, S.; Ravi, G.
Materials Research Bulletin (2018), 97 (), 319-325CODEN: MRBUAC; ISSN:0025-5408. (Elsevier Ltd.)
Pure and alk. metal ion (Mg, Ca, Sr, Ba) doped Cerium oxide nanostructures were successfully synthesized by hydrothermal method. The structural, optical and compositional studies of the prepd. nanoparticles were undertaken by X-ray diffraction (XRD), Fourier transform IR spectroscopy (FTIR), photoluminescence (PL), Raman, XPS and TEM analyses. The photocatalytic activity of prepd. nanoparticles was analyzed using methylene blue dye. XRD pattern reveals that the prepd. nanoparticles are polycryst. nature and there is no any byproduct related peaks were obsd. for the doped samples. The incorporation of dopants into the CeO2 nanoparticles was confirmed through PL, Raman and XPS spectra. The enhanced photocatalytic activity for the alk. metal doped samples was obsd. compared to pure cerium oxide nanoparticles.
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Neelgund, G. M.; Oki, A. Graphene-coupled ZnO: A robust NIR-induced catalyst for rapid photo-oxidation of cyanide. ACS Omega 2017, 2, 9095– 9102, DOI: 10.1021/acsomega.7b01398
Google Scholar
46
Graphene-Coupled ZnO: A Robust NIR-Induced Catalyst for Rapid Photo-Oxidation of Cyanide
Neelgund, Gururaj M.; Oki, Aderemi
ACS Omega (2017), 2 (12), 9095-9102CODEN: ACSODF; ISSN:2470-1343. (American Chemical Society)
Herein, we report the modulation of ZnO for enhancement of its ability toward plasmonic absorption of near-IR (NIR) photons through coupling of graphene (GR). The reported modification led GR-ZnO to be a promising photocatalyst by the complete removal of poisonous and nonvolatile potassium cyanide from water. The photocatalytic degrdn. of cyanide was revealed by exposing it to NIR laser radiation and comparing with the rate of UV, visible, and sunlight using their apparent reaction rate consts. derived from the Langmuir-Hinshelwood simulation, physicochem. The heteronanostructured GR-ZnO promoted rapid photo-oxidn. of cyanide under illumination with NIR laser radiation rather than UV, visible, and sunlight. It was assessed that the photothermal effect (PTE) is the main cause for higher catalytic efficiency of GR-ZnO in the presence of NIR radiations. Except for the NIR radiations, GR-ZnO does not show any indication of PTE by irradiating with UV, visible, or sunlight. On account of its significance, the PTE of GR-ZnO in KCN soln. was evaluated and compared with its individual components viz., GR and ZnO upon exposure to a 980 nm laser radiation system. Furthermore, it has been revealed that the PTE of GR-ZnO was proportional to its concn. In addn. to its effectiveness in the degrdn. of cyanide, GR-ZnO retained its special structure and exhibited an outstanding photostability after its repeated use in three successive cycles.

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Osama Saber, Chawki Awada, Asmaa M. Hegazy, Aya Osama, Nagih M. Shaalan, Adil Alshoaibi, Mostafa Osama. Controlling the Carbon Species to Design Effective Photocatalysts Based on Explosive Reactions for Purifying Water by Light. Catalysts 2025, 15 (1) , 96. https://doi.org/10.3390/catal15010096
Bashir Abubakar Abdulkadir, Muhammad Naim Mohd Rozi, Nur Husnina Norfairuzazuan, Nur Athya Mat Daud, Herma Dina Setiabudi. Improved Photodegradation of Methylene Blue Using Cost-Effective and Renewable Fe-Supported Fibrous Nano-silica from Palm Oil Fuel Ash. Topics in Catalysis 2024, 337 https://doi.org/10.1007/s11244-024-02035-2
Anjali, Aarti Gupta, Babita Tripathi, Mohit Sahni, Kuldeep Sharma, Nishant Ranjan, M. Z. A. Yahya, I. M. Noor, Soumya Pandit. Enhancing photocatalytic performance of Fe3O4 nanoparticles and Fe3O4@ZnO nanocomposites. Ionics 2024, 30 (12) , 8267-8279. https://doi.org/10.1007/s11581-024-05843-4
Muhammad Ikram, Ali Haider, Muhammad Bilal, Anwar Ul-Hamid, Souraya Goumri-Said, Mohammed Benali Kanoun, El Sayed Yousef, Salamat Ali. Investigating the catalytic and antibacterial behavior of cesium-doped MoO3 nanostructures against methylene blue dye and MDR E. coli with DFT analysis. Materials Today Sustainability 2024, 28 , 101031. https://doi.org/10.1016/j.mtsust.2024.101031
Fauzia, Mo Ahamad Khan, Mohd Chaman, Ameer Azam. Antibacterial and sunlight-driven photocatalytic activity of graphene oxide conjugated CeO2 nanoparticles. Scientific Reports 2024, 14 (1) https://doi.org/10.1038/s41598-024-54905-0
Alaa I. Khedr, Mohamed H. H. Ali. Eco-friendly fabrication of copper oxide nanoparticles using peel extract of Citrus aurantium for the efficient degradation of methylene blue dye. Scientific Reports 2024, 14 (1) https://doi.org/10.1038/s41598-024-79589-4
Keya Mandal, Dipti Das, Supriya Kumar Bose, Aparna Chaudhuri, Arpita Chakraborty, Sapna Mandal, Sabyasachi Ghosh, Swarup Roy. Spectroscopic approach to optimize the biogenic silver nanoparticles for photocatalytic removal of ternary dye mixture and ecotoxicological impact of treated wastewater. Scientific Reports 2024, 14 (1) https://doi.org/10.1038/s41598-024-82341-7
Win Thi Yein, Dong-Su Kim, Qun Wang. Interfacial Action of Co-Doped MoS2 Nanosheets on Directional Piezoelectric Catalytic Generation of Reactive Oxygen Species. 2024, 3. https://doi.org/10.3390/chemproc2024015003
Samara J. Cisneros-Trejo, Francisco Paraguay-Delgado, Arturo Hernández-Hernández, Juan C. Pantoja-Espinoza. Reusable Porous SiO2 for Methylene Blue Removal: A Study on Adsorption and Regeneration Cycles. Water, Air, & Soil Pollution 2024, 235 (11) https://doi.org/10.1007/s11270-024-07539-x
Mahkameh Amirbandeh, Seyed Morteza Zamir, François Lefort, Julien Crovadore, Bita Bakhshi. Response of biofilm structure to long-term exposure to CeO2 nanoparticles in a trickling bioreactor for the removal of phenol, nitrogen, and phosphorus. International Biodeterioration & Biodegradation 2024, 195 , 105880. https://doi.org/10.1016/j.ibiod.2024.105880
Ebtesam E Ateia, D Gawad, M M Arman. Core-shell nanomaterials based on La 2 FeCrO 6 coated with metal oxides for optical applications. Physica Scripta 2024, 99 (11) , 115933. https://doi.org/10.1088/1402-4896/ad80e6
Pooja Sharma, Vishal Virole, Tauseef Anwar, Om Kolekar, Anup A. Kale, Shilpa Chapadgaonkar, Ashish Yengantiwar, , . Nanomaterials mediated and biosorption-based photocatalytic treatment for efficient and rapid bioremediation of textile industry wastewater. 2024, 18. https://doi.org/10.1117/12.3044561
Hagar M. Mahdy, Yehia M. Abbas, Hend S. Magar, Rabeay Y. A. Hassan, El-shazly M. Duraia. Silver vanadate and cerium oxide decorated graphene oxide ternary heterostructure nanocomposites: structural, electrochemical, and optoelectrical properties. Journal of Materials Science: Materials in Electronics 2024, 35 (28) https://doi.org/10.1007/s10854-024-13439-x
Ahmed Farghaly, Eman Maher, Ali Gad, Haitham El-Bery. Synergistic photocatalytic degradation of methylene blue using TiO2 composites with activated carbon and reduced graphene oxide: a kinetic and mechanistic study. Applied Water Science 2024, 14 (10) https://doi.org/10.1007/s13201-024-02286-0
Cheng Zhang, Guangqi An, Yunxin Zhu, Xiang Sun, Guoping Chen, Yingnan Yang. Development of a sunlight adjustable parabolic trough reactor for 24-hour efficient photocatalytic wastewater treatment. Chemical Engineering Journal 2024, 497 , 154582. https://doi.org/10.1016/j.cej.2024.154582
Anjali Vijeata, Alastair W. Wark, Ganga Ram Chaudhary, Savita Chaudhary. Experimental and theoretical exploration of bactericidal and photo-catalytical activities of hierarchically porous AuNRs@CuO nanocomposite. Journal of Cleaner Production 2024, 476 , 143740. https://doi.org/10.1016/j.jclepro.2024.143740
Duha A. Kadhim, Muslim A. Abid, Wafaa M. Salih. Photocatalytic activity for degradation of methylene blue dye-mediated nanocomposite-copper oxide/graphene oxide preparation from blood solution via hydrothermal method with laser irradiation. Vacuum 2024, 228 , 113481. https://doi.org/10.1016/j.vacuum.2024.113481
, R. N. Mondal, S. Saha, . MoS2-CZTS: a 2D-3D nanocomposite to enhance the photocatalytic performance in degradation of methylene blue dye. Chalcogenide Letters 2024, 21 (10) , 771-783. https://doi.org/10.15251/CL.2024.2110.771
Yağmur Poyraz, Nisa Baltacı, Gana Hassan, Oubadah Alayoubi, Bengü Özuğur Uysal, Önder Pekcan. Composite Hydrogel of Polyacrylamide/Starch/Gelatin as a Novel Amoxicillin Delivery System. Gels 2024, 10 (10) , 625. https://doi.org/10.3390/gels10100625
Brijesh Pare, Roshni Joshi, Vijendra Singh Solanki, Neha Agarwal, Daoud Ali, Saud Alarifi, Virendra Kumar Yadav. Synthesis and characterisation of visible light-responsive Fe-doped BiOCl NPs and their application for the remediation of textile dye by LED irradiation. International Journal of Environmental Analytical Chemistry 2024, , 1-23. https://doi.org/10.1080/03067319.2024.2402078
Ghazal Oroumi, Amirhossein Hemmatzadeh, Karrar Hazim Salem, Elmuez A. Dawi, Foroozan Samimi, Ghusoon Faidhi Hameed, Zahraa Ahmed Taha, Masoud Salavati-Niasari. Green sol-gel auto-combustion synthesis of CeO2/MnCr2O4 nanocomposite using banana juice and its potential application for enhanced degradation of methyl orange under visible light. Alexandria Engineering Journal 2024, 102 , 26-35. https://doi.org/10.1016/j.aej.2024.05.109
Ibrahim F. Waheed, Maha M. Awsaj, Omar S. Dahham, Mustafa Qutaiba Jabbar, Faiz M. Al‑Abady, Mohammed Abbas Fadhil Al-Samarrai. Synthesis of CoMnFe2O4 hollow microstructure decorated GO for photocatalytic degradation of organic dyes. Arabian Journal of Chemistry 2024, 17 (9) , 105934. https://doi.org/10.1016/j.arabjc.2024.105934
Bella Safitri, Heni Yohandini, Muharni Muharni, Salni Salni, Poedji Loekitowati Hariani. Synthesis of NiFe₂O₄ Magnetic Using Artocarpus altilis Leave Extract for Photocatalytic Degradation of Methylene Blue Dye and Antibacterial Applications. Jurnal Kimia Sains dan Aplikasi 2024, 27 (8) , 371-380. https://doi.org/10.14710/jksa.27.8.371-380
Mega Mustikaningrum, Dina Adelina, Fikrah Dian Indrawati Sawali, Moh Azhar Afandy. Effect of Sodium Hydroxide Treatment on Adsorption of Methylene Blue Based on Cellulose Nano Crystals. Journal of Vocational Studies on Applied Research 2024, 6 (1) , 7-11. https://doi.org/10.14710/jvsar.v6i1.22505
Fahma Riyanti, Poedji Loekitowati Hariani, Hasanudin Hasanudin, Addy Rachmat, Widia Purwaningrum. Optimization Photodegradation of Methylene Blue Dye using Bentonite/PDA/Fe3O4@CuO Composite by Response Surface Methodology. Bulletin of Chemical Reaction Engineering & Catalysis 2024, 19 (2) , 252-264. https://doi.org/10.9767/bcrec.20132
Fathima Khyrun Muhammad, Jegatha Christy Arulanandam. Exploring the photocatalytic efficacy of core–shell CeO 2 /TiO 2 nanocomposite synthesized via solution combustion synthesis. Zeitschrift für Physikalische Chemie 2024, https://doi.org/10.1515/zpch-2024-0780
Safanah Sahib Jaafar, Rana Ismael Faeq, Amel Muhson Naji, Olfat A. Nief, Mustafa K. A. Mohammed. Addition of silver nanoparticles to the zinc ferrite/polyaniline composition for boosting its visible photocatalytic degradation. RSC Advances 2024, 14 (36) , 26066-26076. https://doi.org/10.1039/D4RA05096G
Jannatul Mim, Mst. Sabiha Sultana, Palash Kumar Dhar, Md. Kamrul Hasan, Sagar Kumar Dutta. Green mediated synthesis of cerium oxide nanoparticles by using Oroxylum indicum for evaluation of catalytic and biomedical activity. RSC Advances 2024, 14 (35) , 25409-25424. https://doi.org/10.1039/D4RA04132A
Thi Thanh Thuy Mai, Thi Van Anh Nguyen, Thi Binh Phan. Effect of anode passivation on ferrate(VI) electro-generation using ductile iron anode and application for methylene blue treatment. Journal of Applied Electrochemistry 2024, 54 (8) , 1783-1794. https://doi.org/10.1007/s10800-024-02066-3
V. Harshitha, K. S. Manjunatha Kumar, P. C. Nethravathi, D. H. Nagaraju, D. Suresh. Multifunctional Pr-V2O5/rGO hybrid nanomaterial for sensitive heavy metal ion detection and efficient photocatalytic dye degradation. Ionics 2024, 30 (8) , 4853-4870. https://doi.org/10.1007/s11581-024-05571-9
Elham Molahosseini, Hakimeh Zare, Mehdi Molaei, Farzad Farahmandzadeh. Ultrafast degradation of methylene blue from aqueous media by Fe3O4/rGO/SiO2 magnetic nanocomposite in dark catalyst process. Diamond and Related Materials 2024, 147 , 111338. https://doi.org/10.1016/j.diamond.2024.111338
Xiaohui Ji, Chen Li, Junhai Liu, Xuegang Luo. Dual S‐Scheme Ta 3 N 5 /Bi 2 O 2 CO 3 /Ta 2 O 5 With Hierarchical Pore Structures for Enhanced Photodegradation of Dye‐Performance and Mechanism. ChemistrySelect 2024, 9 (26) https://doi.org/10.1002/slct.202400905
Palani Karthik, Jegathalaprathaban Rajesh, Siranjeevi Ravichandran. Enhancement photocatalytic activity of CeO2 infused CA@Gelatin nanocomposites for the degradation of organic dyes under UV-light irradiation. Surfaces and Interfaces 2024, 50 , 104474. https://doi.org/10.1016/j.surfin.2024.104474
Afaq Ullah Khan, Kamran Tahir, Muhammad Zia Ullah Shah, Hissah Saedoon Albaqawi, Zainab M. Almarhoon, Abdulaziz A. Alanazi, Nora Awad Alkudaisi, Talal M. Althagafi, Nacer Badi, Magdi E. A. Zaki. The Hydrothermal-Assisted Approach Improves the Photocatalytic and Energy Storage Performance of Novel CuSe-TiO2-GO Composite. Nanomaterials 2024, 14 (13) , 1136. https://doi.org/10.3390/nano14131136
Kithmini Ranathunga, Piumika Yapa, Imalka Munaweera, M. M. Weerasekera, Chanaka Sandaruwan. Preparation and characterization of Fe–ZnO cellulose-based nanofiber mats with self-sterilizing photocatalytic activity to enhance antibacterial applications under visible light. RSC Advances 2024, 14 (26) , 18536-18552. https://doi.org/10.1039/D4RA03136A
Manisha Mhalsekar, Vrinda Borker. Synthesis of cerium-doped zinc oxide nanomaterials by precursor method with improved photodegradation activity for Methylene blue and Red CL-5B dye. Journal of Materials Science: Materials in Electronics 2024, 35 (16) https://doi.org/10.1007/s10854-024-12776-1
Thanaphon Kansaard, Maneerat Songpanit, Russameeruk Noonuruk, Chakkaphan Wattanawikkam, Wanichaya Mekprasart, Kanokthip Boonyarattanakalin, Chalicheemalapalli Kulala Jayasankar, Wisanu Pecharapa. Er-Doped BiVO4/BiFeO3 Nanocomposites Synthesized via Sonochemical Process and Their Piezo-Photocatalytic Application. Nanomaterials 2024, 14 (11) , 954. https://doi.org/10.3390/nano14110954
Fatima Allawi, M.A. Mahdi, Marwah J. Kadhim, Adel H. Omran Alkhayatt. Preparation and characterization of ZnO/CuO nanocomposites thin films for highly efficient visible-light photocatalysis of acriflavine dye. Optik 2024, 303 , 171722. https://doi.org/10.1016/j.ijleo.2024.171722
Amal A. Atran, Fatma A. Ibrahim, Mohamed S. Hamdy. Functionalization and applications of the versatile CeO2 nanoparticles: A review. Inorganic Chemistry Communications 2024, 163 , 112359. https://doi.org/10.1016/j.inoche.2024.112359
Yuwadee Leelert, Warangluck Na sorn, Thammasak Rojviroon, Sanya Sirivithayapakorn, Ranjith Rajendran, Rattana Muangmora, Nicharee Akechatree, Sutthida Wongwichian, Paramasivam Shanmugam, Chinnasamy Ragavendrand, Phoutthideth Phouheuaghong, Orawan Rojviroon. Synergistic effects of micronanobubbles and AC/Ag–TiO2 nanocomposites in photocatalytic process. Biocatalysis and Agricultural Biotechnology 2024, 57 , 103096. https://doi.org/10.1016/j.bcab.2024.103096
Zahraa A. Abo-Ayad, Modather F. Hussein, Mohamed A. Zayed, Omnia H. Abdelraheem. GC–MS identification of DR31 textile dye degradation products during its efficient electrochemical removal from wastewater media. Journal of Molecular Liquids 2024, 400 , 124408. https://doi.org/10.1016/j.molliq.2024.124408
Ome Parkash Kumar, Muhammad Altaf Nazir, Syed Shoaib Ahmad Shah, Abeer Hashem, Ajay Kumar, Elsayed Fathi Abd_Allah, Aziz ur Rehman. Ternary metal conjugated ZIF-67 coordination with Ag and Ce for the efficient Fenton-like remediation of dyes under visible light. Optical Materials 2024, 150 , 115228. https://doi.org/10.1016/j.optmat.2024.115228
Kathalingam Adaikalam, Dhanasekaran Vikraman, Du-Hee Lee, Yoon-A Cho, Hyun-Seok Kim. Optical and UV Shielding Properties of Inorganic Nanoparticles Embedded in Polymethyl Methacrylate Nanocomposite Freestanding Films. Polymers 2024, 16 (8) , 1048. https://doi.org/10.3390/polym16081048
Sk Mehebub Rahaman, Nargis Khatun, Prashanta Pal, Trishna Mandal, Arnab Patra, Mahasweta Nandi, Bidyut Saha. A deeper insight into the evaluation of water-in-oil amicroemulsion templated samarium sulfide nanospheres: exploring its role in pickering emulsion formulation for photocatalytic dye degradation and synthesis of PANI@Sm 2 S 3 nanocomposites. Nanoscale Advances 2024, 6 (6) , 1688-1703. https://doi.org/10.1039/D3NA01067H
Rahul Ranjan, Smruti B. Bhatt, Rohit Rai, Sanju Kumari Sharma, Muskan Verma, Prodyut Dhar. Valorization of sugarcane bagasse with in situ grown MoS2 for continuous pollutant remediation and microbial decontamination. Environmental Science and Pollution Research 2024, 31 (11) , 17494-17510. https://doi.org/10.1007/s11356-024-32332-y
Mohamed H. H. Ali, Mohamad S. Abdelkarim, Afify D. G. Al-Afify. Characterization and photodegradation of methylene blue dye using bio-synthesized cerium oxide nanoparticles with Spirulina platensis extract. Discover Applied Sciences 2024, 6 (3) https://doi.org/10.1007/s42452-024-05736-1
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Syed Ali Behroz Gilani, Faheem Naseeb, Asma Kiran, Muhammad Umar Ihsan, Javed Iqbal, Hafiz Muhammad Asif Javed, Haq Nawaz Bhatti, Abdulnasser M. Karami, Shahid Hussain, Muhammad ShabirMahr. pH dependent synthesis of ceria nanoparticles for efficient sunlight-driven photocatalysis of methyl orange containing wastewater. Optical Materials 2024, 148 , 114871. https://doi.org/10.1016/j.optmat.2024.114871
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Ketan Maru, Sarita Kalla, Arup K. Ghosh, Ritambhara Jangir. Synthesis of microcrystalline indium (III)-MOF and adsorptive and selective removal of dyes. Research on Chemical Intermediates 2024, 50 (1) , 147-174. https://doi.org/10.1007/s11164-023-05161-w
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Abstract
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Figure 1
Figure 1. Synthesis diagram of the CeO₂-NPs/GO/PAM hydrogel.
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Figure 2
Figure 2. FTIR spectra of the CeO₂-NPs/GO/PAM hydrogel (a) before and (b) after photocatalysis of MB dye.
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Figure 3
Figure 3. XRD patterns of the CeO₂-NPs/GO/PAM hydrogels (a) before and (b) after photocatalysis of MB dye.
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Figure 4
Figure 4. SEM micrographs of the CeO₂-NPs/GO/PAM hydrogel (a) before and (b) after photocatalysis of MB dye.
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Figure 5
Figure 5. EDX spectra of the CeO₂-NPs/GO/PAM hydrogel. The inset table shows the EDX quantification.
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Figure 6
Figure 6. UV–vis spectra of the (a)PAM, (b)GO, (c)GO/PAM, (d)CeO₂-NPs, and (e)CeO₂-NPs/GO/PAM hydrogel solutions.
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Figure 7
Figure 7. (a) Tauc plots of the hydrogel solutions. Extrapolations of the linear portions of the curves for (b) GO/PAM and (c) CeO₂-NPs/GO/PAM.
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Figure 8
Figure 8. Band gap energy estimation of PAM, GO/PAM, and CeO₂-NPs/GO/PAM hydrogels.
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Figure 9
Figure 9. Effect of the amount of (a) CeO₂-NPs and (b) GO in the PAM hydrogel on the photocatalytic degradation of MB dye.
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Figure 10
Figure 10. Effect of (a) pH and (b) initial concentration of MB solution.
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Figure 11
Figure 11. Effect of the type of light irradiation on MB dye degradation.
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Figure 12
Figure 12. Photocatalytic degradation of MB dye under different scavengers.
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Figure 13
Figure 13. Band gap diagram of GO/PAM and CeO₂-NPs/GO/PAM constructed from UV–vis spectroscopy and Tauc plots.
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Figure 14
Figure 14. Langmuir–Hinshelwood plot for photodegradation of MB with CeO₂-NPs/GO/PAM.
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Figure 15
Figure 15. Reusability of the CeO₂-NPs/GO/PAM hydrogel.
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References
This article references 46 other publications.
1. 1
  Owa, F. W. Water pollution: sources, effects, control and management. Int. Lett. Nat. Sci. 2014, 8, 1– 6, DOI: 10.56431/p-gk4d9j
  There is no corresponding record for this reference.
2. 2
  Liu, Q. Pollution and treatment of dye waste-water. IOP Conf. Ser.: Earth Environ. Sci. 2020, 514, 514, DOI: 10.1088/1755-1315/514/5/052001
  There is no corresponding record for this reference.
3. 3
  Wani, K. A.; Jangid, N. K.; Bhat, A. R. Impact of Textile Dyes on Public Health and the Environment in Advances in Human Services and Public Health, IGI Global, 2019.
  There is no corresponding record for this reference.
4. 4
  Azimi, S. C.; Shirini, F.; Pendashteh, A. R. Advanced oxidation process as a green technology for dyes removal from wastewater: A review. Iran. J. Chem. Chem. Eng. 2021, 40, 1467– 1489, DOI: 10.30492/IJCCE.2020.43234
  4
  Advanced oxidation process as a green technology for dyes removal from wastewater: a review
  Azimi, Seyyedeh Cobra; Shirini, Farhad; Pendashteh, Ali Reza
  Iranian Journal of Chemistry & Chemical Engineering (2021), 40 (5), 1467-1489CODEN: IJCEE9; ISSN:1021-9986. (Iranian Research and Development Center for Chemical Industries)
  A review. The combination of green chem. and green engineering is needed for the prodn. of min. waste, renewable sources, increasing utilization of raw materials, the use of simpler and safer products, and novel technologies. The use of novel cleaner technologies leads to effective prodn. in chem. industries. The dyes involve a complex structure, recalcitrant nature, and more intermediates. The generation of oxidative species with higher yields is obtained by advanced oxidn. processes as a green and powerful treatment technol. These processes are effective, inexpensive, and eco-friendly methods for decaying toxic pollutants. The AOPs are classified as non-photochem. and photochem. processes. There are included various technologies such as ozonation, Fenton oxidn., wet air oxidn., electrochem. oxidn., and photocatalytic oxidn. The prodn. of highly reactive free radicals is the main purpose of the AOPs process. The generation of free radical increases by the combination of two or more AOPs processes that leads to higher oxidn. rates. This study was aimed to present the various attempts for degrdn. dyes in textile wastewater using the diverse advanced oxidn. processes.
5. 5
  Karadeniz, D.; Kahya, N.; Erim, F. B. Effective photocatalytic degradation of malachite green dye by Fe (III)-Cross-linked Alginate-Carboxymethyl cellulose composites. J. Photochem. Photobiol. 2022, 428, 113867 DOI: 10.1016/j.jphotochem.2022.113867
  5
  Effective photocatalytic degradation of malachite green dye by Fe(III)-cross-linked alginate-carboxymethyl cellulose composites
  Karadeniz, Duygu; Kahya, Nilay; Erim, F. Bedia
  Journal of Photochemistry and Photobiology, A: Chemistry (2022), 428 (), 113867CODEN: JPPCEJ; ISSN:1010-6030. (Elsevier B.V.)
  Fe(III) ion cross-linked alginate-CM-cellulose composite beads (Fe@(Alg-CMC)) were prepd. and used as a novel photocatalyst for the degrdn. of malachite green (MG) dye. Fe (III) ions bound to the carboxyl groups of the biopolymer composite provided reactive radicals under UV light, and degrdn. of the dye in an aq. soln. occurred at a high percentage and in a short time. Unlike Fenton's reaction, effective degrdn. of the dye was carried out without adding H2O2 to the medium. Optimum conditions of dye degrdn. were investigated. Under UV-A light, 98.8%±0.7% dye degrdn. was achieved at pH 4 of 10 ppm MG soln. with 0.1 g of Fe@(Alg-CMC) beads in 30 min. Exptl. results fitted Langmuir-Hinshelwood kinetic modeling, which explains the kinetics of the heterogeneous catalytic processes. A rate const. (k) of 0.115 ± 0.001 min-1 and correlation coeff. (R2) of 0.9628 was obtained. Hereby, we offer Fe@(Alg-CMC) beads as a promising, environmentally friendly, easy to prep., and low-cost catalyst for the degrdn. of dyes and org. substances under UV light.
6. 6
  Ameta, R.; Benjamin, S.; Ameta, A.; Ameta, S. C. Photocatalytic degradation of organic pollutants: A review. Mater. Sci. Forum. 2013, 734, 247– 272, DOI: 10.4028/www.scientific.net/MSF.734.247
  6
  Photocatalytic degradation of organic pollutants: a review
  Ameta, Rakshit; Benjamin, Surbhi; Ameta, Aarti; Ameta, Suresh C.
  Materials Science Forum (2013), 734 (Photocatalytic Materials & Surfaces for Environmental Cleanup II), 247-272, 27 pp.CODEN: MSFOEP; ISSN:1662-9752. (Trans Tech Publications Ltd.)
  A review. Water pollution is increasing at an ever increasing pace and the whole world is in the cancerous grip of this pollution. Various industries are discharging their untreated effluents into the nearby water resources; thus, adding to the existing water pollution to a great extent. Hence, there is a pressing demand to develop an alternate technol. for wastewater treatment and in this context; photocatalysis has emerged as an Advanced Oxidn. Process with green chem. approach for such a treatment. This chapter deals with photocatalytic degrdn. of different kinds of org. pollutants; mainly surfactants, pesticides, dyes, phenols, chloro compds., nitrogen contg. compds. etc. Mechanisms of their degrdn. have also been discussed with hydroxyl and allied radicals as the main active oxidizing species.
7. 7
  Godiya, C. B.; Xiao, Y.; Lu, X. Amine functionalized sodium alginate hydrogel for efficient and rapid removal of methyl blue in water. Int. J. Biol. Macromol. 2020, 144, 671– 681, DOI: 10.1016/j.ijbiomac.2019.12.139
  7
  Amine functionalized sodium alginate hydrogel for efficient and rapid removal of methyl blue in water
  Godiya, Chirag B.; Xiao, Yonghou; Lu, Xiaolin
  International Journal of Biological Macromolecules (2020), 144 (), 671-681CODEN: IJBMDR; ISSN:0141-8130. (Elsevier B.V.)
  Herein, a potential hydrogel based on sodium alginate (SA) integrated with polyethyleneimine (PEI) was fabricated and employed for the elimination of methyl blue (MB) in aq. media. The SA/PEI hydrogel demonstrated excellent removal performance for MB, i.e. ~ 99% of MB could be removed from water within ~ 30 min using 0.5 g/L SA/PEI hydrogel at 100 mg/L initial concn. The SA/PEI hydrogel presented max. adsorption capacity for MB as-high as 400.0 mg/g with the adsorption isotherm and kinetics abide with the Langmuir isotherm model and pseudo second-order kinetics, resp. The adsorption process followed through chelation between the functionality of the hydrogel and MB as-confirmed by the XPS anal. After four consecutive adsorption/desorption cycles, the adsorption capacity of the SA/PEI hydrogel remained up to ~ 60% of its adsorption capacity in first cycle. Thus, being a cost-effective and eco-friendly material, the SA/PEI hydrogel can be a potential adsorbent in the decontamination of MB in wastewater.
8. 8
  Lapwanit, S.; Sooksimuang, T.; Trakulsujaritchok, T. Adsorptive removal of cationic methylene blue dye by kappacarrageenan/poly(glycidyl methacrylate) hydrogel beads: Preparation and characterization. J. Environ. Chem. Eng. 2018, 6, 6221– 6230, DOI: 10.1016/j.jece.2018.09.050
  8
  Adsorptive removal of cationic methylene blue dye by kappa-carrageenan/poly(glycidyl methacrylate) hydrogel beads: Preparation and characterization
  Lapwanit, Songwut; Sooksimuang, Thanasat; Trakulsujaritchok, Thanida
  Journal of Environmental Chemical Engineering (2018), 6 (5), 6221-6230CODEN: JECEBG; ISSN:2213-3437. (Elsevier Ltd.)
  Kappa-carrageenan hydrogel contg. numerous functional groups used as an environmental-friendly adsorbent shows limitations due to its high water soly., low gel strength and low regeneration ability. In this work, a new biopolymeric-based hydrogel of κ-carrageenan/poly(glycidyl methacrylate) (CG/PG) was prepd. for adsorptive removal of cationic methylene blue (MB) as a toxic dye model. The physicochem. properties and morphol. of the hydrogel beads were characterized by swelling test, FT-IR, TGA and SEM. Parameters affecting the adsorption of MB from aq. soln. such as CG/PG ratios, initial dye concn., soln. pH, time, adsorbent dosage and soln. temp. were investigated in a batch system. Incorporation of PG with reactive function groups into the CG matrix was proven to enhance the adsorption capacity and stability of the hydrogel required for the application of adsorbent as compared to the pristine CG biopolymer. The exptl. adsorption followed pseudo-second order model and well fitted with Langmuir isotherm, with max. MB adsorption of 166.62 mg g-1. Thermodn. parameters indicated that the process was spontaneous and exothermic. The beads could be easily regenerated after washing with ethanol and reused for at least five adsorption-desorption cycles with high efficiency. The fabrication of CG/PG hydrogel beads provided a feasible strategy for the design and modification of bio-based polymers in the field of wastewater treatment.
9. 9
  Hu, T.; Liu, Q.; Gao, T.; Dong, K.; Wei, G.; Yao, J. Facile preparation of tannic acid–poly(vinyl alcohol)/sodium alginate hydrogel beads for methylene blue removal from simulated solution. ACS Omega 2018, 3, 7523– 7531, DOI: 10.1021/acsomega.8b00577
  9
  Facile Preparation of Tannic Acid-Poly(vinyl alcohol)/Sodium Alginate Hydrogel Beads for Methylene Blue Removal from Simulated Solution
  Hu, Tao; Liu, Qinze; Gao, Tingting; Dong, Kaijie; Wei, Gang; Yao, Jinshui
  ACS Omega (2018), 3 (7), 7523-7531CODEN: ACSODF; ISSN:2470-1343. (American Chemical Society)
  A novel hydrogel bead [tannic acid (TA)-poly(vinyl alc.) (PVA)/sodium alginate (SA)] with high strength prepd. by biocompatible PVA, TA, and biocompatible SA via an instantaneous gelation method was applied to remove methylene blue (MB) from aq. soln. The obtained TA-PVA/SA hydrogel beads were fully characterized by thermogravimetric anal., Fourier-transform IR spectroscopy, XPS, SEM, and so on. The adsorption performances of TA-PVA/SA hydrogel beads for MB were investigated by changing the factors of TA content, initial concn., pH, adsorbent dosage, contact time, and temp. systematically. The max. capacity of TA-PVA/SA hydrogel beads for MB removal was obtained to be 147.06 mg/g at 30 °C, whose capability was better than that without TA. After fitting the adsorbed data, it was basically consistent with the Langmuir isotherm and pseudo-second-order kinetic model. Thermodn. studies indicated that MB removal was spontaneous and exothermic in nature. It is concluded that the low-cost TA-PVA/SA hydrogel beads as an easily recoverable adsorbent have a great potential on the removal of hazardous dyes from wastewater.
10. 10
  Malatji, N.; Makhado, E.; Modibane, K. D.; Ramohlola, K. E.; Maponya, T. C.; Monama, G. R.; Hato, M. J. Removal of methylene blue from wastewater using hydrogel nanocomposites: A review. Nanomater. Nanotechnol. 2021, 11, 1– 27, DOI: 10.1177/18479804211039425
  There is no corresponding record for this reference.
11. 11
  Pereira, A. G. B.; Rodrigues, F. H. A.; Paulino, A. T.; Martins, A. F.; Fajardo, A. R. Recent advances on composite hydrogels designed for the remediation of dye-contaminated water and wastewater: A review. J. Cleaner Prod. 2021, 284, 124703 DOI: 10.1016/j.jclepro.2020.124703
  11
  Recent advances on composite hydrogels designed for the remediation of dye-contaminated water and wastewater: A review
  Pereira, Antonio G. B.; Rodrigues, Francisco H. A.; Paulino, Alexandre T.; Martins, Alessandro F.; Fajardo, Andre R.
  Journal of Cleaner Production (2021), 284 (), 124703CODEN: JCROE8; ISSN:0959-6526. (Elsevier Ltd.)
  A review. Dye-contamination in water supplies, industrial effluents, and rivers is one of the major water pollution issues. It has put at risk the drinking-water supplies around the globe. Various remediation approaches have been extensively developed and tested to minimize this worrying scenery. In particular, adsorption techniques are often ranked as one of the most prominent strategies to treat dye-contaminated water likely due to their attractive practical and economic advantages. Overall, the efficiency of adsorptive removal of dyes from water is closely related to the adsorbent material features, which has a crit. role in this process. Currently, thousands of materials (raw or processed) have been tested as adsorbents. Otherwise, none of them have achieved the prominent status assigned to the hydrogels. Frequently labeled as an ideal adsorbent, the leading role of these soft materials towards the adsorptive removal of dyes from the water was consolidated almost two decades ago, when the introduction of different materials into the hydrogel matrixes resulted in composite materials with unique properties. In this paper, an entirely conceptual and crit. review of literature is presented, focusing on the tremendous potential of composite hydrogels to remediate dye-contaminated water. Specifically, the main advances related to the use of composite hydrogels contg. clay minerals, carbonaceous materials, org. fibrils and whiskers, magnetic and metallic particles, and other inorg. fillers are reviewed in this paper. Addnl., general methods to prep. composite hydrogels, the main effects ascribed to the composite formation are addressed in this paper. Finally, the main drawbacks and challenges assocd. with the application of these types of hydrogels are reviewed to understand the research gap and limitations regarding their practical use. We believe that the information provided in this review paper may contribute to enhance the scientific basis for the practical and efficient use of these fascinating adsorbent materials.
12. 12
  Kahya, N.; Erim, F. B. Graphene oxide/chitosan-based composite materials as adsorbents in dye removal. Chem Eng Commun. 2022, 209, 1711– 1726, DOI: 10.1080/00986445.2021.1986700
  12
  Graphene oxide/chitosan-based composite materials as adsorbents in dye removal
  Kahya, Nilay; Erim, F. Bedia
  Chemical Engineering Communications (2022), 209 (12), 1711-1726CODEN: CEGCAK; ISSN:0098-6445. (Taylor & Francis, Inc.)
  A review. Chitosan (Chit) is among the most widely used polysaccharides. Another material that draws attention with its unique phys. and chem. properties is graphene oxide (GO). Reactive groups in the structure of both chitosan and graphene oxide make both materials ideal adsorbents. GO is an excellent adsorbent candidate with its large surface area and mech. strength. However, the difficulty in recovering GO particles as an adsorbent creates a secondary environmental problem. Chitosan shows a weak interest in pos. charged pollutants. The incorporation of GO into chitosan increases both the mech. strength and adsorption capacity of the chitosan. The GO/Chitosan composite also offers the advantage of attracting both pos. and neg. charged pollutants. Over the past five years, an increasing no. of articles have been published reporting the use of GO/Chitosan-based composite materials as adsorbents in dye removal. The adsorption properties of GO/Chitosan-based composites appear to change with the inclusion of materials like magnetite, nano-metal, and other polysaccharides. It is seen that the differences in the prepn. steps of composites of the same structure also affect their adsorption capacities. This paper aims to compile the works between Jan. 2016 and Dec. 2020 on GO/Chitosan-based composites, which were reported to remove dyes from wastewater.
13. 13
  Wang, W.; Wang, Y.; Zhao, Y.; Bai, H.; Huang, M.; Zhang, T.; Song, S. High-performance two-dimensional montmorillonite supported poly(acrylamide-co-acrylic acid) hydrogel for dye removal. Environ. Pollut. 2020, 257, 113574 DOI: 10.1016/j.envpol.2019.113574
  13
  High-performance two-dimensional montmorillonite supported-poly(acrylamide-co-acrylic acid) hydrogel for dye removal
  Wang, Wei; Wang, Jinggang; Zhao, Yunliang; Bai, Haoyu; Huang, Muyang; Zhang, Tingting; Song, Shaoxian
  Environmental Pollution (Oxford, United Kingdom) (2020), 257 (), 113574CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
  High-performance two-dimensional montmorillonite supported-poly (acrylamide-co-acrylic acid) hydrogel for dye removal was investigated. Montmorillonite cooperated with acrylamide and acrylic acid via polymn., hydrogen-bond, amidation and electrostatic interactions to form the three-dimensional reticular-structured hydrogel with the free entrance for macromols. Adsorption tests revealed that the efficient removal (97%) for methylene blue at high concn. (200 mg/L) could be achieved via a small dose of hydrogel (0.5 g/L) within a short time (20 min). The excellent adsorption performance was profited from the electroneg. surface and fully exposed reaction sites of two-dimensional montmorillonite, which could save the treatment cost and promote the removal effect compared with the conventional adsorbents. The adsorption process of methylene blue onto hydrogel could be fitted by both the pseudo-first-order and pseudo-second-order kinetics models, and the adsorption isotherm corresponded to the Sips model. The mechanism anal. based on Fourier transform IR spectroscopy and XPS measurements illustrated that the reaction between carboxyl groups and methylene blue mols. as well as the cation-exchange enabled the hydrogel performing extraordinary adsorption efficiency.
14. 14
  Balkız, G.; Pingo, E.; Kahya, N.; Kaygusuz, H.; Erim, F. B. Graphene oxide/alginate quasi-cryogels for removal of methylene blue. Water Air Soil Pollut. 2018, 229, 131, DOI: 10.1007/s11270-018-3790-5
  There is no corresponding record for this reference.
15. 15
  Dai, H.; Huang, Y.; Huang, H. Eco-friendly polyvinyl alcohol/carboxymethyl cellulose hydrogels reinforced with graphene oxide and bentonite for enhanced adsorption of methylene blue. Carbohydr. Polym. 2018, 185, 1– 11, DOI: 10.1016/j.carbpol.2017.12.073
  15
  Eco-friendly polyvinyl alcohol/carboxymethyl cellulose hydrogels reinforced with graphene oxide and bentonite for enhanced adsorption of methylene blue
  Dai, Hongjie; Huang, Yue; Huang, Huihua
  Carbohydrate Polymers (2018), 185 (), 1-11CODEN: CAPOD8; ISSN:0144-8617. (Elsevier Ltd.)
  Eco-friendly polyvinyl alc./CM-cellulose (isolated from pineapple peel) hydrogels reinforced with graphene oxide and bentonite were prepd. as efficient adsorbents for methylene blue (MB). The structure and morphol. of the prepd. hydrogels were characterized by Fourier transform IR spectroscopy (FTIR), scanning electron microscope (SEM), X-ray diffraction (XRD), thermogravimetry (TG) and differential scanning calorimetry (DSC). Introducing graphene oxide and bentonite into the hydrogels evidently enhanced the thermal stability, swelling ability and MB adsorption capacity. The effects of initial concn. of MB, pH, contact time and temp. on MB adsorption capacity of the prepd. hydrogels were investigated. Adsorption kinetics and equil. adsorption isotherm fitted pseudo-second-order kinetic model and Langmuir isotherm model well, resp. After introducing graphene oxide and bentonite into the hydrogels, the max. adsorption capacity calcd. from the Langmuir isotherm model reached 172.14 mg/g at 30 °C, obviously higher than the hydrogels prepd. without these addns. (83.33 mg/g). Furthermore, all the prepd. hydrogels also displayed good reusability for the efficient removal of MB. Consequently, the prepd. hydrogels could be served as eco-friendly, stable, efficient and reusable adsorbents for anionic dyes in wastewater treatment.
16. 16
  Uyar, G.; Kaygusuz, H.; Erim, F. B. Methylene blue removal by alginate-clay quasi-cryogel beads. React. Funct. Polym. 2016, 106, 1– 7, DOI: 10.1016/j.reactfunctpolym.2016.07.001
  16
  Methylene blue removal by alginate-clay quasi-cryogel beads
  Uyar, Guler; Kaygusuz, Hakan; Erim, F. Bedia
  Reactive & Functional Polymers (2016), 106 (), 1-7CODEN: RFPOF6; ISSN:1381-5148. (Elsevier Ltd.)
  Nowadays, dyes constitute a large part of pollutants and have long been used in dyeing, paper and pulp, textiles, plastics, leather, cosmetics, and food industries. Among the conventional dye removal techniques, adsorption is prominent. Research challenges are on developing low-cost, biodegradable and efficient adsorbents. This study investigates polysaccharide-clay composite beads for the removal of methylene blue dye. Alginate-montmorillonite composite beads were prepd. and then a novel cryogelation-like strategy was developed by deep-freezing the alginate beads at - 21°. This process changed the morphol. of beads and improved surface area and adsorption capacity. The results of the batch adsorption expts. were modeled using isothermal, kinetic, and thermodn. models. It is found that the adsorption is favorable and follows phys. mechanism, with an endothermic process up to 40°. The prepd. composite beads are candidates for effective adsorbents for the dye removal.
17. 17
  Heng, L.; Guo, X.; Guo, T.; Wang, B.; Jiang, L. Strengthening of polymer ordered porous materials based on a layered nanocomposite internal structure. Nanoscale 2016, 8, 13507– 13512, DOI: 10.1039/C6NR03011D
  17
  Strengthening of polymer ordered porous materials based on a layered nanocomposite internal structure
  Heng, Liping; Guo, Xieyou; Guo, Tianqi; Wang, Bin; Jiang, Lei
  Nanoscale (2016), 8 (27), 13507-13512CODEN: NANOHL; ISSN:2040-3372. (Royal Society of Chemistry)
  Ordered porous polymeric films attract more and more attention because they have many advantages and broad application prospects in many fields. Because of their large flexibility and poor mech. properties, some of the scope for application is greatly limited. Inspired by the ordered pore structure of the honeycomb and the layered structure of natural nacre, we prepd. an ordered porous polymer film with a layered structure in the pore wall by the solvent evapn.-restriction assisted hard template method. Compared with other samples, this kind of film with the layered structure showed both excellent mech. properties and good stability. This kind of film with high mech. strength, is considered to have wide applications in the areas of sepn., biomedicine, precision instruments, aerospace, environmental protection and so on.
18. 18
  Ikram, M.; Haider, A.; Bibi, S. T.; Ul-Hamid, A.; Haider, J.; Shahzadi, I. Synthesis of Al/starch co-doped in CaO nanoparticles for enhanced catalytic and antimicrobial activities: experimental and DFT approaches. RSC Adv. 2022, 12, 32142– 32155, DOI: 10.1039/D2RA06340A
  18
  Synthesis of Al/starch co-doped in CaO nanoparticles for enhanced catalytic and antimicrobial activities: experimental and DFT approaches
  Ikram, Muhammad; Haider, Ali; Bibi, Syeda Tayaba; Ul-Hamid, Anwar; Haider, Junaid; Shahzadi, Iram; Nabgan, Walid; Moeen, Sawaira; Ali, Salamat; Goumri-Said, Souraya; Kanoun, Mohammed Benali
  RSC Advances (2022), 12 (50), 32142-32155CODEN: RSCACL; ISSN:2046-2069. (Royal Society of Chemistry)
  In this work, aluminum/starch (St)-doped CaO nanoparticles (NPs) were synthesized by a co-pptn. method to degrade harmful dyes in various pH media. Systematic characterization was performed to investigate the influence of Al/St dopants on the compn., crystal structure, functional groups present, optical characteristics, and morphol. of CaO NPs. Further hybrid d. functional analyses corroborated that the band gap energy was reduced as the Al concn. in starch-doped CaO is increased. Optical absorption spectra of the synthesized materials revealed a red shift upon doping, which indicated depletion in the band gap energy of Al/St-doped CaO. PL spectroscopy showed that the intensity of CaO was reduced by the incorporation of Al and St assigned to min. electron-hole pair recombination. Interlayer spacing and morphol. features were detd. by HR-TEM. HRTEM revealed that the control sample has cubic NPs and the incorporation of St showed overlapping around agglomerated NPs. The d-spacing of CaO was little enhanced by the inclusion of dopants. Exptl. outcomes indicated that the addn. of Co-dopants improved the catalytic potential of CaO NPs. Al (4%)/St-doped CaO NPs expressed a significant redn. of methylene blue in a basic environment. The max. bactericidal performance was obsd. as 10.25 mm and 4.95 mm in the inhibition zone against S. aureus and E. coli, resp., after the addn. of Al and St in CaO.
19. 19
  Mustajab, M.; Ikram, M.; Haider, A.; Ul-Hamid, A.; Nabgan, W.; Haider, J. Promising performance of polyvinylpyrrolidone doped bismuth oxyiodide quantum dots for antibacterial and catalytic applications. Appl. Nanosci. 2022, 12, 2621– 2633, DOI: 10.1007/s13204-022-02547-x
  19
  Promising performance of polyvinylpyrrolidone-doped bismuth oxyiodide quantum dots for antibacterial and catalytic applications
  Mustajab, Muhammad; Ikram, Muhammad; Haider, Ali; Ul-Hamid, Anwar; Nabgan, Walid; Haider, Junaid; Ghaffar, Rabia; Shahzadi, Anum; Ghaffar, Abdul; Saeed, Aamer
  Applied Nanoscience (2022), 12 (9), 2621-2633CODEN: ANPACY; ISSN:2190-5517. (Springer GmbH)
  Abstr.: In the present research study, the co-pptn. method was used to obtain novel bismuth oxyiodide quantum dots (BiOI QDs) with incorporation of various concns. (3, 6 and 9%) of polyvinylpyrrolidone (PVP) as a dopant. The no. of characterizations was employed to check the structural, morphol. and optical properties of prepd. samples. The hexagonal structure of BiOI has been confirmed by using x-ray diffraction (XRD) investigation. In addn., with increasing dopant concn. significant decreased in crystallite size was obsd. as 44.5, 19.9, 25.8 and 23.2 nm, while cryst. nature of synthesized QDs was confirmed by bright circular rings patterns of SAED. Micrographs of QDs were obtained using transmission electron microscope (TEM), and interlayer d-spacing was calcd. using HRTEM anal. FTIR spectra have been utilized to establish the existence of functional groups in addn. to recording the vibrational characteristic peak of BiOI. The bandgap energy increased gradually upon doping in the range of 2.86-2.93 eV. The dye degrdn. of toxic methylene blue (MB) has been examd. by applying doped and host BiOI nanocatalyst in the appearance of sodium borohydride (NaBH4). Dye elimination was found increasing with dopant concn. as 9% PVP-doped BiOI explored as a superior catalyst providing high MB degrdn. rate 99.50% in basic medium within seconds. Addnl., the antibacterial activity was tested against staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) pathogens; significant inhibition zone was measured against S. aureus bacteria as 4.60 mm.
20. 20
  Zhao, Y.; Kang, S.; Qin, L.; Wang, W.; Zhang, T.; Song, S.; Komarneni, S. Self-assembled gels of Fe-chitosan/montmorillonite nanosheets: dye degradation by the synergistic effect of adsorption and photo-Fenton reaction. Chem. Eng. J. 2020, 379, 122322 DOI: 10.1016/j.cej.2019.122322
  20
  Self-assembled gels of Fe-chitosan/montmorillonite nanosheets: Dye degradation by the synergistic effect of adsorption and photo-Fenton reaction
  Zhao, Yunliang; Kang, Shichang; Qin, Lei; Wang, Wei; Zhang, Tingting; Song, Shaoxian; Komarneni, Sridhar
  Chemical Engineering Journal (Amsterdam, Netherlands) (2020), 379 (), 122322CODEN: CMEJAJ; ISSN:1385-8947. (Elsevier B.V.)
  Self-assembled gel of Fe-chitosan/montmorillonite nanosheets (Fe-CS/MMTNS) was prepd. for elimination of methylene blue (MB) under visible light in the presence of H2O2. The Fe-CS/MMTNS gel was characterized by FTIR, SEM-EDS, XPS and TG. The Fe-CS/MMTNS gel performed well in the removal of MB through the synergistic effect of adsorption and photo-Fenton reaction. Moreover, this gel worked efficiently under a wide range of pH conditions. This composite gel also showed effective reusability because the adsorption sites of the Fe-CS/MMTNS are continually reactivated through photo-Fenton degrdn. Addnl., the Fe-CS/MMTNS gel was found to be stable and the iron ions were hardly leached out because of the complexation between iron and chitosan (CS). The MB degrdn. occurred by two pathways: a part of MB was directly attacked by reactive radicals and gradually converted into inorg. substances while another part of MB was firstly adsorbed by Fe-CS/MMTNS gel and then degraded by reactive radicals.
21. 21
  Lahive, E.; Jurkschat, K.; Shaw, B. J.; Handy, R. D.; Spurgeon, D. J.; Svendsen, C. Toxicity of cerium oxide nanoparticles to the earthworm Eisenia fetida: subtle effects. Environ. Chem. 2014, 11, 268– 278, DOI: 10.1071/EN14028
  21
  Toxicity of cerium oxide nanoparticles to the earthworm Eisenia fetida: subtle effects
  Lahive, Elma; Jurkschat, Kerstin; Shaw, Benjamin J.; Handy, Richard D.; Spurgeon, David J.; Svendsen, Claus
  Environmental Chemistry (2014), 11 (3), 268-278CODEN: ECNHAA; ISSN:1449-8979. (CSIRO Publishing)
  Environmental context This study investigates the toxicity of cerium oxide nanoparticles to earthworms, key organisms in soil ecosystems. Cerium oxide did not affect survival or reprodn. of the earthworms but did exert histol. changes. We conclude that current soil guidelines, based simply on metal toxicity, appear to adequately protect against cerium exposure risk, at least for earthworms. Abstr. The toxicity of cerium oxide (CeO2) nanoparticles (NPs) in soils is largely unknown. This study aimed to investigate the toxicity of three different CeO2 NPs to the earthworm, Eisenia fetida, for effects on survival (at day 28) and reprodn. (at day 56), as well as bioaccumulation and histopathol. effects. Eisenia fetida were exposed in std. Lufa 2.2 soil to three CeO2 NPs of different size ranges (5-80nm), one larger particle (300nm) and a cerium salt (ammonium cerium nitrate) over an exposure range from 41-10000mgCekg-1. Survival and reprodn. were not affected by the four CeO2 particles, even at the highest exposure concn. tested. Alternatively, 10000mgCekg-1 cerium salt affected survival and reprodn.; Median lethal concn. (LC50) and effective concn. (EC50) values were 317.8 and 294.6mgCekg-1. Despite a lack of toxic effect from the different forms of CeO2 particles, there was a dose-dependent increase in cerium in the organisms at all exposure concns., and for all material types. Earthworms exposed to CeO2 particles had higher concns. of total cerium compared to those exposed to ionic cerium, but without exhibiting the same toxic effect. Histol. observations in earthworms exposed to the particulate forms of CeO2 did, however, show cuticle loss from the body wall and some loss of gut epithelium integrity. The data suggest that that CeO2 NPs do not affect survival or reprodn. in E. fetida over the std. test period. However, there were histol. changes that could indicate possible deleterious effects over longer-term exposures.
22. 22
  Kızılkonca, E.; Torlak, E.; Erim, F. B. Preparation and characterization of antibacterial nano cerium oxide/chitosan/hydroxyethylcellulose/polyethylene glycol composite films. Int. J. Biol. Macromol. 2021, 177, 351– 359, DOI: 10.1016/j.ijbiomac.2021.02.139
  22
  Preparation and characterization of antibacterial nano cerium oxide/chitosan/hydroxyethylcellulose/polyethylene glycol composite films
  Kizilkonca, Ezgi; Torlak, Emrah; Erim, F. Bedia
  International Journal of Biological Macromolecules (2021), 177 (), 351-359CODEN: IJBMDR; ISSN:0141-8130. (Elsevier B.V.)
  Due to the rapidly increasing biol. applications and antibacterial properties of versatile nano cerium oxide particles, the effects of these particles on chitosan-based films were investigated. Chitosan-based composite films with and without cerium oxide nanoparticles (NPs) were prepd. by a casting method. Hydroxyethylcellulose (HEC) was used for the flexibility of films, and polyethylene glycol (PEG) was used as a plasticizer in the blending stage of film prepn. Characterizations of films were done by Fourier transform IR spectroscopy (FTIR), thermogravimetric analyzer (TGA), and dynamic mech. analyzer (DMA). Cerium oxide nanoparticle incorporation enhanced the antibacterial activity of chitosan-based films against Escherichia coli and Staphylococcus aureus. This composite film is proposed as packaging or coating material because of its flexibility, antibacterial efficacy, and good mech. strength.
23. 23
  Kalaycıoğlu, Z.; Kahya, N.; Adımcılar, V.; Kaygusuz, H.; Torlak, E.; Akın-Evingür, G.; Erim, F. B. Antibacterial nano cerium oxide/chitosan/cellulose acetate composite films as potential wound dressing. Eur. Polym. J. 2020, 133, 109777 DOI: 10.1016/j.eurpolymj.2020.109777
  23
  Antibacterial nano cerium oxide/chitosan/cellulose acetate composite films as potential wound dressing
  Kalaycioglu, Zeynep; Kahya, Nilay; Adimcilar, Veselina; Kaygusuz, Hakan; Torlak, Emrah; Akin-Evingur, Gulsen; Erim, F. Bedia
  European Polymer Journal (2020), 133 (), 109777CODEN: EUPJAG; ISSN:0014-3057. (Elsevier Ltd.)
  Novel chitosan and cellulose acetate polymer composites with nanosized cerium oxide were prepd. as potential wound dressing materials. Chitosan and cellulose acetate are natural polymer derivs. with biocompatible properties. Both polymers can be dissolved in formic acid. The polymer composite was formed by solvent-casting method. The formed films were not sol. in water. In order to improve antibacterial, thermal, and mech. properties of the composite material, films were loaded with nanosized cerium oxide. Films were characterized with thermogravimetric, SEM with energy-dispersive X-ray spectroscopy, mech., UV-visible light transmittance, water soly., pH, moisture content, water vapor transmission rate, swelling, and antibacterial tests. The phys. properties and antibacterial characteristics of the films are promising for further research as a potential wound covering material.
24. 24
  Kızılkonca, E.; Erim, F. B. Development of anti-aging and anticorrosive nanoceria dispersed alkyd coating for decorative and industrial purposes. Coatings 2019, 9, 610, DOI: 10.3390/coatings9100610
  24
  Development of anti-aging and anticorrosive nanoceria dispersed alkyd coating for decorative and industrial purposes
  Kizilkonca, Ezgi; Erim, F. Bedia
  Coatings (2019), 9 (10), 610CODEN: COATED; ISSN:2079-6412. (MDPI AG)
  This study focuses on nano cerium oxide particles as alternative additives in solvent-based alkyd coatings in order to improve anticorrosive and anti-aging properties. The paint samples were formulated with cerium oxide micro and nanoparticles, and the coating quality characteristics were compared with coating formulated with com. anticorrosive and UV-aging agents. Formulations were prepd. with 3 wt % com. anticorrosive agent as ref. material (RP), 3 wt % cerium oxide microparticles (CER1), 3 wt % and 1% cerium oxide nanoparticles (CER2 and CER3), resp. The basket milling technique with zirconium balls was used for the prepns. of coatings and characterizations were performed by Fourier transform IR spectroscopy (FTIR), thermogravimetric anal. (TGA), and contact angle measurements. Improvement in the anticorrosive properties was proven with electrochem. impedance spectroscopy (EIS) and accelerated salt spray tests based on ISO 4628 Evaluation of Degrdn. of Coatings. Furthermore, phys. and mech. tests were run according to std. test methods for coatings and reported. Results showed that cerium oxide particles provide anticorrosive, UV defender, and self-cleaning effects, besides excellent phys. resistance to alkyd coatings. The impact of cerium oxide nanoparticles was found to be stronger than those of the microparticles.
25. 25
  Kaygusuz, H.; Erim, F. B. Biopolymer-assisted green synthesis of functional cerium oxide nanoparticles. Chem. Pap. 2020, 74, 2357– 2363, DOI: 10.1007/s11696-020-01084-7
  25
  Biopolymer-assisted green synthesis of functional cerium oxide nanoparticles
  Kaygusuz, Hakan; Erim, F. Bedia
  Chemical Papers (2020), 74 (7), 2357-2363CODEN: CHPAEG; ISSN:1336-9075. (Springer International Publishing AG)
  Cerium oxide nanoparticles were synthesized by thermal decompn. of cerium alginate biopolymer gel at 450° C, where alginate both acts as a precursor and a template. The synthesis is a green, facile and one-step method and the resulting nanoparticles have functionalized surface. The resulted material were characterized using X-ray diffraction for confirmation of cerium oxide, crystallite size anal. and grain size distribution. Transmission electron microscopy was used for the particle size detn., hydrodynamic size estn. was studied by dynamic light scattering and surface characteristics were analyzed using zeta potential measurements. Results show the presence of spherical particles with a size of < 5 nm. Having only a neg. surface charge in such a wide pH range will ensure that the behavior of obtained nanoparticles in different environments is predictable. Isoelec. point of the synthesized material is significantly different from non-functionalized cerium oxide, and indicates the surface functionality, which is an important property for biocompatibility.
26. 26
  Kalaycıoğlu, Z.; Gecim, B.; Erim, F. B. Green synthesis of cerium oxide nanoparticles from turmeric and kinds of honey: Characterizations, antioxidant and photocatalytic dye degradation activities. Adv. Nat. Sci.: Nanosci. Nanotechnol. 2022, 13, 015016 DOI: 10.1088/2043-6262/ac5dc5
  There is no corresponding record for this reference.
27. 27
  Channei, D.; Nakaruk, A.; Phanichphant, S. Influence of graphene oxide on photocatalytic enhancement of cerium dioxide. Mater. Lett. 2017, 209, 43– 47, DOI: 10.1016/j.matlet.2017.07.109
  27
  Influence of graphene oxide on photocatalytic enhancement of cerium dioxide
  Channei, Duangdao; Nakaruk, Auppatham; Phanichphant, Sukon
  Materials Letters (2017), 209 (), 43-47CODEN: MLETDJ; ISSN:0167-577X. (Elsevier B.V.)
  Graphene oxide (GO) was prepd. by oxidizing purified natural flake graphite via modified Hummers method. The suspension of GO particles and cerium-based precursors were treated hydrothermally in order to prep. CeO2/GO composites. The disappearance of the [0 0 1] GO diffraction peak was observable in the XRD pattern for CeO2/GO composites because the crystal growth of CeO2 between the interlayer of GO destroyed the regular layer stacking of GO phase. However XPS spectra of O 1 s core level and oxygen vacancies defect in CeO2 caused the decrease in degree of crystallinity. Composite of CeO2 with GO not only prevented the formation of extrinsic vacancies in the oxygen sub-lattice, but also prevented the switching from the major photoactive species Ce4+ to Ce3+. The photocatalytic activity measurements demonstrated that the CeO2/GO composites exhibited much higher photocatalytic activity than CeO2 for degrdn. of methylene blue (MB) under visible light irradn. The enhancement of photocatalytic activity could be attributed to the excellently elevated absorption ability for the MB dye through π-π conjugation. As reported in PL results, the effective inhibition of the recombination of photogenerated electron-hole pairs due to the charge interaction between CeO2 and GO.
28. 28
  Channei, D.; Chansaenpak, K.; Phanichphant, S.; Jannoey, P.; Khanitchaidecha, W.; Nakaruk, A. Synthesis and characterization of WO₃/CeO₂ heterostructured nanoparticles for photodegradation of indigo carmine dye. ACS Omega 2021, 6, 19771– 19777, DOI: 10.1021/acsomega.1c02453
  28
  Synthesis and Characterization of WO3/CeO2 Heterostructured Nanoparticles for Photodegradation of Indigo Carmine Dye
  Channei, Duangdao; Chansaenpak, Kantapat; Phanichphant, Sukon; Jannoey, Panatda; Khanitchaidecha, Wilawan; Nakaruk, Auppatham
  ACS Omega (2021), 6 (30), 19771-19777CODEN: ACSODF; ISSN:2470-1343. (American Chemical Society)
  WO3/CeO2 heterostructured nanocomposites contg. different WO3 ratios (0.1, 0.3, 0.5, and 1.0%) were synthesized by a pptn. method. The coupling of CeO2 and WO3 with a high sp. surface area noticeably enhanced the photocatalytic activity of indigo carmine (IC) degrdn. under visible-light irradn. The degrdn. rate consts. (k) of 0.5% WO3/CeO2 nanocomposites reached 4 and 5 times higher than those of CeO2 and WO3, resp. Regarding the exptl. results, the XRD patterns of the CeO2 spherical nanoparticles and rod-shaped WO3 were assigned to the cubic fluorite and orthorhombic phase structures, resp. The increasing photocatalytic activity of nanocomposite samples could be attributed to the heterojunction of the photocatalysts with efficient charge sepn. and strong oxidative ability, which were confirmed by the photoluminescence spectra and diffuse reflectance spectrometry. The staggered heterojunction of the nanocomposite promoted efficient electron transfer and suppressed the recombination of photogenerated electrons and holes during the process.
29. 29
  Moradi, B.; Nabiyouni, G.; Ghanbari, D. Rapid photo-degradation of toxic dye pollutants: green synthesis of mono-disperse Fe₃O₄-CeO₂ nanocomposites in the presence of lemon extract. J. Mater. Sci.: Mater. Electron. 2018, 29, 11065– 11080, DOI: 10.1007/s10854-018-9189-7
  29
  Rapid photo-degradation of toxic dye pollutants: green synthesis of mono-disperse Fe3O4-CeO2 nanocomposites in the presence of lemon extract
  Moradi, Banafsheh; Nabiyouni, Gholamreza; Ghanbari, Davood
  Journal of Materials Science: Materials in Electronics (2018), 29 (13), 11065-11080CODEN: JSMEEV; ISSN:0957-4522. (Springer)
  Fe3O4 nanoparticles were first synthesized via a fast pptn. method. CeO2 and Fe3O4-CeO2 nanocomposites then were prepd. using hydrothermal method with a green procedure in the presence of lemon ext. The effect of time, pH and applied magnetic field on the size and shape of nanostructures were investigated. The prepd. products were characterized using X-ray diffraction, SEM, and Fourier transform IR spectroscopy. Vibrating sample magnetometer was used to study the magnetic property of the products. The results illustrated super-paramagnetic behavior of Fe3O4 nanoparticles. The photo-catalytic behavior of Fe3O4-CeO2 nanocomposites was evaluated using the degrdn. of two azo dyes under UV light irradn. The results show that the prepd. nanocomposites have potential application for magnetic and photo-catalytic performance.
30. 30
  Kusmierek, E. A CeO₂ semiconductor as a photocatalytic and photo electrocatalytic material for the remediation of pollutants in industrial wastewater: A review. Catalysts 2020, 10, 1435, DOI: 10.3390/catal10121435
  30
  A CeO2 semiconductor as a photocatalytic and photoelectrocatalytic material for the remediation of pollutants in industrial wastewater: a review
  Kusmierek, Elzbieta
  Catalysts (2020), 10 (12), 1435CODEN: CATACJ; ISSN:2073-4344. (MDPI AG)
  A review. The direct discharge of industrial wastewater into the environment results in serious contamination. Photocatalytic treatment with the application of sunlight and its enhancement by coupling with electrocatalytic degrdn. offers an inexpensive and green technol. enabling the total removal of refractory pollutants such as surfactants, pharmaceuticals, pesticides, textile dyes, and heavy metals, from industrial wastewater. Among metal oxide-semiconductors, cerium dioxide is one of the photocatalysts most commonly applied in pollutant degrdn. CeO2 exhibits promising photocatalytic activity. Nonetheless, the position of conduction bands and valence bands in CeO2 limits its application as an efficient photocatalyst utilizing solar energy. Its photocatalytic activity in wastewater treatment can be improved by various modification techniques, including changes in morphol., doping with metal cation dopants and non-metal dopants, coupling with other semiconductors, and combining it with carbon supporting materials. This paper presents a general overview of CeO2 application as a single or composite photocatalyst in the treatment of various pollutants. The photocatalytic characteristics of CeO2 and its composites are described. The main photocatalytic reactions with the participation of CeO2 under UV and VIS irradn. are presented. This review summarizes the existing knowledge, with a particular focus on the main exptl. conditions employed in the photocatalytic and photoelectrocatalytic degrdn. of various pollutants with the application of CeO2 as a single and composite photocatalyst.
31. 31
  Yadav, S.; Raman, A. P. S.; Meena, H.; Goswami, A. G.; Vinod Kumar, B.; Jain, P. An update on graphene oxide: applications and toxicity. ACS Omega 2022, 7, 35387– 35445, DOI: 10.1021/acsomega.2c03171
  31
  An Update on Graphene Oxide: Applications and Toxicity
  Yadav, Sandeep; Singh Raman, Anirudh Pratap; Meena, Harshvardhan; Goswami, Abhay Giri; Bhawna; Kumar, Vinod; Jain, Pallavi; Kumar, Gyanendra; Sagar, Mansi; Rana, Devendra Kumar; Bahadur, Indra; Singh, Prashant
  ACS Omega (2022), 7 (40), 35387-35445CODEN: ACSODF; ISSN:2470-1343. (American Chemical Society)
  A review. Graphene Oxide (GO) has attracted much attention in past few years because of its interesting and promising elec., thermal, mech., and structural properties. These properties can be altered as GO can be readily functionalized. Brodie synthesized the GO in 1859 by reacting graphite with KClO3 in the presence of fuming HNO3; the reaction took 3-4 days to complete at 333 K. Since then, various schemes have been developed to reduce the reaction time, increase the yield and minimize the release of toxic byproducts (NO2 and N2O4). Modified Hummers method has been widely accepted to produce GO in bulk. Due to its versatile characteristics, GO has wide range of applications in different fields like tissue engineering, photocatalytic, catalysis, and biomedical applications. Its porous structure is considered appropriate for tissue and organ regeneration. Various branches of tissue engineering are being extensively explored, such as bone, neural, dentistry, cartilage and skin tissue engineering. The bandgap of GO can be easily tuned and therefore, it has a wide range of photocatalytic applications as well; degrdn. of org. contaminants, hydrogen generation and CO2 redn. etc. GO could be a potential nanocarrier in drug delivery systems, gene delivery, biol. sensing and antibacterial nanocomposites due to its large surface area and high d., as it is highly functionalized with oxygen contg. functional groups. GO or its composites are found toxic to various biol. species and is also discussed in this review. It has been obsd. that SOD and ROS levels gradually increase over a period after GO is introduced in the biol. systems. Hence, GO at specific concns. is toxic for various species like earthworms, Chironomus riparius, Zebrafish etc.
32. 32
  Channei, D.; Nakaruk, A.; Phanichphant, S. Influence of graphene oxide on photocatalytic enhancement of cerium dioxide. Mater. Lett. 2017, 209, 43– 47, DOI: 10.1016/j.matlet.2017.07.109
  32
  Influence of graphene oxide on photocatalytic enhancement of cerium dioxide
  Channei, Duangdao; Nakaruk, Auppatham; Phanichphant, Sukon
  Materials Letters (2017), 209 (), 43-47CODEN: MLETDJ; ISSN:0167-577X. (Elsevier B.V.)
  Graphene oxide (GO) was prepd. by oxidizing purified natural flake graphite via modified Hummers method. The suspension of GO particles and cerium-based precursors were treated hydrothermally in order to prep. CeO2/GO composites. The disappearance of the [0 0 1] GO diffraction peak was observable in the XRD pattern for CeO2/GO composites because the crystal growth of CeO2 between the interlayer of GO destroyed the regular layer stacking of GO phase. However XPS spectra of O 1 s core level and oxygen vacancies defect in CeO2 caused the decrease in degree of crystallinity. Composite of CeO2 with GO not only prevented the formation of extrinsic vacancies in the oxygen sub-lattice, but also prevented the switching from the major photoactive species Ce4+ to Ce3+. The photocatalytic activity measurements demonstrated that the CeO2/GO composites exhibited much higher photocatalytic activity than CeO2 for degrdn. of methylene blue (MB) under visible light irradn. The enhancement of photocatalytic activity could be attributed to the excellently elevated absorption ability for the MB dye through π-π conjugation. As reported in PL results, the effective inhibition of the recombination of photogenerated electron-hole pairs due to the charge interaction between CeO2 and GO.
33. 33
  Nemati, F.; Rezaie, M.; Tabesh, H.; Eid, K.; Xu, G.; Ganjali, M. R. Cerium functionalized graphene nano-structures and their applications; A review. Environ. Res. 2022, 208, 112685 DOI: 10.1016/j.envres.2022.112685
  33
  Cerium functionalized graphene nano-structures and their applications; A review
  Nemati, Fatemeh; Rezaie, Maryam; Tabesh, Hadi; Eid, Kamel; Xu, Guobao; Ganjali, Mohammad Reza; Hosseini, Morteza; Karaman, Ceren; Erk, Nevin; Show, Pau-Loke; Zare, Najmeh; Karimi-Maleh, Hassan
  Environmental Research (2022), 208 (), 112685CODEN: ENVRAL; ISSN:0013-9351. (Elsevier Inc.)
  A review. Graphene-based nanomaterials with remarkable properties, such as good biocompatibility, strong mech. strength, and outstanding elec. cond., have dramatically shown excellent potential in various applications. Increasing surface area and porosity percentage, improvement of adsorption capacities, redn. of adsorption energy barrier, and also prevention of agglomeration of graphene layers are the main advantages of functionalized graphene nanocomposites. On the other hand, Cerium nanostructures with remarkable properties have received a great deal of attention in a wide range of fields; however, in some cases low cond. limits their application in different applications. Therefore, the combination of cerium structures and graphene networks has been widely invesitaged to improve properties of the composite. In order to have a comprehensive information of these nanonetworks, this research reviews the recent developments in cerium functionalized graphene derivs. (graphene oxide (GO), reduced graphene oxide (RGO), and graphene quantum dot (GQD) and their industrial applications. The applications of functionalized graphene derivs. have also been successfully summarized. This systematic review study of graphene networks decorated with different structure of Cerium have potential to pave the way for scientific research not only in field of material science but also in fluorescent sensing, electrochem. sensing, supercapacitors, and catalyst as a new candidate.
34. 34
  Moztahida, M.; Lee, D. S. Photocatalytic degradation of methylene blue with P25/graphene/polyacrylamide hydrogels: Optimization using response surface methodology. J. Hazard. Mater. 2020, 400, 123314 DOI: 10.1016/j.jhazmat.2020.123314
  34
  Photocatalytic degradation of methylene blue with P25/graphene/polyacrylamide hydrogels: Optimization using response surface methodology
  Moztahida, Mokrema; Lee, Dae Sung
  Journal of Hazardous Materials (2020), 400 (), 123314CODEN: JHMAD9; ISSN:0304-3894. (Elsevier B.V.)
  An environment-friendly hydrogel was synthesized by entrapping Degussa P25 on the surface of a reduced graphene oxide (rGO)-polyacrylamide (PAM) matrix. The PAM content of the P25-rGO-PAM (PGP) hydrogel considerably influenced the adsorption and photocatalytic degrdn. of methylene blue (MB), and the optimal PAM content was 10% (w/v). Furthermore, rGO not only enhanced the adsorption capacity of the hydrogel by increasing the surface area but also increased the photodegrdn. efficiency synergistically by seperating electron-hole pairs. The reaction kinetic const. for MB degrdn. by the hydrogel was 0.0276 min-1, which was three and five times the reaction kinetic consts. of P25-PAM and rGO-PAM hydrogels, resp. The synthesized PGP showed high stability and its MB degrdn. efficiency was considerably high up to five consecutive cycles under UV-irradn. The eco-friendly nature of the hydrogel was evaluated on the basis of bacterial inactivation, and the treated water was found to be safe for use. Three key operating parameters (initial MB concn., temp., and pH) were optimized for maximizing MB removal using a response surface methodol. The complete MB removal efficiency was obtained for the optimal conditions of pH 9.4, a temp. of 31.2°C, and an initial MB concn. of 5.2 mg/L.
35. 35
  Mansurov, R. R.; Safronov, A. P.; Lakiza, N. V.; Beketov, I. V. Photocatalytic activity of titanium dioxide nanoparticles immobilized in the polymer network of polyacrylamide hydrogel. Russ. J. Appl. Chem. 2017, 90, 1712– 1721, DOI: 10.1134/S1070427217100238
  35
  Photocatalytic Activity of Titanium Dioxide Nanoparticles Immobilized in Polymer Network of Polyacrylamide Hydrogel
  Mansurov, R. R.; Safronov, A. P.; Lakiza, N. V.; Beketov, I. V.
  Russian Journal of Applied Chemistry (2017), 90 (10), 1712-1721CODEN: RJACEO; ISSN:1070-4272. (Pleiades Publishing, Ltd.)
  Composite hydrogels based on polyacrylamide immobilized nanoparticles of com. (P25 brand) titanium dioxide and of titanium dioxide nanoparticles prepd. by elec. explosion of a wire were synthesized. The enthalpy of interaction at the polyacrylamide/TiO2 interface was detd. by microcalorimetry using the thermochem. cycle method. Interaction of polyacrylamide polymer chains with the surface of TiO2 nanoparticles is energetically unfavorable. The absence of interactions between the hydrogel polymer network and surface of TiO2 nanoparticles favors manifestation of the UV-induced photocatalytic activity of TiO2 nanoparticles immobilized in the hydrogel. Immobilization in the polyacrylamide hydrogel matrix decreases the photocatalytic activity of P25 brand TiO2 nanoparticles, but does not affect the photocatalytic activity of titanium dioxide nanoparticles prepd. by the elec. explosion method. The photocatalytic activity of TiO2 nanoparticles immobilized in the bulk of polyacrylamide hydrogel evaluated by the decompn. of Methyl orange dye is controlled by the diffusion rate of the dye mols. into the bulk of the hydrogel and depends also on the aggregation of TiO2 nanoparticles in the hydrogel matrix.
36. 36
  Kazemi, F.; Mohamadnia, Z.; Kaboudin, B.; Karimi, Z. Photodegradation of methylene blue with a titanium dioxide/polyacrylamide photocatalyst under sunlight. J. Appl. Polym. Sci. 2016, 133, 43386 DOI: 10.1002/app.43386
  There is no corresponding record for this reference.
37. 37
  Pasikhani, J. V.; Gilani, N.; Pirbazari, A. E. Improvement the wastewater purification by TiO₂ nanotube arrays: The effect of etching-step on the photo-generated charge carriers and photocatalytic activity of anodic TiO₂ nanotubes. Solid State Sci. 2018, 84, 57– 74, DOI: 10.1016/j.solidstatesciences.2018.08.003
  37
  Improvement the wastewater purification by TiO2 nanotube arrays: The effect of etching-step on the photo-generated charge carriers and photocatalytic activity of anodic TiO2 nanotubes
  Pasikhani, Javad Vahabzadeh; Gilani, Neda; Pirbazari, Azadeh Ebrahimian
  Solid State Sciences (2018), 84 (), 57-74CODEN: SSSCFJ; ISSN:1293-2558. (Elsevier Masson SAS)
  The current study demonstrates how the etching step in anodization process effects on the photocatalytic activity of TiO2 nanotubes. In this regard, the TiO2 nanotubes were made by one-step and two-step anodization process on two different substrates Ti and etched-Ti foils, resp. The results revealed that two-step anodization process is a beneficial way to prep. highly well-organized structure and regular surface. The two-step anodization by an enhancement in the fluoride ions diffusion led to a decrease in nanotubes' porosity and an increment in the nanotubes' surface area, a factor of roughness, and the ratio of length to diam., resp. As a consequence of the improvement in geometrical properties, the two-step TiO2 nanotubes led to the intensification of photocurrent d. (from 0.383 to 0.677 mA cm-2) and photoconversion efficiency (from 0.18% to 0.29%) in comparison with the one-step nanotubes, resp. Further, a synergetic impact of the photoelectrochem. measurement and photocatalytic process was obsd. The degrdn. efficiencies of 2,4-dichlorophenol by two-step nanotubes increased from 47 to 55% under visible light, and from 58 to 72% under UV irradn., which it was attributed to more light harvesting, more photo-generated electrons, higher sepn. efficiency and improvement in geometrical properties.
38. 38
  Godwin Uranta, K.; Rezaei-Gomari, S.; Russell, P.; Hamad, F. Studying the effectiveness of polyacrylamide (PAM) application in hydrocarbon reservoirs at different operational conditions. Energies 2018, 11, 2201, DOI: 10.3390/en11092201
  There is no corresponding record for this reference.
39. 39
  Luceño-Sánchez, J. A.; Maties, G.; Gonzalez-Arellano, C.; Díez-Pascual, A. M. Synthesis and characterization of graphene oxide derivatives via functionalization reaction with hexamethylene diisocyanate. 2019, 3, 8. 10.3390/IOCN_2018-1-05485.
  There is no corresponding record for this reference.
40. 40
  Abid; Sehrawat, P.; Islam, S. S.; Mishra, P.; Ahmad, S. Reduced graphene oxide (rGO) based wideband optical sensor and the role of temperature, defect states and quantum efficiency. Sci. Rep. 2018, 8, 3537 DOI: 10.1038/s41598-018-21686-2
  40
  Reduced graphene oxide (rGO) based wideband optical sensor and the role of Temperature, Defect States and Quantum Efficiency
  Abid; Sehrawat Poonam; Islam S S; Mishra Prabhash; Ahmad Shahab
  Scientific reports (2018), 8 (1), 3537 ISSN:.
  We report a facile and cost-effective approach to develop self-standing reduced Graphene Oxide (rGO) film based optical sensor and its low-temperature performance analysis where midgap defect states play a key role in tuning the crucial sensor parameters. Graphite oxide (GO) is produced by modified Hummers' method and reduced thermally at 250 °C for 1 h in Argon atmosphere to obtain rGO. Self-standing rGO film is prepared via vacuum filtration. The developed film is characterized by HRTEM, FESEM, Raman, and XRD techniques. The developed sensor exhibits highest sensitivity towards 635 nm illumination wavelength, irrespective of the operating temperature. For a given excitation wavelength, photoresponse study at low temperature (123K-303K) reveals inverse relationship between sensitivity and operating temperature. Highest sensitivity of 49.2% is obtained at 123 K for 635 nm laser at power density of 1.4 mW/mm(2). Unlike sensitivity, response- and recovery-time demonstrate directly proportional dependence with operating temperature. Power dependent studies establish linear relation between power-density and sensitivity, and a safe limit beyond which sample heating prolongs the recovery time. Wavelength-dependent studies shows that proposed sensor can efficiently operate from visible to near NIR region. To the best of our knowledge such rGO based optical sensor performance at low temperature had not been reported earlier.
41. 41
  Kickelbick, G. Hybrid Materials: Synthesis, Characterization and Applications; Wiley-VCH: Weinheim, 2007.
  There is no corresponding record for this reference.
42. 42
  Pouretedal, H. R.; Kadkhodaie, A. Synthetic CeO₂ nanoparticle catalysis of methylene blue photodegradation: kinetics and mechanism. Chin. J. Catal. 2010, 31, 1328– 1334, DOI: 10.1016/S1872-2067(10)60121-0
  There is no corresponding record for this reference.
43. 43
  Kusuma, K. B.; Manju, M.; Ravikumar, C. R.; Raghavendra, N.; Shilpa Amulya, M. A.; Nagaswarupa, H. P. Photocatalytic degradation of methylene blue and electrochemical sensing of paracetamol using cerium oxide nanoparticles synthesized via sonochemical route. Appl. Surf. Sci. 2022, 11, 100304 DOI: 10.1016/j.apsadv.2022.100304
  There is no corresponding record for this reference.
44. 44
  Sehar, S.; Naz, I.; Rehman, A.; Sun, W.; Alhewairini, S. S.; Zahid, M. N.; Younis, A. Shape-controlled synthesis of cerium oxide nanoparticles for efficient dye photodegradation and antibacterial activities. Appl. Organomet. Chem. 2021, 35, e6069 DOI: 10.1002/aoc.6069
  44
  Shape-controlled synthesis of cerium oxide nanoparticles for efficient dye photodegradation and antibacterial activities
  Sehar, Shama; Naz, Iffat; Rehman, Abdul; Sun, Wuyang; Alhewairini, Saleh S.; Zahid, Muhammad Nauman; Younis, Adnan
  Applied Organometallic Chemistry (2021), 35 (1), e6069CODEN: AOCHEX; ISSN:0268-2605. (John Wiley & Sons Ltd.)
  Herein, two-shaped cerium oxide nanoparticles (NPs), i.e., spherical and cubical, were synthesized through hydrothermal approach by tuning reaction temps. The morphol. and structural and chem. compn. of both samples were characterized by transmission electron microscopy (TEM), high-resoln. TEM (HRTEM), X-ray diffraction (XRD), and XPS, resp. Both types of NPs were subjected to photodegrdn. of industrial dye, methylene blue, under dark, sunlight, and UV irradn., and their recyclability and reusability were also assessed. Besides, the effect of pH, concn. of NPs, and dye on degradability was also analyzed. The cubical-shaped NPs demonstrated superior degrdn. of ∼70% under UV irradn. than the spherical ones (<50%). The antibacterial activities of both NPs were also examd., and cubical-shaped NPs were found to exhibit superior antimicrobial potential (zone of inhibition [ZOI]: 25.75 ± 0.25, 18.83 ± 0.76, 15.75 ± 0.66, and 15.75 ± 0.25 mm) in comparison with the spherical ones (ZOI: 19.41 ± 0.94, 14.25 ± 0.66, 12.58 ± 1.01, and 9.91 ± 1.01 nm) for Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Staphylococcus aureus resp. with reduced growth and viable count. This difference in performance may be attributed to the higher surface areas of cubical-shaped NPs and higher content of oxygen vacancies. The results presented in this study suggest that cubical NPs are excellent candidates for treating industrial wastewater with greater reproducibility. Moreover, they can be used as active growth inhibitors against different microorganisms and thus can be extremely useful in developing medical devices and to design various antimicrobial systems.
45. 45
  Murugan, R.; Kashinath, L.; Subash, R.; Sakthivel, P.; Byrappa, K.; Rajendran, S.; Ravi, G. Pure and alkaline metal ion (Mg, Ca, Sr, Ba) doped cerium oxide nanostructures for photo degradation of methylene blue. Mater. Res. Bull. 2018, 97, 319– 325, DOI: 10.1016/j.materresbull.2017.09.026
  45
  Pure and alkaline metal ion (Mg, Ca, Sr, Ba) doped cerium oxide nanostructures for photo degradation of methylene blue
  Murugan, R.; Kashinath, L.; Subash, R.; Sakthivel, P.; Byrappa, K.; Rajendran, S.; Ravi, G.
  Materials Research Bulletin (2018), 97 (), 319-325CODEN: MRBUAC; ISSN:0025-5408. (Elsevier Ltd.)
  Pure and alk. metal ion (Mg, Ca, Sr, Ba) doped Cerium oxide nanostructures were successfully synthesized by hydrothermal method. The structural, optical and compositional studies of the prepd. nanoparticles were undertaken by X-ray diffraction (XRD), Fourier transform IR spectroscopy (FTIR), photoluminescence (PL), Raman, XPS and TEM analyses. The photocatalytic activity of prepd. nanoparticles was analyzed using methylene blue dye. XRD pattern reveals that the prepd. nanoparticles are polycryst. nature and there is no any byproduct related peaks were obsd. for the doped samples. The incorporation of dopants into the CeO2 nanoparticles was confirmed through PL, Raman and XPS spectra. The enhanced photocatalytic activity for the alk. metal doped samples was obsd. compared to pure cerium oxide nanoparticles.
46. 46
  Neelgund, G. M.; Oki, A. Graphene-coupled ZnO: A robust NIR-induced catalyst for rapid photo-oxidation of cyanide. ACS Omega 2017, 2, 9095– 9102, DOI: 10.1021/acsomega.7b01398
  46
  Graphene-Coupled ZnO: A Robust NIR-Induced Catalyst for Rapid Photo-Oxidation of Cyanide
  Neelgund, Gururaj M.; Oki, Aderemi
  ACS Omega (2017), 2 (12), 9095-9102CODEN: ACSODF; ISSN:2470-1343. (American Chemical Society)
  Herein, we report the modulation of ZnO for enhancement of its ability toward plasmonic absorption of near-IR (NIR) photons through coupling of graphene (GR). The reported modification led GR-ZnO to be a promising photocatalyst by the complete removal of poisonous and nonvolatile potassium cyanide from water. The photocatalytic degrdn. of cyanide was revealed by exposing it to NIR laser radiation and comparing with the rate of UV, visible, and sunlight using their apparent reaction rate consts. derived from the Langmuir-Hinshelwood simulation, physicochem. The heteronanostructured GR-ZnO promoted rapid photo-oxidn. of cyanide under illumination with NIR laser radiation rather than UV, visible, and sunlight. It was assessed that the photothermal effect (PTE) is the main cause for higher catalytic efficiency of GR-ZnO in the presence of NIR radiations. Except for the NIR radiations, GR-ZnO does not show any indication of PTE by irradiating with UV, visible, or sunlight. On account of its significance, the PTE of GR-ZnO in KCN soln. was evaluated and compared with its individual components viz., GR and ZnO upon exposure to a 980 nm laser radiation system. Furthermore, it has been revealed that the PTE of GR-ZnO was proportional to its concn. In addn. to its effectiveness in the degrdn. of cyanide, GR-ZnO retained its special structure and exhibited an outstanding photostability after its repeated use in three successive cycles.

Efficient Photocatalytic Degradation of Methylene Blue Dye from Aqueous Solution with Cerium Oxide Nanoparticles and Graphene Oxide-Doped PolyacrylamideClick to copy article linkArticle link copied!

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Abstract

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1. Introduction

2. Experimental Section

2.1. Chemicals

2.2. Preparation of CeO2-NPs and GO-Doped PAM Hydrogels

Figure 1

2.3. Characterization of the CeO2-NPs/GO/PAM Hydrogel

2.4. Photocatalytic Degradation Experiments and Mineralization Studies

2.5. Quencher Experiments of the CeO2-NPs/GO/PAM Hydrogel

2.6. Determination of the Point of Zero Charge (PZC)

3. Results and Discussion

3.1. Characterization of the CeO2-NPs/GO/PAM Hydrogel

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

3.2. Effect of the Amounts of CeO2-NPs and GO on Photocatalytic Degradation

Figure 9

3.3. Effect of pH and the Initial Concentration of MB Solution

Figure 10

3.4. Effect of the Type of Light Irradiation

Figure 11

3.5. Photocatalytic Degradation Mechanism of MB Dye by CeO2-NPs/GO/PAM

Figure 12

Figure 13

3.6. Methylene Blue (MB) Mineralization

3.7. Kinetic Modeling of Dye Degradation

Figure 14

3.8. Reusability of CeO2-NPs/GO/PAM Hydrogels

Figure 15

4. Conclusions

Author Information

Acknowledgments

References

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Abstract

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References

Efficient Photocatalytic Degradation of Methylene Blue Dye from Aqueous Solution with Cerium Oxide Nanoparticles and Graphene Oxide-Doped Polyacrylamide
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2.2. Preparation of CeO₂-NPs and GO-Doped PAM Hydrogels

2.3. Characterization of the CeO₂-NPs/GO/PAM Hydrogel

2.5. Quencher Experiments of the CeO₂-NPs/GO/PAM Hydrogel

3.1. Characterization of the CeO₂-NPs/GO/PAM Hydrogel

3.2. Effect of the Amounts of CeO₂-NPs and GO on Photocatalytic Degradation

3.5. Photocatalytic Degradation Mechanism of MB Dye by CeO₂-NPs/GO/PAM

3.8. Reusability of CeO₂-NPs/GO/PAM Hydrogels