ACS Publications. Most Trusted. Most Cited. Most Read
My Activity
CONTENT TYPES

Figure 1Loading Img

Spectral Emissivity Profiles for Radiative Cooling

Cite this: ACS Appl. Opt. Mater. 2023, XXXX, XXX, XXX-XXX
Publication Date (Web):June 21, 2023
https://doi.org/10.1021/acsaom.3c00092

© 2023 The Authors. Published by American Chemical Society. This publication is licensed under

CC-BY 4.0.
  • Open Access

Article Views

1667

Altmetric

-

Citations

-
LEARN ABOUT THESE METRICS
PDF (4 MB)

Abstract

Passive radiative cooling, an innovative approach for cooling buildings and devices, has attracted considerable attention in recent years. In particular, the spectral emissivity distribution of surfaces plays a crucial role for an object to radiate at wavelengths for which the atmosphere is transparent and solar irradiance is low. Here, we study the role of spectral emissivity distributions using different performance metrics: cooling power (CP) and equilibrium temperature (TEq). We investigated the roles of environmental factors, such as ambient temperature and level of thermal insulation from surroundings, on spectral emissivity distributions. Based on these emissivity distributions, we report the conditions at which the suitable profile for cooling power maximization and equilibrium temperature minimization changes. We discuss the realization of spectral emissivity distributions using various optical materials for cooling power maximization and equilibrium temperature minimization separately under different environmental conditions. The impacts of material selection on the realization of desired emissivity profiles and corresponding outcomes are analyzed. As progress in this emerging field gains traction, development of radiative cooling structures with suitable spectral emissivity profiles under different circumstances will become essential.

This publication is licensed under

CC-BY 4.0.
  • cc licence
  • by licence

SPECIAL ISSUE

This article is part of the Optical Materials for Radiative Cooling special issue.

1. Introduction

ARTICLE SECTIONS
Jump To

Passive radiative cooling, a heat exchange mechanism which occurs between terrestrial objects and the outer sky via the atmospheric transmission window, has attracted significant interest as the demand for energy efficient cooling solutions increases. Although the concept of radiative cooling below ambient air temperature was initially demonstrated in the mid 1970s (1) for nighttime conditions, its demonstration under direct sunlight in 2014 (2) reignited the interest of researchers. It was shown that selective engineering of the spectral properties of the surface is a core requirement for radiative cooling during both nighttime and daytime. The fundamental mechanism that allows radiative cooling, independently from operation time, is the simultaneous emission of thermal radiation in the 8–13 μm range at which surfaces with temperatures around 300 K radiate (3) and suppression of absorption at shorter and longer wavelengths prevent absorption of atmospheric thermal radiation. (4) Even though the suppression of absorption in the 4–8 μm range and wavelengths longer than 13 μm are sufficient to prevent a significant portion of the radiation from the atmospheric contributions, absorption at wavelengths shorter than 4 μm must be strongly suppressed to avoid the absorption of solar irradiance, which is present during the daytime. Based on these requirements, a selective profile is proposed and realized with a multilayer structure and shown to be effective in achieving steady state temperature below ambient under direct sunlight. (2) In the following years, many different types of structures have been proposed in the literature. (5−11) In addition to these fundamental studies on various types of structures, the integrations of radiative cooling structures with photovoltaics (12−14) and buildings (15−21) were reported. Because of the thermal insulation requirement of radiative cooling, progress in development of thermal covers has been a research field of interest. (22−24) Considering the variations in demand during seasonal transitions, structures with dynamical radiative cooling capabilities were explored. (25−31) Challenges toward the commercialization of radiative cooling were also discussed in the literature. (32,33)
After successful demonstrations of radiative cooling with a variety of structures, a few studies are focused on the role of emissivity profiles on the performance of radiative cooling. (9,34,35) Especially in ref (35), different types of emissivity profiles are discussed in detail which leads to lower equilibrium temperatures under different conditions. In the light of these discussions regarding the emissivity profiles, existing literature should be reassessed in detail with the consideration of the applicability of the proposed structures in achieving the altered emissivity profiles. Radiative cooling performances of different emissivity profiles have been demonstrated experimentally, which provides an idea about the limits that can be achieved through radiative cooling. In ref (36), steady state temperature lower than ambient by 40 °C is achieved with a structure that only has a strong emission in the 8–13 μm range. Later, it is shown that using a narrowband emission profile instead of selectively emitting in the 8–13 μm range can lead to temperature reductions of 100 °C below ambient temperature. (35,37) However, it is shown that achieving such extreme low temperatures requires near-complete thermal isolation of nonradiative heat exchange mechanisms. Considering the challenge in achieving such high isolation, necessary modifications to emissivity profiles are analyzed in refs (9and35), and the need for broadening the emission spectrum is demonstrated. In addition to temperature reduction, the possible differences in emissivity profiles are also reported when the cooling power of the surface is of interest.
Many different materials and system architectures can be used to realize these emissivity profiles. These material systems are enabled by advancements in computational design, fabrication, and characterization tools of optical structures. (38−51) Multilayers, micro/nanoparticle-embedded polymeric coatings, and polymers with artificially engineered porosities are among some of the structures that are utilized for radiative cooling purposes. Layered structures which consist of a combination of different materials are one of the simplest, yet very effective, ways of realizing the desired emissivity profile for radiative cooling. (2,52−58) Usually, materials with strong absorption in the 8–13 μm wavelength range and near-lossless in the visible and near-infrared spectra, such as SiO2, Al2O3, TiO2, HfO2, (59) are used together with a metal which provides broadband reflection. Tailoring of the interference of the propagating wave components inside the structure is the fundamental mechanism that leads to target spectral characteristics. Although many of the proposed multilayer structures are composed of periodically alternating layers of high–low index materials, (2,52,53,60,61) various numerical methods optimize the layer thicknesses together with the selected materials from a predefined material library. (53,62,63) However, while designing multilayers, especially with a combination of different materials, possible fabrication challenges and the feasibility of extension to large scale should be considered. A simple structure proposed in the literature addresses such challenges, (64) which is composed of a single PDMS layer on top of Ag. Such a simple structure is shown to be effective in achieving radiative cooling below ambient temperature, which exhibits an 8 °C lower surface temperature than ambient temperature, with 127 Wm2– cooling power at ambient temperature.
As an alternative to the aforementioned stacked layers, it is shown that radiative cooling performance of single layered coatings can be further improved by embedding micro/nanoparticles. (65−73) The first experimental demonstration of such a structure is reported in 2017, (73) for which a cooling power of nearly 95 Wm2– is reported. The major advantage of this type of structure over layered structures is its feasibility for large scale production. Following the successful demonstration of a particle-based structure on passive radiative cooling in the daytime, different configurations of micro/nanoparticle-based polymeric structures composed of mixtures of different materials have been reported in recent years. Although most of these structures are suitable for large scale fabrication, they still require a metallic back reflector to satisfy increases in the fabrication steps, thus hindering the feasibility of extension to large scale.
Metamaterials consisting of periodically arranged surface textures are among other widely used methods to achieve radiative cooling. (74) Due to their capability of exciting different resonance mechanisms, e.g., lattice and plasmonic resonances, (75−81) they are excellent candidates for satisfying the strong emission in the 8–13 μm wavelength interval. In fact, the first theoretical demonstration of daytime passive radiative cooling is done by a multilayer structure combined with a periodically arranged surface texture. (82) A two-dimensional periodic array of square air holes composed of SiC and SiO2 are used to excite phonon–polariton resonances of these materials in the 8–13 μm interval. The resulting emission spectrum provides near-perfect emission in the 8–13 μm range, as well as the other possible atmospheric transparency window located in the 15–25 μm interval. The major drawback of this structure despite its excellent spectral selectivity is the strong absorption in the visible spectrum due to SiC, which increases the heat load in the system. Following this idea, structures that utilize various types of grating like patterns are proposed (83−88) which allow controlling the wave–matter interaction at smaller geometries. It is also shown that broadband absorption achieved by stacking individual resonators in a trapezoidal fashion (89) can be utilized for radiative cooling purposes by designing a broadband selective absorber. (90) In addition, 2D metamaterials are widely used as radiative cooling structures to be integrated with devices that demand cooling, e.g., solar cells. (91−95) Because of their excellent spectral selectivity, metamaterials comply well with the devices’ spectral requirements as well as the radiative cooling requirements. The same characteristic of metamaterials allows tailoring spectral characteristics for addressing other practical requirements such as colorization for aesthetic purposes. Recently, there has been increased attention to colored radiative cooling coatings (96−108) for which many types of metamaterials are proposed as great solutions thanks to their capability of selective spectral engineering.
A recently proposed type of polymeric structure at which porosity of the polymer was artificially engineered was shown to be effective in achieving solar irradiance reflection and emission in the atmospheric transparency window simultaneously. (109−116) While holes inside the structure act as a cavity at longer wavelengths, they exhibit a large bandgap and lead to broadband reflection in visible and near-infrared spectra at which solar irradiance is strong. Eliminating the need for an additional metallic layer is a major step toward large scale fabrication feasibility, thus allowing practical realization of passive radiative cooling coatings with readily available approaches and formats, such as paints. (117)
Parallel to research related to structural characteristics, there is also ongoing active research regarding the possible materials for use in radiative cooling coatings. (6,10,17,118,119) In ref (118), different candidate materials are reported not only for their spectral characteristics but also for their thermomechanical characteristics. Progress in this aspect of the field is equally important in terms of the development of radiative coolers with superior performances and characteristics for specific applications, e.g., buildings and solar cells. A recent example for a material aspect in the field is related to the use of plasmonics for colorization of a radiative cooling structure. (120)
There are extensive efforts to adapt the materials and structures that already exist in biological creatures or in the nature. (121−124) In 2015, right after the first experimental demonstration of daytime passive radiative cooling in 2014, (2) it was shown that Saharan silver ants already benefit from daytime passive radiative cooling. (125) With the dense array of triangular hairs on their body, they are able to strongly reflect incident solar irradiance while emitting thermal radiation in the infrared spectrum simultaneously. A major advantage of such discoveries is that they provide excellent guidelines for future studies in the field. For instance, following ref (125), many artificially engineered structures that are inspired by Saharan ants were reported. (126−129) Another advantage of such bioinspired structures is that they provide candidate materials that are feasible for large fabrication and low cost and are ecofriendly. For instance, it was shown that through delignification and densification of natural wood, a mechanically strong highly efficient radiative cooling structure can be obtained. (130) Cellulose nanofibers are held responsible from high backscattering of solar irradiance and emission in mid-infrared wavelengths. After the demonstration of the potential of cellulose as a material for radiative cooling, many other works that propose cellulose-based radiative coolers were demonstrated. (131−136) Many other types of bioinspired structures and materials were also reported up to this date, (137−145) including studies based on near-field radiative transfer. (146,147) Finally, the radiative cooling capability of natural silk (148) opens the way for realizing radiative cooling phenomenon in textiles. (149−158) Successful demonstrations of radiative cooling with textiles considerably enlarges the application area and its potential contribution to energy consumption in general.
Despite the vast progress made in the field regarding the implementation of radiative cooling structures, the connection between the spectral characteristics of the coatings and radiative cooling dynamics is not explored in detail. More explicitly, the impact of spectral characteristics from the visible to far-infrared portions of the electromagnetic spectrum on the radiative characteristics, such as cooling power, PCool, and equilibrium temperature, TEq, should be well considered. In addition, dependency of spectral requirements both for PCool maximization and TEq minimization, under various circumstances (ambient temperature and level of thermal insulation from the environment) must be well defined, (35) to develop radiative cooling structures that are more suitable to practical needs. Once the impact of environmental conditions on the spectral profiles are defined, estimates of theoretical limits can be created, and how close we can approach those limits can be observed.
In this work, starting with the fundamentals of radiative cooling and definition of its performance metrics, PCool and TEq, we studied the role of spectral emissivity of a surface on those under different conditions. Then, we designed 1D photonic multilayers specifically to maximize PCool and minimize TEq similar to the method described in ref (53) as a measure of how much we can approach the theoretically estimated limits. Structures are designed with different materials to discuss the role of optical properties on achieving desired spectra for PCool maximization and TEq minimization. Finally, we conclude with a brief summary.

2. Fundamentals of Radiative Cooling

ARTICLE SECTIONS
Jump To

Radiative cooling is a passive phenomenon that benefits from the tremendous temperature difference between the sky, 3 K, and terrestrial objects. Due to this temperature difference, a considerable heat exchange occurs between the sky and terrestrial objects. To properly analyze a radiative cooling system, other radiative heat exchange mechanisms, such as solar irradiance and atmospheric thermal radiation, should also be taken into account. Earth receives a high amount of thermal radiation from the Sun, reaching up to 1000 Wm2– levels at certain locations. A significant portion of the incident solar radiation is confined in visible and near-infrared spectra. In addition to solar irradiance, gas molecules in the Earth’s atmosphere also emit thermal radiation. Therefore, together with the spectral characteristics of the radiation from terrestrial objects, characteristics of incoming radiation from various sources should be considered.
With the knowledge of the characteristics of these radiation mechanisms, their behaviors can be modeled and used to define the net heat exchange occurring on the surface, which determines the cooling power of the surface. In a similar manner, the temperature of the surface at equilibrium or steady state temperature can be estimated. These two are the most commonly used metrics to compare the performances of different radiative cooling systems. Therefore, the definition of cooling power and equilibrium temperature, as well as understanding of the parameters they are dependent on, are crucial for development of radiative cooling structures.

2.1. Cooling Power and Equilibrium Temperature

Cooling power of a surface is defined as the required energy exchange rate, in the form of heating or heat removal, to keep the temperature of the surface constant. (159) The net cooling power, PCool, of a surface is mathematically defined in terms of ingoing and outgoing energy components that cause a change in the temperature of the surface
PCool(Ts)=PRad(Ts,εs)PAtm(TAmb,εs,εAtm)PSun(εs)
(1)
where PRad is the radiation from the surface, PAtm is the absorbed atmospheric thermal radiation, and PSun is the absorbed solar irradiance. Nonradiative contributions can be included in eq 1 by adding PConv = hc(TsTAmb) and qi, where PConv is the heat flux due to convective heat transfer between the surface and ambient temperature, and qi is the heat generated by the system during its operation. With these additional contributions, the net cooling power of a surface is defined as
PCool(Ts)=PRad(Ts,εs)PAtm(TAmb,εs,εAtm)PSun(εs)+PConvqi
(2)
From eq 2, for PCool maximization at any Ts, outgoing heat flux, PRad, must be maximized while total incoming flux, PAtm, PSun, PConv, and qi, must be minimized through engineering of εs.
Equilibrium temperature, TEq, on the other hand, is defined as the temperature at which heat exchange between the surface and its environment no longer occurs. This condition is mathematically expressed as
PCool(TEq)=0PRad(TEq,εs)=PAtm(TAmb,εs,εAtm)+PSun(εs)PConv+qi
(3)
As seen, the condition given in eq 3, the condition for TEq minimization is significantly different than the PCool maximization. In the case of TEq minimization, incoming heat flux should be minimized such that it is compensated by outgoing flux, the radiation from a surface at temperature TEq. In other words, maximum PCool is achieved when the difference between incoming and outgoing heat fluxes are maximized, whereas TEq is minimized when incoming heat flux is minimum.
As seen, both PCool and TEq are strongly dependent on the radiation characteristics from the surface that is cooling of interest, as well as the heating inputs that are acting on the surface. Therefore, it is crucial to understand the characteristics of both radiative and nonradiative components to maximize and minimize the PCool and TEq.

2.2. Understanding the Dynamics of Radiative Components and their Role in CP and TEq

As discussed in the previous section, when a surface is exposed to the sky, contributions from atmospheric thermal radiation and solar irradiance should be considered during the heat exchange analysis. In general, both solar irradiance and atmospheric thermal radiation are dependent on geographical conditions as well as the time of the year. Mathematical expressions for the atmospheric thermal radiation and solar irradiance are available and extensively used in the analysis of radiative cooling, which are given as
PAtm(TAmb,εs,εAtm)=AdΩcosθ0dλIBB(TAmb,λ)εAtm(λ,θ)εs(λ,θ)
(4)
PSun(εs)=A0dλIAM(λ)εs(λ,θ)
(5)
where ∫dΩ = 2π∫0π/2 sin θ. TAmb and εAtm stand for ambient air temperature and emissivity of the atmosphere, respectively, which are modeled as 1 – (tAtm)1/cos θ where tAtm is the transmissivity of the atmosphere. As seen from eqs 4and 5, PAtm is modeled as radiation from a diffusive surface at ambient temperature whereas solar irradiance is assumed to be direct and therefore has no angular integral. For both cases, it is assumed that εs (λ,θ) is equal to angular and spectral absorption, αs(λ,θ), of the surface according to Kirchhoff’s law of thermal radiation. In Figure 1(a), typical solar irradiance and atmospheric thermal radiation when TAmb = 300 K are shown together with the tAtm. As seen, solar irradiance is highly confined in the visible spectrum, 0.3–0.7 μm interval, and significantly lower at longer wavelengths. On the other hand, atmospheric thermal radiation takes place at longer wavelengths, from 5 to 25 μm with a low radiation region in the 8–13 μm range, which is referred to as atmospheric transparency window. These two components are usually considered as fundamental radiative heat loads acting on the surface when exposed to the sky. Spectral distribution of these sources determines the spectral emissivity requirement for radiative cooling, together with the emitted radiation from the surface, PRad, for which the mathematical expression is given as
PRad(Ts,εs)=AdΩcosθ0dλIBB(Ts,λ)εs(λ,θ)
(6)

Figure 1

Figure 1. (a) Solar irradiance (red), transmission of the atmosphere (blue), and atmospheric thermal radiation at TAmb = 300 K (green). (b) Blackbody radiation from a surface at increasing temperatures, Ts = 280,300 and 320 K at 5–25 μm spectrum interval.

The sources of the difference between PRad and PAtm are as follows: The difference between the radiation temperatures, Ts and TAmb, and the contribution of εAtm (λ,θ) only affects PAtm. Since εAtm (λ,θ) is always lower than 1, PAtm will always be lower than PRad when TsTAmb, because of the spectral distributions of IBB (Ts,λ) and IBB (TAmb,λ) as depicted in Figure 1(b).
Based on these characteristics of PRad, PAtm and PSun have spectral requirements for the purpose of PCool maximization and TEq minimization through passive radiative cooling. It is important to note that nonradiative dynamics should also be considered during the derivation of the spectral requirements, since they have significant effects on the total heat load acting on the surface.

3. Spectral Requirements of Radiative Cooling

ARTICLE SECTIONS
Jump To

In this section, we analyze the resulting PCool and TEq differences of the two different emissivity profiles, which are referred to as selective and broadband emission profiles, as shown in Figure 2(a). The selective profile depicted in Figure 2(a) is considered as the ideal profile for radiative cooling below ambient air temperature. The other profile, which has unity emission after 8 μm, is considered in the literature for cooling of the systems with relatively higher temperatures. As a reference point, we started analysis of these profiles by setting hc = qi = 0. With this condition, the surface’s cooling power and TEq are calculated under the assumption of an isolated system from the nonradiative heat exchange. In such a case, TEq values for those profiles are 204 and 256 K, and they exhibit different PCool values, especially at higher temperatures than TAmb. In terms of TEq reduction, a selective profile yields significantly better performance than the broadband profile when the system is isolated. However, it is not a very realistic scenario considering the challenges in achieving such an extreme thermal isolation. In fact, radiative coolers are designed to be integrated to the systems that heat up during their operation and require cooling. Therefore, generated heat from the system must be transferred to the radiative cooler and emitted away, which leads to qi ≠ 0. Such a condition may cause changes in the required spectral profiles, e.g., transition to selective to broadband, as in ref (93). Therefore, it is important to understand how spectral requirements vary with respect to external factors for understanding the limits of the radiative cooling.

Figure 2

Figure 2. (a) Selective emission, ε(λ) = 1 when 8 < λ < 13 μm and ε(λ) = 0 elsewhere, and broadband emission, ε(λ) = 1 when λ > 8 μm and ε(λ) = 0 λ < 8 μm profiles. (b) Corresponding TsPCool(Ts) curves for the selective and broadband emission profiles.

To analyze the changes in spectral requirements, especially to find the transition point from the selective to broadband profile, outcomes of those profiles are analyzed under different conditions. For analysis purposes, we introduce the term PL, which stands for the total head load acting on the surface, e.g., all heat contributions coming from absorption of solar irradiance and atmospheric thermal radiation, as well as nonradiative contributions, and it can be mathematically expressed as PL = PAtm(TAmb,εs,εAtm) + PSun (εs) + qi + PConv.

3.1. PCool Maximization

Cooling power is maximized when the difference between PRad and PL is maximum. Here, it is important to note that when Ts > TAmb, PConv will contribute positively to PCool, whereas it will be the opposite when Ts < TAmb. In addition, it is already shown that when TsTAmb, PRad will always be higher than PAtm, leading to higher PCool. Based on these, the following two cases are analyzed for selective and broadband profiles.

3.1.1. TS < TAmb

When Ts < TAmb, unlike the opposite scenario, PRad is not unconditionally higher than PAtm, but will be highly dependent on spectral distributions of εs and εAtm. In such a case, εs should be engineered such that it is minimum at the wavelengths at which atmospheric thermal radiation, IBB (TAmb,λ) εAtm (λ,θ), is high so that the surface does not absorb more power than it emits. From these, it appears that achieving a positive PCool requires more strict spectral requirements when Ts < TAmb. As seen, for the selective profile, εs is zero when εAtm (λ,θ) is high, TAtm (λ,θ) is low, and it is maximum elsewhere. If the surface had strong emission at λ > 13 μm, it would absorb more power coming from atmospheric thermal radiation. In addition, since Ts < TAmb, emitted radiation at λ > 13 μm would be lower than absorbed atmospheric thermal radiation. Therefore, the surface does not benefit from emitting radiation at λ > 13 μm at all, which makes selective emission profile superior compared to the broadband profile in terms of PCool maximization. It is also apparent when the TsPCool curve depicted in Figure 2(b) is considered. As seen, when Ts < TAmb, the selective emission profile exhibits higher PCool.

3.1.2. TSTAmb

When TsTAmb, PRad will always be higher than PAtm because of the characteristics of thermal radiation from surfaces. Considering the radiation at λ > 13 μm, PRad can benefit from radiation at those wavelengths, despite the characteristics of atmospheric transparency. Therefore, when the TsPCool curve for the broadband profile is considered, PCool is higher for the broadband profile at temperatures higher than ambient temperature, compared to the selective emission profile. This reasoning is valid any TAmb, hc, and qi because those characteristics do not alter the radiation characteristics that are considered for this conclusion. Therefore, PCool maximization surfaces can benefit from radiation at λ > 13 μm, if the surface temperature is above the ambient temperature.

3.2. TEq Minimization

Although the PCool enhancement problem can be mathematically considered as maximization of a difference, max(PRadPL), it is not the case for TEq minimization. In fact, TEq minimization should be treated as a minimization problem, min(PL), so that it can be compensated by PRad(TEq). Physically speaking, TEq is the temperature at which radiation from the surface (only outgoing radiative channel for heat exchange, if Ts is below ambient) compensates all heat load present in the system. Therefore, emission can be treated as the radiative heat load if the system is strictly minimized. This is in contrast to the case for PCool maximization.
In the case of a near-complete isolation of the system as depicted in Figure 3(a), hcqi ≈ 0, and with complete reflection in the entire electromagnetic spectrum, TEq can be reduced to extremely low values. In such a case, PL will be very low, considering PAtmPSun ≈ 0 due to near-complete reflection; therefore, even a very small amount of thermal radiation from the surface can compensate for PL. To analyze such a scenario, a new emissivity profile, referred as the narrowband, is created as seen in Figure 3(b). As opposed to the selective emissivity profile, emission occurs in a narrower wavelength interval, 10–12 μm. When hcqi ≈ 0, only heat load in the system will be due to PAtm, which is 1.9 W/m2. It means that the temperature, Ts, that satisfies the following, PRad(Ts,εNarrowband)=PAtm(Ts,εNarrowband,εAtm)=1.9Wm2 will be TEq. When TsPCool curves are constructed for these three profiles, TEq for the narrowband profile is obtained as 170 K which is nearly 35 K lower than that of the of selective profile. TEq for the broadband profile is 256 K, which is significantly higher than both. Since hcqi ≈ 0, reflection is set to unity until 8 μm for each case; therefore, PSun is almost equal for each. The only difference between heat loads acting on the surfaces stems from PAtm values which are 1.9, 16.2, and 167 Wm2–. When PAtm = 1.9 Wm–2, radiation at 170 K is sufficient to compensate. On the other hand, as PAtm increases, the heat load acting on the system can be compensated only with radiation at higher temperatures, leading to higher TEq. This example demonstrates the impact of heat load on the TEq.

Figure 3

Figure 3. (a) Schematic representation of a thermally closed system.(b) Comparison of selective, broadband, and narrowband emissivity profiles. (c) Corresponding TsPCool profiles for selective, broadband, and narrowband emissivity profiles with TEq points marked. (d) Change of TEq with increasing q for selective, broadband, and narrowband emissivity profiles.

To analyze the performance of the narrowband profile when PL ≫ 0, q is increased gradually to simulate a heat load increase on the surface, and corresponding TEq values are calculated. As seen in Figure 3(d), when q is above 10 Wm2–, TEq for the narrowband profile becomes higher than that of the selective profile. This indicates that, in the presence of a slight deviation from the complete reflection requirement in the visible and near-infrared spectra, the narrowband profile will lose its advantage over the selective profile. When such a strict requirement is considered together with the difficulty of realizing such a profile, utilizing the narrowband profile to cool the system purely with radiative cooling becomes infeasible.
When near-complete isolation is not the case, the PL ≫ 0, surface should emit more thermal radiation to compensate for the thermal load acting on the system; therefore, the selective profile becomes more suitable compared to the narrowband profile. Similar to the threshold for switching from the narrowband to the selective profile, a critical heat load, PCrit, can be defined to estimate the transition point from the selective to broadband emission profiles. In Figure 4, TEq values for increasing qi are plotted for selective and broadband emission profiles for different TAmb and hc values. The transition from the narrowband to broadband occurs when qi = 86 Wm2– at TAmb = 285 K, and when TAmb is increased to 310 K, transition occurs when qi = 127 Wm2–. The transition between the profiles occurs when the surface with the selective profile is not capable of compensating for the total heat load at a temperature lower than it would with a broadband profile. However, in the case of emission at λ > 13 μm, which leads to higher PRad, PAtm is also increased due to absorption of atmospheric thermal radiation at those wavelengths, which increases the total heat load acting on the system. Therefore, for the transition between profiles to occur, the rise in PRad should be greater than the increase in PAtm. It is already known that higher TAmb leads to higher PAtm. When TAmb is higher, the surface should emit more radiation to address for the increased PAtm which is only possible at higher temperatures for a fixed emissivity. Because of this, the transition occurs at larger qi for higher TAmb, which causes higher surface temperatures. This analysis reveals that the selective emission profile at higher TAmb is superior compared to the broadband profile up to higher heat loads.

Figure 4

Figure 4. TEq with respect to increasing q: (a) at fixed hc = 0 and increasing TAmb with transition points PCrit (green) from selective profile (blue) to broadband profile (red) and (b) at fixed TAmb = 297 K and increasing hc with transition points PCrit (black) from selective profile (green) to broadband profile (purple).

Trends are different for increasing hc for a fixed TAmb compared to fixed hc for rising TAmb. As seen in Figure 4(b), PCrit becomes lower with increasing hc. When there is no significant heat load acting on the system, the surface can maintain its low temperature, as shown when hcqi ≈ 0. However, with increasing hc, the surface starts to interact with its environment. As hc increases, the heat exchange rate will be higher and will dominate the radiative heat exchange mechanism, and TEq will converge to TAmb when hc ≫ 0. With increasing the heat exchange rate, the heat load acting on the surface will increase; therefore, the switch from a selective to broadband profile occurs earlier with qi as seen in Figure 4(b). Besides, due to the dominance of the nonradiative heat exchange, performances of the different emission profiles become indifferent. This indicates that in the presence of strong nonradiative heat exchange one may not have any benefit at all from radiative cooling. Therefore, it is highly crucial to consider the nonradiative cooling mechanisms used in the system of interest at which radiative cooling coatings are going to be implemented.
As seen in the results shown in Figure 4, TEq values remained around 300 K levels and reached their maximum when q becomes 250 Wm2–. Thermal radiation at such temperatures is mostly confined in the 8–13 μm wavelength interval, with relatively smaller contributions from shorter wavelengths. Therefore, the impact of emission at those shorter wavelengths on TEq is limited. However, at further elevated temperatures which can be achieved with higher q, the contribution from radiation at shorter wavelengths than 8 μm has considerable influence on the TEq. Therefore, emissivity profiles with unity emission starting from as low as 2.5 μm can provide significantly lower TEq than the broadband profile demonstrated above (with unity emission starting from 8 μm). When corresponding TEq values with increasing q for the profiles, depicted in Figure 5(a), have different starting points of unity emission, the impact of bandwidth of the unity emission on TEq can be better understood. As seen in Figure 5(b), the profile broadband II results in lower TEq values compared to the selective and broadband profiles when q becomes higher than 150 Wm2–, and the difference increases as q increases. When q reaches to 4 × 104 Wm2– levels, the broadband III profile becomes more superior than broadband II in terms of TEq. At such elevated temperatures, radiation emitted from the surface becomes even higher than the incident solar irradiance, which makes emission of thermal radiation even at the visible spectrum more advantageous. These analyses demonstrate the importance of the bandwidth of the unity emission depending on the total heat load acting on the system.

Figure 5

Figure 5. Comparison of selective and different broadband profiles with varying unity emission starting points. (b) Change of TEq with increasing q for selective and different broadband profiles.

4. Realization of Emission Profiles

ARTICLE SECTIONS
Jump To

For realization of the discussed spectral emissivity profiles, we designed multilayer structures with different material combinations to maximize PCool (T) and minimize TEq without predetermined spectral emission profiles. To achieve this, we used the method we previously proposed in ref (53). The layer numbers of the structures are fixed to 4, and thicknesses of alternating layers are used and optimized on top of a 100 nm Ag layer. SiO2–TiO2 and SiO2–Al2O3 pairs are used as layer materials, which are among commonly used materials in radiative cooling coatings. (2,52,53) The optical properties for SiO2, Al2O3 and TiO2 are retrieved from refs (160and161). Thicknesses for each designed coating with corresponding materials and conditions are listed in Table 2. Note that small k values in the visible and near-infrared spectra may result in considerable absorption of the solar irradiance and degrades the radiative cooling performance. However, such an outcome can be avoided by keeping layer thicknesses small, e.g., on the order of few micrometers, as seen in Tables 1 and 2. In Figure 6(a), spectral emission profiles when hc = 0 and qi = 0 are demonstrated for PCool (T) maximization and TEq minimization with different material pairs. As shown in Figure 6(a), the spectral profiles are similar for λ < 13 μm. However, for the spectral region λ < 13 μm, emission starts to decrease considerably for the structure optimized for TEq minimization, whereas it remains high for the structure optimized for PCool (T) maximization for SiO2–TiO2 pairs. Change in emissivity is not as strong as in the case of SiO2–TiO2 pairs, when SiO2–Al2O3 pairs are used. Corresponding PRad, PSun, and PAtm together with the average emission values are shown in Table 1. As depicted in Table 1, the total radiative heat load due to Psun and PAtm is increased by 38 Wm2–, from 62 to 100 Wm2–, when TiO2 is substituted by Al2O3. Such change stems from changes in average reflectivity in 0.3–8 and 13–25 μm. Even a 1% change in average reflection in 0.3–8 μm caused an increase of 15 Wm2– in PSun, and a 15% average reflection change in 13–25 μm results in an approximate 25 Wm2– raise in PAtm. Despite these changes, average reflection in the 8–13 μm range remained similar for these two structures; thus, additional heat load cannot be compensated with higher thermal radiation emission in the 8–13 μm spectrum, and higher TEq is observed when Al2O3 is used instead of TiO2. Based on the corresponding TsPCool curves depicted in Figure 6(b), TEq values of 244 and 262 K are achieved for SiO2–TiO2 and SiO2–Al2O3 pairs, respectively. These results emphasize the importance of material selection on TEq, which can cause approximately 20 K difference in TEq. It is important to note that TEq for the selective profile is around 205 K indicating that by further reducing the heat load even lower TEq values can be achieved.
Table 1. Corresponding Power and Average Reflection Percentages for Structures with Different Material Pairs, Designed for CP Maximization and TEq Minimization
 Power (Wm2–)Avg. Reflection ((λ))
TargetMaterial pairPRadPSunPAtmI (λI) (%)II (λII) (%)III (λIII) (%)
CPTiO2–SiO224213.23140.6191.525.829.8
CPAl2O3–SiO220425.71101.7793.529.437.7
TEqTiO2–SiO261.947.7454.295.127.770.2
TEqAl2O3–SiO2100.3922.2478.159428.856.5
Table 2. Layer Thicknesses in Coatings Designed for CP Maximization and TEq Minimization with Different Material Pairs for Varying Conditions
hc = 0, q = 0hc = 5 Wm2– K–1q = 400 Wm2–
 Max CPMin TEq Max CPMin TEq Max CPMin TEq
TiO20.192.92Al2O30.160.50TiO20.210.25
SiO22.520.59SiO21.171.32SiO22.622.14
TiO20.072.50Al2O31.321.18TiO20.130.26
SiO22.531.79SiO22.601.931SiO22.772.99
Ag0.10.1Ag0.10.1Ag0.10.1

Figure 6

Figure 6. (a) Calculated spectra for the structures: (I) SiO2–TiO2 pair designed for TEq minimization and CP maximization. (II) SiO2–Al2O3 pair designed for TEq minimization and CP maximization. (III) SiO2–TiO2 pairs designed for TEq minimization and CP maximization for hc = 5 Wm2– K–1 and q = 400 Wm2–. (b) TsPCool curves for the structures designed to minimize TEq and selective profile. (c) TsPCool curves for the structures designed to maximize PCool and broadband profile. (d) TsPCool curves for the structure with SiO2–TiO2 pair designed to minimize TEq and maximize CP.

When PCool (Ts = 300 K) is of interest but not the TEq minimization, the calculated final spectrum of the structure with SiO2–TiO2 pairs has changed from selective to broadband, to increase the PRad by emitting thermal radiation at λ > 13 μm. As seen in Figure 6(a), a drastic change is observed in the spectra, whereas it is not the case for the structure with SiO2–Al2O3 pairs. As tabulated in Table 1 ,the change in average reflectivity is around 40% for the former, whereas it is 20% for the latter. Final PCool (Ts = 300 K) is equal to 100 and 75 Wm2– for the structures with SiO2–TiO2 and SiO2–Al2O3, respectively, and it is approximately 140 Wm2– for the broadband profile, as shown in Figure 6(c). Finally, when the structure is designed to maximize PCool and minimize TEq when hc ≫ 0 and qi ≫ 0 with SiO2–TiO2 pairs, spectra shown in Figure 6(a) are achieved. As seen, no significant changes in the spectra are observed and corresponding TsPCool becomes indifferent. There is an 8 K difference in TEq for the broadband and the achieved profiles.
The differences between the observed outcomes for the structures with SiO2–TiO2 and SiO2–Al2O3 are related to differences between the optical properties between TiO2 and Al2O3. First, due to the refractive index differences in visible and near-infrared spectra, (59) as depicted in Figure 7(a), there are slight differences between the average reflectivity at these spectra, which causes an increase in PSun up to 15–20 Wm2– and leading to reduction in PCool and raise in TEq. As given in Table 1, the second major difference occurs at λ > 13 μm, where the real and imaginary parts of the refractive indices, n and k, respectively, of TiO2 and Al2O3 are drastically different. (59) Such differences in fact provide a good example to demonstrate the role of dispersion in optical properties of coating materials. Al2O3 has strong absorption peaks around 17 and 22 μm wavelengths, shown in Figure 7(d), which occurs due the sudden changes in both n and k of Al2O3. On the other hand, n and k of TiO2 is free of such resonance-like changes as seen in Figure 7(a) and (b); therefore, it exhibits near constant reflectivity after 15 μm as depicted in Figure 7(c). Due to such dispersive characteristics of Al2O3, it is challenging to suppress such absorption modes and satisfy high reflection at λ > 13 μm for TEq minimization, with the structure in consideration. In other words, required thicknesses to satisfy near-perfect impedance mismatch at 17 and 22 μm are significantly different than adjacent wavelengths due to the dispersion in Al2O3. Such differences can be visualized by considering reflection coefficients, Γ(λ > 13 μm), of Al2O3 and TiO2 as seen in Figure 7(e) and (f). As seen, distribution of Γ(λ > 13 μm) of Al2O3 is more dispersed compared to Γ(λ > 13 μm) of TiO2, due to the difference in dispersion in optical properties of these materials. Because of this property of Al2O3, it is relatively more difficult to achieve broadband reflection at λ > 13 μm with pairs of Al2O3–SiO2 compared to pairs of TiO2–SiO2, which leads to poorer performance in achieving selective emission profiles, thus lower TEq.

Figure 7

Figure 7. (a) Real parts of the refractive indices of TiO2 and Al2O3. (b) Imaginary parts of the refractive indices of TiO2 and Al2O3. (c) Reflection of single TiO2 medium. (d) Reflection of single Al2O3 medium. (e) Reflection coefficients of TiO2 on complex reflection plane. (f) Reflection coefficients of Al2O3 on complex reflection plane.

The dispersion characteristics of Al2O3 at λ > 13 μm are also the source of high average reflectivity which leads to lower PCool when hcqi ≈ 0 or higher TEq when hc ≫ 0 and qi ≫ 0 with the structure composed of Al2O3–SiO2 pairs. A similar challenge in achieving broadband reflection at λ > 13 μm due to the dispersion of Al2O3 also exists when broadband absorption/emission is desired. At this wavelength interval, although Al2O3 has higher absorption on average due to several absorption modes, increasing the absorption at nonhighly absorbing wavelengths while preserving the high absorption at adjacent wavelengths is challenging due to differences in Γ(λ). Due to weak dispersion characteristics in n and k of TiO2, achieving impedance matching in the broadband spectrum is simpler in the case of TiO2–SiO2 pairs; thus, higher PCool or lower TEq is achieved when hcqi ≈ 0 or hc ≫ 0, qi ≫ 0, respectively.

5. Conclusions and Remarks

ARTICLE SECTIONS
Jump To

Spectral requirements for radiative cooling may vary in the presence of heat generation or weak thermal isolation from the environment. It was shown that, as the heat load increases in the system, drastic changes in the ideal emission profile occur. In recent years, many types of coatings have been proposed and designed with spectral emission profiles that are very close to the selective emission profile. As the efficiency of the radiative cooling is demonstrated with experimental measurements below ambient air temperature under direct sunlight, research toward applicability of those coatings in large scale is accelerated. Although such a selective profile is better for achieving TEq below ambient temperature under extreme isolation, it is not the most appropriate profile for real applications at which such extreme isolation may not be realistic. Therefore, it is equally important to seek coatings that are closer to the broadband profile while studying the applicability of radiative cooling coatings in large scale.
It is well-known that any type of coating’s spectral characteristics is controlled by the material it is composed of and geometrical dimensions of the features it has. Usually, in most of the radiative cooling coatings, a metallic back reflector is used for broadband reflection, preventing solar irradiance and atmospheric thermal radiation absorption. Thermal radiation emission from the surface requirement is fulfilled by the materials which have strong absorption at radiation wavelengths, typically λ > 8 μm. It was also shown that both reflection of solar irradiance and thermal emission from the surface requirements can be simultaneously satisfied by utilizing micro/nanoparticle-embedded polymers through tailoring of scattering from the particles by control of their distribution inside the host polymer. Yet, most of the recent literature is focused on cooling below ambient temperature and uses the selective emission profile, but not the broadband emission profile, which is shown to be more appropriate for cooling at temperatures above ambient. Therefore, analysis of coating characteristics at wavelengths longer than 13 μm is crucial.
In addition, when the radiative cooling coating is not treated as a stand-alone system, requirements of the system that the radiative cooler is going to be integrated with comes into the picture, such as aesthetic, thermal, and electromagnetic. For instance, surface color becomes highly important when the coating is going to be integrated for use in cooling of buildings, which requires modifications of the coatings’ spectral characteristics in the visible spectrum. Many coatings have been proposed under the topic of colorful radiative cooling; however, their characteristics at λ > 13 μm are not explored in detail, which may require adjustments depending on the operating conditions. Besides the color, the applied coating should not reduce the performance of the other cooling or thermal isolation mechanisms. Cooling with either natural or forced convection is a widely utilized approach and proven to be effective. Therefore, materials of the radiative cooler should be chosen in accordance with the convective mechanisms.
Finally, the radiative cooling coating must comply with the systems’ electromagnetic requirements that it is going to be integrated with. Some examples of such systems include solar cells, which harvest energy from visible and near-infrared spectra, and telecommunication systems, which receive and transmit microwave/RF signals. Therefore, any radiative cooling materials should be chosen by considering their electromagnetic properties at different portions of the electromagnetic spectrum of interest. All types of these additional requirements bring extra constraints that should be addressed during the design stage of the radiative cooler. Considering the significant progress made in the field of radiative cooling and advancements in micro/nanotechnology, knowledge in the field is mature enough to be extended to application-dependent development of feasible radiative cooling structures.

Author Information

ARTICLE SECTIONS
Jump To

  • Corresponding Author
  • Authors
    • Muhammed Ali Kecebas - Faculty of Engineering and Natural Science, Sabanci University, Istanbul 34956, Turkey
    • Pinar Menguc - Center for Energy, Environment and Economy, Ozyegin University, Istanbul 34794, Turkey
  • Funding

    This material is based upon work supported by the Air Force Office of Scientific Research (Aerospace Materials for Extreme Environments Program, PM: Dr. Ali Sayir) under award number FA8655-22-1-7023.

  • Notes
    The authors declare no competing financial interest.

References

ARTICLE SECTIONS
Jump To

This article references 161 other publications.

  1. 1
    Catalanotti, S.; Cuomo, V.; Piro, G.; Ruggi, D.; Silvestrini, V.; Troise, G. The radiative cooling of selective surfaces. Sol. Energy 1975, 17 (2), 8389,  DOI: 10.1016/0038-092X(75)90062-6
  2. 2
    Raman, A. P.; Anoma, M. A.; Zhu, L.; Rephaeli, E.; Fan, S. Passive radiative cooling below ambient air temperature under direct sunlight. Nature 2014, 515 (7528), 540544,  DOI: 10.1038/nature13883
  3. 3
    Howell, J. R.; Mengüç, M. P.; Daun, K.; Siegel, R. Thermal Radiation Heat Transfer; CRC Press, 2020.
  4. 4
    Idso, S. B.; Jackson, R. D. Thermal radiation from the atmosphere. Journal of geophysical research 1969, 74 (23), 53975403,  DOI: 10.1029/JC074i023p05397
  5. 5
    Zhao, B.; Hu, M.; Ao, X.; Chen, N.; Pei, G. Radiative cooling: A review of fundamentals, materials, applications, and prospects. Applied energy 2019, 236, 489513,  DOI: 10.1016/j.apenergy.2018.12.018
  6. 6
    Li, Z.; Chen, Q.; Song, Y.; Zhu, B.; Zhu, J. Fundamentals, materials, and applications for daytime radiative cooling. Advanced Materials Technologies 2020, 5 (5), 1901007,  DOI: 10.1002/admt.201901007
  7. 7
    Goyal, A. K.; Kumar, A. Recent advances and progresses in photonic devices for passive radiative cooling application: a review. Journal of Nanophotonics 2020, 14 (3), 030901030901,  DOI: 10.1117/1.JNP.14.030901
  8. 8
    Yin, X.; Yang, R.; Tan, G.; Fan, S. Terrestrial radiative cooling: Using the cold universe as a renewable and sustainable energy source. Science 2020, 370 (6518), 786791,  DOI: 10.1126/science.abb0971
  9. 9
    Hossain, M. M.; Gu, M. Radiative cooling: principles, progress, and potentials. Advanced Science 2016, 3 (7), 1500360,  DOI: 10.1002/advs.201500360
  10. 10
    Yu, X.; Chan, J.; Chen, C. Review of radiative cooling materials: Performance evaluation and design approaches. Nano Energy 2021, 88, 106259,  DOI: 10.1016/j.nanoen.2021.106259
  11. 11
    Bijarniya, J. P.; Sarkar, J.; Maiti, P. Review on passive daytime radiative cooling: Fundamentals, recent researches, challenges and opportunities. Renewable and Sustainable Energy Reviews 2020, 133, 110263,  DOI: 10.1016/j.rser.2020.110263
  12. 12
    Zeyghami, M.; Goswami, D. Y.; Stefanakos, E. A review of clear sky radiative cooling developments and applications in renewable power systems and passive building cooling. Sol. Energy Mater. Sol. Cells 2018, 178, 115128,  DOI: 10.1016/j.solmat.2018.01.015
  13. 13
    Sato, D.; Yamada, N. Review of photovoltaic module cooling methods and performance evaluation of the radiative cooling method. Renewable and Sustainable Energy Reviews 2019, 104, 151166,  DOI: 10.1016/j.rser.2018.12.051
  14. 14
    Ahmed, S.; Li, Z.; Javed, M. S.; Ma, T. A review on the integration of radiative cooling and solar energy harvesting. Materials Today Energy 2021, 21, 100776,  DOI: 10.1016/j.mtener.2021.100776
  15. 15
    Chen, J.; Lu, L. Development of radiative cooling and its integration with buildings: A comprehensive review. Sol. Energy 2020, 212, 125151,  DOI: 10.1016/j.solener.2020.10.013
  16. 16
    Lu, X.; Xu, P.; Wang, H.; Yang, T.; Hou, J. Cooling potential and applications prospects of passive radiative cooling in buildings: The current state-of-the-art. Renewable and Sustainable Energy Reviews 2016, 65, 10791097,  DOI: 10.1016/j.rser.2016.07.058
  17. 17
    Li, W.; Li, Y.; Shah, K. W. A materials perspective on radiative cooling structures for buildings. Sol. Energy 2020, 207, 247269,  DOI: 10.1016/j.solener.2020.06.095
  18. 18
    Chen, L.; Zhang, K.; Ma, M.; Tang, S.; Li, F.; Niu, X. Sub-ambient radiative cooling and its application in buildings. Building Simulation 2020, 13, 11651189,  DOI: 10.1007/s12273-020-0646-x
  19. 19
    Pirvaram, A.; Talebzadeh, N.; Leung, S. N.; O’Brien, P. G. Radiative cooling for buildings: A review of techno-enviro-economics and life-cycle assessment methods. Renewable and Sustainable Energy Reviews 2022, 162, 112415,  DOI: 10.1016/j.rser.2022.112415
  20. 20
    Suhendri; Hu, M.; Su, Y.; Darkwa, J.; Riffat, S. Implementation of passive radiative cooling technology in buildings: A review. Buildings 2020, 10 (12), 215,  DOI: 10.3390/buildings10120215
  21. 21
    Hanif, M.; Mahlia, T. M. I.; Zare, A.; Saksahdan, T. J.; Metselaar, H. S. C. Potential energy savings by radiative cooling system for a building in tropical climate. Renewable and sustainable energy reviews 2014, 32, 642650,  DOI: 10.1016/j.rser.2014.01.053
  22. 22
    Zhang, J.; Yuan, J.; Liu, J.; Zhou, Z.; Sui, J.; Xing, J.; Zuo, J. Cover shields for sub-ambient radiative cooling: A literature review. Renewable and Sustainable Energy Reviews 2021, 143, 110959,  DOI: 10.1016/j.rser.2021.110959
  23. 23
    Liu, J.; Zhang, J.; Zhang, D.; Jiao, S.; Xing, J.; Tang, H.; Zhang, Y.; Li, S.; Zhou, Z.; Zuo, J. Sub-ambient radiative cooling with wind cover. Renewable and Sustainable Energy Reviews 2020, 130, 109935,  DOI: 10.1016/j.rser.2020.109935
  24. 24
    Vilà, R.; Martorell, I.; Medrano, M.; Castell, A. Adaptive covers for combined radiative cooling and solar heating. A review of existing technology and materials. Sol. Energy Mater. Sol. Cells 2021, 230, 111275,  DOI: 10.1016/j.solmat.2021.111275
  25. 25
    Wang, J.; Tan, G.; Yang, R.; Zhao, D. Materials, structures, and devices for dynamic radiative cooling. Cell Reports Physical Science 2022, 3, 101198,  DOI: 10.1016/j.xcrp.2022.101198
  26. 26
    An, Y.; Fu, Y.; Dai, J. G.; Yin, X.; Lei, D. Switchable radiative cooling technologies for smart thermal management. Cell Reports Physical Science 2022, 3 (10), 101098,  DOI: 10.1016/j.xcrp.2022.101098
  27. 27
    Taylor, S.; Long, L.; McBurney, R.; Sabbaghi, P.; Chao, J.; Wang, L. Spectrally-selective vanadium dioxide based tunable metafilm emitter for dynamic radiative cooling. Sol. Energy Mater. Sol. Cells 2020, 217, 110739,  DOI: 10.1016/j.solmat.2020.110739
  28. 28
    Xu, X.; Gu, J.; Zhao, H.; Zhang, X.; Dou, S.; Li, Y.; Zhao, J.; Zhan, Y.; Li, X. Passive and dynamic phase-change-based radiative cooling in outdoor weather. ACS Appl. Mater. Interfaces 2022, 14 (12), 1431314320,  DOI: 10.1021/acsami.1c23401
  29. 29
    Wang, S.; Jiang, T.; Meng, Y.; Yang, R.; Tan, G.; Long, Y. Scalable thermochromic smart windows with passive radiative cooling regulation. Science 2021, 374 (6574), 15011504,  DOI: 10.1126/science.abg0291
  30. 30
    Taylor, S.; Yang, Y.; Wang, L. Vanadium dioxide based Fabry-Perot emitter for dynamic radiative cooling applications. Journal of Quantitative Spectroscopy and Radiative Transfer 2017, 197, 7683,  DOI: 10.1016/j.jqsrt.2017.01.014
  31. 31
    Butler, A.; Argyropoulos, C. Mechanically tunable radiative cooling for adaptive thermal control. Applied Thermal Engineering 2022, 211, 118527,  DOI: 10.1016/j.applthermaleng.2022.118527
  32. 32
    Liu, J.; Zhou, Z.; Zhang, J.; Feng, W.; Zuo, J. Advances and challenges in commercializing radiative cooling. Materials Today Physics 2019, 11, 100161,  DOI: 10.1016/j.mtphys.2019.100161
  33. 33
    Cui, Y.; Luo, X.; Zhang, F.; Sun, L.; Jin, N.; Yang, W. Progress of passive daytime radiative cooling technologies towards commercial applications. Particuology 2022, 67, 5767,  DOI: 10.1016/j.partic.2021.10.004
  34. 34
    Jeon, S.; Shin, J. Ideal spectral emissivity for radiative cooling of earthbound objects. Sci. Rep. 2020, 10 (1), 13038,  DOI: 10.1038/s41598-020-70105-y
  35. 35
    Fan, S.; Li, W. Photonics and thermodynamics concepts in radiative cooling. Nat. Photonics 2022, 16 (3), 182190,  DOI: 10.1038/s41566-021-00921-9
  36. 36
    Chen, Z.; Zhu, L.; Raman, A.; Fan, S. Radiative cooling to deep sub-freezing temperatures through a 24-h day-night cycle. Nat. Commun. 2016, 7 (1), 13729,  DOI: 10.1038/ncomms13729
  37. 37
    Chamoli, S. K.; Li, W.; Guo, C.; ElKabbash, M. Angularly selective thermal emitters for deep subfreezing daytime radiative cooling. Nanophotonics 2022, 11 (16), 37093717,  DOI: 10.1515/nanoph-2022-0032
  38. 38
    Lin, S. Y.; Fleming, J. G.; Chow, E.; Bur, J.; Choi, K. K.; Goldberg, A. Enhancement and suppression of thermal emission by a three-dimensional photonic crystal. Phys. Rev. B 2000, 62 (4), R2243,  DOI: 10.1103/PhysRevB.62.R2243
  39. 39
    Schuller, J. A.; Taubner, T.; Brongersma, M. L. Optical antenna thermal emitters. Nat. Photonics 2009, 3 (11), 658661,  DOI: 10.1038/nphoton.2009.188
  40. 40
    Greffet, J. J. Controlled incandescence. Nature 2011, 478 (7368), 191192,  DOI: 10.1038/478191a
  41. 41
    Narayanaswamy, A.; Chen, G. Thermal emission control with one-dimensional metallodielectric photonic crystals. Phys. Rev. B 2004, 70 (12), 125101,  DOI: 10.1103/PhysRevB.70.125101
  42. 42
    Celanovic, I.; Perreault, D.; Kassakian, J. Resonant-cavity enhanced thermal emission. Phys. Rev. B 2005, 72 (7), 075127,  DOI: 10.1103/PhysRevB.72.075127
  43. 43
    Rephaeli, E.; Fan, S. Absorber and emitter for solar thermo-photovoltaic systems to achieve efficiency exceeding the Shockley-Queisser limit. Opt. Express 2009, 17 (17), 1514515159,  DOI: 10.1364/OE.17.015145
  44. 44
    Le Gall, J.; Olivier, M.; Greffet, J. J. Experimental and theoretical study of reflection and coherent thermal emissionby a SiC grating supporting a surface-phonon polariton. Phys. Rev. B 1997, 55 (15), 10105,  DOI: 10.1103/PhysRevB.55.10105
  45. 45
    Luo, C.; Narayanaswamy, A.; Chen, G.; Joannopoulos, J. D. Thermal radiation from photonic crystals: a direct calculation. Phys. Rev. Lett. 2004, 93 (21), 213905,  DOI: 10.1103/PhysRevLett.93.213905
  46. 46
    Chan, D. L.; Soljačić, M.; Joannopoulos, J. D. Thermal emission and design in 2D-periodic metallic photonic crystal slabs. Opt. Express 2006, 14 (19), 87858796,  DOI: 10.1364/OE.14.008785
  47. 47
    Fleming, J. G.; Lin, S. Y.; El-Kady, I.; Biswas, R.; Ho, K. M. All-metallic three-dimensional photonic crystals with a large infrared bandgap. Nature 2002, 417 (6884), 5255,  DOI: 10.1038/417052a
  48. 48
    Rephaeli, E.; Fan, S. Tungsten black absorber for solar light with wide angular operation range. applied physics letters 2008, 92 (21), 211107,  DOI: 10.1063/1.2936997
  49. 49
    Arpin, K. A.; Losego, M. D.; Cloud, A. N.; Ning, H.; Mallek, J.; Sergeant, N. P.; Zhu, L.; Yu, Z.; Kalanyan, B.; Parsons, G. N.; Girolami, G. S.; Abelson, J. R.; Fan, S.; Braun, P. V. Three-dimensional self-assembled photonic crystals with high temperature stability for thermal emission modification. Nat. Commun. 2013, 4 (1), 2630,  DOI: 10.1038/ncomms3630
  50. 50
    Wang, M.; Hu, C.; Pu, M.; Huang, C.; Zhao, Z.; Feng, Q.; Luo, X. Truncated spherical voids for nearly omnidirectional optical absorption. Opt. Express 2011, 19 (21), 2064220649,  DOI: 10.1364/OE.19.020642
  51. 51
    Zhang, S.; Li, Y.; Feng, G.; Zhu, B.; Xiao, S.; Zhou, L.; Zhao, L. Strong infrared absorber: surface-microstructured Au film replicated from black silicon. Opt. Express 2011, 19 (21), 2046220467,  DOI: 10.1364/OE.19.020462
  52. 52
    Kecebas, M. A.; Menguc, M. P.; Kosar, A.; Sendur, K. Passive radiative cooling design with broadband optical thin-film filters. Journal of Quantitative Spectroscopy and Radiative Transfer 2017, 198, 179186,  DOI: 10.1016/j.jqsrt.2017.03.046
  53. 53
    Kecebas, M. A.; Menguc, M. P.; Kosar, A.; Sendur, K. Spectrally selective filter design for passive radiative cooling. JOSA B 2020, 37 (4), 11731182,  DOI: 10.1364/JOSAB.384181
  54. 54
    Kim, M.; Seo, J.; Yoon, S.; Lee, H.; Lee, J.; Lee, B. J. Optimization and performance analysis of a multilayer structure for daytime radiative cooling. Journal of Quantitative Spectroscopy and Radiative Transfer 2021, 260, 107475,  DOI: 10.1016/j.jqsrt.2020.107475
  55. 55
    Shi, Y.; Li, W.; Raman, A.; Fan, S. Optimization of multilayer optical films with a memetic algorithm and mixed integer programming. Acs Photonics 2018, 5 (3), 684691,  DOI: 10.1021/acsphotonics.7b01136
  56. 56
    Guan, Q.; Raza, A.; Mao, S. S.; Vega, L. F.; Zhang, T. Machine Learning-Enabled Inverse Design of Radiative Cooling Film with On-Demand Transmissive Color. ACS Photonics 2023, 10 (3), 715726,  DOI: 10.1021/acsphotonics.2c01857
  57. 57
    Chae, D.; Kim, M.; Jung, P.-H.; Son, S.; Seo, J.; Liu, Y.; Lee, B. J.; Lee, H. Spectrally selective inorganic-based multilayer emitter for daytime radiative cooling. ACS Appl. Mater. Interfaces 2020, 12 (7), 80738081,  DOI: 10.1021/acsami.9b16742
  58. 58
    Ma, H.; Yao, K.; Dou, S.; Xiao, M.; Dai, M.; Wang, L.; Zhao, H.; Zhao, J.; Li, Y.; Zhan, Y. Multilayered SiO2/Si3N4 photonic emitter to achieve high-performance all-day radiative cooling. Sol. Energy Mater. Sol. Cells 2020, 212, 110584,  DOI: 10.1016/j.solmat.2020.110584
  59. 59
    Palik, E. D., Ed.; Handbook of Optical Constants of solids, Vol. 3; Academic Press, 1998.
  60. 60
    Jeong, S. Y.; Tso, C. Y.; Ha, J.; Wong, Y. M.; Chao, C. Y.; Huang, B.; Qiu, H. Field investigation of a photonic multi-layered TiO2 passive radiative cooler in sub-tropical climate. Renewable Energy 2020, 146, 4455,  DOI: 10.1016/j.renene.2019.06.119
  61. 61
    Lee, G. J.; Kim, Y. J.; Kim, H. M.; Yoo, Y. J.; Song, Y. M. Colored, daytime radiative coolers with thin-film resonators for aesthetic purposes. Advanced Optical Materials 2018, 6 (22), 1800707,  DOI: 10.1002/adom.201800707
  62. 62
    Tikhonravov, A. V.; Trubetskov, M. K.; DeBell, G. W. Application of the needle optimization technique to the design of optical coatings. Applied optics 1996, 35 (28), 54935508,  DOI: 10.1364/AO.35.005493
  63. 63
    Vincent, P.; Cunha Sergio, G.; Jang, J.; Kang, I. M.; Park, J.; Kim, H.; Lee, M.; Bae, J.-H. Application of genetic algorithm for more efficient multi-layer thickness optimization in solar cells. Energies 2020, 13 (7), 1726,  DOI: 10.3390/en13071726
  64. 64
    Kou, J. L.; Jurado, Z.; Chen, Z.; Fan, S.; Minnich, A. J. Daytime radiative cooling using near-black infrared emitters. Acs Photonics 2017, 4 (3), 626630,  DOI: 10.1021/acsphotonics.6b00991
  65. 65
    Chae, D.; Lim, H.; So, S.; Son, S.; Ju, S.; Kim, W.; Rho, J.; Lee, H. Spectrally selective nanoparticle mixture coating for passive daytime radiative cooling. ACS Appl. Mater. Interfaces 2021, 13 (18), 2111921126,  DOI: 10.1021/acsami.0c20311
  66. 66
    Gangisetty, G.; Zevenhoven, R. A Review of Nanoparticle Material Coatings in Passive Radiative Cooling Systems Including Skylights. Energies 2023, 16 (4), 1975,  DOI: 10.3390/en16041975
  67. 67
    Cheng, Z.; Shuai, Y.; Gong, D.; Wang, F.; Liang, H.; Li, G. Optical properties and cooling performance analyses of single-layer radiative cooling coating with mixture of TiO2 particles and SiO2 particles. Science China Technological Sciences 2021, 64 (5), 10171029,  DOI: 10.1007/s11431-020-1586-9
  68. 68
    Huang, Z.; Ruan, X. Nanoparticle embedded double-layer coating for daytime radiative cooling. International journal of heat and mass transfer 2017, 104, 890896,  DOI: 10.1016/j.ijheatmasstransfer.2016.08.009
  69. 69
    Cheng, Z.; Wang, F.; Wang, H.; Liang, H.; Ma, L. Effect of embedded polydisperse glass microspheres on radiative cooling of a coating. International Journal of Thermal Sciences 2019, 140, 358367,  DOI: 10.1016/j.ijthermalsci.2019.03.014
  70. 70
    Bao, H.; Yan, C.; Wang, B.; Fang, X.; Zhao, C. Y.; Ruan, X. Double-layer nanoparticle-based coatings for efficient terrestrial radiative cooling. Sol. Energy Mater. Sol. Cells 2017, 168, 7884,  DOI: 10.1016/j.solmat.2017.04.020
  71. 71
    Huang, J.; Li, M.; Fan, D. Core-shell particles for devising high-performance full-day radiative cooling paint. Applied Materials Today 2021, 25, 101209,  DOI: 10.1016/j.apmt.2021.101209
  72. 72
    Hu, D.; Sun, S.; Du, P.; Lu, X.; Zhang, H.; Zhang, Z. Hollow core-shell particle-containing coating for passive daytime radiative cooling. Composites Part A: Applied Science and Manufacturing 2022, 158, 106949,  DOI: 10.1016/j.compositesa.2022.106949
  73. 73
    Zhai, Y.; Ma, Y.; David, S. N.; Zhao, D.; Lou, R.; Tan, G.; Yang, R.; Yin, X. Scalable-manufactured randomized glass-polymer hybrid metamaterial for daytime radiative cooling. Science 2017, 355 (6329), 10621066,  DOI: 10.1126/science.aai7899
  74. 74
    Ko, B.; Lee, D.; Badloe, T.; Rho, J. Metamaterial-based radiative cooling: towards energy-free all-day cooling. Energies 2019, 12 (1), 89,  DOI: 10.3390/en12010089
  75. 75
    Kravets, V. G.; Kabashin, A. V.; Barnes, W. L.; Grigorenko, A. N. Plasmonic surface lattice resonances: a review of properties and applications. Chem. Rev. 2018, 118 (12), 59125951,  DOI: 10.1021/acs.chemrev.8b00243
  76. 76
    Atwater, H. A.; Polman, A. Plasmonics for improved photovoltaic devices. Nature materials 2010, 9 (3), 205213,  DOI: 10.1038/nmat2629
  77. 77
    Utyushev, A. D.; Zakomirnyi, V. I.; Rasskazov, I. L. Collective lattice resonances: Plasmonics and beyond. Reviews in Physics 2021, 6, 100051,  DOI: 10.1016/j.revip.2021.100051
  78. 78
    Amendola, V.; Pilot, R.; Frasconi, M.; Maragò, O. M.; Iatì, M. A. Surface plasmon resonance in gold nanoparticles: a review. J. Phys.: Condens. Matter 2017, 29 (20), 203002,  DOI: 10.1088/1361-648X/aa60f3
  79. 79
    Cherqui, C.; Bourgeois, M. R.; Wang, D.; Schatz, G. C. Plasmonic surface lattice resonances: Theory and computation. Accounts of chemical research 2019, 52 (9), 25482558,  DOI: 10.1021/acs.accounts.9b00312
  80. 80
    Rodriguez, S. R. K.; Abass, A.; Maes, B.; Janssen, O. T. A.; Vecchi, G.; Gomez Rivas, J. Coupling bright and dark plasmonic lattice resonances. Physical Review X 2011, 1 (2), 021019,  DOI: 10.1103/PhysRevX.1.021019
  81. 81
    Humphrey, A. D.; Barnes, W. L. Plasmonic surface lattice resonances on arrays of different lattice symmetry. Phys. Rev. B 2014, 90 (7), 075404,  DOI: 10.1103/PhysRevB.90.075404
  82. 82
    Rephaeli, E.; Raman, A.; Fan, S. Ultrabroadband photonic structures to achieve high-performance daytime radiative cooling. Nano Lett. 2013, 13 (4), 14571461,  DOI: 10.1021/nl4004283
  83. 83
    Choi, M.; Seo, J.; Yoon, S.; Nam, Y.; Lee, J.; Lee, B. J. All-day radiative cooling using a grating-patterned PDMS film emitter. Applied Thermal Engineering 2022, 214, 118771,  DOI: 10.1016/j.applthermaleng.2022.118771
  84. 84
    Seo, J.; Choi, M.; Lee, J.; Lee, B. J. Optimization of a grating structure in hexagonal array with omnidirectional emission for daytime radiative cooling. Journal of Quantitative Spectroscopy and Radiative Transfer 2022, 284, 108165,  DOI: 10.1016/j.jqsrt.2022.108165
  85. 85
    Wong, R. Y.; Tso, C. Y.; Chao, C. Y.; Huang, B.; Wan, M. P. Ultra-broadband asymmetric transmission metallic gratings for subtropical passive daytime radiative cooling. Sol. Energy Mater. Sol. Cells 2018, 186, 330339,  DOI: 10.1016/j.solmat.2018.07.002
  86. 86
    Long, L.; Yang, Y.; Wang, L. Simultaneously enhanced solar absorption and radiative cooling with thin silica micro-grating coatings for silicon solar cells. Sol. Energy Mater. Sol. Cells 2019, 197, 1924,  DOI: 10.1016/j.solmat.2019.04.006
  87. 87
    Dai, Y.; Zhang, Z.; Ma, C. Radiative cooling with multilayered periodic grating under sunlight. Opt. Commun. 2020, 475, 126231,  DOI: 10.1016/j.optcom.2020.126231
  88. 88
    Hervé, A.; Drévillon, J.; Ezzahri, Y.; Joulain, K. Radiative cooling by tailoring surfaces with microstructures: Association of a grating and a multi-layer structure. Journal of Quantitative Spectroscopy and Radiative Transfer 2018, 221, 155163,  DOI: 10.1016/j.jqsrt.2018.09.015
  89. 89
    Hossain, M. M.; Jia, B.; Gu, M. A metamaterial emitter for highly efficient radiative cooling. Adv. Opt. Mater. 2015, 3 (8), 10471051,  DOI: 10.1002/adom.201500119
  90. 90
    Cui, Y.; He, Y.; Jin, Y.; Ding, F.; Yang, L.; Ye, Y.; Zhong, S.; Lin, Y.; He, S. Plasmonic and metamaterial structures as electromagnetic absorbers. Laser & Photonics Reviews 2014, 8 (4), 495520,  DOI: 10.1002/lpor.201400026
  91. 91
    Perrakis, G.; Tasolamprou, A. C.; Kenanakis, G.; Economou, E. N.; Tzortzakis, S.; Kafesaki, M. Combined nano and micro structuring for enhanced radiative cooling and efficiency of photovoltaic cells. Sci. Rep. 2021, 11 (1), 11552,  DOI: 10.1038/s41598-021-91061-1
  92. 92
    Zhao, B.; Lu, K.; Hu, M.; Liu, J.; Wu, L.; Xu, C.; Xuan, Q.; Pei, G. Radiative cooling of solar cells with micro-grating photonic cooler. Renewable Energy 2022, 191, 662668,  DOI: 10.1016/j.renene.2022.04.063
  93. 93
    Zhu, L.; Raman, A.; Wang, K. X.; Anoma, M. A.; Fan, S. Radiative cooling of solar cells. Optica 2014, 1 (1), 3238,  DOI: 10.1364/OPTICA.1.000032
  94. 94
    Zhao, B.; Hu, M.; Ao, X.; Pei, G. Performance analysis of enhanced radiative cooling of solar cells based on a commercial silicon photovoltaic module. Sol. Energy 2018, 176, 248255,  DOI: 10.1016/j.solener.2018.10.043
  95. 95
    Gentle, A. R.; Smith, G. B. Is enhanced radiative cooling of solar cell modules worth pursuing?. Sol. Energy Mater. Sol. Cells 2016, 150, 3942,  DOI: 10.1016/j.solmat.2016.01.039
  96. 96
    Yalcin, R. A.; Blandre, E.; Joulain, K.; Drévillon, J. Colored radiative cooling coatings with nanoparticles. ACS photonics 2020, 7 (5), 13121322,  DOI: 10.1021/acsphotonics.0c00513
  97. 97
    Xi, W.; Liu, Y.; Zhao, W.; Hu, R.; Luo, X. Colored radiative cooling: How to balance color display and radiative cooling performance. International Journal of Thermal Sciences 2021, 170, 107172,  DOI: 10.1016/j.ijthermalsci.2021.107172
  98. 98
    Kim, H. H.; Im, E.; Lee, S. Colloidal photonic assemblies for colorful radiative cooling. Langmuir 2020, 36 (23), 65896596,  DOI: 10.1021/acs.langmuir.0c00051
  99. 99
    Zhou, L.; Rada, J.; Song, H.; Ooi, B.; Yu, Z.; Gan, Q. Colorful surfaces for radiative cooling. Journal of Photonics for Energy 2021, 11 (4), 042107042107,  DOI: 10.1117/1.JPE.11.042107
  100. 100
    Son, S.; Jeon, S.; Chae, D.; Lee, S. Y.; Liu, Y.; Lim, H.; Oh, S. J.; Lee, H. Colored emitters with silica-embedded perovskite nanocrystals for efficient daytime radiative cooling. Nano Energy 2021, 79, 105461,  DOI: 10.1016/j.nanoen.2020.105461
  101. 101
    Zhu, W.; Droguet, B.; Shen, Q.; Zhang, Y.; Parton, T. G.; Shan, X.; Parker, R. M.; De Volder, M. F. L.; Deng, T.; Vignolini, S.; Li, T. Structurally colored radiative cooling cellulosic films. Advanced Science 2022, 9 (26), 2202061,  DOI: 10.1002/advs.202202061
  102. 102
    Blandre, E.; Yalcin, R. A.; Joulain, K.; Drévillon, J. Microstructured surfaces for colored and non-colored sky radiative cooling. Opt. Express 2020, 28 (20), 2970329713,  DOI: 10.1364/OE.401368
  103. 103
    Ding, Z.; Li, X.; Fan, X.; Xu, M.; Zhao, J.; Li, Y.; Xu, H. A review of the development of colored radiative cooling surfaces. Carbon Capture Science & Technology 2022, 4, 100066,  DOI: 10.1016/j.ccst.2022.100066
  104. 104
    Zhai, H.; Fan, D.; Li, Q. Scalable and paint-format colored coatings for passive radiative cooling. Sol. Energy Mater. Sol. Cells 2022, 245, 111853,  DOI: 10.1016/j.solmat.2022.111853
  105. 105
    Yalcin, R. A.; Blandre, E.; Joulain, K.; Drévillon, J. Colored radiative cooling coatings with fluorescence. Journal of Photonics for Energy 2021, 11 (3), 032104032104,  DOI: 10.1117/1.JPE.11.032104
  106. 106
    Min, S.; Jeon, S.; Yun, K.; Shin, J. All-color sub-ambient radiative cooling based on photoluminescence. ACS Photonics 2022, 9 (4), 11961205,  DOI: 10.1021/acsphotonics.1c01648
  107. 107
    Sheng, C.; An, Y.; Du, J.; Li, X. Colored radiative cooler under optical Tamm resonance. ACS Photonics 2019, 6 (10), 25452552,  DOI: 10.1021/acsphotonics.9b01005
  108. 108
    Lee, G. J.; Kim, Y. J.; Kim, H. M.; Yoo, Y. J.; Song, Y. M. Colored, daytime radiative coolers with thin-film resonators for aesthetic purposes. Advanced Optical Materials 2018, 6 (22), 1800707,  DOI: 10.1002/adom.201800707
  109. 109
    Mandal, J.; Fu, Y.; Overvig, A. C.; Jia, M.; Sun, K.; Shi, N. N.; Zhou, H.; Xiao, X.; Yu, N.; Yang, Y. Hierarchically porous polymer coatings for highly efficient passive daytime radiative cooling. Science 2018, 362 (6412), 315319,  DOI: 10.1126/science.aat9513
  110. 110
    Xiang, B.; Zhang, R.; Luo, Y.; Zhang, S.; Xu, L.; Min, H.; Tang, S.; Meng, X. 3D porous polymer film with designed pore architecture and auto-deposited SiO2 for highly efficient passive radiative cooling. Nano Energy 2021, 81, 105600,  DOI: 10.1016/j.nanoen.2020.105600
  111. 111
    Son, S.; Liu, Y.; Chae, D.; Lee, H. Cross-linked porous polymeric coating without a metal-reflective layer for sub-ambient radiative cooling. ACS Appl. Mater. Interfaces 2020, 12 (52), 5783257839,  DOI: 10.1021/acsami.0c14792
  112. 112
    Liu, J.; Tang, H.; Jiang, C.; Wu, S.; Ye, L.; Zhao, D.; Zhou, Z. Micro-Nano Porous Structure for Efficient Daytime Radiative Sky Cooling. Adv. Funct. Mater. 2022, 32 (44), 2206962,  DOI: 10.1002/adfm.202206962
  113. 113
    Chen, M.; Pang, D.; Mandal, J.; Chen, X.; Yan, H.; He, Y.; Yu, N.; Yang, Y. Designing mesoporous photonic structures for high-performance passive daytime radiative cooling. Nano Lett. 2021, 21 (3), 14121418,  DOI: 10.1021/acs.nanolett.0c04241
  114. 114
    Sun, J.; Wang, J.; Guo, T.; Bao, H.; Bai, S. Daytime passive radiative cooling materials based on disordered media: A review. Sol. Energy Mater. Sol. Cells 2022, 236, 111492,  DOI: 10.1016/j.solmat.2021.111492
  115. 115
    Li, D.; Liu, X.; Li, W.; Lin, Z.; Zhu, B.; Li, Z.; Li, J.; Li, B.; Fan, S.; Xie, J.; Zhu, J. Scalable and hierarchically designed polymer film as a selective thermal emitter for high-performance all-day radiative cooling. Nat. Nanotechnol. 2021, 16 (2), 153158,  DOI: 10.1038/s41565-020-00800-4
  116. 116
    Wang, T.; Wu, Y.; Shi, L.; Hu, X.; Chen, M.; Wu, L. A structural polymer for highly efficient all-day passive radiative cooling. Nat. Commun. 2021, 12 (1), 365,  DOI: 10.1038/s41467-020-20646-7
  117. 117
    Mandal, J.; Yang, Y.; Yu, N.; Raman, A. P. Paints as a scalable and effective radiative cooling technology for buildings. Joule 2020, 4 (7), 13501356,  DOI: 10.1016/j.joule.2020.04.010
  118. 118
    Family, R.; Mengüç, M. P. Materials for radiative cooling: a review. Procedia environmental sciences 2017, 38, 752759,  DOI: 10.1016/j.proenv.2017.03.158
  119. 119
    Eriksson, T. S.; Lushiku, E. M.; Granqvist, C. G. Materials for radiative cooling to low temperature. Solar energy materials 1984, 11 (3), 149161,  DOI: 10.1016/0165-1633(84)90067-4
  120. 120
    Pirouzfam, N.; Menguc, M. P.; Sendur, K. Colorization of passive radiative cooling coatings using plasmonic effects. Sol. Energy Mater. Sol. Cells 2023, 253, 112225,  DOI: 10.1016/j.solmat.2023.112225
  121. 121
    Dou, S.; Xu, H.; Zhao, J.; Zhang, K.; Li, N.; Lin, Y.; Pan, L.; Li, Y. Bioinspired microstructured materials for optical and thermal regulation. Adv. Mater. 2021, 33 (6), 2000697,  DOI: 10.1002/adma.202000697
  122. 122
    Fu, S. C.; Zhong, X. L.; Zhang, Y.; Lai, T. W.; Chan, K. C.; Lee, K. Y.; Chao, C. Y. Bio-inspired cooling technologies and the applications in buildings. Energy and Buildings 2020, 225, 110313,  DOI: 10.1016/j.enbuild.2020.110313
  123. 123
    Shi, N. N. Biological and Bioinspired Photonic Materials for Passive Radiative Cooling and Waveguiding . Ph.D. Thesis, Columbia University, 2018.
  124. 124
    Yang, J.; Zhang, X.; Zhang, X.; Wang, L.; Feng, W.; Li, Q. Beyond the visible: bioinspired infrared adaptive materials. Adv. Mater. 2021, 33 (14), 2004754,  DOI: 10.1002/adma.202004754
  125. 125
    Shi, N. N.; Tsai, C. C.; Camino, F.; Bernard, G. D.; Yu, N.; Wehner, R. Keeping cool: Enhanced optical reflection and radiative heat dissipation in Saharan silver ants. Science 2015, 349 (6245), 298301,  DOI: 10.1126/science.aab3564
  126. 126
    Shi, N. N.; Tsai, C. C.; Camino, F.; Bernard, G. D.; Wehner, R.; Yu, N. Radiative cooling nano-photonic structures discovered in saharan silver ants and related biomimetic metasurfaces. In CLEO: QELS_Fundamental Science , San Jose, California, June 2016.  DOI: 10.1364/CLEO_QELS.2016.FTh3B.1 .
  127. 127
    Jeong, S. Y.; Tso, C. Y.; Wong, Y. M.; Chao, C. Y. FDTD simulations inspired by the daytime passive radiative cooling of the Sahara silver ant. In Proceedings of 4th International Conference on Building Energy and Environment , Melbourne, Australia, February 2018.
  128. 128
    Wu, W.; Lin, S.; Wei, M.; Huang, J.; Xu, H.; Lu, Y.; Song, W. Flexible passive radiative cooling inspired by Saharan silver ants. Sol. Energy Mater. Sol. Cells 2020, 210, 110512,  DOI: 10.1016/j.solmat.2020.110512
  129. 129
    Lin, S.; Ai, L.; Zhang, J.; Bu, T.; Li, H.; Huang, F.; Zhang, J.; Lu, Y.; Song, W. Silver ants-inspired flexible photonic architectures with improved transparency and heat radiation for photovoltaic devices. Sol. Energy Mater. Sol. Cells 2019, 203, 110135,  DOI: 10.1016/j.solmat.2019.110135
  130. 130
    Li, T.; Zhai, Y.; He, S.; Gan, W.; Wei, Z.; Heidarinejad, M.; Dalgo, D.; Mi, R.; Zhao, X.; Song, J.; Dai, J.; Chen, C.; Aili, A.; Vellore, A.; Martini, A.; Yang, R.; Srebric, J.; Yin, X.; Hu, L. A radiative cooling structural material. Science 2019, 364 (6442), 760763,  DOI: 10.1126/science.aau9101
  131. 131
    Chowdhury, F. I.; Xu, Q.; Sinha, K.; Wang, X. Cellulose-upgraded polymer films for radiative sky cooling. Journal of Quantitative Spectroscopy and Radiative Transfer 2021, 272, 107824,  DOI: 10.1016/j.jqsrt.2021.107824
  132. 132
    Gamage, S.; Banerjee, D.; Alam, M. M.; Hallberg, T.; Akerlind, C.; Sultana, A.; Shanker, R.; Berggren, M.; Crispin, X.; Kariis, H.; Zhao, D.; Jonsson, M. P. Reflective and transparent cellulose-based passive radiative coolers. Cellulose 2021, 28 (14), 93839393,  DOI: 10.1007/s10570-021-04112-1
  133. 133
    Chen, X.; He, M.; Feng, S.; Xu, Z.; Peng, H.; Shi, S.; Liu, C.; Zhou, Y. Cellulose-based porous polymer film with auto-deposited TiO2 as spectrally selective materials for passive daytime radiative cooling. Opt. Mater. 2021, 120, 111431,  DOI: 10.1016/j.optmat.2021.111431
  134. 134
    Jaramillo-Fernandez, J.; Yang, H.; Schertel, L.; Whitworth, G. L.; Garcia, P. D.; Vignolini, S.; Sotomayor-Torres, C. M. Highly-scattering cellulose-based films for radiative cooling. Advanced Science 2022, 9 (8), 2104758,  DOI: 10.1002/advs.202104758
  135. 135
    Chen, Y.; Dang, B.; Fu, J.; Wang, C.; Li, C.; Sun, Q.; Li, H. Cellulose-based hybrid structural material for radiative cooling. Nano Lett. 2021, 21 (1), 397404,  DOI: 10.1021/acs.nanolett.0c03738
  136. 136
    Tian, Y.; Shao, H.; Liu, X.; Chen, F.; Li, Y.; Tang, C.; Zheng, Y. Superhydrophobic and recyclable cellulose-fiber-based composites for high-efficiency passive radiative cooling. ACS Appl. Mater. Interfaces 2021, 13 (19), 2252122530,  DOI: 10.1021/acsami.1c04046
  137. 137
    Cheng, Z.; Han, H.; Wang, F.; Yan, Y.; Shi, X.; Liang, H.; Zhang, X.; Shuai, Y. Efficient radiative cooling coating with biomimetic human skin wrinkle structure. Nano Energy 2021, 89, 106377,  DOI: 10.1016/j.nanoen.2021.106377
  138. 138
    Lauster, T.; Mauel, A.; Herrmann, K.; Veitengruber, V.; Song, Q.; Senker, J.; Retsch, M. From Chitosan to Chitin: Bio-Inspired Thin Films for Passive Daytime Radiative Cooling. Advanced Science 2023, 10, 2206616,  DOI: 10.1002/advs.202206616
  139. 139
    Liu, B.-Y.; Xue, C.-H.; Zhong, H.-M.; Guo, X.-J.; Wang, H.-D.; Li, H.-G.; Du, M.-M.; Huang, M.-C.; Wei, R.-X.; Song, L.-G.; Chang, B.; Wang, Z. Multi-bioinspired self-cleaning energy-free cooling coatings. Journal of Materials Chemistry A 2021, 9 (43), 2427624282,  DOI: 10.1039/D1TA07953K
  140. 140
    Yang, Z.; Sun, H.; Xi, Y.; Qi, Y.; Mao, Z.; Wang, P.; Zhang, J. Bio-inspired structure using random, three-dimensional pores in the polymeric matrix for daytime radiative cooling. Sol. Energy Mater. Sol. Cells 2021, 227, 111101,  DOI: 10.1016/j.solmat.2021.111101
  141. 141
    Wang, S.; Wang, Y.; Zou, Y.; Chen, G.; Ouyang, J.; Jia, D.; Zhou, Y. Biologically inspired scalable-manufactured dual-layer coating with a hierarchical micropattern for highly efficient passive radiative cooling and robust superhydrophobicity. ACS Appl. Mater. Interfaces 2021, 13 (18), 2188821897,  DOI: 10.1021/acsami.1c05651
  142. 142
    Jeong, S. Y.; Tso, C. Y.; Wong, Y. M.; Chao, C. Y.; Huang, B. Daytime passive radiative cooling by ultra emissive bio-inspired polymeric surface. Sol. Energy Mater. Sol. Cells 2020, 206, 110296,  DOI: 10.1016/j.solmat.2019.110296
  143. 143
    Yang, Z.; Zhang, J. Bioinspired radiative cooling structure with randomly stacked fibers for efficient all-day passive cooling. ACS Appl. Mater. Interfaces 2021, 13 (36), 4338743395,  DOI: 10.1021/acsami.1c12267
  144. 144
    Yang, M.; Zou, W.; Guo, J.; Qian, Z.; Luo, H.; Yang, S.; Zhao, N.; Pattelli, L.; Xu, J.; Wiersma, D. S. Bioinspired “skin” with cooperative thermo-optical effect for daytime radiative cooling. ACS Appl. Mater. Interfaces 2020, 12 (22), 2528625293,  DOI: 10.1021/acsami.0c03897
  145. 145
    Zhang, H.; Ly, K. C. S.; Liu, X.; Chen, Z.; Yan, M.; Wu, Z.; Wang, X.; Zheng, Y.; Zhou, H.; Fan, T. Biologically inspired flexible photonic films for efficient passive radiative cooling. Proc. Natl. Acad. Sci. U. S. A. 2020, 117 (26), 1465714666,  DOI: 10.1073/pnas.2001802117
  146. 146
    Didari, A.; Mengüç, M. P. A biomimicry design for nanoscale radiative cooling applications inspired by Morpho didius butterfly. Sci. Rep. 2018, 8 (1), 16891,  DOI: 10.1038/s41598-018-35082-3
  147. 147
    Didari-Bader, A.; Pinar Mengüç, M. Near-field radiative transfer for biologically inspired structures. In Light, Plasmonics and Particles; Pinar Mengüç, M., Francoeur, M., Eds.; Elsevier, May 2023; Chapter 22.
  148. 148
    Choi, S. H.; Kim, S.-W.; Ku, Z.; Visbal-Onufrak, M. A.; Kim, S.-R.; Choi, K.-H.; Ko, H.; Choi, W.; Urbas, A. M.; Goo, T.-W.; Kim, Y. L. Anderson light localization in biological nanostructures of native silk. Nat. Commun. 2018, 9 (1), 452,  DOI: 10.1038/s41467-017-02500-5
  149. 149
    Hsu, P.-C.; Song, A. Y.; Catrysse, P. B.; Liu, C.; Peng, Y.; Xie, J.; Fan, S.; Cui, Y. Radiative human body cooling by nanoporous polyethylene textile. Science 2016, 353 (6303), 10191023,  DOI: 10.1126/science.aaf5471
  150. 150
    Tong, J. K.; Huang, X.; Boriskina, S. V.; Loomis, J.; Xu, Y.; Chen, G. Infrared-transparent visible-opaque fabrics for wearable personal thermal management. Acs Photonics 2015, 2 (6), 769778,  DOI: 10.1021/acsphotonics.5b00140
  151. 151
    Catrysse, P. B.; Song, A. Y.; Fan, S. Photonic structure textile design for localized thermal cooling based on a fiber blending scheme. ACS Photonics 2016, 3 (12), 24202426,  DOI: 10.1021/acsphotonics.6b00644
  152. 152
    Hsu, P.-C.; Liu, C.; Song, A. Y.; Zhang, Z.; Peng, Y.; Xie, J.; Liu, K.; Wu, C.-L.; Catrysse, P. B.; Cai, L.; Zhai, S.; Majumdar, A.; Fan, S.; Cui, Y. A dual-mode textile for human body radiative heating and cooling. Science Advances 2017, 3 (11), e1700895  DOI: 10.1126/sciadv.1700895
  153. 153
    Peng, Y.; Chen, J.; Song, A. Y.; Catrysse, P. B.; Hsu, P.-C.; Cai, L.; Liu, B.; Zhu, Y.; Zhou, G.; Wu, D. S.; Lee, H. R.; Fan, S.; Cui, Y. Nanoporous polyethylene microfibres for large-scale radiative cooling fabric. Nature Sustainability 2018, 1 (2), 105112,  DOI: 10.1038/s41893-018-0023-2
  154. 154
    Hsu, P. C.; Li, X. Photon-engineered radiative cooling textiles. Science 2020, 370 (6518), 784785,  DOI: 10.1126/science.abe4476
  155. 155
    Cai, L.; Song, A. Y.; Li, W.; Hsu, P.-C.; Lin, D.; Catrysse, P. B.; Liu, Y.; Peng, Y.; Chen, J.; Wang, H.; Xu, J.; Yang, A.; Fan, S.; Cui, Y. Spectrally selective nanocomposite textile for outdoor personal cooling. Adv. Mater. 2018, 30 (35), 1802152,  DOI: 10.1002/adma.201802152
  156. 156
    Peng, Y.; Cui, Y. Advanced textiles for personal thermal management and energy. Joule 2020, 4 (4), 724742,  DOI: 10.1016/j.joule.2020.02.011
  157. 157
    Luo, H.; Li, Q.; Du, K.; Xu, Z.; Zhu, H.; Liu, D.; Cai, L.; Ghosh, P.; Qiu, M. An ultra-thin colored textile with simultaneous solar and passive heating abilities. Nano Energy 2019, 65, 103998,  DOI: 10.1016/j.nanoen.2019.103998
  158. 158
    Luo, H.; Zhu, Y.; Xu, Z.; Hong, Y.; Ghosh, P.; Kaur, S.; Wu, M.; Yang, C.; Qiu, M.; Li, Q. Outdoor personal thermal management with simultaneous electricity generation. Nano Lett. 2021, 21 (9), 38793886,  DOI: 10.1021/acs.nanolett.1c00400
  159. 159
    Byers, H. R.; Landsberg, H. E.; Wexler, H.; Haurwitz, B.; Spilhaus, A. F.; Willett, H. C.; Buettner, K. J. Physical Aspects of Human Bioclimatology. In Compendium of Meteorology; Committee on the Compendium of Meteorology, 1951; pp 11121125.
  160. 160
    Palik, E. D., Ed.; Handbook of Optical Constants of Solids, Vol. 3; Academic Press, 1998.
  161. 161
    Siefke, T.; Kroker, S.; Pfeiffer, K.; Puffky, O.; Dietrich, K.; Franta, D.; Ohlidal, I.; Szeghalmi, A.; Kley, E.-B.; Tunnermann, A. Materials pushing the application limits of wire grid polarizers further into the deep ultraviolet spectral range. Advanced Optical Materials 2016, 4 (11), 17801786,  DOI: 10.1002/adom.201600250

Cited By

ARTICLE SECTIONS
Jump To

This article has not yet been cited by other publications.

  • Abstract

    Figure 1

    Figure 1. (a) Solar irradiance (red), transmission of the atmosphere (blue), and atmospheric thermal radiation at TAmb = 300 K (green). (b) Blackbody radiation from a surface at increasing temperatures, Ts = 280,300 and 320 K at 5–25 μm spectrum interval.

    Figure 2

    Figure 2. (a) Selective emission, ε(λ) = 1 when 8 < λ < 13 μm and ε(λ) = 0 elsewhere, and broadband emission, ε(λ) = 1 when λ > 8 μm and ε(λ) = 0 λ < 8 μm profiles. (b) Corresponding TsPCool(Ts) curves for the selective and broadband emission profiles.

    Figure 3

    Figure 3. (a) Schematic representation of a thermally closed system.(b) Comparison of selective, broadband, and narrowband emissivity profiles. (c) Corresponding TsPCool profiles for selective, broadband, and narrowband emissivity profiles with TEq points marked. (d) Change of TEq with increasing q for selective, broadband, and narrowband emissivity profiles.

    Figure 4

    Figure 4. TEq with respect to increasing q: (a) at fixed hc = 0 and increasing TAmb with transition points PCrit (green) from selective profile (blue) to broadband profile (red) and (b) at fixed TAmb = 297 K and increasing hc with transition points PCrit (black) from selective profile (green) to broadband profile (purple).

    Figure 5

    Figure 5. Comparison of selective and different broadband profiles with varying unity emission starting points. (b) Change of TEq with increasing q for selective and different broadband profiles.

    Figure 6

    Figure 6. (a) Calculated spectra for the structures: (I) SiO2–TiO2 pair designed for TEq minimization and CP maximization. (II) SiO2–Al2O3 pair designed for TEq minimization and CP maximization. (III) SiO2–TiO2 pairs designed for TEq minimization and CP maximization for hc = 5 Wm2– K–1 and q = 400 Wm2–. (b) TsPCool curves for the structures designed to minimize TEq and selective profile. (c) TsPCool curves for the structures designed to maximize PCool and broadband profile. (d) TsPCool curves for the structure with SiO2–TiO2 pair designed to minimize TEq and maximize CP.

    Figure 7

    Figure 7. (a) Real parts of the refractive indices of TiO2 and Al2O3. (b) Imaginary parts of the refractive indices of TiO2 and Al2O3. (c) Reflection of single TiO2 medium. (d) Reflection of single Al2O3 medium. (e) Reflection coefficients of TiO2 on complex reflection plane. (f) Reflection coefficients of Al2O3 on complex reflection plane.

  • References

    ARTICLE SECTIONS
    Jump To

    This article references 161 other publications.

    1. 1
      Catalanotti, S.; Cuomo, V.; Piro, G.; Ruggi, D.; Silvestrini, V.; Troise, G. The radiative cooling of selective surfaces. Sol. Energy 1975, 17 (2), 8389,  DOI: 10.1016/0038-092X(75)90062-6
    2. 2
      Raman, A. P.; Anoma, M. A.; Zhu, L.; Rephaeli, E.; Fan, S. Passive radiative cooling below ambient air temperature under direct sunlight. Nature 2014, 515 (7528), 540544,  DOI: 10.1038/nature13883
    3. 3
      Howell, J. R.; Mengüç, M. P.; Daun, K.; Siegel, R. Thermal Radiation Heat Transfer; CRC Press, 2020.
    4. 4
      Idso, S. B.; Jackson, R. D. Thermal radiation from the atmosphere. Journal of geophysical research 1969, 74 (23), 53975403,  DOI: 10.1029/JC074i023p05397
    5. 5
      Zhao, B.; Hu, M.; Ao, X.; Chen, N.; Pei, G. Radiative cooling: A review of fundamentals, materials, applications, and prospects. Applied energy 2019, 236, 489513,  DOI: 10.1016/j.apenergy.2018.12.018
    6. 6
      Li, Z.; Chen, Q.; Song, Y.; Zhu, B.; Zhu, J. Fundamentals, materials, and applications for daytime radiative cooling. Advanced Materials Technologies 2020, 5 (5), 1901007,  DOI: 10.1002/admt.201901007
    7. 7
      Goyal, A. K.; Kumar, A. Recent advances and progresses in photonic devices for passive radiative cooling application: a review. Journal of Nanophotonics 2020, 14 (3), 030901030901,  DOI: 10.1117/1.JNP.14.030901
    8. 8
      Yin, X.; Yang, R.; Tan, G.; Fan, S. Terrestrial radiative cooling: Using the cold universe as a renewable and sustainable energy source. Science 2020, 370 (6518), 786791,  DOI: 10.1126/science.abb0971
    9. 9
      Hossain, M. M.; Gu, M. Radiative cooling: principles, progress, and potentials. Advanced Science 2016, 3 (7), 1500360,  DOI: 10.1002/advs.201500360
    10. 10
      Yu, X.; Chan, J.; Chen, C. Review of radiative cooling materials: Performance evaluation and design approaches. Nano Energy 2021, 88, 106259,  DOI: 10.1016/j.nanoen.2021.106259
    11. 11
      Bijarniya, J. P.; Sarkar, J.; Maiti, P. Review on passive daytime radiative cooling: Fundamentals, recent researches, challenges and opportunities. Renewable and Sustainable Energy Reviews 2020, 133, 110263,  DOI: 10.1016/j.rser.2020.110263
    12. 12
      Zeyghami, M.; Goswami, D. Y.; Stefanakos, E. A review of clear sky radiative cooling developments and applications in renewable power systems and passive building cooling. Sol. Energy Mater. Sol. Cells 2018, 178, 115128,  DOI: 10.1016/j.solmat.2018.01.015
    13. 13
      Sato, D.; Yamada, N. Review of photovoltaic module cooling methods and performance evaluation of the radiative cooling method. Renewable and Sustainable Energy Reviews 2019, 104, 151166,  DOI: 10.1016/j.rser.2018.12.051
    14. 14
      Ahmed, S.; Li, Z.; Javed, M. S.; Ma, T. A review on the integration of radiative cooling and solar energy harvesting. Materials Today Energy 2021, 21, 100776,  DOI: 10.1016/j.mtener.2021.100776
    15. 15
      Chen, J.; Lu, L. Development of radiative cooling and its integration with buildings: A comprehensive review. Sol. Energy 2020, 212, 125151,  DOI: 10.1016/j.solener.2020.10.013
    16. 16
      Lu, X.; Xu, P.; Wang, H.; Yang, T.; Hou, J. Cooling potential and applications prospects of passive radiative cooling in buildings: The current state-of-the-art. Renewable and Sustainable Energy Reviews 2016, 65, 10791097,  DOI: 10.1016/j.rser.2016.07.058
    17. 17
      Li, W.; Li, Y.; Shah, K. W. A materials perspective on radiative cooling structures for buildings. Sol. Energy 2020, 207, 247269,  DOI: 10.1016/j.solener.2020.06.095
    18. 18
      Chen, L.; Zhang, K.; Ma, M.; Tang, S.; Li, F.; Niu, X. Sub-ambient radiative cooling and its application in buildings. Building Simulation 2020, 13, 11651189,  DOI: 10.1007/s12273-020-0646-x
    19. 19
      Pirvaram, A.; Talebzadeh, N.; Leung, S. N.; O’Brien, P. G. Radiative cooling for buildings: A review of techno-enviro-economics and life-cycle assessment methods. Renewable and Sustainable Energy Reviews 2022, 162, 112415,  DOI: 10.1016/j.rser.2022.112415
    20. 20
      Suhendri; Hu, M.; Su, Y.; Darkwa, J.; Riffat, S. Implementation of passive radiative cooling technology in buildings: A review. Buildings 2020, 10 (12), 215,  DOI: 10.3390/buildings10120215
    21. 21
      Hanif, M.; Mahlia, T. M. I.; Zare, A.; Saksahdan, T. J.; Metselaar, H. S. C. Potential energy savings by radiative cooling system for a building in tropical climate. Renewable and sustainable energy reviews 2014, 32, 642650,  DOI: 10.1016/j.rser.2014.01.053
    22. 22
      Zhang, J.; Yuan, J.; Liu, J.; Zhou, Z.; Sui, J.; Xing, J.; Zuo, J. Cover shields for sub-ambient radiative cooling: A literature review. Renewable and Sustainable Energy Reviews 2021, 143, 110959,  DOI: 10.1016/j.rser.2021.110959
    23. 23
      Liu, J.; Zhang, J.; Zhang, D.; Jiao, S.; Xing, J.; Tang, H.; Zhang, Y.; Li, S.; Zhou, Z.; Zuo, J. Sub-ambient radiative cooling with wind cover. Renewable and Sustainable Energy Reviews 2020, 130, 109935,  DOI: 10.1016/j.rser.2020.109935
    24. 24
      Vilà, R.; Martorell, I.; Medrano, M.; Castell, A. Adaptive covers for combined radiative cooling and solar heating. A review of existing technology and materials. Sol. Energy Mater. Sol. Cells 2021, 230, 111275,  DOI: 10.1016/j.solmat.2021.111275
    25. 25
      Wang, J.; Tan, G.; Yang, R.; Zhao, D. Materials, structures, and devices for dynamic radiative cooling. Cell Reports Physical Science 2022, 3, 101198,  DOI: 10.1016/j.xcrp.2022.101198
    26. 26
      An, Y.; Fu, Y.; Dai, J. G.; Yin, X.; Lei, D. Switchable radiative cooling technologies for smart thermal management. Cell Reports Physical Science 2022, 3 (10), 101098,  DOI: 10.1016/j.xcrp.2022.101098
    27. 27
      Taylor, S.; Long, L.; McBurney, R.; Sabbaghi, P.; Chao, J.; Wang, L. Spectrally-selective vanadium dioxide based tunable metafilm emitter for dynamic radiative cooling. Sol. Energy Mater. Sol. Cells 2020, 217, 110739,  DOI: 10.1016/j.solmat.2020.110739
    28. 28
      Xu, X.; Gu, J.; Zhao, H.; Zhang, X.; Dou, S.; Li, Y.; Zhao, J.; Zhan, Y.; Li, X. Passive and dynamic phase-change-based radiative cooling in outdoor weather. ACS Appl. Mater. Interfaces 2022, 14 (12), 1431314320,  DOI: 10.1021/acsami.1c23401
    29. 29
      Wang, S.; Jiang, T.; Meng, Y.; Yang, R.; Tan, G.; Long, Y. Scalable thermochromic smart windows with passive radiative cooling regulation. Science 2021, 374 (6574), 15011504,  DOI: 10.1126/science.abg0291
    30. 30
      Taylor, S.; Yang, Y.; Wang, L. Vanadium dioxide based Fabry-Perot emitter for dynamic radiative cooling applications. Journal of Quantitative Spectroscopy and Radiative Transfer 2017, 197, 7683,  DOI: 10.1016/j.jqsrt.2017.01.014
    31. 31
      Butler, A.; Argyropoulos, C. Mechanically tunable radiative cooling for adaptive thermal control. Applied Thermal Engineering 2022, 211, 118527,  DOI: 10.1016/j.applthermaleng.2022.118527
    32. 32
      Liu, J.; Zhou, Z.; Zhang, J.; Feng, W.; Zuo, J. Advances and challenges in commercializing radiative cooling. Materials Today Physics 2019, 11, 100161,  DOI: 10.1016/j.mtphys.2019.100161
    33. 33
      Cui, Y.; Luo, X.; Zhang, F.; Sun, L.; Jin, N.; Yang, W. Progress of passive daytime radiative cooling technologies towards commercial applications. Particuology 2022, 67, 5767,  DOI: 10.1016/j.partic.2021.10.004
    34. 34
      Jeon, S.; Shin, J. Ideal spectral emissivity for radiative cooling of earthbound objects. Sci. Rep. 2020, 10 (1), 13038,  DOI: 10.1038/s41598-020-70105-y
    35. 35
      Fan, S.; Li, W. Photonics and thermodynamics concepts in radiative cooling. Nat. Photonics 2022, 16 (3), 182190,  DOI: 10.1038/s41566-021-00921-9
    36. 36
      Chen, Z.; Zhu, L.; Raman, A.; Fan, S. Radiative cooling to deep sub-freezing temperatures through a 24-h day-night cycle. Nat. Commun. 2016, 7 (1), 13729,  DOI: 10.1038/ncomms13729
    37. 37
      Chamoli, S. K.; Li, W.; Guo, C.; ElKabbash, M. Angularly selective thermal emitters for deep subfreezing daytime radiative cooling. Nanophotonics 2022, 11 (16), 37093717,  DOI: 10.1515/nanoph-2022-0032
    38. 38
      Lin, S. Y.; Fleming, J. G.; Chow, E.; Bur, J.; Choi, K. K.; Goldberg, A. Enhancement and suppression of thermal emission by a three-dimensional photonic crystal. Phys. Rev. B 2000, 62 (4), R2243,  DOI: 10.1103/PhysRevB.62.R2243
    39. 39
      Schuller, J. A.; Taubner, T.; Brongersma, M. L. Optical antenna thermal emitters. Nat. Photonics 2009, 3 (11), 658661,  DOI: 10.1038/nphoton.2009.188
    40. 40
      Greffet, J. J. Controlled incandescence. Nature 2011, 478 (7368), 191192,  DOI: 10.1038/478191a
    41. 41
      Narayanaswamy, A.; Chen, G. Thermal emission control with one-dimensional metallodielectric photonic crystals. Phys. Rev. B 2004, 70 (12), 125101,  DOI: 10.1103/PhysRevB.70.125101
    42. 42
      Celanovic, I.; Perreault, D.; Kassakian, J. Resonant-cavity enhanced thermal emission. Phys. Rev. B 2005, 72 (7), 075127,  DOI: 10.1103/PhysRevB.72.075127
    43. 43
      Rephaeli, E.; Fan, S. Absorber and emitter for solar thermo-photovoltaic systems to achieve efficiency exceeding the Shockley-Queisser limit. Opt. Express 2009, 17 (17), 1514515159,  DOI: 10.1364/OE.17.015145
    44. 44
      Le Gall, J.; Olivier, M.; Greffet, J. J. Experimental and theoretical study of reflection and coherent thermal emissionby a SiC grating supporting a surface-phonon polariton. Phys. Rev. B 1997, 55 (15), 10105,  DOI: 10.1103/PhysRevB.55.10105
    45. 45
      Luo, C.; Narayanaswamy, A.; Chen, G.; Joannopoulos, J. D. Thermal radiation from photonic crystals: a direct calculation. Phys. Rev. Lett. 2004, 93 (21), 213905,  DOI: 10.1103/PhysRevLett.93.213905
    46. 46
      Chan, D. L.; Soljačić, M.; Joannopoulos, J. D. Thermal emission and design in 2D-periodic metallic photonic crystal slabs. Opt. Express 2006, 14 (19), 87858796,  DOI: 10.1364/OE.14.008785
    47. 47
      Fleming, J. G.; Lin, S. Y.; El-Kady, I.; Biswas, R.; Ho, K. M. All-metallic three-dimensional photonic crystals with a large infrared bandgap. Nature 2002, 417 (6884), 5255,  DOI: 10.1038/417052a
    48. 48
      Rephaeli, E.; Fan, S. Tungsten black absorber for solar light with wide angular operation range. applied physics letters 2008, 92 (21), 211107,  DOI: 10.1063/1.2936997
    49. 49
      Arpin, K. A.; Losego, M. D.; Cloud, A. N.; Ning, H.; Mallek, J.; Sergeant, N. P.; Zhu, L.; Yu, Z.; Kalanyan, B.; Parsons, G. N.; Girolami, G. S.; Abelson, J. R.; Fan, S.; Braun, P. V. Three-dimensional self-assembled photonic crystals with high temperature stability for thermal emission modification. Nat. Commun. 2013, 4 (1), 2630,  DOI: 10.1038/ncomms3630
    50. 50
      Wang, M.; Hu, C.; Pu, M.; Huang, C.; Zhao, Z.; Feng, Q.; Luo, X. Truncated spherical voids for nearly omnidirectional optical absorption. Opt. Express 2011, 19 (21), 2064220649,  DOI: 10.1364/OE.19.020642
    51. 51
      Zhang, S.; Li, Y.; Feng, G.; Zhu, B.; Xiao, S.; Zhou, L.; Zhao, L. Strong infrared absorber: surface-microstructured Au film replicated from black silicon. Opt. Express 2011, 19 (21), 2046220467,  DOI: 10.1364/OE.19.020462
    52. 52
      Kecebas, M. A.; Menguc, M. P.; Kosar, A.; Sendur, K. Passive radiative cooling design with broadband optical thin-film filters. Journal of Quantitative Spectroscopy and Radiative Transfer 2017, 198, 179186,  DOI: 10.1016/j.jqsrt.2017.03.046
    53. 53
      Kecebas, M. A.; Menguc, M. P.; Kosar, A.; Sendur, K. Spectrally selective filter design for passive radiative cooling. JOSA B 2020, 37 (4), 11731182,  DOI: 10.1364/JOSAB.384181
    54. 54
      Kim, M.; Seo, J.; Yoon, S.; Lee, H.; Lee, J.; Lee, B. J. Optimization and performance analysis of a multilayer structure for daytime radiative cooling. Journal of Quantitative Spectroscopy and Radiative Transfer 2021, 260, 107475,  DOI: 10.1016/j.jqsrt.2020.107475
    55. 55
      Shi, Y.; Li, W.; Raman, A.; Fan, S. Optimization of multilayer optical films with a memetic algorithm and mixed integer programming. Acs Photonics 2018, 5 (3), 684691,  DOI: 10.1021/acsphotonics.7b01136
    56. 56
      Guan, Q.; Raza, A.; Mao, S. S.; Vega, L. F.; Zhang, T. Machine Learning-Enabled Inverse Design of Radiative Cooling Film with On-Demand Transmissive Color. ACS Photonics 2023, 10 (3), 715726,  DOI: 10.1021/acsphotonics.2c01857
    57. 57
      Chae, D.; Kim, M.; Jung, P.-H.; Son, S.; Seo, J.; Liu, Y.; Lee, B. J.; Lee, H. Spectrally selective inorganic-based multilayer emitter for daytime radiative cooling. ACS Appl. Mater. Interfaces 2020, 12 (7), 80738081,  DOI: 10.1021/acsami.9b16742
    58. 58
      Ma, H.; Yao, K.; Dou, S.; Xiao, M.; Dai, M.; Wang, L.; Zhao, H.; Zhao, J.; Li, Y.; Zhan, Y. Multilayered SiO2/Si3N4 photonic emitter to achieve high-performance all-day radiative cooling. Sol. Energy Mater. Sol. Cells 2020, 212, 110584,  DOI: 10.1016/j.solmat.2020.110584
    59. 59
      Palik, E. D., Ed.; Handbook of Optical Constants of solids, Vol. 3; Academic Press, 1998.
    60. 60
      Jeong, S. Y.; Tso, C. Y.; Ha, J.; Wong, Y. M.; Chao, C. Y.; Huang, B.; Qiu, H. Field investigation of a photonic multi-layered TiO2 passive radiative cooler in sub-tropical climate. Renewable Energy 2020, 146, 4455,  DOI: 10.1016/j.renene.2019.06.119
    61. 61
      Lee, G. J.; Kim, Y. J.; Kim, H. M.; Yoo, Y. J.; Song, Y. M. Colored, daytime radiative coolers with thin-film resonators for aesthetic purposes. Advanced Optical Materials 2018, 6 (22), 1800707,  DOI: 10.1002/adom.201800707
    62. 62
      Tikhonravov, A. V.; Trubetskov, M. K.; DeBell, G. W. Application of the needle optimization technique to the design of optical coatings. Applied optics 1996, 35 (28), 54935508,  DOI: 10.1364/AO.35.005493
    63. 63
      Vincent, P.; Cunha Sergio, G.; Jang, J.; Kang, I. M.; Park, J.; Kim, H.; Lee, M.; Bae, J.-H. Application of genetic algorithm for more efficient multi-layer thickness optimization in solar cells. Energies 2020, 13 (7), 1726,  DOI: 10.3390/en13071726
    64. 64
      Kou, J. L.; Jurado, Z.; Chen, Z.; Fan, S.; Minnich, A. J. Daytime radiative cooling using near-black infrared emitters. Acs Photonics 2017, 4 (3), 626630,  DOI: 10.1021/acsphotonics.6b00991
    65. 65
      Chae, D.; Lim, H.; So, S.; Son, S.; Ju, S.; Kim, W.; Rho, J.; Lee, H. Spectrally selective nanoparticle mixture coating for passive daytime radiative cooling. ACS Appl. Mater. Interfaces 2021, 13 (18), 2111921126,  DOI: 10.1021/acsami.0c20311
    66. 66
      Gangisetty, G.; Zevenhoven, R. A Review of Nanoparticle Material Coatings in Passive Radiative Cooling Systems Including Skylights. Energies 2023, 16 (4), 1975,  DOI: 10.3390/en16041975
    67. 67
      Cheng, Z.; Shuai, Y.; Gong, D.; Wang, F.; Liang, H.; Li, G. Optical properties and cooling performance analyses of single-layer radiative cooling coating with mixture of TiO2 particles and SiO2 particles. Science China Technological Sciences 2021, 64 (5), 10171029,  DOI: 10.1007/s11431-020-1586-9
    68. 68
      Huang, Z.; Ruan, X. Nanoparticle embedded double-layer coating for daytime radiative cooling. International journal of heat and mass transfer 2017, 104, 890896,  DOI: 10.1016/j.ijheatmasstransfer.2016.08.009
    69. 69
      Cheng, Z.; Wang, F.; Wang, H.; Liang, H.; Ma, L. Effect of embedded polydisperse glass microspheres on radiative cooling of a coating. International Journal of Thermal Sciences 2019, 140, 358367,  DOI: 10.1016/j.ijthermalsci.2019.03.014
    70. 70
      Bao, H.; Yan, C.; Wang, B.; Fang, X.; Zhao, C. Y.; Ruan, X. Double-layer nanoparticle-based coatings for efficient terrestrial radiative cooling. Sol. Energy Mater. Sol. Cells 2017, 168, 7884,  DOI: 10.1016/j.solmat.2017.04.020
    71. 71
      Huang, J.; Li, M.; Fan, D. Core-shell particles for devising high-performance full-day radiative cooling paint. Applied Materials Today 2021, 25, 101209,  DOI: 10.1016/j.apmt.2021.101209
    72. 72
      Hu, D.; Sun, S.; Du, P.; Lu, X.; Zhang, H.; Zhang, Z. Hollow core-shell particle-containing coating for passive daytime radiative cooling. Composites Part A: Applied Science and Manufacturing 2022, 158, 106949,  DOI: 10.1016/j.compositesa.2022.106949
    73. 73
      Zhai, Y.; Ma, Y.; David, S. N.; Zhao, D.; Lou, R.; Tan, G.; Yang, R.; Yin, X. Scalable-manufactured randomized glass-polymer hybrid metamaterial for daytime radiative cooling. Science 2017, 355 (6329), 10621066,  DOI: 10.1126/science.aai7899
    74. 74
      Ko, B.; Lee, D.; Badloe, T.; Rho, J. Metamaterial-based radiative cooling: towards energy-free all-day cooling. Energies 2019, 12 (1), 89,  DOI: 10.3390/en12010089
    75. 75
      Kravets, V. G.; Kabashin, A. V.; Barnes, W. L.; Grigorenko, A. N. Plasmonic surface lattice resonances: a review of properties and applications. Chem. Rev. 2018, 118 (12), 59125951,  DOI: 10.1021/acs.chemrev.8b00243
    76. 76
      Atwater, H. A.; Polman, A. Plasmonics for improved photovoltaic devices. Nature materials 2010, 9 (3), 205213,  DOI: 10.1038/nmat2629
    77. 77
      Utyushev, A. D.; Zakomirnyi, V. I.; Rasskazov, I. L. Collective lattice resonances: Plasmonics and beyond. Reviews in Physics 2021, 6, 100051,  DOI: 10.1016/j.revip.2021.100051
    78. 78
      Amendola, V.; Pilot, R.; Frasconi, M.; Maragò, O. M.; Iatì, M. A. Surface plasmon resonance in gold nanoparticles: a review. J. Phys.: Condens. Matter 2017, 29 (20), 203002,  DOI: 10.1088/1361-648X/aa60f3
    79. 79
      Cherqui, C.; Bourgeois, M. R.; Wang, D.; Schatz, G. C. Plasmonic surface lattice resonances: Theory and computation. Accounts of chemical research 2019, 52 (9), 25482558,  DOI: 10.1021/acs.accounts.9b00312
    80. 80
      Rodriguez, S. R. K.; Abass, A.; Maes, B.; Janssen, O. T. A.; Vecchi, G.; Gomez Rivas, J. Coupling bright and dark plasmonic lattice resonances. Physical Review X 2011, 1 (2), 021019,  DOI: 10.1103/PhysRevX.1.021019
    81. 81
      Humphrey, A. D.; Barnes, W. L. Plasmonic surface lattice resonances on arrays of different lattice symmetry. Phys. Rev. B 2014, 90 (7), 075404,  DOI: 10.1103/PhysRevB.90.075404
    82. 82
      Rephaeli, E.; Raman, A.; Fan, S. Ultrabroadband photonic structures to achieve high-performance daytime radiative cooling. Nano Lett. 2013, 13 (4), 14571461,  DOI: 10.1021/nl4004283
    83. 83
      Choi, M.; Seo, J.; Yoon, S.; Nam, Y.; Lee, J.; Lee, B. J. All-day radiative cooling using a grating-patterned PDMS film emitter. Applied Thermal Engineering 2022, 214, 118771,  DOI: 10.1016/j.applthermaleng.2022.118771
    84. 84
      Seo, J.; Choi, M.; Lee, J.; Lee, B. J. Optimization of a grating structure in hexagonal array with omnidirectional emission for daytime radiative cooling. Journal of Quantitative Spectroscopy and Radiative Transfer 2022, 284, 108165,  DOI: 10.1016/j.jqsrt.2022.108165
    85. 85
      Wong, R. Y.; Tso, C. Y.; Chao, C. Y.; Huang, B.; Wan, M. P. Ultra-broadband asymmetric transmission metallic gratings for subtropical passive daytime radiative cooling. Sol. Energy Mater. Sol. Cells 2018, 186, 330339,  DOI: 10.1016/j.solmat.2018.07.002
    86. 86
      Long, L.; Yang, Y.; Wang, L. Simultaneously enhanced solar absorption and radiative cooling with thin silica micro-grating coatings for silicon solar cells. Sol. Energy Mater. Sol. Cells 2019, 197, 1924,  DOI: 10.1016/j.solmat.2019.04.006
    87. 87
      Dai, Y.; Zhang, Z.; Ma, C. Radiative cooling with multilayered periodic grating under sunlight. Opt. Commun. 2020, 475, 126231,  DOI: 10.1016/j.optcom.2020.126231
    88. 88
      Hervé, A.; Drévillon, J.; Ezzahri, Y.; Joulain, K. Radiative cooling by tailoring surfaces with microstructures: Association of a grating and a multi-layer structure. Journal of Quantitative Spectroscopy and Radiative Transfer 2018, 221, 155163,  DOI: 10.1016/j.jqsrt.2018.09.015
    89. 89
      Hossain, M. M.; Jia, B.; Gu, M. A metamaterial emitter for highly efficient radiative cooling. Adv. Opt. Mater. 2015, 3 (8), 10471051,  DOI: 10.1002/adom.201500119
    90. 90
      Cui, Y.; He, Y.; Jin, Y.; Ding, F.; Yang, L.; Ye, Y.; Zhong, S.; Lin, Y.; He, S. Plasmonic and metamaterial structures as electromagnetic absorbers. Laser & Photonics Reviews 2014, 8 (4), 495520,  DOI: 10.1002/lpor.201400026
    91. 91
      Perrakis, G.; Tasolamprou, A. C.; Kenanakis, G.; Economou, E. N.; Tzortzakis, S.; Kafesaki, M. Combined nano and micro structuring for enhanced radiative cooling and efficiency of photovoltaic cells. Sci. Rep. 2021, 11 (1), 11552,  DOI: 10.1038/s41598-021-91061-1
    92. 92
      Zhao, B.; Lu, K.; Hu, M.; Liu, J.; Wu, L.; Xu, C.; Xuan, Q.; Pei, G. Radiative cooling of solar cells with micro-grating photonic cooler. Renewable Energy 2022, 191, 662668,  DOI: 10.1016/j.renene.2022.04.063
    93. 93
      Zhu, L.; Raman, A.; Wang, K. X.; Anoma, M. A.; Fan, S. Radiative cooling of solar cells. Optica 2014, 1 (1), 3238,  DOI: 10.1364/OPTICA.1.000032
    94. 94
      Zhao, B.; Hu, M.; Ao, X.; Pei, G. Performance analysis of enhanced radiative cooling of solar cells based on a commercial silicon photovoltaic module. Sol. Energy 2018, 176, 248255,  DOI: 10.1016/j.solener.2018.10.043
    95. 95
      Gentle, A. R.; Smith, G. B. Is enhanced radiative cooling of solar cell modules worth pursuing?. Sol. Energy Mater. Sol. Cells 2016, 150, 3942,  DOI: 10.1016/j.solmat.2016.01.039
    96. 96
      Yalcin, R. A.; Blandre, E.; Joulain, K.; Drévillon, J. Colored radiative cooling coatings with nanoparticles. ACS photonics 2020, 7 (5), 13121322,  DOI: 10.1021/acsphotonics.0c00513
    97. 97
      Xi, W.; Liu, Y.; Zhao, W.; Hu, R.; Luo, X. Colored radiative cooling: How to balance color display and radiative cooling performance. International Journal of Thermal Sciences 2021, 170, 107172,  DOI: 10.1016/j.ijthermalsci.2021.107172
    98. 98
      Kim, H. H.; Im, E.; Lee, S. Colloidal photonic assemblies for colorful radiative cooling. Langmuir 2020, 36 (23), 65896596,  DOI: 10.1021/acs.langmuir.0c00051
    99. 99
      Zhou, L.; Rada, J.; Song, H.; Ooi, B.; Yu, Z.; Gan, Q. Colorful surfaces for radiative cooling. Journal of Photonics for Energy 2021, 11 (4), 042107042107,  DOI: 10.1117/1.JPE.11.042107
    100. 100
      Son, S.; Jeon, S.; Chae, D.; Lee, S. Y.; Liu, Y.; Lim, H.; Oh, S. J.; Lee, H. Colored emitters with silica-embedded perovskite nanocrystals for efficient daytime radiative cooling. Nano Energy 2021, 79, 105461,  DOI: 10.1016/j.nanoen.2020.105461
    101. 101
      Zhu, W.; Droguet, B.; Shen, Q.; Zhang, Y.; Parton, T. G.; Shan, X.; Parker, R. M.; De Volder, M. F. L.; Deng, T.; Vignolini, S.; Li, T. Structurally colored radiative cooling cellulosic films. Advanced Science 2022, 9 (26), 2202061,  DOI: 10.1002/advs.202202061
    102. 102
      Blandre, E.; Yalcin, R. A.; Joulain, K.; Drévillon, J. Microstructured surfaces for colored and non-colored sky radiative cooling. Opt. Express 2020, 28 (20), 2970329713,  DOI: 10.1364/OE.401368
    103. 103
      Ding, Z.; Li, X.; Fan, X.; Xu, M.; Zhao, J.; Li, Y.; Xu, H. A review of the development of colored radiative cooling surfaces. Carbon Capture Science & Technology 2022, 4, 100066,  DOI: 10.1016/j.ccst.2022.100066
    104. 104
      Zhai, H.; Fan, D.; Li, Q. Scalable and paint-format colored coatings for passive radiative cooling. Sol. Energy Mater. Sol. Cells 2022, 245, 111853,  DOI: 10.1016/j.solmat.2022.111853
    105. 105
      Yalcin, R. A.; Blandre, E.; Joulain, K.; Drévillon, J. Colored radiative cooling coatings with fluorescence. Journal of Photonics for Energy 2021, 11 (3), 032104032104,  DOI: 10.1117/1.JPE.11.032104
    106. 106
      Min, S.; Jeon, S.; Yun, K.; Shin, J. All-color sub-ambient radiative cooling based on photoluminescence. ACS Photonics 2022, 9 (4), 11961205,  DOI: 10.1021/acsphotonics.1c01648
    107. 107
      Sheng, C.; An, Y.; Du, J.; Li, X. Colored radiative cooler under optical Tamm resonance. ACS Photonics 2019, 6 (10), 25452552,  DOI: 10.1021/acsphotonics.9b01005
    108. 108
      Lee, G. J.; Kim, Y. J.; Kim, H. M.; Yoo, Y. J.; Song, Y. M. Colored, daytime radiative coolers with thin-film resonators for aesthetic purposes. Advanced Optical Materials 2018, 6 (22), 1800707,  DOI: 10.1002/adom.201800707
    109. 109
      Mandal, J.; Fu, Y.; Overvig, A. C.; Jia, M.; Sun, K.; Shi, N. N.; Zhou, H.; Xiao, X.; Yu, N.; Yang, Y. Hierarchically porous polymer coatings for highly efficient passive daytime radiative cooling. Science 2018, 362 (6412), 315319,  DOI: 10.1126/science.aat9513
    110. 110
      Xiang, B.; Zhang, R.; Luo, Y.; Zhang, S.; Xu, L.; Min, H.; Tang, S.; Meng, X. 3D porous polymer film with designed pore architecture and auto-deposited SiO2 for highly efficient passive radiative cooling. Nano Energy 2021, 81, 105600,  DOI: 10.1016/j.nanoen.2020.105600
    111. 111
      Son, S.; Liu, Y.; Chae, D.; Lee, H. Cross-linked porous polymeric coating without a metal-reflective layer for sub-ambient radiative cooling. ACS Appl. Mater. Interfaces 2020, 12 (52), 5783257839,  DOI: 10.1021/acsami.0c14792
    112. 112
      Liu, J.; Tang, H.; Jiang, C.; Wu, S.; Ye, L.; Zhao, D.; Zhou, Z. Micro-Nano Porous Structure for Efficient Daytime Radiative Sky Cooling. Adv. Funct. Mater. 2022, 32 (44), 2206962,  DOI: 10.1002/adfm.202206962
    113. 113
      Chen, M.; Pang, D.; Mandal, J.; Chen, X.; Yan, H.; He, Y.; Yu, N.; Yang, Y. Designing mesoporous photonic structures for high-performance passive daytime radiative cooling. Nano Lett. 2021, 21 (3), 14121418,  DOI: 10.1021/acs.nanolett.0c04241
    114. 114
      Sun, J.; Wang, J.; Guo, T.; Bao, H.; Bai, S. Daytime passive radiative cooling materials based on disordered media: A review. Sol. Energy Mater. Sol. Cells 2022, 236, 111492,  DOI: 10.1016/j.solmat.2021.111492
    115. 115
      Li, D.; Liu, X.; Li, W.; Lin, Z.; Zhu, B.; Li, Z.; Li, J.; Li, B.; Fan, S.; Xie, J.; Zhu, J. Scalable and hierarchically designed polymer film as a selective thermal emitter for high-performance all-day radiative cooling. Nat. Nanotechnol. 2021, 16 (2), 153158,  DOI: 10.1038/s41565-020-00800-4
    116. 116
      Wang, T.; Wu, Y.; Shi, L.; Hu, X.; Chen, M.; Wu, L. A structural polymer for highly efficient all-day passive radiative cooling. Nat. Commun. 2021, 12 (1), 365,  DOI: 10.1038/s41467-020-20646-7
    117. 117
      Mandal, J.; Yang, Y.; Yu, N.; Raman, A. P. Paints as a scalable and effective radiative cooling technology for buildings. Joule 2020, 4 (7), 13501356,  DOI: 10.1016/j.joule.2020.04.010
    118. 118
      Family, R.; Mengüç, M. P. Materials for radiative cooling: a review. Procedia environmental sciences 2017, 38, 752759,  DOI: 10.1016/j.proenv.2017.03.158
    119. 119
      Eriksson, T. S.; Lushiku, E. M.; Granqvist, C. G. Materials for radiative cooling to low temperature. Solar energy materials 1984, 11 (3), 149161,  DOI: 10.1016/0165-1633(84)90067-4
    120. 120
      Pirouzfam, N.; Menguc, M. P.; Sendur, K. Colorization of passive radiative cooling coatings using plasmonic effects. Sol. Energy Mater. Sol. Cells 2023, 253, 112225,  DOI: 10.1016/j.solmat.2023.112225
    121. 121
      Dou, S.; Xu, H.; Zhao, J.; Zhang, K.; Li, N.; Lin, Y.; Pan, L.; Li, Y. Bioinspired microstructured materials for optical and thermal regulation. Adv. Mater. 2021, 33 (6), 2000697,  DOI: 10.1002/adma.202000697
    122. 122
      Fu, S. C.; Zhong, X. L.; Zhang, Y.; Lai, T. W.; Chan, K. C.; Lee, K. Y.; Chao, C. Y. Bio-inspired cooling technologies and the applications in buildings. Energy and Buildings 2020, 225, 110313,  DOI: 10.1016/j.enbuild.2020.110313
    123. 123
      Shi, N. N. Biological and Bioinspired Photonic Materials for Passive Radiative Cooling and Waveguiding . Ph.D. Thesis, Columbia University, 2018.
    124. 124
      Yang, J.; Zhang, X.; Zhang, X.; Wang, L.; Feng, W.; Li, Q. Beyond the visible: bioinspired infrared adaptive materials. Adv. Mater. 2021, 33 (14), 2004754,  DOI: 10.1002/adma.202004754
    125. 125
      Shi, N. N.; Tsai, C. C.; Camino, F.; Bernard, G. D.; Yu, N.; Wehner, R. Keeping cool: Enhanced optical reflection and radiative heat dissipation in Saharan silver ants. Science 2015, 349 (6245), 298301,  DOI: 10.1126/science.aab3564
    126. 126
      Shi, N. N.; Tsai, C. C.; Camino, F.; Bernard, G. D.; Wehner, R.; Yu, N. Radiative cooling nano-photonic structures discovered in saharan silver ants and related biomimetic metasurfaces. In CLEO: QELS_Fundamental Science , San Jose, California, June 2016.  DOI: 10.1364/CLEO_QELS.2016.FTh3B.1 .
    127. 127
      Jeong, S. Y.; Tso, C. Y.; Wong, Y. M.; Chao, C. Y. FDTD simulations inspired by the daytime passive radiative cooling of the Sahara silver ant. In Proceedings of 4th International Conference on Building Energy and Environment , Melbourne, Australia, February 2018.
    128. 128
      Wu, W.; Lin, S.; Wei, M.; Huang, J.; Xu, H.; Lu, Y.; Song, W. Flexible passive radiative cooling inspired by Saharan silver ants. Sol. Energy Mater. Sol. Cells 2020, 210, 110512,  DOI: 10.1016/j.solmat.2020.110512
    129. 129
      Lin, S.; Ai, L.; Zhang, J.; Bu, T.; Li, H.; Huang, F.; Zhang, J.; Lu, Y.; Song, W. Silver ants-inspired flexible photonic architectures with improved transparency and heat radiation for photovoltaic devices. Sol. Energy Mater. Sol. Cells 2019, 203, 110135,  DOI: 10.1016/j.solmat.2019.110135
    130. 130
      Li, T.; Zhai, Y.; He, S.; Gan, W.; Wei, Z.; Heidarinejad, M.; Dalgo, D.; Mi, R.; Zhao, X.; Song, J.; Dai, J.; Chen, C.; Aili, A.; Vellore, A.; Martini, A.; Yang, R.; Srebric, J.; Yin, X.; Hu, L. A radiative cooling structural material. Science 2019, 364 (6442), 760763,  DOI: 10.1126/science.aau9101
    131. 131
      Chowdhury, F. I.; Xu, Q.; Sinha, K.; Wang, X. Cellulose-upgraded polymer films for radiative sky cooling. Journal of Quantitative Spectroscopy and Radiative Transfer 2021, 272, 107824,  DOI: 10.1016/j.jqsrt.2021.107824
    132. 132
      Gamage, S.; Banerjee, D.; Alam, M. M.; Hallberg, T.; Akerlind, C.; Sultana, A.; Shanker, R.; Berggren, M.; Crispin, X.; Kariis, H.; Zhao, D.; Jonsson, M. P. Reflective and transparent cellulose-based passive radiative coolers. Cellulose 2021, 28 (14), 93839393,  DOI: 10.1007/s10570-021-04112-1
    133. 133
      Chen, X.; He, M.; Feng, S.; Xu, Z.; Peng, H.; Shi, S.; Liu, C.; Zhou, Y. Cellulose-based porous polymer film with auto-deposited TiO2 as spectrally selective materials for passive daytime radiative cooling. Opt. Mater. 2021, 120, 111431,  DOI: 10.1016/j.optmat.2021.111431
    134. 134
      Jaramillo-Fernandez, J.; Yang, H.; Schertel, L.; Whitworth, G. L.; Garcia, P. D.; Vignolini, S.; Sotomayor-Torres, C. M. Highly-scattering cellulose-based films for radiative cooling. Advanced Science 2022, 9 (8), 2104758,  DOI: 10.1002/advs.202104758
    135. 135
      Chen, Y.; Dang, B.; Fu, J.; Wang, C.; Li, C.; Sun, Q.; Li, H. Cellulose-based hybrid structural material for radiative cooling. Nano Lett. 2021, 21 (1), 397404,  DOI: 10.1021/acs.nanolett.0c03738
    136. 136
      Tian, Y.; Shao, H.; Liu, X.; Chen, F.; Li, Y.; Tang, C.; Zheng, Y. Superhydrophobic and recyclable cellulose-fiber-based composites for high-efficiency passive radiative cooling. ACS Appl. Mater. Interfaces 2021, 13 (19), 2252122530,  DOI: 10.1021/acsami.1c04046
    137. 137
      Cheng, Z.; Han, H.; Wang, F.; Yan, Y.; Shi, X.; Liang, H.; Zhang, X.; Shuai, Y. Efficient radiative cooling coating with biomimetic human skin wrinkle structure. Nano Energy 2021, 89, 106377,  DOI: 10.1016/j.nanoen.2021.106377
    138. 138
      Lauster, T.; Mauel, A.; Herrmann, K.; Veitengruber, V.; Song, Q.; Senker, J.; Retsch, M. From Chitosan to Chitin: Bio-Inspired Thin Films for Passive Daytime Radiative Cooling. Advanced Science 2023, 10, 2206616,  DOI: 10.1002/advs.202206616
    139. 139
      Liu, B.-Y.; Xue, C.-H.; Zhong, H.-M.; Guo, X.-J.; Wang, H.-D.; Li, H.-G.; Du, M.-M.; Huang, M.-C.; Wei, R.-X.; Song, L.-G.; Chang, B.; Wang, Z. Multi-bioinspired self-cleaning energy-free cooling coatings. Journal of Materials Chemistry A 2021, 9 (43), 2427624282,  DOI: 10.1039/D1TA07953K
    140. 140
      Yang, Z.; Sun, H.; Xi, Y.; Qi, Y.; Mao, Z.; Wang, P.; Zhang, J. Bio-inspired structure using random, three-dimensional pores in the polymeric matrix for daytime radiative cooling. Sol. Energy Mater. Sol. Cells 2021, 227, 111101,  DOI: 10.1016/j.solmat.2021.111101
    141. 141
      Wang, S.; Wang, Y.; Zou, Y.; Chen, G.; Ouyang, J.; Jia, D.; Zhou, Y. Biologically inspired scalable-manufactured dual-layer coating with a hierarchical micropattern for highly efficient passive radiative cooling and robust superhydrophobicity. ACS Appl. Mater. Interfaces 2021, 13 (18), 2188821897,  DOI: 10.1021/acsami.1c05651
    142. 142
      Jeong, S. Y.; Tso, C. Y.; Wong, Y. M.; Chao, C. Y.; Huang, B. Daytime passive radiative cooling by ultra emissive bio-inspired polymeric surface. Sol. Energy Mater. Sol. Cells 2020, 206, 110296,  DOI: 10.1016/j.solmat.2019.110296
    143. 143
      Yang, Z.; Zhang, J. Bioinspired radiative cooling structure with randomly stacked fibers for efficient all-day passive cooling. ACS Appl. Mater. Interfaces 2021, 13 (36), 4338743395,  DOI: 10.1021/acsami.1c12267
    144. 144
      Yang, M.; Zou, W.; Guo, J.; Qian, Z.; Luo, H.; Yang, S.; Zhao, N.; Pattelli, L.; Xu, J.; Wiersma, D. S. Bioinspired “skin” with cooperative thermo-optical effect for daytime radiative cooling. ACS Appl. Mater. Interfaces 2020, 12 (22), 2528625293,  DOI: 10.1021/acsami.0c03897
    145. 145
      Zhang, H.; Ly, K. C. S.; Liu, X.; Chen, Z.; Yan, M.; Wu, Z.; Wang, X.; Zheng, Y.; Zhou, H.; Fan, T. Biologically inspired flexible photonic films for efficient passive radiative cooling. Proc. Natl. Acad. Sci. U. S. A. 2020, 117 (26), 1465714666,  DOI: 10.1073/pnas.2001802117
    146. 146
      Didari, A.; Mengüç, M. P. A biomimicry design for nanoscale radiative cooling applications inspired by Morpho didius butterfly. Sci. Rep. 2018, 8 (1), 16891,  DOI: 10.1038/s41598-018-35082-3
    147. 147
      Didari-Bader, A.; Pinar Mengüç, M. Near-field radiative transfer for biologically inspired structures. In Light, Plasmonics and Particles; Pinar Mengüç, M., Francoeur, M., Eds.; Elsevier, May 2023; Chapter 22.
    148. 148
      Choi, S. H.; Kim, S.-W.; Ku, Z.; Visbal-Onufrak, M. A.; Kim, S.-R.; Choi, K.-H.; Ko, H.; Choi, W.; Urbas, A. M.; Goo, T.-W.; Kim, Y. L. Anderson light localization in biological nanostructures of native silk. Nat. Commun. 2018, 9 (1), 452,  DOI: 10.1038/s41467-017-02500-5
    149. 149
      Hsu, P.-C.; Song, A. Y.; Catrysse, P. B.; Liu, C.; Peng, Y.; Xie, J.; Fan, S.; Cui, Y. Radiative human body cooling by nanoporous polyethylene textile. Science 2016, 353 (6303), 10191023,  DOI: 10.1126/science.aaf5471
    150. 150
      Tong, J. K.; Huang, X.; Boriskina, S. V.; Loomis, J.; Xu, Y.; Chen, G. Infrared-transparent visible-opaque fabrics for wearable personal thermal management. Acs Photonics 2015, 2 (6), 769778,  DOI: 10.1021/acsphotonics.5b00140
    151. 151
      Catrysse, P. B.; Song, A. Y.; Fan, S. Photonic structure textile design for localized thermal cooling based on a fiber blending scheme. ACS Photonics 2016, 3 (12), 24202426,  DOI: 10.1021/acsphotonics.6b00644
    152. 152
      Hsu, P.-C.; Liu, C.; Song, A. Y.; Zhang, Z.; Peng, Y.; Xie, J.; Liu, K.; Wu, C.-L.; Catrysse, P. B.; Cai, L.; Zhai, S.; Majumdar, A.; Fan, S.; Cui, Y. A dual-mode textile for human body radiative heating and cooling. Science Advances 2017, 3 (11), e1700895  DOI: 10.1126/sciadv.1700895
    153. 153
      Peng, Y.; Chen, J.; Song, A. Y.; Catrysse, P. B.; Hsu, P.-C.; Cai, L.; Liu, B.; Zhu, Y.; Zhou, G.; Wu, D. S.; Lee, H. R.; Fan, S.; Cui, Y. Nanoporous polyethylene microfibres for large-scale radiative cooling fabric. Nature Sustainability 2018, 1 (2), 105112,  DOI: 10.1038/s41893-018-0023-2
    154. 154
      Hsu, P. C.; Li, X. Photon-engineered radiative cooling textiles. Science 2020, 370 (6518), 784785,  DOI: 10.1126/science.abe4476
    155. 155
      Cai, L.; Song, A. Y.; Li, W.; Hsu, P.-C.; Lin, D.; Catrysse, P. B.; Liu, Y.; Peng, Y.; Chen, J.; Wang, H.; Xu, J.; Yang, A.; Fan, S.; Cui, Y. Spectrally selective nanocomposite textile for outdoor personal cooling. Adv. Mater. 2018, 30 (35), 1802152,  DOI: 10.1002/adma.201802152
    156. 156
      Peng, Y.; Cui, Y. Advanced textiles for personal thermal management and energy. Joule 2020, 4 (4), 724742,  DOI: 10.1016/j.joule.2020.02.011
    157. 157
      Luo, H.; Li, Q.; Du, K.; Xu, Z.; Zhu, H.; Liu, D.; Cai, L.; Ghosh, P.; Qiu, M. An ultra-thin colored textile with simultaneous solar and passive heating abilities. Nano Energy 2019, 65, 103998,  DOI: 10.1016/j.nanoen.2019.103998
    158. 158
      Luo, H.; Zhu, Y.; Xu, Z.; Hong, Y.; Ghosh, P.; Kaur, S.; Wu, M.; Yang, C.; Qiu, M.; Li, Q. Outdoor personal thermal management with simultaneous electricity generation. Nano Lett. 2021, 21 (9), 38793886,  DOI: 10.1021/acs.nanolett.1c00400
    159. 159
      Byers, H. R.; Landsberg, H. E.; Wexler, H.; Haurwitz, B.; Spilhaus, A. F.; Willett, H. C.; Buettner, K. J. Physical Aspects of Human Bioclimatology. In Compendium of Meteorology; Committee on the Compendium of Meteorology, 1951; pp 11121125.
    160. 160
      Palik, E. D., Ed.; Handbook of Optical Constants of Solids, Vol. 3; Academic Press, 1998.
    161. 161
      Siefke, T.; Kroker, S.; Pfeiffer, K.; Puffky, O.; Dietrich, K.; Franta, D.; Ohlidal, I.; Szeghalmi, A.; Kley, E.-B.; Tunnermann, A. Materials pushing the application limits of wire grid polarizers further into the deep ultraviolet spectral range. Advanced Optical Materials 2016, 4 (11), 17801786,  DOI: 10.1002/adom.201600250

Pair your accounts.

Export articles to Mendeley

Get article recommendations from ACS based on references in your Mendeley library.

Pair your accounts.

Export articles to Mendeley

Get article recommendations from ACS based on references in your Mendeley library.

You’ve supercharged your research process with ACS and Mendeley!

STEP 1:
Click to create an ACS ID

Please note: If you switch to a different device, you may be asked to login again with only your ACS ID.

Please note: If you switch to a different device, you may be asked to login again with only your ACS ID.

Please note: If you switch to a different device, you may be asked to login again with only your ACS ID.

MENDELEY PAIRING EXPIRED
Your Mendeley pairing has expired. Please reconnect