Cart
Table of Contents
Teaching fluorescence. The cover features samples of polymer-embedded colloids of nanometer-sized cadmium selenide sulfide (CdSexS1−x), left two samples, and cadmium selenide (CdSe), right two samples, similar to those synthesized in general chemistry labs at the University of Iowa. When irradiated with light of energy greater than the band gap energy, these semiconducting colloids display band edge fluorescence. The light of the fluorescent emission has an energy (and associated color) that is approximately equal to the band gap energy of the material. When the samples are irradiated with ultraviolet light (λ = 365 nm), the emission colors range from violet to orange (bottom image). When green laser (λ = 532 nm) irradiation is added, only samples whose emission colors correspond to light of a lower energy than green light display significant fluorescence within the laser beam cross section (top image).
indicates the article is freely available through sponsorship by the author or related funding agency.
More about this program.
