Improved stability of CdSeS/ZnS quantum dots against temperature, humidity, and UV-O3 by encapsulation in crosslinked polystyrene beads

Cadmium-based quantum dot nanocrystals are promising optoelectronic materials due to their core/shell structure, excellent properties, and fascinating potential applications in LED, display, and photovoltaics. However, those materials are very sensitive to moisture, temperature, UV light, and polar solvents, and this greatly hinders their practical applications. Here, highly luminescent CdSeS/ZnS quantum dots-polystyrene composite beads with uniform morphology are prepared via a simple swelling–shrinking strategy. This process is carried out only in nonpolar toluene and hexane without the addition of any polar reagents. In addition, a Si-Al oxidation layer is coated on the hybrid beads for further protection. As a result, the as-prepared composite beads not only retain high luminescence but also exhibit superior water, temperature, and UV-O3-resistant properties.