Ceramic-like stable CsPbBr3 nanocrystals encapsulated in silica derived from molecular sieve templates

Abstract

Achieving good stability while maintaining excellent properties is one of the main challenges for enhancing the competitiveness of luminescent perovskite CsPbX3 (X=Cl, Br, I) nanocrystals (NCs). Here, we propose a facile strategy to synthesize ceramic-like stable and highly luminescent CsPbBr3 NCs by encapsulating them into silica derived from molecular sieve templates at high temperature (600–900 oC). The obtained CsPbBr3-SiO2 powders not only show high photoluminescence quantum yield (~71%), but also show an exceptional stability comparable to the ceramic Sr2SiO4:Eu2+ green phosphor. They can maintain 100% of their photoluminescence value under illumination on blue light-emitting diodes (LEDs) chips (20 mA, 2.7 V) for 1000 h, and can also survive in a harsh hydrochloric acid aqueous solution (1 M) for 50 days. We believe that the above robust stabilities will significantly enhance the potential of perovskite CsPbX3 NCs to be practically applied in LEDs and backlight displays.