Water-Dispersible CsPbBr3 Perovskite Nanocrystals with Ultra-Stability and its Application in Electrochemical CO2 Reduction
Keqiang Chen, Kun Qi, Tong Zhou, Tingqiang Yang, Yupeng Zhang, Zhinan Guo, Chang‐Keun Lim, Jiayong Zhang, Igor Žutić, Han Zhang, Paras N. Prasad
Abstract
Abstract Thanks to the excellent optoelectronic properties, lead halide perovskites (LHPs) have been widely employed in high-performance optoelectronic devices such as solar cells and light-emitting diodes. However, overcoming their poor stability against water has been one of the biggest challenges for most applications. Herein, we report a novel hot-injection method in a Pb-poor environment combined with a well-designed purification process to synthesize water-dispersible CsPbBr 3 nanocrystals (NCs). The as-prepared NCs sustain their superior photoluminescence (91% quantum yield in water) for more than 200 days in an aqueous environment, which is attributed to a passivation effect induced by excess CsBr salts. Thanks to the ultra-stability of these LHP NCs, for the first time, we report a new application of LHP NCs, in which they are applied to electrocatalysis of CO 2 reduction reaction. Noticeably, they show significant electrocatalytic activity (faradaic yield: 32% for CH 4 , 40% for CO) and operation stability (> 350 h).