Water-Dispersible CsPbBr3 Perovskite Nanocrystals with Ultra-Stability and its Application in Electrochemical CO2 Reduction

• Main Authors: Keqiang Chen, Kun Qi, Tong Zhou, Tingqiang Yang, Yupeng Zhang, Zhinan Guo, Chang-Keun Lim, Jiayong Zhang, Igor Žutic, Han Zhang, Paras N. Prasad
• Format: Article
• Language: English
• Published: SpringerOpen 2021-08-01
• Series: Nano-Micro Letters
• Subjects: CsPbBr3 nanocrystals; Water-dispersible; Ultra-stability; Electrochemical CO2 reduction
• Online Access: https://doi.org/10.1007/s40820-021-00690-8
• ISSN: 2311-6706; 2150-5551

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 CsPbBr3 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 CO2 reduction reaction. Noticeably, they show significant electrocatalytic activity (faradaic yield: 32% for CH4, 40% for CO) and operation stability (> 350 h).