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

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).

SUBMITTER: Chen K

PROVIDER: S-EPMC8360258 | biostudies-literature |

REPOSITORIES: biostudies-literature

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