Synthesis of Double Trivalent Perovskite Quantum Dots Cs3BiSbX9 (X = Cl, Br, I) for Efficient CO2 Photoreduction Performance

• Published in: Small (Weinheim an der Bergstrasse, Germany) Germany), 2024-08, Vol.20 (35), p.e2401301-n/a
• Main Authors: Tian, Jie, Wang, Zhijian, Hou, Yaqin, Yang, Yatao, Chen, Haijun, Huang, Zhanggen
• Format: Article
• Language: English
• Subjects: Antimony; Bismuth; Carbon dioxide; Charge distribution; Electronegativity; Energy distribution; Halides; halogen; perovskite; Perovskites; Photochemical reactions; photoreduction; Quantum dots; Recrystallization; Room temperature; Surface charge
• ISSN: 1613-6810; 1613-6829; 1613-6829
• DOI: 10.1002/smll.202401301

Non‐toxic Bi halides have great potential in the field of CO2 photoreduction, but strong charge localization limits their charge separation and transfer. In this study, a series of Cs3BiSbX9 (X = Cl, Br, I) perovskite quantum dots (PQDs) are synthesized by antisolvent recrystallization at room temperature, in which Cs3BiSbBr9 PQDs has high selectivity (94.51%) and yield (15.32 µmol g−1 h−1) of CO2 to CO. In situ DRIFTS and theoretical calculations suggest that the surface charge can be tailored by halogen modulation, allowing for the customization of intermediate species. The Bi─Br─Sb symmetric charge distribution induced by the halogen Br promotes the formation of b─HCOO and reduces the reaction energy barrier of the rate‐limiting step, while the weak electronegativity of Cl and the high electronegativity of I leads to m─HCOO and ─COOH production, which are detrimental to CO generation. This work provides new insights into the design of halide alloy perovskites for CO2 photoreduction. A series of Cs3BiSbX9 (X = Cl, Br, I) alloy perovskite quantum dots (PQDs) with high carrier lifetime are synthesized by antisolvent for the first time. The halogen on Cs3BiSbX9 (X = Cl, Br, I) PQDs induces the interfacial charge reconfiguration mechanism and the rapid optical evolution of CO2 to CO.