Construction of CsPbBr3/carboxyl-modified rGO heterostructures for efficient photocatalytic reduction of CO2 to methanol

Abstract

Solar-driven artificial photosynthesis by the use of photocatalysts to convert CO₂ into valuable chemical fuels provided a promising route to simultaneously alleviate the energy crisis and resolve environmental issues caused by CO₂. Among the many CO₂ reduction products, CH₃OH is very desirable, not only because of its use in the preparation of many commercial chemicals, but also it is easy to store and handle. However, the reduction to form CH₃OH directly was difficult to control. In recent years, CsPbBr₃ NCs have emerged as potential photocatalysts for CO₂ reduction due to their unique optoelectronic properties. Herein, the heterostructure of CsPbBr₃ and carboxyl-modified rGO (rGO-COOH) was designed for photocatalytic CO₂ reduction. In the solid-vapor reaction mode, only CO and CH₃OH were detected for all samples after 2 h of photocatalytic reaction. Through the construction of CsPbBr₃/rGO-COOH composites, the total yield of CO and CH₃OH products was 88.296 μmol g⁻¹ and 90.300 μmol g⁻¹, respectively. The average electron consumption rate (R_electron) was 359.196 μmol g⁻¹ h⁻¹, which was higher than that of previously reported CsPbBr₃-based catalysis. This study provides new insights for designing CsPbBr₃ composites and opens up new possibilities to utilize CsPbBr₃ NCs to obtain CH₃OH in photocatalytic applications.