A well-designed hierarchical Bi19S27Br3 nanorods@SnIn4S8 nanosheet core–shell S-scheme heterostructure for robust photothermal-assisted photocatalytic CO2 reduction

Abstract

Photocatalysis, which can use solar energy to convert carbon dioxide into chemical fuels, is one of the most promising techniques to mitigate the greenhouse effect. However, due to the insufficient utilization of solar energy, low photocatalytic efficiency and poor stability of photocatalysts, the development of photocatalytic CO₂ reduction technology is severely limited. In this study, Bi₁₉S₂₇Br₃ nanorod@SnIn₄S₈ nanosheet heterojunction composites with a novel core–shell structure are designed and prepared for the first time, and the excellent photothermal effect of Bi₁₉S₁₂Br₃ nanorods induced by near-infrared light absorption is successfully applied to photocatalytic reactions. Benefiting from the unique hierarchical architecture, close interfacial contact, special S-scheme charge transfer mode, and excellent photothermal synergism, the constructed Bi₁₉S₂₇Br₃@SnIn₄S₈ composite photocatalysts exhibit outstanding photothermal-assisted photocatalytic CO₂ reduction performance under full-spectrum irradiation. Without the addition of sacrificial agents and co-catalysts, the average CO yield is up to 35.63 μmol g⁻¹ h⁻¹, reaching 7.2 and 8.7 times higher than that of pure Bi₁₉S₂₇Br₃ and SnIn₄S₈ samples. This work provides a new strategy and idea for the development of high-performance composite photocatalysts.