Efficient interfacial charge transfer of CeO2/Bi19Br3S27 S-scheme heterojunction for boosted photocatalytic CO2 reduction

Abstract

Improving the separation efficiency of photogenerated charge carriers to significantly enhance the redox capability of photocatalysts remains a major challenge in the field of photocatalysis. To address this issue, this study successfully synthesized a CeO₂/Bi₁₉Br₃S₂₇ S-scheme heterojunction catalyst using a hydrothermal method, aiming to enhance the photocatalytic performance of the catalyst. The synthesis of the CeO₂/Bi₁₉Br₃S₂₇ composite not only improved the separation efficiency of photogenerated charge carriers but also endowed the catalyst with stronger redox capabilities and greater driving force, significantly boosting its photocatalytic performance. Experimental results showed that the CO production rate of the CeO₂/Bi₁₉Br₃S₂₇ composite catalyst reached 13.5 ​μmol ​g⁻¹ ​h⁻¹, which is 5.19 times higher than that of the pure Bi₁₉Br₃S₂₇ catalyst and 2.81 times higher than that of the pure CeO₂ catalyst. This significant enhancement indicates that the CeO₂/Bi₁₉Br₃S₂₇ composite catalyst exhibited stronger catalytic performance in CO generation reactions. Furthermore, CeO₂/Bi₁₉Br₃S₂₇ catalyst achieved a CH₄ production rate of 4.3 ​μmol ​g⁻¹ ​h⁻¹, which is 3.1 times higher than that of the CeO₂ catalyst and 2.7 times higher than that of the Bi19Br3S27 catalyst, further confirming its superior performance in CH₄ generation reactions. These results demonstrate that the CeO₂/Bi₁₉Br₃S₂₇ composite catalyst not only shows significant improvements in CO and CH₄ production rates but also exhibits excellent photocatalytic performance, highlighting its potential application in the field of photocatalysis. This study provides new insights into improving the separation efficiency of photogenerated charges and offers valuable references for the future development of highly efficient photocatalytic materials. By constructing the S-scheme heterojunction structure, the recombination of photogenerated charge carriers can be effectively suppressed, thereby enhancing the efficiency of photocatalytic reactions and providing a new solution for sustainable energy utilization.