Novel strategy for in situ construction of Cercis chinensis cluster-like photocatalytic heterojunctions

Abstract

Developing high-performance catalysts is a crucial area of research for efficiently utilizing light energy. In this study, a lamellar spherical structure of Cu2(OH)2CO3 was utilized to synthesize Cercis chinensis clustered CuO/g-C3N4 heterojunctions. These heterojunctions were then further improved through in situ orogenesis initiated by the steam and CO2 produced during the decomposition of Cu2(OH)2CO3. This strategy avoided the dilemma of multi-step synthesis of traditional heterojunctions, and further overcame the trouble of removing templates. The heterojunction results in a significant increase in CH4 production in the photocatalytic CO2 reduction reaction. The rate increases to 18.61 μmol g−1 h−1, which is 4.68 times higher than that of pure g-C3N4 and 16.32 times higher than that of CuO. Moreover, the heterojunction effective exciton separation, mass transfer, and distinct morphology result in a CH4 selectivity of over 75%. In comparison, pure g-C3N4 exhibits a CH4 selectivity of 52%, while CuO demonstrates a selectivity of 36.3%. This work provides a potential and simple strategy for the in situ construction of novel photocatalysts with heterojunctions and special morphologies.