Construction of core–shell CeO2 nanorods/SnIn4S8 nanosheets heterojunction with rapid spatial electronic migration for effective wastewater purification and H2O2 production

Abstract

In order to promote green development and low-carbon transformation, the development of high-performance and multi-functional photocatalysts for green chemical production and environmental remediation has become a hot research topic. In this work, a novel core–shell CeO2 nanorods/SnIn4S8 nanosheets heterostructure (COSIS) was successfully fabricated. The photocatalytic degradation of methyl orange (MO), production of H2O2 and reduction of Cr (VI) were used to evaluate the multifunctional and practical application prospects of as-prepared COSIS materials. The results showed that the photocatalytic activities of COSIS heterostructures were significantly improved compared with the original SnIn4S8 and CeO2, and the optimized COSIS2 displayed the best photocatalytic activities. The kinetic rates of MO degradation, Cr (VI) reduction and H2O2 production over COSIS2 were 10.2, 17.4 and 39.1 times than those of CeO2 and 2.5, 3.8 and 7.2 times than those of SnIn4S8, respectively. The improved photocatalytic performance could be attributed to the construction of coaxial core–shell heterostructure and synergistic effect between SnIn4S8 and CeO2, which effectively improved the charge separation efficiency. The cyclic experiments and XRD patterns before and after recycling runs over COSIS2 heterostructure confirmed its good sustainability and recycling. Finally, the direct Z-scheme CeO2 nanorods/SnIn4S8 nanosheets core–shell heterojunction was proposed to explain the photocatalytic mechanism. This work will provide reference and guidance for constructing SnIn4S8-based core–shell heterojunction and designing multifunctional photocatalysts for industrial production and environmental governance.