Rationally Designed CeO2 Nanosheets over Co9S8 Nanoparticles form S‐Scheme Heterojunction for Efficient Hydrogen Production

Abstract

AbstractEnriching the active sites of catalysts and artificially regulating the directional migration of photogenerated carriers are effective means to improve the catalytic activity of photocatalysts. In this work, CeO2 nanosheets are prepared by calcination at high temperatures, and the S‐scheme heterojunction photocatalyst CeO2@Co9S8 is prepared by coupling the Co9S8 nanoparticles prepared by hydrothermal method on CeO2 nanosheets. The large specific surface area of CeO2 nanosheets provides sufficient loading sites for Co9S8 and Co9S8 nanoparticles can effectively disperse with the help of CeO2 nanosheet structure, which effectively inhibits the agglomeration of nanoparticles. The high photosensitivity of Co9S8 increases the utilization of CeO2@Co9S8 S‐scheme heterojunction to visible light. The construction of S‐scheme heterojunction improves the separation efficiency of photogenerated carriers, prolongs the service life of photogenerated charges, retains the photogenerated electrons and holes with strong reduction and oxidation ability in the catalyst system, and improves the performance of photocatalytic hydrogen production. The hydrogen yield of 15 wt% Co9S8 supported CeO2@Co9S8 can reach 15.7 times CeO2 and 2.5 times Co9S8, and the composite catalyst has good stability. This work provides a new way for adjusting the surface structure and carrier behavior of photocatalysts.