Design of CoN/ZIS heterojunction with yolk-shell structure for impressive photocatalytic H2 evolution promoted by the photothermal effect

Non-precious metal catalysts are the best choice for efficient use of solar energy and cost reduction. In this work, a non-noble metal catalyst with a yolk-shell structure CoN/SiO2 (CNS) was prepared and recombined with ZnIn2S4 (ZIS). The H2 evolution of CNS/ZIS was 17.168 mmol/h/g, meanwhile, the apparent quantum efficiency (AQE) was 20.69 %. The yolk-shell structure of CNS/ZIS greatly improves the catalytic stability, and the H2 evolution efficiency of four consecutive experiments can still reach 94 % for the first time. There are several reasons for the outstanding performance of CNS/ZIS catalysts: (1) The yolk-shell structure improves light absorption and creates numerous reaction sites. (2) The internal electric field formed by the heterostructure promotes the migration of carriers. (3) The photothermal effect accelerates catalytic kinetics and promotes H2 precipitation.