In this work, C@ZnxCd1-xS/Co3O4 catalyst which with high hydrogen production activity was prepared and the catalyst was characterized by SEM, TEM, XRD, XPS, Uv-vis DRS charac- terization. After two-step modification, the light absorption intensity of C@ZnxCd1-xS and C@ZnxCd1-xS/Co3O4 showed an increasing trend compared with pure ZnxCd1-xS, such phenomenon was beneficial to the visible light absorption and utilization of photocatalyst. In addition, Mott-Schottky proved that ZnxCd1-xS catalyst formed p-n heterojunction with Co3O4 nanoparticles, which further demonstrated that the modification of ZnxCd1-xS by Co3O4 was successful. And the hydrogen production of C@ZnxCd1-xS/Co3O4 (30%) (1405.1 mu mol) was 6.9 times that of pure ZnxCd1-xS. The improvement of photocatalytic performance can be attributed to that carbon particles accelerate the storage and transfer of electrons, and the formation of p-n heterojunction between Co3O4 and ZnxCd1-xS promotes the separation of photogenerated carriers effectively. In this study, the introduction of amorphous carbon and Co3O4 promoted the transfer and separation of electrons and holes greatly, thereby inhibited the recombination of carriers and provided the favorable conditions for the preparation of highly efficient and stable photocatalysts. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.