High efficient and stable Z-scheme g-C3N4/Zn0.5Cd0.5S photocatalyst driven by visible light for hydrogen evolution

• A stable g-C 3 N 4 /ZnCdS photocatalyst is prepared by facile sintering method. • Hydrogen evolution rate reaches highest 16663 μmol•g −1 •h under visible light. • Z-scheme charge separation and transfer system forms. It is extremely desirable to develop efficient and cheap water splitting photocatalysts. An ultrahigh performance and stable photocatalyst g-C 3 N 4 /Zn 0.5 Cd 0.5 S was prepared by simple sintering method. g-C 3 N 4 nanosheets are evenly distributed around 20–30 nm ZnCdS nanoparticles, which can accelerate carriers separation and transfer, and increase the carriers life-time from 4.1 ns to 5.5 ns. UV–vis absorption spectra demonstrate that their absorption range can reach to visible light edge of 539 nm. The photocatalyst has a high photocatalytic hydrogen evolution rate of 16.66 mmol•h −1 •g −1 under visible light illumination (λ = 400–780 nm). Furthermore, after six recycles of photocatalyst, the hydrogen evolution stability still remains 94%. The excellent photocatalytic performance is attributed to the Z-scheme energy band structure formed between g-C 3 N 4 and Zn 0.5 Cd 0.5 S by simple sintering method. This work provides significant progress toward the synthesis of cheap Z-scheme photocatalysts for practical applications.