Enhanced photocatalytic hydrogen production of noble-metal free Ni-doped Zn(O,S) in ethanol solution

High efficient hydrogen evolved Ni-doped Zn(O,S) photocatalyst with different Ni amounts had been successfully synthesized with a simple method at low temperature. Our Ni-doped Zn(O,S) catalyst reached the highest hydrogen generation rate of 14,800 μmol g^?1 h^?1 or 0.92 mmol g^?1 h^?1 W^?1 corresponding to apparent quantum yield 31.5%, which was 2.3 times higher compared to the TiO₂/Pt used as a control in this work. It was found that a small amount of Ni doped into Zn(O,S) nanoparticles could increase the optical absorbance, lower the charge transfer resistance, accordingly decrease the electron-hole recombination rate, and significantly enhance the photocatalytic hydrogen evolution reaction (HER). The as-prepared catalyst has the characteristics of low cost, low power consumption for activating the catalytic HER, abundant and environmental friendly constituents, and low surface oxygen bonding for forming oxygen vacancies. The photocatalytic performance of Ni-doped Zn(O,S) was demonstrated with a proposed kinetic mechanism in this paper.