Fabrication of CZS NRs/NiSx NPs hybrids with abundant S-vacancies for signally promoting photocatalytic hydrogen production

The cocatalysts play a key role in photocatalytic technology in remarkably improving the efficiency of H2 evolution. Herein, S vacancies-rich Cd0.6Zn0.4S nanorods (CZS NRs) were prepared via solvothermal method. Then, as-obtained CZS NRs were modified with Ni–Co PBA-derived NiSx nanoparticles (NPs) cocatalyst using grinding method. The optimized CZS/NiSx-N-1.5 hybrids (CZS/NiSx-N, where N represents nickel nitrate which was used as nickel source) exhibited outstanding stability and activity, the average rate of H2 was up to 192.82 mmolg−1h−1 in deionized water medium, which was 201.4% higher than that of CZS. Besides, NiSx-A and NiSx-C cocatalysts with different particle sizes were obtained using nickel acetate (A) and nickel chloride (C) as nickel source, respectively. The CZS/NiSx-C-1.5 and CZS/NiSx-A-1.5 exhibited the H2 evolution rate of 180.70 and 201.93 mmolg−1h−1 in deionized water medium, respectively. The as-prepared materials also exhibited the excellent H2 evolution performance in natural seawater medium. Besides, the photocatalytic mechanism of H2 evolution over CZS NRs/NiSs NPs was also discussed. This work develops a novel H2 evolution cocatalyst and unveils the relationship between the loading amount/particle size of cocatalyst on the H2 evolution rate.