Photo-deposition of dual Ni(OH)2 and NixP cocatalysts on ZnIn2S4/ZnS for efficient photocatalytic hydrogen production

Efficient photocatalytic hydrogen production from water splitting remains a critical challenge for sustainable energy solutions. Here, we report dual Ni(OH)₂ (NO)/Ni_xP (NP) cocatalysts photo-deposited and ZnS decorated ZnIn₂S₄ photocatalyst (NOP/ZIS-Z). It exhibits efficient photocatalytic hydrogen production (PHP) with the rate of 5.46 mmol·g^-1·h^-1 and 420 nm quantum yield of 55.2% in triethanolamine (TEOA) system upon Xe lamp visible light combined with excellent stability. Impressively, its PHP rate reaches 0.54 mmol·g^-1·h^-1 in pure water under natural sunlight, showing tremendous practical potentials. The synergistic mechanism among ZnS, NO, and NP was revealed: (i) ZnS could transfer electron from ZIS and facilitates charge carrier separation, (ii) NP acts as reduction cocatalysts for proton reduction, (iii) NO functions as oxidation cocatalysts to trap holes for sacrificial reagent/water oxidation. Our work highlights coinstantaneous enhancing photocatalytic reduction and oxidation half-reaction by loading dual cocatalysts onto the heterojunctions.