Hierarchical flower-like ZnIn2S4 anchored with well-dispersed Ni12P5 nanoparticles for high-quantum-yield photocatalytic H2 evolution under visible light

Abstract

Developing cost-effective, highly efficient and stable visible-light photocatalysts towards photocatalytic hydrogen (H₂) production from water splitting is critical for the conversion of renewable solar energy to chemical fuels. Herein, hierarchical flower-like ZnIn₂S₄ was synthesized by using a hydrothermal method, and subsequently coupled with Ni₁₂P₅ nanoparticles via a facile solution-phase method. Benefitting from the incorporation of nanostructured Ni₁₂P₅, which effectively facilitates charge separation and provides active sites for photocatalytic H₂ evolution, the as-prepared ZnIn₂S₄/Ni₁₂P₅ composite photocatalysts show high performance for H₂ production from aqueous solutions of Na₂S/Na₂SO₃ under visible light irradiation. In particular, the ZnIn₂S₄/Ni₁₂P₅ sample with an optimal loading of Ni₁₂P₅ exhibits a maximum H₂ evolution rate of 2263 μmol h⁻¹ g⁻¹ with an extremely high apparent quantum yield (AQY) of 20.5% at 420 nm. More importantly, the enhanced photocatalytic performance of the ZnIn₂S₄/Ni₁₂P₅ heterojunction was investigated by using photoelectrochemical (PEC) measurements. In short, this work highlights the importance of the interfacial design of transition metal phosphide-decorated ternary metal sulfide semiconductors towards efficient and stable photocatalysis.