Hydrogen Evolution by an All-Solid-State Z-Scheme WO3 /Cu3P Photocatalytic Water Splitting System

Photocatalytic water splitting for hydrogen (H₂) evolution represents a pivotal strategy for sustainable energy production. Tungsten trioxide (WO₃) is one of the most investigated materials in the semiconductor photocatalysis research field. However, the pure WO₃ cannot perform the photocatalytic water splitting reaction because of its unsuitable band structure. In this study, to solve the aforementioned issues, we construct an all-solid-state Z-scheme WO₃/Cu₃P heterojunction photocatalyst to address the limitations of single-component systems. The photocatalytic activity testing results showed that when the loading amount of Cu₃P was 10% (mass ratio), WO₃/Cu₃P exhibited the highest photocatalytic activity for hydrogen production. Under the optimized reaction conditions, the synthesized WO₃/Cu₃P obtained a remarkable hydrogen evolution rate was about 50 µmol·g⁻¹·h⁻¹ when irradiated by a Xe lamp, without employing any sacrificial agents. The apparent quantum efficiency is about 0.66%. The photoelectrochemical test and luminescent spectrum results confirmed that the incorporation of Cu₃P nanoparticles enhances the transport and separation efficiency of photogenerated carriers, endowing WO₃ with the ability to produce hydrogen by photocatalytic water splitting. This work provides a new strategy for the design and synthesis of a phosphorus-based Z-scheme heterostructure photocatalyst.