Insights into the Operation of Noble‐Metal‐Free Cocatalyst 1T‐WS2‐Decorated Zn0.5Cd0.5S for Enhanced Photocatalytic Hydrogen Evolution

Due to inefficient charge separation and low surface catalytic conversion efficiencies, cocatalysts are required for achieving photocatalytic hydrogen evolution. Being a noble-metal-free cocatalyst, metallic 1T-WS2 with excellent conductivity can function for this reaction. Herein, 1T-WS2 /Zn0.5 Cd0.5 S is constructed via a simple and feasible grinding approach. The composite containing 7.5 % 1T-WS2 in 1T-WS2 /Zn0.5 Cd0.5 S achieves a hydrogen evolution rate of 61.65 mmol g-1 h-1 and an external quantum efficiency of 8.04 % at 420 nm, which is 37 times that of bare Zn0.5 Cd0.5 S (1.67 mmol g-1 h-1 ). The electrical conductivity of metallic 1T-WS2 reduces the transfer impedance at the interface and thus accelerates the non-radiative energy transfer and electron transport rate. The different Fermi levels of 1T-WS2 and Zn0.5 Cd0.5 S form a Schottky junction, which promotes the transfer of photogenerated electrons from Zn0.5 Cd0.5 S to 1T-WS2 . More importantly, the close interface contact between 1T-WS2 and Zn0.5 Cd0.5 S results in strong electron interactions, which is conducive to the spatial separation of photogenerated electrons and holes. This work will further expand the application of 1T-WS2 in the photocatalytic hydrogen evolution process.