Noble metal-free bimetallic phosphide-decorated Zn 0.5 Cd 0.5 S with efficient photocatalytic H 2 evolution.

The rapid recombination of charge carriers in semiconductor-based photocatalysts results in a low photocatalytic activity. Co-catalysis is considered a promising strategy to improve the photocatalytic performance of semiconductors. In this study, a bimetallic phosphide was grown by a facile in situ growth method. Loading the cocatalyst (7 wt% NiCoP) leads to activity enhancement by a factor of approximately 27 times in the visible-light-driven hydrogen evolution relative to the pristine Zn 0.5 Cd 0.5 S. The photocatalysis shows a high hydrogen evolution rate of 19.5 mmol g -1 h -1 , which is much higher than that of the single metal phosphide (Ni 2 P: 7.0 mmol g -1 h -1 ; Co x P: 8.1 mmol g -1 h -1 ) and 7 wt% Pt modified Zn 0.5 Cd 0.5 S (0.3 mmol g -1 h -1 ). Its apparent quantum efficiency reaches 41.6% at 420 nm. Moreover, the photocatalyst exhibits a remarkable photostability for five consecutive cycles of photocatalytic activity measurements with a total reaction time of 15 hours. The excellent photocatalytic activity of the photocatalyst was attributed to the in situ -formed NiCoP cocatalyst, which not only acts as a reactive site but also accelerates the separation of charge carriers.