Design and fabrication of Co9S8/Zn0.5Cd0.5S hollow nanocages with significantly enhanced photocatalytic hydrogen production activity

Designing and fabricating efficient photocatalysts for photocatalytic hydrogen evolution has drawn abundant attention in recent years. In this work, Co9S8/Zn0.5Cd0.5S hybrids were successfully synthesized. The Zn0.5Cd0.5S nanospheres were in-situ grown on the surface of Co9S8 co-catalysts with polyhedral hollow structure so that self-aggregation is suppressed. Moreover, the photocatalytic activity of Zn0.5Cd0.5S was exaggeratedly improved after introducing Co9S8 species and 10 wt% Co9S8/Zn0.5Cd0.5S sample exhibited an optimal H2 evolution rate of 10.9 mmol h−1 g−1. The improved catalytic performance may be ascribed to the efficient charge separation, resulting from the formation of built-in electric field between Zn0.5Cd0.5S and Co9S8. The mechanism has been investigated by the techniques of surface photovoltage spectroscopy (SPV), electron spin resonance (ESR) and the surface work function. This work may deliver some new insights on designing efficient photocatalysts with hierarchical architectures.