Boosting the photocatalytic hydrogen production activity of marigold-like Zn2In2S5 by using noble-metal-free Ni2P as cocatalyst

To enhance the activity of photocatalysts , it is crucial to use non-noble metal as a cocatalyst instead of noble metal in the arena of photocatalysis . In this study, to boost the photocatalytic hydrogen activity of pristine Zn 2 In 2 S 5 , XNi 2 P/ZIS 5 composite photocatalysts were prepared using noble-metal-free Ni 2 P as cocatalyst. Before photocatalytic hydrogen production experiments, the physicochemical properties of the synthesized materials were systematically characterized by advanced characterization methods. The experiment results demonstrate that the load of Ni 2 P cocatalyst can noticeably enhances the photocatalytic performance of Zn 2 In 2 S 5 and the photocatalytic hydrogen generation activities are observably influenced by the mass ratio of Ni 2 P to Zn 2 In 2 S 5 . Among XNi 2 P/ZIS 5 , the 10Ni 2 P/ZIS 5 sample presents the optimal hydrogen production rate of 17.74 mmol g −1  h −1 , which is 7.58 times as high as that of pristine Zn 2 In 2 S 5 . The increased photocatalytic hydrogen evolution activity could be attributed to the introduction of noble-metal-free cocatalyst Ni 2 P, which serves as an electronic collector and reduction sites remarkably facilitates the separation and migration of photoexcited electrons of Zn 2 In 2 S 5 . Meanwhile, the rate of reactions is significantly accelerated.