Nickel hydroxide as a non-noble metal co-catalyst decorated on Cd0.5Zn0.5S solid solution for enhanced hydrogen evolution
Abstract
The study of non-noble metal photocatalysts provides practical significance for hydrogen evolution applications. Herein, new Cd0.5Zn0.5S/Ni(OH)2 catalysts were fabricated through simple hydrothermal and precipitation methods. The photocatalytic performance of the Cd0.5Zn0.5S/Ni(OH)2 composites under visible light was significantly improved, which was attributed to the wider visible light absorption range and less recombination of electron–hole pairs. The composite with a Ni(OH)2 content of 10% showed the best hydrogen evolution rate of 46.6 mmol g−1 h−1, which was almost 9 times higher than that of pristine Cd0.5Zn0.5S. The severe photo-corrosion of Cd0.5Zn0.5S was greatly improved, and the Cd0.5Zn0.5S/Ni(OH)2 composite exhibited a very high hydrogen evolution rate after three repeated tests. The excellent photocatalytic performance was due to the non-noble metal Ni(OH)2 co-catalyst. The excited electrons were transferred to the co-catalyst, which reduced electron–hole recombination. Moreover, the co-catalyst offered more sites for photocatalytic reactions. This study researched the mechanism of a co-catalyst composite, providing new possibilities for non-noble metal photocatalysts.