Enhanced Hydrogen Evolution over Sea-Urchin-Structure NiCoP Decorated ZnCdS Photocatalyst

Abstract

Developing low-cost and high-catalytic photocatalysts is momentous to achieve efficient photocatalytic splitting of water to produce hydrogen. In this study, a 0D–3D structure ZnCdS–NiCoP composite was synthesized by a simple physical mixing method. A series of characterization results show that the close bonding of ZnCdS nanoparticles and NiCoP nanorods is conducive to electron transfer between the ZnCdS and NiCoP interface. The sea-urchin-structure NiCoP composed of nanorods could be as an electron acceptor to accelerate the directed migration of electrons. Thereby achieving separation of electrons and holes in space. Sea-urchin-structure NiCoP provides spatial support for ZnCdS, greatly reducing the degree of agglomeration of ZnCdS nanoparticles and increasing the specific surface area of the catalyst. The performance of the visible-light-driven photocatalyst showed that the ZnCdS–NiCoP10 composite had the highest photocatalytic hydrogen production activity, and the amount of hydrogen evolution in the reaction for 5 h was 789.7 μmol, which reached 5.2 times that of pure ZnCdS. The apparent quantum efficiency (AQE) of the ZnCdS–NiCoP10 composite was 6.28% at a wavelength of 475 nm. After 5 cycles of reaction, the composite ZnCdS–NiCoP10 maintained long-term stability. Based on the characterization analysis results, a possible mechanism of hydrogen production of by ZnCdS–NiCoP composite catalyst is proposed, which will help to understand the enhance photocatalytic hydrogen evolution activity of ZnCdS–NiCoP and may stimulate the synthesis of other 0D–3D catalytic systems.