Preparation Of Transition Metal Sulfide Composite Photocatalyst And Exploration Of Photocatalytic Performance Under Visible Light

Photocatalytic water splitting for H₂ evolution has become hot topic.H₂ as a renewable energy could be obtained from photocatalytic water splitting under visible light.Which is expected to solve the energy crisis and environmental problems.It is desirable to develop noble-metal-free catalyst because of the high cost of precious metal catalyst.However,traditional noble-metal-free catalyst,such as TiO₂,ZnO,has poor performance in photocatalytic water splitting.Recent years,transition metal sulfides have intrigued many interests.Cheap,abundant and specific properties,of electro-optical,making it desirable for substituting the noble metal in photocatalysis.Despite of this,sole transition metal sulfide photocatalyst could be performed barely satisfactory due to photocorrosion and high recombination of carriers.Hence,reasonable design transition metal sulfide composite photocatalyst may be a promising way for photocatalysis.In present work,CdS nanoparticles are fabricated by hot-inject method.And then,CuS nanoparticles and Co₃S₄ nanosheets are obtained by hydrothermal method and solvothermal method,respectively.Finally,CuS/CdS composite photocatalyst and CdS/Co₃S₄ composite photocatalyst are constructed by means of ultrasonic-adsorption and centrifugal-drying.The properties of these two composite photocatalysts are assessed through a series of characterization and activity studies.Among them,CuS/CdS composite photocatalyst can achieve a hydrogen evolution rate of 561.7?mol h^-1 and a quantum efficiency of 19.7%.CdS/Co₃S₄ composite photocatalyst can achieve a hydrogen evolution rate of 1083.9?mol h^-1 and a quantum efficiency of33.7%.CdS nanoparticles,here,are used as absorbents to provide photogenerated electron-hole pairs,while CuS and Co₃S₄ are served as cocatalyst to promote the separation of electron-hole pairs,accelerate electron transfer and provide active sites for photocatalytic reaction,thus improving photocatalytic performance.In this paper,the construction of transition metal sulfide-based composite photocatalyst provides a new idea for photocatalytic water splitting for H₂ production.