Preparation And Photocatalytic Activity Of Ternary Sulfide Composite Photocatalysts With Full Spectral Response

Semiconductor photocatalysis technology is considered to be a shortcut to efficiently use solar energy to solve environmental pollution and energy shortage because it can use solar energy to purify pollutants,reduce heavy metal ions,and decompose water to produce oxygen,and has therefore attracted a large number of researchers.I-III-V ternary sulfides are a series of typical narrowband semiconductors,which can effectively use UV-visible light,so they are widely used in photocatalysis.However,the rapid recombination of photogenerated charges,photo corrosion of sulfides themselves,and inability to absorb infrared light limit their value in practical applications.Therefore,based on the heterojunction of ternary sulfide semiconductors equipped with other catalysts,this paper evaluates the effect of ternary sulfide semiconductors on their photocatalytic activity under different conditions.The main work contents are as follows:（1）Cu In S₂/In₂O₃ composite photocatalyst was successfully prepared by adding In₂O₃ to the precursor of Cu In S₂ and performing a hydrothermal reaction at 180°C.The composite of the two semiconductors was proved by systematic characterization,and the effects of different composite ratios on the activities of photocatalytic decomposition of aquatic hydrogen and reduction of Cr（VI）were studied.The results showed that the prepared Cu In S₂/In₂O₃ showed good absorption capacity in the wavelength range of 200-2200 nm,and the introduction of In₂O₃ significantly enhanced the photocatalytic activity of Cu In S2,and when the catalyst with an In₂O₃ content of 5wt.%had the highest activity,the hydrogen production rate reached 15.6 mmol h^-1 g^-1,which was attributed to the provision of a new photogenerated charge separation pathway.（2）In₂O₃/CaIn₂S₄ composite photocatalyst was prepared at 180°C by adding CaIn₂S₄ to the In₂O₃ precursor and adding reducing agent.The composite of the two semiconductors was demonstrated by systematic characterization,and the effects of different CaIn₂S₄ contents on the catalytic degradation of TC activity under UV,visible and near-infrared light of In₂O₃ were studied.The results showed that the introduction of CaIn₂S₄ enhanced the photocatalytic activity of In₂O₃ degradation of TC,and the catalytic activity was highest when the content of CaIn₂S₄ was 3wt.%,and the degradation rate about 88%lasts for 180 minutes after visible light exposure.