Preparation And Performance Study Of Transition Metal Sulfide-based Composite Photocatalysts With Broad Spectrum Response

Because of their own band gap characteristics,transition metal sulfides have better broad-spectrum response as photocatalytic materials than other materials.In addition,transition metal sulfides have great research and application prospects in the fields of electricity,optics,magnetism and medicine.At the same time,exploring transition metal sulfides as photocatalytic materials is also one of the most important topics in the field of energy and environment.Based on this,the transition metal sulfide and its composites were systematically prepared,characterized,and their photocatalytic properties were studied.The main contents are as following:We,herein,report the synthesis of umbrella-like CdS single crystal with exposed high activity?002?facets first time by using a one-step hydrothermal method with cadmium acetate dihydrate?Cd?CH₃COO?₂·2H₂O?and ammonium thiocyanate?NH4SCN?,and its possible growth mechanism was discussed.As a contrast,CdS nanoparticles with different morphologies were also synthesized.The morphology,composition and photocatalytic property of as-synthesized samples were determined by XRD,SEM,TEM,UV-Vis DRS,PL and photocurrent tests,respectively.The results show that umbrella-like Cd S under UV?20 min?and visible light?80 min?irradiation,the removal rate of rhodamine B was as high as 99.1 % and 99.3 %,respectively.Moreover,even though the particle size of umbrellalike Cd S particle larger than as-synthesized Cd S nanospheres,it still shows excellent photocatalytic degradation activity due to its exposed high-energy?002?facets.And its excellent application prospects are conceivable.The current work provides a new paradigm in material morphology design,especially in the construction of highly active surfaces for photocatalysis and photoelectric conversion.In addition,in this paper,zinc sulfide?ZnS?,copper sulfide?Cu S?,and silver sulfide?Ag₂S?were synthesized by a one-step hydrothermal method.In view of the rapid reorganization of photo-generated electron-hole pairs in photocatalytic materials and the limited range of light absorption of photocatalytic materials,the materials were subjected to composite treatment to further synthesize molybdenum disulfide?MoS₂?,titanium dioxide?TiO₂?nanobelts and indium sulfide?In₂S₃?,and Zn S /Mo S₂,Zn S / TiO₂ nanobelts,Cu S / In₂S₃ composite photocatalytic materials.The results show that the prepared materials all have excellent photocatalytic performance,especially the photocatalytic performance of ZnS and TiO₂ nanoribbons is significantly improved.This is because the Zn S grows uniformly on the surface of the TiO₂ nanoribbons,formed the heterostructure,the existence of heterojunction inhibits the recombination of photogenerated electron-hole pairs.In summary,the umbrella-like CdS with novel morphology prepared in this paper has more excellent photoelectric activity and photocatalytic degradation ability than common CdS nanospheres,which is due to the exposure of high active surface?002?crystal surface caused by its regular morphology.After composite treatment of ZnS,CuS and other materials,ZnS / TiO₂ nanobelts and Cu S / In₂S₃ composite photocatalysis materials have excellent photocatalytic degradation activity.The above research content provides new ideas for the design of transition metal sulfides and their composite materials,and is of great significance for the study of improving the performance of transition metal sulfidebased photocatalysts.