Preparation And Property Study Of CdS-based Photocatalysts

Photocatalytic technology has great research prospects and application value in the degradation of organic pollutants.As a semiconductor photocatalyst,cadmium sulfide(CdS)has received extensive attention due to its suitable band gap(2.4 eV)and high photocatalytic activity.However,its shortcomings of photocorrosion and photogenerated electron-hole recombination are hindering its application in the field of photocatalysis.In response to this problem,this paper carried out research to improve the photocatalytic properties of CdS.The crystal structure,morphology,electrical properties and photocatalytic properties of the catalysts were investigated by XRD,SEM,TEM,XPS,BET,Tafel and other photocatalytic properties.The main research contents and results are as follows.(1)Two different morphologies of CdS/BiVO4 composite photocatalysts were prepared by simple coprecipitation method,and Rhodamine B(RhB)was used to evaluate the photocatalytic activity.The photocatalytic test results show that the composite photocatalysts of both shapes have the maximum catalytic effect when the content of CdS is 60%.Compared with BCS-60,BAC-60 has a 1.5 times increase in photocatalytic activity for RhB photodegradation.Electrochemical test results show that BAC-60 will have different internal electron flow directions due to different light and matte conditions.(2)CdS/C3N4 composite photocatalysts were prepared by simple co-precipitation method,and Rhodamine B(RhB)was used to evaluate the photocatalytic activity.The photocatalytic test results show that the composite photocatalyst containing 20%CdS has the highest photocatalytic activity.The effects of different temperatures on the performance of 20%CdS/C3N4(CS-20)were investigated by heat treatment.The photocatalytic test results show that 300℃ is the optimum heat treatment temperature.(3)BiOBr/CdS composite photocatalysts were prepared by simple precipitation method,and Rhodamine B(RhB)was used to evaluate the photocatalytic activity of each.The photocatalytic test results show that the composite photocatalyst containing 40%CdS has the highest photocatalytic activity.