Study On The Kinetic Behavior Of Modified Semiconductor Electrode Catalytic Oxidation

At present,the energy problem is becoming more and more serious.The efficient utilization of solar energy by catalytic reactions with semiconductor materials has attracted much attention.Semiconductor materials can produce electron-hole pairs when it is exciting,which has the ability of oxidable and has great significance in the fields of photoelectrochemical water splitting and photocatalytic organic synthesis.However,the pure semiconductor catalytic materials usually have poor catalytic effect and need to be modified.α-Fe₂O₃ is considered to be an ideal photoanode material.However,part of photoexcitation charge carriers may recombine during their transport process,which results inα-Fe₂O₃ performs not well in practical applications;Metal halide perovskites are regarded as a new promising kind of semiconductor,which has great potential application value of photocatalytic reaction.In this study,α-Fe₂O₃ and metal halide perovskite are used as research objects to study the effects of doping and surface modification on the catalytic oxidation of semiconductors.（1）Two kinds of precursors were prepared by hydrothermal method,which was respectively modified by Sn element doping and Ti O₂ loading,and the phase change and atomic recombination ofα-Fe OOH during heat treatment,Sn is better doped intoα-Fe₂O₃,and the combination ofα-Fe₂O₃ nanorod surface and Ti O₂ greatly improves its photoelectrochemical performance.It is found thatα-Fe OOH is a better precursor in the modification ofα-Fe₂O₃ photoelectrode.（2）Base on the previous section,selecting a suitable precursor for modification,which is research by test and materials studio calculation.The result shows that sample20-FST-5 is the largest photocurrent and the photoelectrochemical performance is promote greatly,which reach to 1.657 m A·cm^-2.DFT calculations Indicate the heterojunction between Ti O₂ andα-Fe₂O₃ is successfully constructed,and Fe atom is regarded as the active center of oxidation reaction.（3）We synthesize Cs PbBr₃/Cs₄PbBr₆ nanosheets as a visible-light photocatalyst for the oxidation of styrene to benzaldehyde at room temperature using oxygen as the oxidant.Using Zr Cl₄ in modifying Cs PbBr₃/Cs₄PbBr₆ nanosheets to enhance the oxidation ability and promote the transfer of carriers,the catalytic rate of CPB-Zr-0.75is 1098μmol/（g·h）,.In addition,the mechanism of the enhanced photocatalytic performance from Zr Cl₄-Cs PbBr₃/Cs₄PbBr₆ nanosheets toward the oxidation of styrene is reasonably proposed.