Oxidation Of 5-HMF Coupled With Hydrogen Production From Water Spltting Photo-catalyzed By Cadmium Sulfide Composite

With the continuous development of industry and the continuous consumption of fossil fuels,the demand for petroleum derived chemicals is increasing.It is of great significance to develop other resources to replace industry’s dependence on petroleum.5-hydroxymethylfurfural（HMF）is a biomass based platform molecule,which can be derived into many important chemical molecules.However,the traditional catalytic HMF method will consume a large amount of resources and energy,so it is important use the clean catalytic method.In this paper,CdS/MoS₂ with one-dimensional nanorod structure was synthesized by one-step solvothermal method and applied to photocatalytic oxidation of HMF to DFF.The results show that CdS/MoS₂-10 has the best catalytic performance for HMF oxidation.In the CdS/MoS₂-10 photocatalytic experiment,the conversion of HMF and the selectivity of DFF increased continuously,and the selectivity of DFF reached 87.5%and the conversion of HMF reached 28.8%in 2 h.The over active species detection experiment showed that the hole was the active group of photocatalytic oxidation of HMF.Due to the MoS₂ is an excellent electron acceptor,the photogenerated electrons on CdS migrate to MoS₂,which improves the electron hole separation ability of CdS/MoS₂.Subsequently,PL characterization,transient photocurrent was used to verify that CdS/MoS₂ nanorods have stronger charge separation ability and transport ability.In order to improve the photocatalytic performance of HMF,the template method and ion exchange method were used to construct one-dimensional structure ZnS@CdS/Ni nanotubes.It is used to replace CdS nanorods.Through the ZnS@CdS/Ni optimize experiment to prove ZnS@CdS/Ni-30 has the best catalytic performance for HMF oxidation.The study found that,ZnS@CdS/Ni-30 during the photocatalytic oxidation of HMF,the conversion of HMF increased,and the selectivity of DFF increased first and then decreased.The conversion of HMF is 36%,and the selectivity of DFF is 99.1%.ZnS@CdS/Ni-30 the catalytic performance of HMF is better than that of CdS/MoS₂ in terms of reaction time,conversion of HMF and selectivity of DFF.In addition,the active species of HMF oxidation on the surface of subsequent experiments were holes.Through analysis ZnS@CdS/Ni the energy band structure shows that the photogenerated electrons of CdS are transferred to the outer Ni and the holes are transferred to the inner defect ZnS of ZnS@CdS/Ni and the space charge separation structure is formed.PL characterization,transient photocurrent and electrochemical impedance were used to verify the results ZnS@CdS/Ni space charge separation has excellent properties of charge transfer and separation.