Preparation And Photoelectrochemical Properties Of CuFeO₂ Nanomaterials And Their Heterojunctions

CuFeO2 as a typical p type semiconductor,with 1.5 eV band gap.The composition of its copper and iron reserves,has a wealth of the earth and its preparation is simple,with better light absorption performance and stability etc.Advantage,because the body of light raw material easily happened charge in combination with surface recombination,photoproduction carrier separation efficiency is low,to a large extent hindered the photoelectricity chemistry of its practical application.CuFeO2 nanosheets were prepared and CuFeO2/ZnO heterostructure was constructed to solve the photocharge composite of CuFeO2 materials.The main work of this article is as follows:(1)The effect of hydrothermal reaction conditions on the morphology and photoelectrochemical performance of CuFeO2 was studied.The results show that CuFeO2 prepared by sulfate system under high concentration of NaOH has strong corrosion resistance,good photoelectrochemical performance and uniform morphology structure And other advantages.(2)The CuFeO2 nanosheet with thickness of about 40 nm was successfully synthesized by introducing sodium alginate(SA)as a soft template agent in order to inhibit the bulk composite of the material.When the electric potential was-0.3 V,the light response current of CuFeO2 nanosheet was 19.28 ?A cm.2,compared with the light response current value of the raw material 8.88 ?A·cm-2.Through the analysis of open circuit potential diagram,CuFeO2 nanosheet structure has a shorter photogenic carrier transport path,which can effectively inhibit the occurrence of photogenic charge recombination.However,this structure can easily lead to the accumulation of photogenic charge and surface recombination at the two-phase interface.(3)in order to further optimize the performance of CuFeO2 nanosheets and solve the problem of extremely fast attenuation rate of photogenerated charge on the surface of CuFeO2 nanosheets,CuFeO2/ZnO heterojunction structure was constructed to further utilize photogenerated charge on the surface of the nanosheets.ZnO seeds were grown on the surface epitaxy by one-step atmospheric hydrothermal method.Then the secondary water heat of the original precursor suspension was applied to control the length of ZnO,namely the mass ratio of ZnO in the heterojunction structure,by regulating the reaction time.There is a self-built electric field at the interface where the two materials contact to promote charge separation and at the same time promote charge transmission.The different amount of ZnO makes the photogenerated charge separation direction of the heterojunction structure different.Photocatalytic reduction of benzaldehyde generates benzylalcohol.