Preparation And Photoinduction Properties Of Composite Spinel CuAl₂O₄Nanoparticles Of Doped Transition Metal

In this paper, transition metal-CuAl2O4composite spinel with narrowband gap were studied, especially the compound and the character under visible light induced, including the characteristics of photoinduced catalytic oxidation and photovoltaic characteristics. The details are as follows:The spinel-type Mo.2Cu0.8Al2O4(M=Ni, Zn, Co) compounds were prepared by sol-gel method, the synthesis conditions, structure, visible-light photocatalytic activities and relationship between the struture and performance of spinel compounds were investigated. The crystal structure was investigated by X-ray diffraction (XRD). And spectral response characteristics of spinel compounds were analyzed by infrared radiation (IR) and ultraviolet-visible diffuse reflectance spectra (UV-Vis). The results show that all the powders have spinel structure with particles sizes of several nanometers to several tens of nanometers, and their absorption band-edges are able to extend to the visible-light region in different degrees. The photocatalytic degradation experiments of Reactive brilliane red K-2G and acid red B are carried out in the suspension systems of spinels acting as photocatalysts. Among them, the nickel-doped CuAl2O4exhibites excellent visible light photocatalytic activity to acid red B and reactive brilliant red K-2G, the degradation rate of the dyes reached about90%in2h. The affecting the reaction conditions and the structure of dyes on photocatalytic efficiency were discussed.A series of NixCu1-xAl2O4(x=0;0.2;0.4;0.6;0.8;1.0) compounds were prepared via sol-gel method and their photocatalytic properties were studied under the visible light. The crystalline structure, morphology and spectral response of the prepared samples using analytic technologies such as XRD, transmission electron microscopy (TEM) and UV-Vis DRS are described. Using acid red B as model compound, the visible light photocatalytic activity of NixCu1-xAl2O4compounds was investigated. The relationships of the visible light irradiation time, or irradiation condition, the amount of the catalyst and the dye degradation rate were studied, and the stucture of the catalyst before and after degradation were analyzed by IR sbsorption spectra. The results show that different components of the catalyst with the different performance, the degradation of organic dye caused by catalyst visible light photocatalytic activity, and not by the surface adsorption.Ni0.4Cu0.6Al2O4/TiO2composite film electrode is prepared on ITO glass substrate by screen printing method, and the composite film and Pt electrode are used as light anode and counter electrode respectively, then the DSSC cell was assembled. The photoelectric properties of DSSC were researched. The influence of various doping (mass fraction:2%,4%,6%) on the photoelectric properties of Ni0.4Cu0.6Al2O4/TiO2composite film electrodes was investigated. Experimental results show that Ni0.4Cu0.6Al2O4can increase the electrode optical property, and different doping of composite film lead to different performance of membrance electrode. When the doping amount is4%, the photoelectricity properties is best, and thus the Isc is2.043mA, the Voc is0.74V and the FF is0.54, η is3.26%.