Preparation And Photocalytic Behavior Of TiO₂Film Doped With Cual₂O₄

The photo-degradation of pollutants by using semiconductor material becomes importantinvestigation task recently. It has the academic significance and applied worthiness. Amongall photocatalyst, TiO₂has been used widely to deal with the wastewater, to decontaminate theair, to sterilize and to clean the glass itself because of its steady chemical characteristic,non-toxicity and low cost. But there are two difficult problems, one is that TiO₂with wideband gap is merely responded in ultraviolet spectrum, the other is that the photo-generationelectron-hole is composite ineffectively. The people bend themselves to settle those problems.The TiO₂composite with narrow band gap semiconductor is a method of modified TiO₂toextent the light response range. CuAl₂O₄is a new type visible light response photocatalyst.According to the mechanism of semiconductor compositeness, it is expected that theabsorbance edge of CuAl₂O₄doped TiO₂thin film shifts to visible light section.In this work, CuAl₂O₄doped TiO₂nanometer film on glass substract was prepared by thesol-gel method. The crystal structure and the surface morphology of film were studied byXRD and TEM. The spectral response was researched by UV-vis DRS. The hydrophilecapability was mensurated by using the contact angle meter. The COD value of the dyesolution was set out by utilizing titration method of potassium dichromate. The photocatalyticactivity of modified TiO₂thin film was studied by changing CuAl₂O₄doped amount,illumination time and thickness of plated film. The absorbance of the initial and afterphotodegradation of acid red B solution was measured by using UV-vis spectrophotometer.According to the data, the photodegradation rate of acid red B solution by TiO₂compoundthin film were calculated.The results indicate that the absorption edged wavelength of TiO₂mulriple film dopedwith CuAl₂O₄（0.5、1、1.5、2.5、3mol﹪） is among410-420nm, its absorption range expandedto visible light section obviously. Specially the absorption edged of the mulriple film dopedwith CuAl₂O₄in2mol﹪can come to450nm, which is larger75nm than the absorption edgedof pure TiO₂film. Of all the CuAl₂O₄doped amount, the degradation effect of acid red B onthe films is best when the doped quantity of CuAl₂O₄is2mol﹪. The discolored rate and the COD removed rate is67.3﹪and47﹪, respectively. The mineralization effect of dye solutionis perfect. The wettability of films is favorable, and it can use time after time.