Preparation Of Cu₂O/TiO₂ Nano-composite Thin Films For Photocatalytic Performance Study

With the rapid development of industry and technology,the energy crisis and environmental problems become exaggerate increasingly.Therefore,the use of clean energy solar power has became an effective way to solve these issues.Photocatalytic oxidation technology is particularly used to handle the complex components of organic wastewater,which is due to the unique characteristics of photocatalytic oxidation technology.However,there are some defects because the technology could not be industrialized.In this paper,the existence of the current solar pnotocatalytic powder utilization solved the low-efficiency and difficult-recovery issues.The prepared Cu₂O/TiO₂ thin film can be designed.The paper proposes an electrodeposition method to prepare Cu₂O/TiO₂ thin film and Cu₂O/TiO₂ thin film onto the ITO conducting glass.XRD、XPS、SEM、Raman、PL and UV-Vis are used to characterize and to analyze the thin film microstructure,surface morphology,banding state and optical properties respectively.The results are as follows:（1）Cu₂O/TiO₂/ITO nano-thin film is prepared onto ITO,the preparation conditions of Cu₂O thin film are investigated and the optimum conditions are as follows:the concentration of CuSO4 is 0.05mol/L,deposition current density is 0.12mA/cm2,the pH is 11.00,stirring rate is 100rpm and deposition time is 1.5h.The results indicate that the prepared Cu₂O/TiO₂ thin film with the preferential orientation of（111）showing high photocatalytic activity is of high-purity.The crystal structure of the sample exhibit high quality and nano regular octahedron morphology.Absorbing boundary of Cu₂O/TiO₂ thin film is at about 600nm,and the absorption peak increases rapidly between 350nm and 510nm.The absorbance intensity of Cu₂O/TiO₂ thin film is estimated to be 2.19 eV.（2）Influence factors such as annealing treatment and doping metal ion for morphology and properties of Cu₂O nano film are discussed.It is found that these factors all have obvious influences on the structure and properties of Cu₂O nano film.The 250℃ annealing treatment and doped Fe3+of Cu₂O/TiO₂ thin film can further enhance of（111）crystal plane intensity,UV-Vis absorption intensity respectively and absorption spectrum.Moreover,the open circuit potential up from around 13.5mV to 32.34mV.（3）The photocatalytic performance of Cu₂O is studied as well.Based on single factor experiment,response surface methodology is employed to optimize the main influences of photocatalytic degradation by Cu₂O/TiO₂ thin film,and the quadratic multinomial mathematical model is also established.Moreover,the degradation process and photocatalytic effect of phenol by Cu₂O are also studied.The results indicate that R2 in the established quadratic model is 0.9973 with better fitness and higher significance.The calculated value of degradation rate is very satisfied with data of experimentation,the relative error is found to be 0.15%.The quadratic model R2 for photocatalytic degradation of rhodamine B is 0.9818,with a good degree of fit and predictive.The experiments prove that a degradation rate is 98.4%under these conditions.The actual value and the predicted value of the relative error is 0.84%.