Studies On The Preparation And Properties Of TiO₂-Cu₂O Nano Composite Film And Its Application

Nano titanium dioxide(TiO₂) is a kind of n-type semiconductor material with larger band gap, which only to be stimulated by UV light that reduced the utilization of solar energy, and because of the high rate of the recombination of the excited electrons and holes, it reduce the efficiency of the TiO₂ photocatalysis; Nano cuprous oxide(Cu₂O) is a kind of p-type semiconductor material with the band gap of 2.17eV, has been considered to be one of the attractive materials for solar cells for a long time. Cuprous oxide has the prominent advantages of high-absorption coefficiency in the visible region, non-toxicity,abundant,availability and low-coat producibility. However the problem is that single Cu₂O is very lively, which can be oxidated easily. But it has been reported that TiO₂-Cu₂O heterojunction electrodes prepared by electrochemical methods is very steady,and also found that when they were composited, it was not only enhance the efficiency of using the visible light, but also increase the stability of Cu₂O.In this paper, we mainly introduce the preparation of TiO₂ film by sol-gel method on the slide basement through dipcoating,then we got the nano composited TiO₂-Cu₂O film by chemical deposition. We characterized these samples by SEM, TEM, HRTEM and found that these particles composited of the film are about 10nm and the "blue shift" phenomenon of UV-Vis absorbing spectrum proved the composited film has the Quantum Size Effect. According to the XRD and XPS studies, we find that the nano-composite film is stable after being measured a year later, there was still no other valence of copper except for the cuprous oxide, that proved the good stability of the cuprous oxide in this film. We tested the transmission of TiO₂-Cu₂O and TiO₂ film, it also showed that the composited films had absorbed about 60% ultraviolet radiation and almost all of the near ultraviolet radiation while the transmission was improved during the visible light compared to the TiO₂ film. Then the fluorescence properties of the composited films were investigated by the fluorometry at different excitated wavelength according to this phenomenon. The study on its fluorescence properties indicated that there were five obvious emission peaks at 369,450,470,480 and 495nm, and 270nm is the best excited wavelength. Studies on the properties of the composited film,which provided important evidence of developing and empoldering new-style nano-sized photovoltaic materials. According to a special optical properties of nano-composite TiO₂-Cu₂O film,we applied the technique in preparing lamp-shade to avoid insects. By the experiment in laboratory and outdoor lawn, the effect of this new type lamp-shade on outdoor lighting to prevent insects is very good and it has a highe value in application.