| Exploiting and researching photoelectric material is very important, becausebeing confronted with energy crisis now. Development of nano-scale thin film hadbecome popular topics of its research in photovoltaic field during the last years, incompany with electro-optical technique advancing in nano-scale thin film inch byinch. Manifold factor in configuration affect light-to-electric energy conversion ofnano-scale thin film, such as granular distribution, micropore size distribution,roughness, porosity, thickness of film, crystalline type and so on. Many scientistshad studied the effect between membrane structure and light-to-electric energyconversion of nano-scale thin film in the last years. C.J.Barbee had acquired TiO2porous membrane with different aperture by the aid of sol-gel method andhydrothermal method. They discovered that degree of roughness and amount ofporosity affect directly the dye absorption of thin film, besides there are samedegree of roughness and thickness, increasing of amount of porosity make TiO2content on unit area of the thin film, accordingly photoelectric current and light-to-electric energy conversion decline.Porous TiO2 thin films were prepared by sol-gel method using polyethyleneglycol (PEG) as the additive. To obtain different microstructure, different amountof PEG was adopted, to analyses altering of light-to-electric conversion of the thinfilm by changing size of aperture on the thin film. Moreover, studying the effectsof optical character and wetting ability of the thin film. It provided feasibletechnical method and experimental basis to improving of photoelectrictransformation efficiency of thin film.(1) Acquired porous nano-scale thin films by sol-gel method usingpolyethylene glycol (PEG) as the additive. It is discovered that the nanoscalemicrostructure of the TiO2 thin film is influenced with changing the addition ofPEG. The thickness of 70 nanometre and pore deepness of about 50~60 nanometreon thin films tested by atomic force microscopy, so it can be thought of single-layerfilm. Otherwise crystalline type of the thin film was anatase and ruthile by XRD,but anatase was dominant. Content of the film can be approved by XPS.(2) Further conformed wetting ability of the porous thin film, having thecompletely spreading time of 780~890 millisecond. This is faster than that ofaporate thin film, moreover wetting ability of the thin film is alterant with changingpore size of the thin film, e.g. the thin film with 500 micromillimeter aperture is thefastest completely wettability, about 780 ms. Secondly is the thin film with 250 nmaperture. In addition, make aporate thin film photophobic deposited for threemonths, wettability of the thin film occur to evidence transformation, from 1400millisecond completely wettability to contact angle with 27.5°. But for porous thinfilm, make them photophobic deposited in the same time, and contact angle of thethin film can not evidence distinguish. The results obtained showed that enduringwettability of thin film can be improved by changing surface structure of TiO2 thinfilm.(3) Studied light-to-electric energy conversion of the nano-porous TiO2 thinfilm, and obtained light-to electric curve. From this curve, we become consciousthat thin film with porous size of 250 nm is strongest in photoelectricity conversion.So we can discover that the connection is not simply direct proportion betweenporous size and photoelectricity conversion of the thin film. We can obtain the bestphotoelectricity conversion by adjusting porous size on thin film.(4) Spectrum properties of the thin film are analyzed. Transparency of porousthin film is better than aporate thin film near to visible light region, moreover thetransparency change along with changing of porous size. Studying the absorptionspectrum properties of thin film, absorption peak is the highest for the 250 nmporous thin film. This result is agreement with experimental result ofphotoelectricity conversion. At last, in infrared region we find out the lowerreflection properties of these thin films, e.g. the thin film of porous size 250 nm isprominence. So we can select the best capability in transparency, absorption andanti-reflection properties by controlling porous size of thin film. Sequentiallyapplication field is developed using these thin films. The material withphotoelectricity conversion characteristic is improved.
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