| Nanosized TiO2 particles which were used in preparation of nanocrystalline TiO2 films were prepared by sol-gel method. The sol was obtained by using TEOT as hydrolysis precursor, C2H5OH or HNO3 as solvent. The physical and chemical changes during the sol-gel process were analyzed and the condition for the formation of sol-gel was improved. The effects of processing parameters on the crystalline phases, particle size and BET area of nano-TiO2 powders were discussed. TiO2 nanoporous films were made on ITO glass with sol-gel method and powder spreading method, then were sensitized in eosine solution. The effects of processing parameters on the properties of thin film, open-circuit voltage and short-circuit current of the assembled solar cells were studied. Besides, the concentration of dye solution, dye-sensitized temperature and dye-sensitized time were confirmed.TiO2 powders'characteristics influenced by the calcining temperature and time of heat preservation. During the process of calcining, the anatase crystallites was formed first, and it transformed to rutile crystallites at about 500℃and completed at 700℃. TiO2 powders with 1215 nm particle size and about 100m2/g, which endues the prepared films with excellent photo-electro-chemical properties can be obtained at 500℃.Experimental results show that the properties of TiO2 films, the concentration of dye solution, dye-sensitized temperature and dye-sensitized time have great effects on the quantity of cells. The films with the thickness of 1015μm used in the cells were prepared by using 1215 nm particle size, anatase TiO2 powders, TiO2 sol as the slurry solvent can tightly united with the substrate, and have good performance. From the experiment the optimized sensitized condition were 0.5g/L dye solution, sensitized for 3040mins at 50℃. With the optimized film characteristics and cells'processing conditions, the highest open-circuit voltage of 0.55V and short-circuit current of 0.80mA have been obtained.
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