Dye-sensitized Titanium Dioxide Thin-film Electrodes Preparation And Optical Performance

It is thought that dye-sensitized nanocrystalline solar cell(DSC) is a new type of photoelectric chemical solar cell with simple preparation procedure, low cost, stable photo-toelectric and friendly environment action, which make it a good alternative of photo-to-electric devices;in addition there is very important significance. In this paper, pureTiO₂ and doped TiO₂ thin film electrodes were studied. The crystalline structure and crystallographic orientation of TiO₂ films were measured by a Y-2000 X-ray diffractometer (XRD). The surface morphology of TiO₂ films has been observed by Scan Electron Microscope (SEM). The UV-VIS spectra of TiO₂ films on fused glass substrate was measured in air at room temperature using a Shimadzu UV-2550 spectrophotometer in the range from 300nm to 800 nm. phase transition was observed by DSC-TGA. TiO₂ thin film electrodes were sensitized by natural dye. The photoelectric properties of them were tested and the best photoelectricity percent conversion was 1.01 %.Orthogonal test was adopted to optimize technology parameters in this paper. By the test result, when Butyl tianate ,ethanol, de-ionized water diethanolamine's mixture tatio was 70 : 12 : 1 : 4, TiO₂ thin film electrode had the best photoelectric properties. The experiment shows that the crystal structure of the pure TiO₂ film was anatase model, and preferred orientation on (101) crystal face. During the process of the thin film electrode preparation, accrescence of acid had no effects to TioO₂ crystal structure.The main influencing factors to TiC>2 electrode such as annealing temperature, soaking time, PEG( Polyethylene glycol), accelerating agent(acid) were detail studied. The microstructure of titania films could be modulated by the amount of PEG and treating temperature;at the same time, the porosity of the films improved with the increase of PEG.The V_oc and the Isc of the best electrodes were separately 596mVand 301uA.The photoelectricity percent conversion was 0.89%.Oxide diffraction peek of metal ion doped TIO2 films were not found in XRD patterns and the phase changing temperature was lowed from DSC-TGA curves analyses. Cu2+ doped TiO2 thin film had map cracking,the others were smooth and flat. Zn2+doped TiO2 thin film electrode improved the photoelectric properties;The Vqc and the IscOf the best electrode were separately 702mV and 417uA;The photoelectricity percent conversion was 1.01%.