| Energy are related to the human existence and development, so making use of solar energy has been one dream. Solar energy is an inexhaustible and non-polluting energy. From the space applications of solar cells in 1950's to today's solar optoelectronic integreated buildings, especially the past decade, the PV industry in the world keep high growth rate of 50%. Compared to silicon solar cells,dye-sensitized solar cell is a new type of low-cost solar cell based on nano-technology development in the recent 20 years. This kind of solar cell are known as the most promising solar cells.Especially for the country whose development of PV industry are relatively late, this new type of battery research and development is very important。As a wide band gap semiconductor with innocuity, stabilizaTiOn and cheapness, TiO2 is one of the best materials for preparing the anodes of DSSC. DSSC is a major part of the TiO2|dye| electrolyte sandwich structure.In this work, DSSCs were fabricted by dye-sensitized TiO2 thin films which had been deposited by dirrect current magnetron sputtering. The surface morphologies, crystal structure, optical characteristics and photoelectric conversion efficiency were characterized by atomic force microscopy (AFM), Raman spectrometer, UV-VIS spectrophotometer and solar detected instrment respectively. The effect of sputtering power, oxygen partial pressure and metal ion doping on photoelectric performance were studied.From the analysis of Raman spectra, transimission spectra and AFM images, It is shown that deposiTiOn rate reached the largest maximum while anatase phase started to be formed, at the same time, the target plane was sputtered in transformaTiOn pattern to a small extent of powers. With the increase of oxygen partial power, the surface morphology varied very little, which proved that the energy of sputtered particle had littlechange. With the increasing of the sputtering power and the doping of Al ions, The band gap reduced by doping with W in which exist lower conduTiOn band potential. However, doped with few Al contributed to the improvement of the surface morphologies and the blue shift of absopTiOn edge.It is observed in the adsorpTiOn spectra that the adsorpTiOn onto TiO2 increase owing to the thickening of TiO2 thin films as well as the reducing of Ti3+. From the analysis of the photovoltaic performance, we can conclute to that the formaTiOn of rutile phase is beneficial to the raising of filling factor(FF). With the increasing of sputtering powers, the short-circuit current(ISC) increased attributed to the thickening of the TiO2 thin films and the formaTiOn of anatase phase. The improvement of lattice defects and the doping of Al ions also enhanced the ISC. The Open-circuit voltage(VOC) is related to the potential of the conducTiOn band of TiO2, which influences the dark current. Therefore, the Voc decreased owing to the raising of dark current and the reducing of conducTiOn band potential in TiO2. The photoelectric conversion efficiency(η) determined by ISC, VOC and FF together reached the maximum 2.47% when prepared with sputtering power of Al-doped at 5 W, but decreased sharply when the TiO2 electrode had prepared with W-doped power at 15 W for introducing lower potential of conducTiOn band. |
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