Preparation of TiNxO2-x Photoelectrodes with NH3 Under Controllable Middle Pressures for Dye-Sensitized Solar Cells

As part of our efforts to find a way to control the concentration of N-doped TiO2, TiNxO2-x powders were prepared by a device of our own design. In this research, photoelectrodes are generated using N-doped TiO2 materials where the concentrations are adjusted by the amount of NH3 under middle pressure, which is seldom reported. Considerable efforts have been directed to the study of the optical absorption edge that is redshifted towards the visible-light region. Therefore, N-doped TiO2 electrodes are characterized by SPS and TPV analyses as experimental and theoretical studies. Experimental results indicate that the band gap of the semiconductor has been narrowed by increasing the concentration of the N-doped TiO2. The overall conversion efficiency of the solar cell has shown that the photoelectrical properties of the N-doped TiO2 have greatly improved with different concentrations. It can therefore be concluded that the synthesis route we found through this study is an effective way to adjust the relationship between the concentration and the band gap of the N-doped TiO2 photoelectrodes. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)