Preparation of TiN_xO_2–x Photoelectrodes with NH₃ Under Controllable Middle Pressures for Dye‐Sensitized Solar Cells

Abstract

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.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Study on Strategy to Incorporate Carbon and Nitrogen in Nanostructured TiO2: Modification of Low Bandgap Initiated by Broad Spectrum Response and Its Photoelectrochemical Properties

“…With bandgap modification, Khan et al [3] demonstrated a lower bandgap energy (2.32 eV) of carbon doped n-TiO 2−x C x type film synthesized by combustion of the Ti metal sheet, which absorbed light at wavelengths below 535 nm. Band-gap narrowing was also observed in nitrogen doped TiO 2 nanoparticles and the results obtained from the density functional theory (DFT) calculations shows that N-doped TiO 2 could achieve the absorption spectra broadened owing to the presence of N-impurities [4][5][6][7][8].…”

TiOx/Ny nanowire arrays: NH3-assisted controllable vertical oriented growth and the electrophotochemical properties

“…Secondly, the sintered films were put in a sealed stainless steel autoclave designed by ourselves (see Supporting information) and treated in NH3 with pressures ranging from 0 to 0.8 MPa (0, 0.2, 0.6, and 0.8 MPa) at 400 • C for 12 h. The NH3 gas with 99% purity was first purified via a device that absorbed impurities and then flowed into the reaction chamber. The heater power was not launched until the NH3 pressure reached the predetermined value [19].…”

Performance of Dye‐Sensitized Solar Cells Based on MWCNT/TiO2–xNx Nanocomposite Electrodes

“…[20] An enhanced photocurrent and retarded electron recombination has been observed in DSCs. [21][22][23] Therefore, we attempted to use MWCNT/ TiO 2-x N x nanocomposites as photoelectrodes to enhance electron transfer and collection, which can further improve the photovoltaic performance of DSCs.…”