Incorporation of indium in TiO2-based photoanodes for enhancing the photovoltaic conversion efficiency of dye-sensitized solar cells

Abstract

Sol–gel-assisted spin-coating method was used to prepare TiO2 photoelectrodes doped with four different concentrations of indium 0.025, 0.05, 0.075 and 0.1 M. The crystalline phase and average crystallite size of the pure- and indium-doped TiO2 films were found using X-ray diffractometer. Raman analysis was performed for the pure- and In-doped TiO2 films to confirm the structure of anatase phase. UV–visible and photoluminescence spectrophotometer were used to analyze the optical properties of the films. A shift towards a lower wavelength in the absorption spectrum and widening of band gap were noted for the doped TiO2 films. Reduction in the peak intensity was observed in the PL spectra to indicate the inhibiting action of electron–hole recombination. A maximum (2.71%) light to current efficiency is noted for the dye-sensitized solar cells (DSSC) fabricated based on 0.025M In-doped TiO2 electrode.