Synthesis of TiO2/ITO nanostructure photoelectrodes and their application for dye-sensitized solar cells

Abstract

A Sn-doped In2O3 (ITO) nanowire photoelectrode was produced using a simple metal evaporation method at low synthesis temperature (<540°C). The nanowire electrodes have large surface area compared with that of flat ITO thin film, and show low electrical resistivity of 5.6×10-3Ωcm at room temperature. In order to apply ITO nanowires to the photoelectrodes of dye-sensitized solar cell (DSSC), those surfaces were modified by TiO2 nanoparticles using a chemical bath deposition (CBD) method. The conversion efficiency of the fabricated TiO 2/ITO nanostructure-based DSSC was obtained at 1.4%, which was increased value by a factor of 6 than one without ITO nanowires photoelectrode. This result is attributed to the large surface area and superior electrical property of the ITO nanowires photoelectrode, as well as the structural advantages, including short diffusion length of photo-induced electrons, of the fabricated TiO2/ITO nanostructure-based DSSC.