Electron Transport in the Nanostructured TiO₂−Electrolyte System Studied with Time-Resolved Photocurrents

Abstract

Laser flash induced photocurrent transient measurements have been used to investigate the electron transport in nanostructured TiO2 (anatase) thin film electrodes in contact with an electrolyte. The shape and the time domain for the current transients were found to be dependent on film thickness and electrolyte conductivity. The experimental results are discussed using a diffusion model. If the experimental results are interpreted as diffusion, a chemical diffusion coefficient for the electrons in the nanostructured system is determined to 1.5 × 10-5 cm2/s using 700 mM LiClO4 in ethanol as electrolyte.