Local conductivity study of TiO2 electrodes by atomic force microscopy

Titanium dioxide (TiO2) nanocrystalline porous film electrodes were prepare d by the sol-gel method on indium-tin oxide (ITO) glass and chemically modi fied further by an aqueous solution of titanium tetrachloride for solar ene rgy conversion application. The surface topography and local conductivity o f the TiO2 films were investigated by atomic force microscopy and a simulta neous current mapping technique in the dark and under ultraviolet illuminat ion, respectively. It was found that the conductivity of the films was impr oved by chemical treatment and the possible mechanism of the effect was dis cussed. Copyright (C) 2001 John Wiley & Sons, Ltd.