The Gel Route to TiO2 Photoanodes

Abstract

ABSTRACTCr3+ and Al3+ doped TiO2 can be easily made via the sol-gel process. Mixing the metal-organic solutions give rise to a random dispersion of the doping ions into the TiO2 network. Amorphous and crystalline phases have been characterized all the way from the gel to the crystalline products by thermal analysis, X-ray diffraction, vibrational spectroscopy and E.S.R. Organic groups appear to be involved in the formation of the gel network and could lead to a better control of the morphology of the xerogel. A thermal stabilization of the anatase phase, up to 900°C, is observed when Cr3+ is introduced as a dopant. This would lead to the preparation of anatase TiO2 photoanodes.