Metal Oxides for Photoelectrochemical Water Splitting and Environmental Remediation

Metal oxide semiconductors play a central role as photoanodes for the photooxidation of water, thanks to the fulfillment of some fundamental requirements which include the absorption of near UV-Visible photons, the favorable position of their valence band edge with respect to the O2/H2O potential and stability in aqueous electrolytes under oxidizing conditions within appropriate pH intervals. The photoelectrochemical properties and the charge transfer dynamics of materials based on WO3 (both anodized and sol-gel), BiVO4 and Fe2O3 will be described in photoelectrochemical water splitting processes and in the OH radical mediated degradation of impervious emerging contaminants. The molecular sensitization of WO3 and SnO2 by cationic perylenes characterized by strongly oxidizing ground state redox potentials, aimed at the realization of molecular driven solar fuel production will also be considered.