Jorge Leonardo Cruz
Faculty Advisor: Yat Li
Research Supervisor: Edgar Collazo
CC Faculty Liaison: Sarah Gerhardt
Hydrogen is one of the most attractive and environmentally friendly alternatives to fossil fuels. Hydrogen generation through photoelectrochemical (PEC) water splitting using semiconductors as photoelectrodes represents a forefront in energy, science, and technology. The major challenge in developing an efficient metal oxide photoelectrode for PEC water oxidation is their low-lying valence bands. Bismuth Vanadate (BiVO4) is a direct band-gap semiconductor with a band-gap of 2.3-2.5 eV and its conduction band and band-edge have recently been determined to be +0.02 V and +2.53 V which should have a favorable band-gap for efficient visible light absorption and band-edges that could straddle the redox potentials of water photoelectrolysis. It has been predicted that a solar-to-hydrogen efficiency of ~10% can be achieved by a material with this band-gap. Bismuth (III) nitrate pentahydrate Bi(NO3)3 and Ammonium metavanadate NH4VO3 were mixed in an aqueous solution of nitric acid (HNO3) and then BiVO4 was synthesized onto an fluorine doped tin oxide (FTO) transparent substrate electrode. After the substrate dried at room temperature it was calcinated at 673K. The aim is to tune the band-edge position of BiVO4 by doping the BiVO4 substrate with transition metals to optimize the photoelectrode performance for PEC water oxidation.