Photochemistry at Hematite Surfaces for Production of Renewable Hydrogen
Industry consumes vast amounts of hydrogen, which is commonly produced by steam reforming of methane, in which natural gas or methane is reacted with water at high temperatures over a catalyst to yield carbon monoxide and hydrogen, followed by water-gas shift catalysis to produce carbon dioxide and additional hydrogen. In addition, small-scale steam methane reforming units are often discussed as distributed sources that could provide local supplies of hydrogen for fuel cells. Development of technology for generating renewable hydrogen from photocatalytic water splitting would contribute significantly to meeting the energy and self-sufficiency needs of the U.S., but progress is limited by the lack of efficient and cheap photocatalysts. We propose to address this limitation by developing the necessary fundamental understanding of the active sites and key intermediates responsible for redox reactions, and of the rate determining steps, which is needed to design and synthesize improved photocatalysts for hydrogen production. Our work will utilize atomic level surface characterization and in-situ studies of photochemical reactions in solution for hematite (Fe2O3) based materials, which have been shown to have promise as photocatalysts for water splitting. Advanced catalysts will enable significant reductions in CO2 emissions during hydrogen production and address a critical need for energy self-sufficiency by the production of renewable hydrogen.