Research: Solar Fuels
Earth-abundant semiconductors capable of directly converting sunlight into fuels may provide a singular solution to solar energy conversion and energy storage. Fuels are a particularly attractive form in which to store renewable energy owing to the high energy density and portability of chemical bonds. Argonne researchers, working with collaborators at Michigan State University, have shown that the efficiency of water splitting with hematite - the most prevalent iron oxide in rust - is dramatically enhanced by additional of an ultra-thin cobalt-based coating. Atomic layer deposition was employed to grow a cobalt oxide film of less than one atomic layer that is transparent, stable, and capable of accelerating the rate at which O2 is generated at the semiconductor/water interface. When viewed as a general approach to accelerating the photoelectrochemical conversion of sunlight to fuels this methods paves the way for improvement of a wide variety of catalytically-limited solar fuels reactions.