All fuel-forming reactions and catalysis involve moving electrons from one species to another, a.k.a. redox chemistry (combination of “reduction” and “oxidation”). In order to store the energy from the sun in the form of fuels, researchers will need a clean source of electrons. Nature’s source of electrons in photosynthesis comes from water. By converting water molecules into their constituent oxygen gas and positive hydrogen ions, electrons can be derived (oxidation). This process, however, is very strenuous, and special substances— catalysts— are needed to facilitate that reaction. SOFI researchers are developing new catalysts that use earth-abundant elements to split water, either by an electrical potential or by a light-driven process.