INTERFACIAL CHEMISTRY OF III-V SEMICONDUCTORS FOR PHOTOELECTROCHEMICAL WATER SPLITTING

摘要

Photoelectrochemical (PEC) production of H2 fuel from water and sunlight is a promising long-term, sustainable energy solution.1 However, intensive screening has failed to discover an electrode material that meets targets for both efficiency and durability. The design difficulty arises from the materials requirements that must be simultaneously met, including efficiency of photon harvesting, as well as favorable thermodynamics and reaction kinetics for photolysis. At present, the most efficient devices are based on III-V semiconductors. For example, tandem devices based on a GaInP2 photocathode have demonstrated solar-to-hydrogen conversion efficiencies in excess of 12%.2 However, these devices exhibit rapid photocorrosion in aqueous environments, limiting their practicality.3,4