Photoelectrochemical systems

Photoelectrochemical systems encompass numerous applications involving semiconductor/electrolyte interfaces. A major goal has been solar energy conversion. Double-digit efficiencies have been reached with two different forms of semiconductor/electrolyte photojunction, directly excited or dye sensitized. Impressive performance with even polycrystalline semiconductor substrates is attainable in these devices and makes them promising in photovoltaics and photoelectrosynthesis for efficiency and cost. Achieving improved stability and further advances in output and economics depends on further progress in understanding and modifying solid/liquid interfaces. Related developments have produced numerous spin-offs of substantial importance to solid-state devices, processing technology, and surface chemistry. Further progress toward significant applicants of interest to utility, electronics, and transportation industries in energy conversion, and toward a host of specialized opportunities from sophisticated etching of microstructures to water purification requires a serious effort to support and strengthen the fundamental underpinnings of the field. These needs are categorized in the conclusion of this overview.