Photocatalytic Materials

Since the discovery of photocatalytic splitting of water on TiO 2 electrodes in 1972 by Honda and Fujishima, a great deal of effort has been devoted in recent years to the development of highly active heterogeneous photocatalysts for environmental applications including air purification, water disinfection, hazardous waste remediation, and water purification, as well as for the energy-related applications, such as, hydrogen production and solar cells.Among the various oxide and nonoxide semiconductor photocatalysts, the photocatalytic performance of titania has been most intensively studied because of its biological and chemical inertness, strong oxidizing power, cost effectiveness, and long-term stability against photocorrosion and chemical corrosion, and especially its energy band edges, which well match the redox potentials of water.However, the photocatalytic performance of TiO 2 must be further enhanced from the practical and commercial viewpoints, mainly due to the high recombination rate of photogenerated conduction band electrons and valence band holes and narrow light-response range resulting from the wide band gap.To resolve these problems, many methods have been proposed to enhance the photocatalytic activity of TiO 2 , including crystal and textural modification, band gap (electronic structure) engineering, interfacial heterostructuring, noble metal loading, metal ion doping, carbon and nitrogen doping, dye sensitization, and also the usage of sacrificial reagents (electron donors or hole scavengers).This special issue contains thirty nine papers, which mainly deal with environmental purification, hydrogen production, and dye-sensitized solar cells.Among them 30 papers are related to environmental photocatalysis, 4 papers deal with photoelectrocatalysis and photoelectrochemistry, 3