NEW IRON(III)-BASED VISIBLE LIGHT PHOTOCATALYSTS FOR WATER PURIFICATION

摘要

Current environmental issues such as the drinking water scarce are stimulating research to develop sustainable solutions for water purification. A photocatalytic approach is very attractive since solar energy is widely available at no cost. Upon illumination, photocatalysts absorb photons with an energy larger than their band gap. This photon energy is used to generate high-energy charge carriers, electron-hole pairs, which can drive redox reactions like the oxidation of organic pollutants. Much research has been focused on photocatalysts and photocatalytic processes using titanium dioxide (TiCh) since the landmark research of Fujishima and Honda in 1972 (Fu-jishima et al, 1972). However, despite being stable, reactive and low-cost, TiCte can only respond to ultraviolet (UV) light because of its large band gap (3.0 - 3.2 eV). This has stimulated photocatalytic research to develop new materials with a reduced band gap that can respond to the more abundant visible light photons.