Kinetics and Mechanism of Platinum Deposition by Photoelectrolysis in Illuminated Suspensions of Semiconducting Titanium Dioxide

Article abstract of DOI:10.1021/j100252a014

The rate of photoelectrochemical platinum metal deposition onto titanium dioxide particles in suspension in aqueous platinum hexachloride solutions illuminated by ultraviolet light has been studied quantitatively at different light intensities, salt concentrations, etc.It is proposed that the semiconductor particles are subject to strong internal electric fields which lead to efficient hole-electron-pair separation but that the titanium dioxide contains a large number of traps which cause recombination especially at high light intensities.The recombination is enhanced by the form adopted by the electrical field when several metal spots exist on the oxide grains, as has been observed.