| Abstract
| - Plasma-enhanced chemical vapor deposition (PECVD) was used in the preparation of aseries of bicomponent TiO2/SnO2 particulate films. The photocatalytic activities of the filmsare evaluated by photodegradation of phenol in solution. When both the TiO2 and SnO2components of the bicomponent TiO2/SnO2 catalysts are accessible to reactants at the catalystsurface, photocatalytic degradation efficiencies are improved as compared to those obtainedwith TiO2 films. When this condition prevails, the two components are believed to act in acooperative manner by increasing the degree of charge carrier separation sufficient to reducerecombination, while simultaneously allowing sufficient time for photoelectrons and photoholes on the catalyst surface to form reaction intermediates (for example, the superoxideradical ion, O2·-, formed by reaction of O2 with photoelectrons, and the phenol radical, formedby reaction of phenol with photoholes or OH· radicals) which cooperatively participate inlater stages of the degradation process.
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