| Abstract
| - Supported metal catalysts have been used extensively in many current industrial processes. Themorphology of coated metal on a support is usually an important factor affecting the efficiency of thecatalyst. In this study, the investigation is focused on a photocatalytic process to coat silver clusters ontitania (P-25 TiO2) with an emphasis on the morphology control of coated silver clusters. For the first time,the particle size and the deployment intervals of silver clusters are controlled with an innovative methodthat involves the in-situ formation of water-insoluble transitory species such as AgBr, AgCl, or Ag2O onthe surface of titanium dioxide. Experimental results demonstrated that the transitory particles functionas physical spacers, which temporarily occupy some of the active site on the titanium dioxide surface andact as reservoirs for Ag+ ions to keep the local Ag+ concentration on TiO2 extremely low. The silver clusterscoated on titania are found to be stable in the spherical silver-3c syn crystalline form indicated by TEM,XRD, and XPS measurements.
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