Abstract: The surface topography and structure of platinum loaded on TiO2 fiber were investigated by atomic force microscopy. The micron-sized platinum domains were rectangle-like on the TiO2 fiber with low content of Pt but were hexagon-like on the TiO2 fiber with high content of Pt. The topography of Pt domains on TiO2 fiber was similar to Pt nanocluster on TiO2 (110), but the size of Pt domains was obviously larger. The specific topography of Pt domains and the ordered distribution of nano-crystals of TiO2 fiber implied that there was a strong metal-support interaction between Pt and TiO2 fiber. There were many terraces on the Pt domains, and the height of terraces mainly ranged from two to four times the interplanar distance of Pt (111). Moreover, the specific surface area of Pt/TiO2 fiber was almost unchanged before and after the loading of Pt. The strong metal-support interaction and the terrace structure of Pt might be the reasons that the photocatalytic activity of Pt/TiO2 fiber was high although the Pt was micron-sized domains.

Key words: platinum, titanium oxide fiber, atomic force microscopy, photocatalysis, surface terrace