A comparative study was conducted on the interaction of Pt with the (1x1) and (1x2) surface phases of rutile TiO2(110). It was found that the surface structure and stoichiometry of TiO2 have profound effects on the formation and growth of nano-sized Pt clusters on TiO2(110). On the (1x1) surface, Pt formed randomly-distributed, three-dimensional nanoclusters that coalesced and were encapsulated when thermally annealed. In contrast, smaller Pt clusters were identified to adsorb on top of the titanium atomic rows on the (1x2) surface and exhibited higher thermal stability. The stronger interaciton observed for the Pt on the (1x2) surface is due to a charge transfer from Ti to Pt atoms. Vicinal TiO2(110) surfaces with alternating (1x1) and (1x2) domains were used to verify the different interactions of Pt for the two domains. Upon Pt deposition, an array of self-organized Pt nanoclusters was formed on this suface. The self-organization is due to different interactions of Pt with the two different surface domains and preferential diffusion of Pt nanoclusters along the titanium atomic rows on the (1x2) surface.
Revised: January 12, 2012 |
Published: March 10, 2001
Citation
Gan S., Y. Liang, and D.R. Baer. 2001.Effects of titania surface structure on the nucleation and growth of Pt nanoclusters on rutile TiO2(110).Surface Science 475, no. 1-3:159-170.PNNL-SA-33811.