SEM and RHEED-REM Study of Au Particles Deposited on Rutile TiO_2(110) by Deposition Precipitation and Gas-Phase Grafting Methods

摘要

In order to investigate the structural features of Au/TiO_2 catalysts, which are active for the low-temperature oxidation of CO and reverse water shift reaction, a model structure was prepared by deposition precipitation (DP) and gas-phase grafting (GG) methods using rutile TiO_2 single-crystal fragments with cleaved (110) faces. SEM (scanning electron microscope) and RHEED-REM (reflection high-energy electron diffraction-reflection electron microscope) observations proved that Au particles deposited by DP are nonomogeneously dispersed while those by GG are homogeneously dispersed on the (110) surface of the rutile TiO_2. the RHEED pattern indicated that a preferred orientation between the Au particles and the TiO_2(110) was [110](111)_(Au)//[001](110)_(TiO_2) for both preparation cases.