[21p-C106-1~11] 6.5 Surface Physics, Vacuum

[21p-C106-10] Investigation of the interaction between Au and brookite TiO₂

〇Kohei Tada¹, Yoyo Hnuma¹, Satoshi Ichikawa^1,2, Shingo Tanaka¹ (1.AIST, 2.Osaka Univ.)

Keywords:Au catalyst, Functional nano interface, brookite TiO2

Au/TiO₂ systems are typical nano-gold catalysts and have been widely studied as models for functional nano-interfaces. The crystal shape is important for functional nano-interfaces and influences the activity and durability of Au/TiO₂ catalysts. However, knowledge on the Au/brookite TiO₂ interaction is scarce. We prepared a Au/brookite TiO₂ catalyst which is active in low-temperature CO oxidation and performed transmission electron microscopy (TEM) observation on its interface structure. TEM revealed that gold nanoparticles were adsorbed on brookite TiO₂ (101). The Au/brookite TiO₂ (101) interaction was investigated using density functional theory (DFT) calculations. The calculated results revealed that brookite TiO₂ (101) can adsorb Au atoms more strongly than other TiO₂ surfaces. In the Au/brookite TiO₂, 2 eV stabilisation can be obtained by the surface complex formation. This result indicates that Au atom can be anchored even on stoichiometric and non-polar surfaces without any defect sites and doping.