Imaging the surface potential at the steps on the rutile TiO2(110) surface by Kelvin probe force microscopy

Beilstein Journal of Nanotechnology

Huan Fei Wen¹  Yuuki Adachi¹  Masato Miyazaki¹  Quanzhen Zhang¹  Yan Jun Li¹  Yasuhiro Sugawara¹  Jan Brndiar²  Ivan Štich² 

[1] Department of Applied Physics, Graduate School of Engineering, Osaka University, 2-1 Yamdaoka, Suita, Osaka 565-0871, Japan;Institute of Physics, CCMS, Slovak Academy of Sciences, Bratislava, Slovakia;

关键词: catalyst;    Kelvin probe force microscopy;    Smoluchowski effect;    step;    titanium dioxide;   

DOI  :  10.3762/bjnano.10.122

来源: DOAJ

【 摘 要 】

Although step structures have generally been considered to be active sites, their role on a TiO2 surface in catalytic reactions is poorly understood. In this study, we measured the contact potential difference around the steps on a rutile TiO2(110)-(1 × 1) surface with O2 exposure using Kelvin probe force microscopy. A drop in contact potential difference was observed at the steps, indicating that the work function locally decreased. Moreover, for the first time, we found that the drop in contact potential difference at a <1−11> step was larger than that at a <001> step. We propose a model for interpreting the surface potential at the steps by combining the upward dipole moment, in analogy to the Smoluchowski effect, and the local dipole moment of surface atoms. This local change in surface potential provides insight into the important role of the steps in the catalytic reaction.

【 授权许可】

Unknown