2011年2月16日，我室杨金龙王兵赵爱迪等研究组合作在JOURNAL OF THE AMERICAN CHEMICAL SOCIETY上发表题为Molecular Oxygen Adsorption Behaviors on the Rutile TiO2(110)-1 x 1 Surface: An in Situ Study with Low-Temperature Scanning Tunneling Microscopy的论文。

Source: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY Volume: 133 Issue: 6 Pages: 2002-2009 Published: FEB 16 2011
Tan SJ (Tan, Shijing)1, Ji YF (Ji, Yongfei)1, Zhao Y (Zhao, Yan)1, Zhao AD (Zhao, Aidi)1, Wang B (Wang, Bing)1, Yang JL (Yang, Jinlong)1, Hou JG (Hou, J. G.)1
Addresses:
1. Univ Sci & Technol China, Hefei Natl Lab Phys Sci Microscale, Hefei 230026, Anhui Peoples R China
E-mail Addresses: bwang@ustc.edu.cn, jghou@ustc.edu.cn

Reprint Address: Wang, B (reprint author), Univ Sci & Technol China, Hefei Natl Lab Phys Sci Microscale, Hefei 230026, Anhui Peoples R China

Abstract: A knowledge of adsorption behaviors of oxygen on the model system of the reduced rutile TiO2(110)-1 x 1 surface is of great importance for an atomistic understanding of many chemical processes. We present a scanning tunneling microcopy (STM) study on the adsorption of molecular oxygen either at the bridge-bonded oxygen vacancies (BBOV) or at the hydroxyls (OH) on the TiO2(110)-1 x 1 surface. Using an in situ O-2 dosing method, we are able to directly verify the exact adsorption sites and the dynamic behaviors of molecular O-2. Our experiments provide direct evidence that an O-2 molecule can intrinsically adsorb at both the BBOV and the OH sites. It has been identified that, at a low coverage of O-2, the singly adsorbed molecular O-2 at BBOV can be dissociated through an intermediate state as driven by the STM tip. However, singly adsorbed molecular O-2 at OH can survive from such a tip-induced effect, which implies that the singly adsorbed O-2 at OH is more stable than that at BBOV. It is interesting to observe that when the BBO(V)s are fully filled with excess O-2 dosing, the adsorbed O-2 molecules at BBOV tend to be nondissociative even under a higher bias voltage of 2.2 V. Such a nondissociative behavior is most likely attributed to the presence of two or more O-2 molecules simultaneously adsorbed at a BBOV with a more stable configuration than singly adsorbed molecular O-2 at a BBOV.