[14a-PB5-1~14] 6.6 Probe Microscopy

[14a-PB5-1] Tip-Induced Control of Oxygen Molecular Rotation on the Rutile TiO₂ (110) Surface using Atomic Force Microscopy

〇Yuuki Adachi¹, Yasuhiro Sugawara¹, Yanjun Li¹ (1.Osaka Univ.)

Keywords:Kelvin probe force microscopy, Titanium dioxide, Oxygen molecule

The discovery of adsorption state within the single-molecular level is particularly important for the catalytic field of titanium dioxide (TiO₂). In this study, the adsorption state of oxygen molecules was investigated using an atomic force microscopy (AFM) operating in an ultra-high vacuum at 78K. In the case of STM, it is well known that the inelastic tunneling can induce the single molecule rotation. However, this method is not suitable for oxygen molecules which can be easily dissociated by accepting electrons. Here we exploit force modulated AFM to overcome such limitation and control the rotation using an electric field which is applied between tip and sample. From these results, we successfully controlled the rotation between the bistable adsorption states. We anticipate that our approach can give a fundamental insight for the catalytic activity of metal nanoparticles on the metal oxide surface.