The 70th JSAP Spring Meeting 2023

Presentation information

Poster presentation

6 Thin Films and Surfaces » 6.6 Probe Microscopy

[16p-PA10-1~11] 6.6 Probe Microscopy

Thu. Mar 16, 2023 4:00 PM - 6:00 PM PA10 (Poster)

4:00 PM - 6:00 PM

[16p-PA10-11] Exploration of charge properties of Au NPs on rutile TiO2(110) surface by AFM/KPFM at 78 K

〇(DC)Qiang Zhu1, Yasuhiro Sugawara1, Yanjun Li1 (1.Osaka Univ.)

Keywords:TiO2(110), AFM, Au NPs

In the heterogeneous catalysis, the noble metal participated catalytic reactions are widely employed due to its high catalytic activity. In calculation results, it is confirmed that the Au NPs bind to surface and draw electrons from surface defects, becoming negatively charged Au NPs [1]. The charged Au NPs weaken the O-O bond of O2 making oxidation reactions more facile [2, 3]. In our previous research, charge transformation between Au and substrate is still unknown [4]. And charge states of single Au atom among Au-, Au0 and Au+ have been clarified, and single charge operation of Au atom can be achieved by Kelvin probe force spectroscopy (KPFS) method [5].
In this work, we investigated the different charge state of Au NPs on the oxidized TiO2(110) surface by AFM and KPFM at 78 K. The dimer and trimer Au NPs were investigated, different adsorption sites (oxygen vacancy, oxygen adatom, bridge oxygen) and configuration of Au NPs are strongly influence its charge state. This work is important for understanding the catalytic mechanism of the Au/TiO2 catalytic reactions and controlling the reaction pathway.