Presentation Information
[3H16]Edge-selective photo-stimulated desorption via localized anionic states of nitric oxide from a gold surface
*Hiroyuki Koshida1,4, Nobuto Tanaka1, Shunsuke Tanaka2,5, Wataru Osada2,5, Jun Yoshinobu2, Tomokazu Yasuike3, Hiroshi Okuyama1 (1. Department of Chemistry, Graduate School of Science, Kyoto University, 2. The Institute for Solid State Physics, The University of Tokyo, 3. Division of Arts and Sciences, Graduate School of Arts and Sciences, The Open University of Japan, 4. Department of Basic Science, The University of Tokyo, 5. National Institute for Advanced Industrial Science and Technology)
Understanding how local environments govern photoinduced surface reactions is key to advancing photocatalysis. We investigate photo-stimulated desorption (PSD) of nitric oxide (NO) from the Au(110)-(1×2) surface using infrared spectroscopy and scanning tunneling microscopy under low-intensity continuous-wave laser irradiation. Unlike thermal desorption, which follows adsorption energy hierarchy (on-top → bridge), PSD occurs preferentially at the edges of NO clusters, independent of adsorption site. Density functional theory calculations show that photoexcited electrons localize at cluster edges, where electrostatic repulsion is reduced and transient anionic states (NO−) are stabilized. This edge localization promotes desorption via the Antoniewicz model. Our findings highlight the critical role of electronic heterogeneity in non-thermal surface reactions and suggest that local structure governs photocatalytic reactivity.