Presentation Information
[3H15]Control of tunneling conductance by electric-field-driven proton transfer in a self-assembled heterobilayer film on Au substrates
Riku Muneyasu1, Tomoko Fujino2,3, Akira Ueda2,4, Yusuke Kanematsu5, Masanori Tachikawa6, Jun Yoshinobu2, Hatsumi Mori2, *Hiroyuki S. Kato1 (1. Gradiate School of Science, Osaka University, 2. ISSP, Univ. of Tokyo, 3. Graduate School of Engineering Science, Yokohama National Univ., 4. Faculty of Advanced Science and Technology, Kumamoto Univ., 5. Graduate School of Advanced Science and Engineering, Hiroshima Univ., 6. Graduate School of Nanobioscience, Yokohama City Univ.)
We report the first observation of reversible tunneling conductivity switching induced by external electric field (EEF) for a proton (H+) donor/acceptor bilayer film on Au substrates under ambient conditions. The heterobilayer film was selfassembled through two-step immersion: the H+-donor, the H+-electron-correlated Cat-TTF molecule, was hydrogen-bonded to the H+-accepting imidazole-terminated alkanethiolate selfassembled monolayer on Au(111). The bilayer film topographies, adsorption states, and physical properties were characterized by using several spectroscopic and microscopic methods. In particular, STM measurements revealed reversible changes in the tunneling conductivity of the bilayer film depending on EEF stimulation. This is attributed to reversible EEF-induced H+-transfer in the bilayer, based on theoretical model calculations. Notably, the reversible response exhibited hysteresis, indicating that the bilayer film could function as a molecular memory driven by H+ transfer.