2026-05-30 東京大学
分子―電極間相互作用によって自発的に終了する重合反応のメカニズム
＜関連情報＞
強力な超分子モノマー-電極相互作用による自己終結型アンダーポテンシャル電解重合の実現 Realization of Self-Terminating Underpotential Electropolymerization by Strong Supramolecular Monomer-Electrode Interaction
Yudai Yokoyama,Yuzu Kobayashi,Yasuyuki Yokota,Yasunobu Ando,and Yoshimitsu Itoh
Journal of the American Chemical Society Published: May 29, 2026
DOI:https://doi.org/10.1021/jacs.6c03733
Abstract
In this report, we show that electropolymerization of 3,4-ethylenedioxythiophene (EDOT) can take place at 0.4 V, a voltage far lower than the conventionally employed voltage of 1.0 V, in a self-terminating manner, when Au is employed as a working electrode. DFT calculations revealed that the highest occupied molecular orbital (HOMO) of EDOT is elevated by approximately 1 eV when it supramolecularly interacts with the Au surface compared to that without such direct interaction. In other words, monomers become highly reactive for oxidative polymerization when they are directly adsorbed onto Au. Once the polymer forms and covers the electrode surface, the monomer can no longer interact with the electrode surface, thus the polymerization is terminated. Such self-terminating polymerization behavior was supported by in situ electrochemical surface-enhanced Raman spectroscopy (EC-SERS) and the current profile during the voltage scan. This is in sharp contrast to electropolymerization under ordinary high-voltage conditions, where the polymer film continuously grows. This study may provide solutions to control the polymerization on the solid surface, which is considered to be very important for adhesives, coatings, and solid electrolyte interphase (SEI) formation. It is also expected to lead to new synthetic methods via electropolymerization for monolayer polymers, which have recently attracted attention for their potential to exhibit various functions.
