In liquid water, a large number of water molecules are mutually linked by hydrogen bonds. Their collective motion emerges as oscillation and relaxation in the terahertz range. This research elucidated the potential response of collective motions of water at an electrochemical interface by the newly developed terahertz spectroscopy and MD simulation. Notably, it was found that local defects are created in the interfacial hydrogen bond network at potentials where hydrogen evolution reactions occur and that the motion of water molecules increases along the electrode surface. The research results will help realize a carbon-free society, including highly efficient hydrogen generation.

Scientific journal: Chemical Science

Ikeda Lab ／Ogata Lab.