Controlling Wettability of Electrodes for Enhanced Multi-Phase Electrochemical Reactions

Abstract

Multi-phase electrochemical reactions are academically and practically interesting subjects. Examples include hydrogen evolution and CO2 reduction reactions, which can be utilized for the efficient storage and utilization of excess renewable electricity. In these reactions, the interface between solid, liquid, and gas phases play a critical role in the efficiency and stability of electrodes/catalysts. However, most conventional studies have been focused on the development of efficient electrocatalysts, whereas less attention has been paid to the engineering of electrode wettability. In this talk, I will present our recent achievements in the development of extremely bubble-repellent (superaerophobic) electrodes using porous hydrogels for enhanced hydrogen evolution reactions. The porous and hydrophilic nature of hydrogels can impart extremely bubble-repellent properties to the underlying electrodes, regardless of their types and morphologies, and minimize the blocking of catalytically active electrode surfaces. As a result, hydrogel-coated electrodes exhibit significantly enhanced performance for hydrogen evolution reactions by facilitating the removal of gas bubbles from the electrode surface. Lastly, I will also briefly review recent promising results on the engineering of electrode wettability for CO2 reduction reactions.