The Polymer Society of Korea

Abstract

We report a collaborative effort to design ion-conducting polymers (ionomers) as catalyst binders for CO₂ electrolysis to enhance activity, selectivity, and durability. While ionomers shape the microenvironment near the electrode surface, the relationship between their molecular structure and catalytic performance remains poorly understood. We address this knowledge gap by synthesizing a library of ionomers where specific structural moieties (e.g., side chains, ion-conducting groups, and charge density) are varied systematically. These features influence hydrophobicity, intermediate stability, reactant activity, and local pH. Using operando vibrational spectroscopy and computational modeling, we tracked key intermediates and uncovered fundamental mechanisms. These studies establish fundamental structure-property-performance relationships and demonstrate how molecular ionomer design enables precise interface control to optimize electrocatalysis.