Toward Understanding the Role of Electric Double Layer Structure and Hydration in Electrocatalysis: Insights from AFM

Understanding why hydrogen/oxygen electrocatalysis slows dramatically in alkaline media remains a key challenge for sustainable energy technologies. Proposed mechanisms involve electric double layer (EDL) structure, water orientation, and ion-specific adsorption, yet direct nanoscale evidence has been lacking. We employ a dual-scale electrochemical AFM approach combining force spectroscopy and atomic-resolution imaging to probe catalyst–electrolyte interfaces in situ under varying pH, ions, and potentials. Preliminary results on Pt and Au reveal potential-dependent hydration forces and nanoscale surface restructuring, correlating with changes in local charge density and EDL organization. These insights provide a microscopic link between electrolyte composition, interfacial structure, and electrocatalytic activity, offering new strategies to overcome kinetic limitations in alkaline environments.