KFM imaging revealed hydrophilic and hydrophobic regions on Nafion surfaces, correlating to ionic clusters and polymer backbones, respectively. It demonstrated that surface potential varies with hydration levels, influencing PEM functionality. CSAFM measurements, employing a Pt-coated AFM tip, quantified local ionic currents, mapping active proton-conductive channels. Results highlighted that increasing relative humidity enhances ionic cluster connectivity, improving overall conductivity.

This research underscores the importance of hydration control in PEM fuel cells and establishes KFM and CSAFM as effective tools for in situ analysis of PEM properties. These techniques support the advancement of efficient, durable fuel cell technologies.