Investigating the electrowetting of silver?based gas?diffusion electrodes during oxygen reduction reaction with electrochemical and optical methods

Porous gas-diffusion electrodes (GDEs) are widely used in electrochemical applications where a gaseous reactant is converted to target product. Important for silver-based GDEs the chlor-alkali and CO2 electrolysis processes which silver catalyzes oxygen- or carbon dioxide reduction reaction. The wetting of porous utmost importance achieved performance electrode: completely dry electrode will result low current densities due reduced active surface area while on other hand, flooded deteriorate access reactant. Therefore, we investigated oxygen reaction with different amounts hydrophobic agent polytetrafluoroethylene (PTFE) analyzed potential-induced behavior (electrowetting). electrolyte breakthrough was recorded by digital microscope subsequently evaluated via imaging analysis observed breached droplets. In order characterize state during transition steady-state, applied impedance spectroscopy measurements retrieved double-layer capacitance. Our results indicate that higher overvoltage facilitates electrolytes through electrode. Surprisingly, faster PTFE content. Porometry revealed GDE content has monomodal pore size distribution, whereas amount exhibit bimodal distribution. distribution time double layer capacitance leveling off correlates electrolyte. summary, emphasize complex interplay potential, composition, resulting structure requires further advanced considering parameters affecting as whole.