High carbonate ion conductance of a robust PiperION membrane allows industrial current density and conversion in a zero-gap carbon dioxide electrolyzer cell

A poly(aryl piperidinium)-based anion exchange membrane (PiperION) with high carbonate conductance is employed for CO 2 electrolysis to CO in conjunction with a tailored electrolyzer cell structure. This combination results in unprecedentedly high partial current densities in zero-gap cells ( j CO > 1.0 A cm −2 ), while maintaining high conversion (20-45%), selectivity (up to 90%) and low cell voltage (2.6-3.4 V). A new anion exchange membrane (PiperION) in conjunction with a tailored zero-gap electrolyzer cell allows unprecedented partial current densities.