Surfactant-modified Zn nanosheets on carbon paper for electrochemical CO2 reduction to CO

We report a strategy that tunes the CO2 and proton concentrations near the electrode-electrolyte interface using surfactant modification with various amounts (0.05, 0.8, 1.6, and 3.2 mg) of hexadecyl trimethyl ammonium bromide (CTAB). The positively charged group of CTAB favors CO2 surface diffusion and inhibits excessive proton accumulation on Zn nanosheets on carbon paper. A CO faradaic efficiency of 95.6% and a total ampere density of -13.1 mA cm-2 were obtained over the optimal CTAB-modified Zn electrode at -1.1 V with stability over 12 hours.