CO2 electrolysis to multicarbon products in strong acid

Potassium helps CO2 compete in acidElectrochemical reduction of carbon dioxide (CO2) is a promising means of converting this greenhouse gas into valuable fuels and chemicals. However, two competing reactions restrict the efficiency of this process. In base, much of the CO2 is trapped as carbonate before reduction; in acid, protons outpace CO2 at catching electrons from the cathode. Huang et al. report that a high dose of potassium ions can help to solve the latter problem. By concentrating potassium ions at the electrode, high selectivity toward CO2 reduction at high current in acid is possible, which the authors attribute to electrostatic stabilization of the desired adsorbates.Science, abg6582, this issue p. 1074Carbon dioxide electroreduction (CO2R) is being actively studied as a promising route to convert carbon emissions to valuable chemicals and fuels. However, the fraction of input CO2 that is productively reduced has typically been very low,