Self-pressurizing nanoscale capsule catalysts for CO2 electroreduction to acetate or propanol

The selective one-step CO 2 electroreduction reaction (CO 2 RR) to acetate and propanol has garnered intense interest. Here we report the design of self-pressurizing nanoscale capsule catalysts for the CO 2 RR. A high-pressure CO intermediate environment is created around copper catalysts by a permselective enclosure. Microkinetic modelling, 13 CO 2 / 12 CO co-feed experiments and in situ Raman spectroscopy confirm that a unique CO–CO 2 coupling path is involved, which is only initiated at high CO intermediate pressure. This pathway benefits acetate production due to the kinetic and energetic advantages of COCO 2 *. The acetate Faradaic efficiency is 38.5 ± 2.2% (8 times higher than that achieved without enclosure) and the acetate partial current density is 328 ± 19 mA cm −2 , which surpasses the performance of previous CO 2 RR catalysts. In situ investigation indicates that the CO pressure inside the nanoscale capsule catalysts can reach 8 ± 3 bar. Furthermore, self-pressurizing nanoscale capsule catalysts with a CuI-derived core can reduce CO 2 to propanol with a Faradaic efficiency of 25.7 ± 1.2% and a conversion rate of 155 ± 3 mA cm −2 .