Boosting CO2 electroreduction on a Zn electrode via concurrent surface reconstruction and interfacial surfactant modification.

Abstract

Herein, we report an effective strategy for improving the electrocatalytic CO2 reduction reaction (CO2RR) performance of a Zn foil electrode via concurrent surface reconstruction and interfacial surfactant modification. The oxide-derived and CTAB-modified Zn electrode (OD-Zn-CTAB) prepared by electrochemically reducing the air-annealed Zn foil electrode in the presence of CTAB exhibits high electrocatalytic activity and selectivity for CO production with a CO partial current density (jCO) of 8.2 mA cm-2 and a CO faradaic efficiency (FECO) of 90% at -1.0 V vs. the reversible hydrogen electrode (RHE), greatly outperforming the pristine Zn foil (FECO = 32.0%; jCO = 0.5 mA cm-2) and OD-Zn (FECO = 77.6%; jCO = 5.0 mA cm-2) obtained by electroreduction of annealed Zn. The greatly enhanced CO2RR performance of OD-Zn-CTAB can be attributed to the increased number of active sites originating from the surface reconstruction and the formation of a favorable CTAB-modified electrode/electrolyte (E/E) interface that can efficiently adsorb and activate CO2 while inhibiting the competitive H2 evolution reaction.