Ag layer deposited on Zn by physical vapor deposition with enhanced CO selectivity for electrochemical CO_2 reduction

摘要

The electrocatalytic reduction of carbon dioxide (CO2) is a promising way to reduce CO2 and to produce valuable products. However, CO2 reduction still have challenges, such as, low catalytic activity, selectivity, and stability of catalysts. In the present study, we prepared Ag nanolayers (2, 5, and 10 nm) sputtered on polycrystalline Zn (AgZn) catalysts by a physical vapor deposition for the electrochemical CO2 reduction to carbon monoxide (CO). Among them, a 2 nm Ag layer deposited catalyst on Zn showed the faradaic efficiency of 84.2% with a CO partial current density of 2.97 mA cm(-2) at -1.0 V vs. RHE. Such enhanced electrochemical reduction activity, selectivity, and stability were attributed to the synergetic effect between Ag and Zn, which was confirmed by X-ray photoelectron spectroscopy (XPS) data. The results indicate that the proposed catalyst can provide one of efficient ways for the CO2 reduction reaction.