Boron-Doping Engineering in AgCd Bimetallic Catalyst Enabling Efficient CO2 Electroreduction to CO and Aqueous Zn-CO2 Batteries

The limited adsorption and activation of CO2 on catalyst and the high energy barrier for intermediate formation hinder the development of electrochemical CO2 reduction reactions (CO2RR). Herein, this work reports a boron (B) doping engineering in AgCd bimetals to alleviate the above limitations for efficient CO2 electroreduction to CO and aqueous Zn-CO2 batteries. Specifically, the B-doped AgCd bimetallic catalyst (AgCd-B) is prepared via a simple reduction reaction at room temperature. A combination of in situ experiments and density functional theory (DFT) calculations demonstrates that B-doping simultaneously enhances the adsorption and activation of CO2 and reduces the binding energy of the intermediates by moderating the electronic structure of bimetals. As a result, the AgCd-B catalyst exhibits a high CO Faraday efficiency (FECO) of 99% at -0.8 V versus reversible hydrogen electrode (RHE). Additionally, it maintains a FECO over 92% at a wide potential window of 600 mV (-0.6 to -1.1 V versus RHE). Furthermore, the AgCd-B catalyst coupled with the Zn anode to assemble aqueous Zn-CO2 batteries shows a power density of 20.18 mW cm(-2) and a recharge time of 33 h.