Abstract
Oxygen-containing species have been demonstrated to play a key role in facilitating electrocatalytic CO2 reduction(CO2RR),particularly in enhancing the selectivity towards multi-carbon(C2+)products.However,the underlying promotion mechanism is still under debate,which greatly limits the rational optimization of the catalytic performance of CO2RR.Herein,taking CO2 and O2 co-electrolysis over Cu as the prototype,we successfully clarified how O2 boosts CO2RR from a new perspective by employing comprehensive theoretical simulations.Our results demonstrated that O2 in feed gas can be rapidly reduced into *OH,leading to the partial oxidation of Cu surface under reduction conditions.Surface*OH accelerates the formation of quasi-specifically adsorbed K+due to the electrostatic interaction between *OH and K+ions,which significantly increases the concentration of K+near the Cu surface.These quasi-specifically adsorbed K+ions can not only lower the C-C coupling barriers but also promote the hydrogenation of CO2 to improve the CO yield rate,which are responsible for the remarkably enhanced efficiency of C2+products.During the whole process,O2 co-electrolysis plays an indispensable role in stabilizing surface *OH.This mechanism can be also adopted to understand the effect of high pH of electrolyte and residual O in oxide-derived Cu(OD-Cu)on the catalytic efficiency towards C2+products.Therefore,our work provides new insights into strategies for improving C2+products on the Cu-based cat-alysts,i.e.,maintaining partial oxidation of surface under reduction conditions.
基金项目
国家重点研发计划(2022YFA1503100)
国家重点研发计划(2021YFA1500700)
国家自然科学基金(22033002)
国家自然科学基金(92261112)
国家自然科学基金(22303011)
Basic Research Program of Jiangsu Province(BK20220800)
Basic Research Program of Jiangsu Province(BK20222007)
中央高校基本科研业务费专项(2242023R40016)
Big Data Computing Center of Southeast University()
National Supercomputing Center of Tianjin()
NETL
NSTL
万方数据