Emerging as a new class of two-dimensional materials with atomically thin layers,MBenes have great potential for many important applications such as energy storage and electrocatalysis.Toward mitigating carbon footpri...Emerging as a new class of two-dimensional materials with atomically thin layers,MBenes have great potential for many important applications such as energy storage and electrocatalysis.Toward mitigating carbon footprint,there has been increasing interest in CO_(2)/CO conversion on MBenes,but mostly focused on C_(1)products.C^(2+)chemicals generally possess higher energy densities and wider applications than C_(1)counterparts.However,C–C coupling is technically challenging because of high energy requirement and currently few catalysts are suited for this process.Here,we explore electrochemical CO reduction reaction to C_(2)chemicals on Mo_(2)B_(2)O_(2)MBene via density-functional theory calculations.Remarkably,the most favorable CO–COH coupling is revealed to be a spontaneous and barrierless process,making Mo_(2)B_(2)O_(2)an efficient catalyst for C–C coupling.Among C_(1)and C_(2)chemicals,ethanol is predicted to be the primary product.Furthermore,by charge and bond analysis,it is unraveled that there exist significantly more unbonded electrons in the C atom of intermediate*COH than other C_(1)intermediates,which is responsible for the facile C–C coupling.From an atomic scale,this work provides microscopic insight into C–C coupling process and suggests Mo_(2)B_(2)O_(2)a promising catalyst for electrochemical CO reduction to C_(2)chemicals.展开更多
基金the A*STAR LCER-FI project(LCERFI01-0033 U2102d2006)the Ministry of Education of Singapore and the National University of Singapore(C-261-000-207-532/C-261-000-777-532 and R-279-000-574-114)for financial support.
文摘Emerging as a new class of two-dimensional materials with atomically thin layers,MBenes have great potential for many important applications such as energy storage and electrocatalysis.Toward mitigating carbon footprint,there has been increasing interest in CO_(2)/CO conversion on MBenes,but mostly focused on C_(1)products.C^(2+)chemicals generally possess higher energy densities and wider applications than C_(1)counterparts.However,C–C coupling is technically challenging because of high energy requirement and currently few catalysts are suited for this process.Here,we explore electrochemical CO reduction reaction to C_(2)chemicals on Mo_(2)B_(2)O_(2)MBene via density-functional theory calculations.Remarkably,the most favorable CO–COH coupling is revealed to be a spontaneous and barrierless process,making Mo_(2)B_(2)O_(2)an efficient catalyst for C–C coupling.Among C_(1)and C_(2)chemicals,ethanol is predicted to be the primary product.Furthermore,by charge and bond analysis,it is unraveled that there exist significantly more unbonded electrons in the C atom of intermediate*COH than other C_(1)intermediates,which is responsible for the facile C–C coupling.From an atomic scale,this work provides microscopic insight into C–C coupling process and suggests Mo_(2)B_(2)O_(2)a promising catalyst for electrochemical CO reduction to C_(2)chemicals.