With the advantages of maximum metal utilization, single-atom catalysts (SACs) are emerging as promising catalysts in the CO₂ reduction reaction (CO₂RR) field. Herein, first-principles calculation is performed to investigate the CO₂-to-CO conversion mechanism by a serial of transition metal single transition metal atom supported on graphene systems (TM@Gr_s) as a CO₂ reduction catalyst. Among all SACs considered in this work, Cr@Gr_s exhibits a low limiting potential of −0.21 V, showing remarkable performance for CO₂RR. To understand activity origin of CO₂RR, we analyzed the effect of d-band centers of TM@Gr_s and investigated the charge transfer and bonding/antibonding states between the intermediates and TM atoms. These physical quantities provide a good explanation for the process of CO₂RR and show the theoretical guidance for proper catalyst discovery and better carbon circulation.

中文翻译：

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石墨烯负载的单原子催化剂电化学还原CO2的理论研究

凭借最大程度地利用金属的优势，单原子催化剂（SAC）成为了CO ₂还原反应（CO ₂ RR）领域中有希望的催化剂。在此，进行第一原理计算以研究通过负载在石墨烯体系上的一系列过渡金属单过渡金属原子（TM @ Gr _s）作为CO ₂还原催化剂的CO ₂到CO转化机理。在这项工作中考虑的所有SAC中，Cr @ Gr _s显示出-0.21 V的低极限电势，显示出出色的CO ₂ RR性能。为了了解CO ₂ RR的活动起源，我们分析了TM @ Gr _s的d波段中心的影响_。并研究了中间体与TM原子之间的电荷转移和键/反键状态。这些物理量为CO ₂ RR的过程提供了很好的解释，并为正确发现催化剂和改善碳循环提供了理论指导。