Abstract Recently, two-dimensional graphitic carbon nitrides have emerged as potential electrocatalysts for CO2 electroreduction (CO2ER). Herein, a series of transition metal (M=Mn-Cu, Ru-Ag) doped C3N monolayer (M-C3N) as a novel CO2ER catalyst has been investigated by employing the density functional method. By a careful computational screening, Mn-C3N is identified as the best catalyst for CO2ER, due to its high catalytic activity and high selectivity. HCOOH is the final product with a low overpotential of 0.04 V and a low kinetic energy barrier of 0.75 eV. The hydrogen evolution is also suppressed on Mn-C3N surface. Therefore, the CO2ER activity could be tuned by adjusting the metal atom in the C3N monolayer, which may shed new light on designing novel C3N-based CO2ER catalyst.

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5 过渡金属掺杂的 C3N 单层作为二氧化碳电还原的有效电催化剂：一项计算研究

摘要 最近，二维石墨碳氮化物已成为潜在的 CO2 电还原 (CO2ER) 电催化剂。在此，采用密度泛函方法研究了一系列过渡金属（M=Mn-Cu，Ru-Ag）掺杂的 C3N 单层（M-C3N）作为新型 CO2ER 催化剂。通过仔细的计算筛选，Mn-C3N 被确定为 CO2ER 的最佳催化剂，因为它具有高催化活性和高选择性。HCOOH 是最终产物，具有 0.04 V 的低过电位和 0.75 eV 的低动能势垒。Mn-C3N 表面的析氢也受到抑制。因此，可以通过调节 C3N 单层中的金属原子来调节 CO2ER 活性，这可能为设计新型 C3N 基 CO2ER 催化剂提供新思路。