第一性原理计算筛选轴向配体用于锚定锰单原子电催化还原二氧化碳  

First-principles Computational Screening of Axial Ligands for Anchored Manganese Single-atom Electrocatalytic Reduction of Carbon Dioxide

作　　者：牛维炳 程平 张淑平[1] NIU Wei-bing;CHENG Ping;ZHANG Shu-ping(School of Materials and Chemistry,University of Shanghai for Science and Technology,Shanghai 200093,China)

机构地区：[1]上海理工大学材料与化学学院,上海200093

出　　处：《广州化学》2022年第5期54-61,共8页Guangzhou Chemistry

摘　　要：设计了5种Mn@dv-Nx催化剂、选择了7种配体(X=-F、-OH、-CO、-NH_(3)、-N(Me)_(3)、-PH_(3)和P(Me)_(3)),运用理论计算研究了不同轴向配体对Mn@dv-Nx电催化CO_(2)还原的影响。经过选择性筛选,其中6种催化剂(Mn@dv-N4-F、Mn@dv-N4-PH_(3)、Mn@dv-N2-1-P(Me)_(3)、Mn@dv-N3-P(Me)_(3)、Mn@dv-N2-2-CO和Mn@dv-N4-CO)都具有良好的催化活性和并且对产物HCOOH具有的很高的选择性。只有Mn@dv-N2-1-P(Me)_(3)对产物HCHO、CH_(3)OH和CH_(4)有较好的催化活性,这三种产物的速率限制步骤是CO_(2)加氢生成*OCHO。在催化剂Mn@dv-N2-1-P(Me)_(3)上,生成*OCHO只需要克服0.716 eV。通过差分电荷电子分析方法证明*OCHO与Mn@dv-N2-1-P(Me)_(3)相互作用强。配体P(Me)_(3)的加入增强了催化剂与中间产物的相互作用,有效提高了催化剂的催化活性。Five Mn@dv-Nx catalysts and seven selected ligands(X=-F,-OH,-CO,-NH_(3),-N(Me)_(3),-PH_(3) and P(Me)_(3))were designed and the effects of different axial ligands on the electrocatalytic CO_(2) reduction by Mn@dv-Nx were investigated using theoretical calculations.After selective screening,six catalysts(Mn@dv-N4-F,Mn@dv-N4-PH_(3),Mn@dv-N2-1P(Me)_(3),Mn@dv-N3-P(Me)_(3),Mn@dv-N2-2-CO and Mn@dv-N4-CO)showed good catalytic activity and high selectivity for the product HCOOH.Only Mn@dv-N2-1-P(Me)_(3) has good catalytic activity for the products HCHO,CH_(3)OH and CH_(4),and the rate limiting step for these three products is the hydrogenation of CO_(2) to form*OCHO.On the catalyst Mn@dv-N2-1-P(Me)_(3),the formation of*OCHO requires only 0.716 eV to be overcome.It has been demonstrated by differential charge electron analysis that*OCHO interacts strongly with Mn@dv-N2-1-P(Me)_(3).The addition of the ligand P(Me)_(3) enhances the interaction between the catalyst and the intermediates,effectively improving the catalytic activity of the catalyst.

关 键 词：理论计算 Mn-N-C催化剂 CO_(2)还原 轴向配体 电催化 

分 类 号：O643[理学—物理化学]