Our official English website, www.x-mol.net, welcomes your
feedback! (Note: you will need to create a separate account there.)
Theoretical Density Functional Theory Study of Electrocatalytic Activity of MN4-Doped (M = Cu, Ag, and Zn) Single-Walled Carbon Nanotubes in Oxygen Reduction Reactions
ACS Omega ( IF 3.7 ) Pub Date : 2020-12-27 , DOI: 10.1021/acsomega.0c04727
Anton V. Kuzmin 1, 2 , Bagrat A. Shainyan 1
ACS Omega ( IF 3.7 ) Pub Date : 2020-12-27 , DOI: 10.1021/acsomega.0c04727
Anton V. Kuzmin 1, 2 , Bagrat A. Shainyan 1
Affiliation
|
The mechanism of oxygen reduction reaction (ORR) on transition metal-doped nitrogen codoped single-walled nanotubes, C114H24MN4 (MN4-CNT where M = Zn, Cu, or Ag; N = pyridinic nitrogen), has been studied with the density functional theory method at the ωB97XD/DGDZVP level of theory. The charge density analysis revealed two active sites of the catalyst toward ORR: the MN4 site and the C═C bond of the N–C═C–N metal-chelating fragment (C2 site). The structure of O-containing adsorbates (O2*, HOO*, O*, HO*, etc.) on the two sites and the corresponding adsorption energies were determined. The analysis of the free energy diagrams allows to conclude that the 4e– mechanism of ORR is thermodynamically preferable for all the studied catalysts. The probability of the 2e– mechanism of ORR with the formation of hydrogen peroxide decreases in the order Cu > Ag > Zn. The most and the least exergonic steps of the conventional 4e– mechanism of ORR on each active site of model catalysts as well as the electrode potentials of deceleration and of maximum catalytic activity in both acidic and alkaline media are determined. The relative catalytic activity toward ORR increases in the order Zn < Ag ≪ Cu and is mainly attributed to the C2 site rather than the MN4 site, while combined catalytic activity of the two sites (AgN4/C2 sites) is predicted for the AgN4-CNT catalyst.
中文翻译：
MN 4掺杂（M = Cu，Ag和Zn）单壁碳纳米管在氧还原反应中的电催化活性的理论密度泛函理论研究
过渡金属掺杂的氮共掺杂单壁纳米管C 114 H 24 MN 4（MN 4 -CNT，其中M = Zn，Cu或Ag； N =吡啶氮）上的氧还原反应（ORR）机理在ωB97XD/ DGDZVP理论水平上使用密度泛函理论方法进行了研究。电荷密度分析揭示了催化剂朝向ORR的两个活性位：MN 4位和N–C═C–N金属螯合片段的C═C键（C 2位）。含O的吸附物（O 2 *，HOO *，O *，HO *等），并确定相应的吸附能。自由能图的分析允许得出结论，4 ë - ORR的机构是用于所有研究的催化剂热力学优选的。的2的概率ë - ORR的机构与过氧化氢的形成的顺序的Cu> AG>锌减小。常规4 e的最大和最少运动步骤–确定了ORR在模型催化剂的每个活性位点上的机理，以及在酸性和碱性介质中的减速和最大催化活性的电极电位。对ORR的相对催化活性按Zn <Ag≪ Cu的顺序增加，并且主要归因于C 2位点而不是MN 4位点，而预测这两个位点（AgN 4 / C 2位点）的组合催化活性为AgN 4 -CNT催化剂。
更新日期：2021-01-12
中文翻译：
MN 4掺杂（M = Cu，Ag和Zn）单壁碳纳米管在氧还原反应中的电催化活性的理论密度泛函理论研究
过渡金属掺杂的氮共掺杂单壁纳米管C 114 H 24 MN 4（MN 4 -CNT，其中M = Zn，Cu或Ag； N =吡啶氮）上的氧还原反应（ORR）机理在ωB97XD/ DGDZVP理论水平上使用密度泛函理论方法进行了研究。电荷密度分析揭示了催化剂朝向ORR的两个活性位：MN 4位和N–C═C–N金属螯合片段的C═C键（C 2位）。含O的吸附物（O 2 *，HOO *，O *，HO *等），并确定相应的吸附能。自由能图的分析允许得出结论，4 ë - ORR的机构是用于所有研究的催化剂热力学优选的。的2的概率ë - ORR的机构与过氧化氢的形成的顺序的Cu> AG>锌减小。常规4 e的最大和最少运动步骤–确定了ORR在模型催化剂的每个活性位点上的机理，以及在酸性和碱性介质中的减速和最大催化活性的电极电位。对ORR的相对催化活性按Zn <Ag≪ Cu的顺序增加，并且主要归因于C 2位点而不是MN 4位点，而预测这两个位点（AgN 4 / C 2位点）的组合催化活性为AgN 4 -CNT催化剂。
京公网安备 11010802027423号