Doping sp-hybridized B atoms in graphyne supported single cobalt atoms for hydrogen evolution electrocatalysis
Doping sp-hybridized B atoms in graphyne supported single cobalt atoms for hydrogen evolution electrocatalysis
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DOI：
10.1016/j.ijhydene.2019.08.195
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发表时间：
2019-10-18
影响因子：
7.2
通讯作者：
Shen, Zhemin
中科院分区：
文献类型：
--
作者：
Gao, Xiaoping;Zhou, Yanan;Shen, Zhemin
电化学水分解制氢被认为是一种很有前途的清洁氢气生产方法。然而，开发高效廉价的电催化剂是析氢反应(HER)的重要组成部分。在这里，我们提出了一种多方面的原子(SP(2)和SP杂化的硼)掺杂策略，通过密度泛函理论计算直接精细地改变活性中心的电子结构和HER的性能。结果表明，B原子的掺杂可以提高Co原子与B掺杂纳米片之间的结合强度。同时，Co@B-1-GY和Co@B-2-GY催化剂具有良好的热力学稳定性和较高的催化活性。有趣的是，Co@B-2-GY催化剂具有理想的她的性能，其Delta G(H中心点)值为-0.004 eV。此外，掺杂了Sp(2)或Sp杂化的B原子使Co原子的d带中心上移。Sp杂化的B原子的浓度对Co原子的电子转化有正的影响。随着杂化B原子浓度的增加，H原子和Co原子之间的相互作用变强，相应的催化剂表现出迟缓的动力学行为。这一研究可以为实验小组通过精确掺杂多面原子来直接、连续地控制对HER的催化活性提供有用的指导。(C)2019氢能出版有限责任公司。爱思唯尔有限公司出版。保留所有权利。
Electrochemical water splitting to hydrogen is considered as a promising approach for clean H-2 production. However, developing highly active and inexpensive electrocatalysts is an important part of the hydrogen evolution reaction (HER). Herein, we present a multifaceted atom (sp(2)-and sp-hybridized boron) doping strategy to directly fine-modify the electronic structures of the active site and the HER performance by the density functional theory calculations. It is found that the binding strength between the Co atom and the B doped graphyne nanosheets can be enhanced by doping B atoms. Meanwhile, the Co@B-1-GY and Co@B-2-GY catalysts exhibit good thermodynamic stability and high HER catalytic activity. Interestingly, the Co@B-2-GY catalyst has an ideal HER performance with the Delta G(H center dot) value of -0.004 eV. Moreover, the d-band center of the Co atoms is upshifted by the sp(2)-or sp-hybridized B dopants. The concentrations of the sp-hybridized B atoms have a positive effect on the electrons transformation of the Co atoms. The interaction between the H and Co atoms becomes strong with the increase of the concentrations of the sp-hybridized B atoms and thus the corresponding catalysts show sluggish HER kinetics. This investigation could provide useful guidance for the experimental groups to directly and continuously control the catalytic activity towards HER by precisely doping multifaceted atoms. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.