Boosting alkaline hydrogen evolution: the dominating role of interior modification in surface electrocatalysis
Boosting alkaline hydrogen evolution: the dominating role of interior modification in surface electrocatalysis
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DOI：
10.1039/d0ee01750g
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发表时间：
2020-09-01
影响因子：
32.5
通讯作者：
Yang, Yang
中科院分区：
文献类型：
--
作者：
Li, Zhao;Niu, Wenhan;Yang, Yang
碱性析氢反应（A-HER）在清洁氢燃料生产方面具有巨大的前景，但其实际应用受到碱性溶液中水解离动力学缓慢的严重阻碍。传统的提高A-HER催化剂电化学动力学性能的方法主要集中在催化剂表面改性上，但由于催化剂表面失活，仍不能满足实际水电解的要求。在这里，我们报告了一个内部修改策略，以显着提高A-HER性能。具体而言，痕量的Pt被掺杂在内部Co2 P（Pt-Co2 P）中以引入比表面改性的催化剂更强的掺杂剂-主体相互作用。因此，局部的化学状态和电子结构的催化剂被调整，以提高电子迁移率，降低氢吸附和H-H键形成的能量障碍。作为概念验证，经过修饰的Pt-Co2 P在接近零伏时显示出降低的A-HER起始电位，2 mV和58 mV的低过电位，以实现10和100 mA cm（-2），以及长期使用的出色耐久性。经过修饰的Pt-Co2 P具有比Pt/C和其他最先进的电催化剂更优越的上级A-HER性能。这项工作将为A-HER催化剂的设计开辟一条新的途径。
The alkaline hydrogen evolution reaction (A-HER) holds great promise for clean hydrogen fuel generation but its practical utilization is severely hindered by the sluggish kinetics for water dissociation in alkaline solutions. Traditional ways to improve the electrochemical kinetics for A-HER catalysts have been focusing on surface modification, which still can not meet the demanding requirements for practical water electrolysis because of catalyst surface deactivation. Herein, we report an interior modification strategy to significantly boost the A-HER performance. Specifically, a trace amount of Pt was doped in the interior Co2P (Pt-Co2P) to introduce a stronger dopant-host interaction than that of the surface-modified catalyst. Consequently, the local chemical state and electronic structure of the catalysts were adjusted to improve the electron mobility and reduce the energy barriers for hydrogen adsorption and H-H bond formation. As a proof-of-concept, the interior-modified Pt-Co2P shows a reduced onset potential at near-zero volts for the A-HER, low overpotentials of 2 mV and 58 mV to achieve 10 and 100 mA cm(-2), and excellent durability for long-term utilization. The interior-modified Pt-Co2P delivers superior A-HER performance to Pt/C and other state-of-the-art electrocatalysts. This work will open a new avenue for A-HER catalyst design.