Constructing a Hetero-interface Composed of Oxygen Vacancy- Enriched Co3O4 and Crystalline-Amorphous NiFe-LDH for Oxygen Evolution Reaction
Constructing a Hetero-interface Composed of Oxygen Vacancy- Enriched Co3O4 and Crystalline-Amorphous NiFe-LDH for Oxygen Evolution Reaction
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DOI：
10.1021/acscatal.1c03960
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发表时间：
2021-12-03
期刊：
影响因子：
12.9
通讯作者：
Wang, Ge
中科院分区：
文献类型：
--
作者：
Lv, Junjun;Wang, Linmeng;Wang, Ge
开发高性能的电催化剂是优化析氧反应（OER）缓慢动力学特性的有效策略。本文合成了一种以一维Co 3 O 4纳米线为核、二维NiFe-LDH纳米片为壳的泡沫镍负载型电催化剂（NiFe-60/Co3O4@NF）。将氟引入Co 3 O 4的前驱体Co（OH）F中，可提高其热稳定性并显著增加规则分布的氧空位，而电化学沉积的NiFe-LDH纳米片具有晶态/非晶态混合结构。结果表明，异质界面主要由NiFe-LDH中的Ni物种和Co（OH）F中的Co 3 O 4物种组成，有利于Co和Fe物种之间的相互作用，促进电子转移。同时，还确定了Co_3O_4中的氧空位与NiFe-LDH非晶区配位不饱和Fe物种之间的相互作用，最终完成了电子回溯。受益于这些因素，仅需要221和257 mV的低过电位来分别提供100和500 mA cm（-2）的电流密度，对于精心设计的NiFe-60/Co3O4@NF电催化剂，在OER期间具有34.6 mV dec（-1）的相当小的Tafel斜率。
The development of high-performance electro-catalysts is a highly efficient strategy to optimize the sluggish kinetic property of the oxygen evolution reaction (OER). Herein, we synthesize a kind of nickel foam (NF)-supported electrocatalyst composed of a one-dimensional Co3O4 nanowire as the core and a two-dimensional NiFe-LDH nanosheet as the shell (denoted as NiFe-60/Co3O4@NF). Fluorine is introduced into the precursor Co(OH)F of Co3O4, which results in improved thermal stability and significantly increased regularly distributed oxygen vacancies, while the electrochemically deposited NiFe-LDH nanosheets possess a crystalline/amorphous hybrid structure. As a result, the hetero-interface mainly constituting Ni species from NiFe-LDH and Co3O4 from Co(OH)F contributes to the interaction between Co and Fe species and facilitates the electron transfer. Simultaneously, the interaction between oxygen vacancies in Co3O4 and coordinatively unsaturated Fe species in the amorphous area in NiFe-LDH is also determined, finally completing the electron backtracking. Benefiting from these factors, only low overpotentials of 221 and 257 mV are required to deliver the current densities of 100 and 500 mA cm(-2), respectively, with a quite small Tafel slope of 34.6 mV dec(-1) during OER for the well-designed NiFe-60/Co3O4@NF electrocatalyst.