催化学报 ›› 2022, Vol. 43 ›› Issue (9): 2354-2362.DOI: 10.1016/S1872-2067(21)63916-5

• 可再生燃料的光催化和光电催化合成专栏 • 上一篇    下一篇

多碳界面工程用于促进NiFe纳米复合电催化剂的产氧反应

乔玉彦a,b,, 潘艳秋a,, 张江威b, 王彬b, 武婷婷b, 范文俊b, 曹雨程b, Rashid Mehmoodb, 张飞b, 章福祥b,*()   

  1. a大连理工大学化工学院, 辽宁大连116024
    b中国科学院大连化学物理研究所, 催化基础国家重点实验室, 洁净能源国家实验室, 能源材料化学协同创新中心, 辽宁大连116023
  • 收稿日期:2021-07-01 接受日期:2021-08-05 出版日期:2022-09-18 发布日期:2022-07-20
  • 通讯作者: 章福祥
  • 作者简介:第一联系人:

    †共同第一作者.

  • 基金资助:
    国家重点研究开发计划(2020YFA0406102);国家自然科学基金(21925206);国家自然科学基金(21633009);中国科学院国际合作伙伴计划(121421KYSB20190025);中国科学院大连清洁能源国家实验室(DNL)合作基金(DNL 201913);DICP创新研究基金(DICP I201927);辽宁省振兴人才计划(XLYC1807241)

Multiple carbon interface engineering to boost oxygen evolution of NiFe nanocomposite electrocatalyst

Yuyan Qiaoa,b,, Yanqiu Pana,, Jiangwei Zhangb, Bin Wangb, Tingting Wub, Wenjun Fanb, Yucheng Caob, Rashid Mehmoodb, Fei Zhangb, Fuxiang Zhangb,*()   

  1. aSchool of Chemical Engineering, Dalian University of Technology, Dalian 116024, Liaoning, China
    bState Key Laboratory of Catalysis, iChEM, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian National Laboratory for Clean Energy, Dalian 116023, Liaoning, China
  • Received:2021-07-01 Accepted:2021-08-05 Online:2022-09-18 Published:2022-07-20
  • Contact: Fuxiang Zhang
  • About author:First author contact:

    †Contributed equally to this work.

  • Supported by:
    National Key Research and Development Program of China(2020YFA0406102);National Natural Science Foundation of China(21925206);National Natural Science Foundation of China(21633009);International Partnership Program of Chinese Academy of Sciences(121421KYSB20190025);Dalian National Laboratory for Clean Energy (DNL) Cooperation Fund, Chinese Academy of Sciences(DNL 201913);DICP foundation of innovative research(DICP I201927);Liaoning Revitalization Talents Program(XLYC1807241)

摘要:

NiFe基电催化剂在水氧化反应中已经得到了广泛研究, 但是, 基于多界面修饰对电催化析氧反应(OER)的研究仍然不足. 本课题组开发了通过多种碳基界面工程的协同作用来提高NiFe基纳米电催化剂OER性能的方法. 在碳纤维纸(CFP)上原位生长碳纳米管以改善CFP和NiFeOxHy之间的界面, 同时采用碳复合NiFeOxHy的策略优化NiFeOxHy界面的电荷转移和电子结构. 基于这种策略合成的NiFeOxHy-C/CNTs/CFP催化剂在电流密度10 mA cm-2条件下的过电位为202 mV, 稳定时间达到72 h, 表现出较好的水氧化性能.

扫描电子显微镜、透射电子显微镜、场发射透射电子显微镜和X射线衍射等结果表明, CNTs提高了催化剂的分散度, 从而暴露了更多的活性位点, 碳掺杂改变了催化剂的晶态, 导致催化剂无定形化. Raman光谱则证实了掺杂碳是以无定形碳和石墨碳的形态存在. 电化学阻抗谱结果表明, 碳界面修饰降低了催化剂和电解液之间的界面电荷传递电阻, 加速了水氧化反应的动力学.

除了界面电阻和电化学活性位点数量, 催化剂的电化学性能还与催化剂的电化学活性面积(ECSA)以及金属中心的电子结构密切相关. 与NiFe/CNTs/CFP催化剂相比, 催化剂NiFe-C/CNTs/CFP具有较低的活性面积和较高的几何活性, 也证实了碳掺杂提高了催化剂的本证活性. X射线光电子能谱和X射线吸收谱则提供了多碳界面修饰对催化剂电子结构变化的依据. 根据EXAFS拟合数据, 键长分别为2.301和2.578 Å的分裂峰归属于Fe-O-C配位层, 证实了金属Fe和碳材料之间存在很强的相互作用, 这种相互作用有助于提高催化剂的分散度, 并且减弱金属和金属之间的相互作用, 从而优化催化剂表面对中间态物种的化学吸附能.

为了考察NiFe-C/CNTs/CFP和NiFe/CNTs/CFP两种催化剂在OER反应中可能的机理, 本文测试了它们在不同pH条件下的极化曲线, 通过建立电流密度的对数值和pH之间的线性关系, 证实了两种催化剂的OER反应速控步骤均为去质子化过程. 另外, 根据Arrhenius方程计算结果表明, 在过电位为300 mV的条件下, NiFe/CNTs/CFP和NiFe-C/CNTs/CFP的OER反应活化能分别为16.8和11.2 kJ mol-1, 进一步证实了多碳界面修饰策略有效降低了水氧化反应的反应能垒. 综上, 本文为开发高效稳定的过渡金属水氧化电催化剂提供了新途径, 有助于进一步拓展碳复合材料在电催化OER反应中的应用.

关键词: 电催化剂, 析氧反应, 界面工程, 碳纳米管, 纳米复合物

Abstract:

Interface engineering has been widely investigated to regulate the structure and performance of electrodes and photoelectrodes, but the investigation of multiple carbon interface modifications on the electrocatalytic oxygen evolution reaction (OER) is still shortage. Herein, we report remarkable promotion of OER performance on the NiFe-based nanocomposite electrocatalyst via the synergy of multiple carbon-based interface engineering. Specifically, carbon nanotubes were in situ grown on carbon fiber paper to improve the interface between CFP and NiFeOxHy, and graphite carbon nanoparticles were in situ loaded and partly doped into the NiFeOxHy to modify the intergranular interface charge transfer and electronic structure of NiFeOxHy. Consequently, the as-obtained NiFeOxHy-C/CNTs/CFP catalyst exhibited significantly enhanced electrocatalytic OER activity with an overpotential of 202 mV at 10 mA cm-2 in 1 mol L-1 KOH. Our work not only extends application of carbon materials but also provides an alternative strategy to develop highly efficient electrocatalysts.

Key words: Electrocatalyst, Oxygen evolution reaction, Interface engineering, Carbon nanotube, Nanocomposite