FeN ₄ Sites Embedded into Carbon Nanofiber Integrated with Electrochemically Exfoliated Graphene for Oxygen Evolution in Acidic Medium

Journal Article · Sun Aug 05 00:00:00 EDT 2018 · Advanced Energy Materials

DOI:https://doi.org/10.1002/aenm.201801912· OSTI ID:1463188

Lei, Chaojun ^[1]; Chen, Hengquan ^[2]; Cao, Junhui ^[1]; Yang, Jian ^[1]; Qiu, Ming ^[3]; Xia, Ying ^[3]; Yuan, Chris ^[4]; Yang, Bin ^[1]; Li, Zhongjian ^[1]; Zhang, Xingwang ^[1]; Lei, Lecheng ^[1]; Abbott, Janel ^[5]; Zhong, Yu ^[6]; Xia, Xinhui ^[6]; Wu, Gang  ^[5]; He, Qinggang ^[2]; Hou, Yang  ^[1]

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1. Key Laboratory of Biomass Chemical Engineering of Ministry of Education College of Chemical and Biological Engineering Zhejiang University Hangzhou 310027 China
2. Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology College of Chemical &, Biological Engineering Zhejiang University Hangzhou Zhejiang 310027 China
3. Institute of Nanoscience and Nanotechnology College of Physical Science and Technology Central China Normal University Wuhan 430079 China
4. Department of Mechanical and Aerospace Engineering Case Western Reserve University 10900 Euclid Ave Cleveland OH 44106 USA
5. Department of Chemical and Biological Engineering University at Buffalo The State University of New York Buffalo NY 14260 USA
6. State Key Laboratory of Silicon Materials Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province School of Materials Science &, Engineering Zhejiang University Hangzhou 310027 China

Abstract Development of inexpensive and efficient oxygen evolution reaction (OER) catalysts in acidic environment is very challenging, but it is important for practical proton exchange membrane water electrolyzers. A molecular iron–nitrogen coordinated carbon nanofiber is developed, which is supported on an electrochemically exfoliated graphene (FeN ₄ /NF/EG) electrocatalyst through carbonizing the precursor composed of iron ions absorbed on polyaniline‐electrodeposited EG. Benefitting from the unique 3D structure, the FeN ₄ /NF/EG hybrid exhibits a low overpotential of ≈294 mV at 10 mA cm ⁻² for the OER in acidic electrolyte, which is much lower than that of commercial Ir/C catalysts (320 mV) as well as all previously reported acid transitional metal‐derived OER electrocatalysts. X‐ray absorption spectroscopy coupled with a designed poisoning experiment reveals that the molecular FeN ₄ species are identified as active centers for the OER in acid. The first‐principles‐based calculations verify that the FeN ₄ –doped carbon structure is capable of reducing the potential barriers and boosting the electrocatalytic OER activity in acid.

• Sponsoring Organization: USDOE
• OSTI ID: 1463188
• Journal Information: Advanced Energy Materials, Journal Name: Advanced Energy Materials Vol. 8 Journal Issue: 26; ISSN 1614-6832
• Publisher: Wiley Blackwell (John Wiley & Sons)
• Country of Publication: Germany
• Language: English