Atomically dispersed Fe-N-C derived from dual metal-organic frameworks as efficient oxygen reduction electrocatalysts in direct methanol fuel cells

• Published in: Applied catalysis. B, Environmental Environmental, 2019-12, Vol.259, p.118042, Article 118042
• Main Authors: Xu, Xinlong, Xia, Zhangxun, Zhang, Xiaoming, Sun, Ruili, Sun, Xuejing, Li, Huanqiao, Wu, Chuchu, Wang, Junhu, Wang, Suli, Sun, Gongquan
• Format: Article
• Language: English
• Subjects: Absorption spectroscopy; Atomically dispersed Fe atoms; Catalysts; Chemical reduction; Commercialization; Direct methanol fuel cells; Electrocatalysts; Fuel cells; Fuel technology; Iron; Metal-organic frameworks; Methanol; Nitrogen; Nitrogen sources; Oxygen; Oxygen reduction reaction; Oxygen reduction reactions; Pyrolysis; Spectrum analysis; X ray absorption; X-ray absorption spectroscopy
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2019.118042

Atomically dispersed Fe-N-C catalyst is fabricated by a rational designed dual-MOFs strategy for efficient and low-cost DMFC application. [Display omitted] •A dual-MOFs strategy is developed for the fabrication of atomically dispersed Fe-N-C catalyst.•The formation mechanism of the atomically dispersed Fe-N-C catalyst is well investigated.•The as-prepared catalyst demonstrates high ORR activity, excellent methanol tolerance and outstanding stability in acids.•The DMFC assembled with atomically dispersed Fe-N-C catalyst exhibits excellent performance. The rational design of highly efficient, low-cost and methanol-tolerant catalysts toward the oxygen reduction reaction (ORR) is urgently desired for the commercialization of direct methanol fuel cells (DMFCs). Herein, a novel Fe-N-C catalyst (ZIF/MIL-10-900) is derived from a mixture of ZIF-8 and MIL-101(Fe) and atomically dispersed FeN4 structures are confirmed by Mössbauer spectra and X-ray absorption spectroscopy. Study on the pyrolysis procedure reveals that Fe atoms in FeN4 are from MIL-101(Fe), while ZIF-8 acts as structural support and nitrogen sources. The as-prepared catalyst demonstrates a comparable ORR activity with the commercial Pt/C possessing a half-wave potential (E1/2) of 0.78 V in acids, in combination with excellent methanol tolerance and stability. One of the highest peak power density of 83 mW cm−2 in DMFC (3 M CH3OH) by adopting ZIF/MIL-10-900 as cathode catalyst is obtained, which is 2.8-fold higher than that of the commercial Pt/C in the same operating condition.