FeNx and γ-Fe2O3 co-functionalized hollow graphitic carbon nanofibers for efficient oxygen reduction in an alkaline medium. Issue 12 (16th March 2020)

• Record Type: Journal Article
• Authors: Yu, Qiang; Lian, Sitian; Li, Jiantao; Yu, Ruohan; Xi, Shibo; Wu, Jinsong; Zhao, Dongyuan; Mai, Liqiang; Zhou, Liang
• Is Part Of: Journal of materials chemistry. Volume 8:Issue 12(2020)
• Page Start: 6076
• Page End: 6082
• Publication Date: 2020-03-16
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d0ta00073f
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : FeN x and γ-Fe2 O3 nanoparticle co-functionalized hollow graphitic carbon nanofibers exhibit desirable ORR electrocatalytic activity. Abstract : The exploration of efficient, stable, and inexpensive oxygen reduction reaction (ORR) electrocatalysts to replace Pt/C in fuel cells and metal–air batteries still remains an ongoing challenge. Herein, we report an efficient ORR electrocatalyst composed of single-atom FeN x and γ-Fe2 O3 nanoparticle co-functionalized hollow graphitic carbon nanofibers (FeN x /Fe2 O3 -CNFs). It is found that the FeN x species serve as the active sites, while the γ-Fe2 O3 nanocrystals function as a co-catalyst to boost the ORR catalytic activity. The obtained FeN x /Fe2 O3 -CNFs exhibit desirable ORR electrocatalytic activity with a 4-electron transfer pathway, a half-wave potential of 0.81 V approaching that of commercial Pt/C, low hydrogen peroxide yields (<6% at 0.2–0.7 V), long-term stability (87.14% after 30 000 s), and excellent methanol tolerance. The assembled Zn–air battery based on the FeN x /Fe2 O3 -CNFs has an open circuit voltage of 1.51 V and superior energy density of 920 W h kg −1 . This work highlights the significant contribution of the co-catalyst in electrocatalysis.