Single atom Fe-based catalyst derived from hierarchical (Fe, N)-ZIF-8/CNFs for high-efficient ORR activity. (21st September 2022)

• Record Type: Journal Article
• Authors: Miao, Wenfang; Huang, Feirong; Shen, Xiaochen; Li, Shaopeng; Cao, Xingru; Zhang, Xuefeng; Yu, Jieyi; Dong, Xinglong
• Is Part Of: Materials chemistry frontiers. Volume 6:Number 21(2022)
• Page Start: 3213
• Page End: 3224
• Publication Date: 2022-09-21
• Subjects: Materials science -- Periodicals; Chemistry -- Periodicals; 540
• DOI: 10.1039/d2qm00763k
• Languages: English
• ISSNs: 2052-1529

Abstract

Abstract : (i) The three-dimensional conductive network of CNFs improves intrinsic activity. (ii) Fe–Phen complex encapsulated in ZIF-8 provides atomically dispersed FeN x sites. (iii) Hierarchical Fe–N x –CNFs presents excellent ORR performance. Abstract : The development of high-efficiency, stable, and low-cost Fe–N–C electrocatalysts for the oxygen reduction reaction (ORR) has attracted considerable attention. Herein, a stable atomically dispersed Fe–N x -based catalyst was synthesized from a hierarchical structure involving carbon nanofiber (CNF)-supported zeolitic-imidazolate-framework-8 (ZIF-8) encapsulated Fe–Phen complex ((Fe, N)-ZIF-8/CNFs). The Fe–N x –CNFs obtained from the pyrolysis of (Fe, N)-ZIF-8/CNFs showed a good hierarchical multi-layer structure. The natural network structure of the carbon nanofibers serves as a matrix to uniformly distribute the ZIF-8 particles, and the Fe–N x sites derived from the Fe–Phen complex were uniformly distributed in ZIF-8 particles. It exhibits excellent ORR performance with a high half-wave potential of 0.875 V ( vs. RHE), which was 55 mV higher than that of the commercial Pt/C catalyst. In addition, density functional theory (DFT) calculations on the catalyst further revealed the origin of the ORR activity via a 4e − pathway from the precise local coordination of FeN4 sites.