Fe–N 4 engineering of S and N co-doped hierarchical porous carbon-based electrocatalysts for enhanced oxygen reduction in Zn–air batteries

• Published in: Dalton transactions : an international journal of inorganic chemistry 2020-11, Vol.49 (42), p.14847-14853
• Main Authors: Gao, Jingxia, Liu, Sa, Zhu, Ping, Zhao, Xinsheng, Wang, Guoxiang
• Format: Article
• Language: English
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/D0DT02704A

The development of high-performance non-noble metal cathode catalysts is a cutting-edge approach for efficient energy conversion and storage devices. Here, we describe an in situ -formed template-assisted method to prepare a highly active yet stable electrocatalyst (FeSN-HPC) that possesses abundant Fe–N 4 sites uniformly dispersed in S and N co-doped hierarchical porous carbon. Compared to commercial Pt/C in alkaline electrolyte, the sample FeSN-HPC displays superior and enhanced oxygen reduction reaction (ORR) activity (0.86 V of half-wave potential) and stability (only 14 mV degradation of half-wave potential after durability tests). The high electrocatalytic activity of FeSN-HPC mainly originates from the synergistic effect of efficient N dopants (such as pyridinic N, graphitic N, and Fe II –N 4 ) and the desirable hierarchical porous architecture. Expectedly, the primary Zn–air battery (ZAB) with FeSN-HPC as the cathode electrocatalyst exhibits an outstanding discharge performance, with a maximal power density of 200 mW cm −2 . Additionally, the sample FeSN-HPC also has promising potential for application in solid and flexible ZABs.