Cobalt nanoparticles/nitrogen, sulfur-codoped ultrathin carbon nanotubes derived from metal organic frameworks as high-efficiency electrocatalyst for robust rechargeable zinc-air battery

It remains a challenge for efficient and facile synthesis of promising non-noble metal electrocatalysts with outstanding properties. This work reported a simple pyrolysis method to prepare cobalt nanoparti-cles/nitrogen, sulfur-codoped ultrathin carbon nanotubes (Co NPs/N,S-CNTs) with metal organic frame-works (cobalt 2-methylimidazole, ZIF-67), melamine, polyvinylpyrrolidone (PVP) and thiourea. The prepared catalyst exhibited superior catalytic activity towards oxygen reduction reaction (ORR) such as the more positive onset potential of 0.96 V, half-wave potential of 0.86 V and smaller Tafel slope of 67.9 mV dec(-1), outperforming those of commercial Pt/C. Furthermore, the Co NPs/N,S-CNTs based Zn-air battery not only showed good cycling performance, but also displayed a notable peak power density (153.8 mW cm(-2)) and large open-circuit voltage (1.433 V). This study provides some valuable guidelines for synthesizing advanced electrocatalysts in renewable energy techniques. (C) 2021 Elsevier Inc. All rights reserved.

Automated summary

This work reported a simple pyrolysis method to prepare cobalt nanoparticles/nitrogen, sulfur-codoped ultrathin carbon nanotubes with outstanding catalytic activity towards oxygen reduction reaction, as well as good performance in Zn-air batteries.