Single-thermal synthesis of bimetallic Co/Zn@NC under solvent-free conditions as an efficient dual-functional oxygen electrocatalyst in Zn-air batteries

Zechen Wang; Xiaotong Hou; Sander Dekyvere; Bibimaryam Mousavi; Somboon Chaemchuen

doi:10.1039/d2nr03997d

Single-thermal synthesis of bimetallic Co/Zn@NC under solvent-free conditions as an efficient dual-functional oxygen electrocatalyst in Zn-air batteries

Nanoscale. 2022 Nov 17;14(44):16683-16694. doi: 10.1039/d2nr03997d.

Authors

Zechen Wang^{1

2}, Xiaotong Hou^{1

2}, Sander Dekyvere^{1

2}, Bibimaryam Mousavi¹, Somboon Chaemchuen¹

Affiliations

¹ State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan, China. sama_che@hotmail.com.
² School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, P. R. China.

PMID: 36331371
DOI: 10.1039/d2nr03997d

Abstract

A straightforward in situ thermal (IST) method is developed to synthesize bimetallic Co/Zn embedded in nitrogen-doped three-dimensional carbon (CoZn@NC_IST). The facile IST process is a single-step thermal treatment of a mixture of metals (Co/Zn) and 2-methylimidazole precursors under solvent-free conditions. This straightforward method is advantageous over the traditional synthesis derived from CoZn-ZIF (CoZn@NC_Solv). During the IST method, the bimetallic Co/Zn bridged with 2-methylimidazole forming zeolitic-imidazole frameworks (ZIFs) under low-temperature (<200 °C) conditions before being de-coordinated and sacrificed their structure into a carbon material at high temperature (>500 °C). Loading zinc into the mixture of precursors contributed to the metal distribution and increased the surface area compared with the sample without zinc (Co@NC_IST). CoZn@NC_IST exhibits a bifunctional electrocatalytic ability for the ORR (0.855 V@E_1/2) and OER (overpotential of 325 mV@10 mA cm^-2). Applying CoZn@NC_IST in a zinc-air battery confirmed its excellent and effective dual-function electrocatalytic performance. Herein, using the advanced single-step method of IST in the absence of any solvent, we provide a powerful and green synthesis of an electrocatalyst that is a potential candidate for industrial applications.