Preparation of Co[sbnd]N co-doped carbon nanosheets electrocatalyst for efficient oxygen reduction reaction in zinc-air battery

Abstract

It is very vital that there be a high-activity and serviceable catalyst for the oxygen reduction reaction (ORR) in the Zn-air Battery. Herein, utilizing g-C3N4 as a self-sacrifice template and Cobalt-His framework as the precursor, a simple strategy was developed to synthesize Co/N co-doped carbon nanosheets (CoNC 800) as a metal electrocatalyst for ORR. Due to the Co/N co-doped CoNX site and large specific surface area, the acquired materials show a preeminent ORR catalytic activity with an initial potential (~0.96 V) and half-wave potential (E1/2) of 0.85 V (vs. RHE) in an alkaline medium. Most importantly, the material has superior long-term stability and methanol tolerance than Pt/C. Furthermore, we assembled the Zn-air battery employing catalyst as an air cathode catalyst, demonstrating maximum power densities of 144 mWcm−2, a specific capacity of 821.50 Wh·kg−1, and charge/discharge cycle stability of more than 140 h. The nanosheet structure electrocatalysts derived from the Cobalt-His framework and g-C3N4 provide an innovative and instructive approach to the design of diverse nanomaterials.