Dispersed cobalt nanoparticles in the nitrogen doped carbon black as efficient catalysts for oxygen reduction reaction and Zinc-Air batteries

Developing an effective and durable Pt-free oxygen reduction reaction (ORR) catalyst for Zinc-Air batter-ies (ZABs) is propitious to easing the energy and pollution crisis. Herein, we have prepared Co nanopar-ticles/N-doped carbon (Co/N/C) with tunable Co contents by the pyrolysis of polydopamine-coated cobalt phthalocyanine/carbon black precursors. Benefiting from the well-dispersed Co nanoparticles and the formation of various active sites (i.e. pyridinic, graphitic N and Co-Nx), the resulting Co/N/C-2.86 wt% cat-alysts possess a half-wave potential of 0.84 V and a mass activity of 5.18 A/g, illustrating the superior ORR performance. Noteworthy, the ZABs with the cathode of Co/N/C-2.86 wt% display an outstanding cell per-formance with a large open-circuit voltage (1.542 V), a high specific discharge capacity (744 mAh g-1) and an excellent maximum power density (236 mW cm2). This work offers a promising approach to rationally design and fabricate high-performance ORR electrocatalysts for advanced ZABs. CO 2023 Elsevier Ltd. All rights reserved.

Automated summary

Developing an effective and durable Pt-free oxygen reduction reaction (ORR) catalyst is crucial for alleviating the energy and pollution crisis. In this study, Co nanoparticles/N-doped carbon (Co/N/C) with tunable Co contents were synthesized, leading to superior ORR performance with a half-wave potential of 0.84 V and a mass activity of 5.18 A/g. Furthermore, the Co/N/C-2.86 wt% catalyst exhibited outstanding cell performance in Zinc-Air batteries (ZABs) with a high open-circuit voltage, specific discharge capacity, and maximum power density. This work provides a promising approach for designing high-performance ORR electrocatalysts for advanced ZABs.