Bifunctional oxygen catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) with high activities and low‐cost are of prime importance and challenging in the development of fuel cells and rechargeable metal–air batteries. This study reports a porous carbon nanomaterial loaded with cobalt nanoparticles (Co@NC‐
Developing high performance nonprecious metal‐based electrocatalysts has become a critical first step towards commercial applications of metal‐air batteries. Herein, nanocomposites based on Co/Co2P nanoparticles encapsulated within hierarchically porous N, P, S co‐doped carbon are prepared by controlled pyrolysis of zeolitic imidazolate frameworks (ZIF‐67) and poly(cyclotriphosphazene‐co‐4,4’‐sulfonyldiphenol) (PZS). The resulting Co/Co2P@NPSC nanocomposites exhibit apparent oxygen reduction reaction (ORR) and evolution reaction (OER) catalytic performance, and are used as the reversible oxygen catalyst for zinc‐air batteries (ZABs). Density functional theory (DFT) calculations exhibit that Co2P could provide active sites for the ORR and promote the conversion between the adsorbed intermediates, and porous N,P,S co‐doped carbon with Co2P nanoparticles also improves the exposure of actives sites and endows charge transport. Liquid‐state ZABs with Co/Co2P@NPSC as the cathode catalysts demonstrate the greater power density of 198.1 mW cm−2and a long cycling life of 50 h at 10 mA cm−2, likely due to the encapsulation of Co/Co2P nanoparticles by the carbon shell. Solid‐state ZABs also display a remarkable performance with a high peak power density of 74.3 mW cm−2. Therefore, this study indicates the meaning of the design and engineering of hierarchical porous carbon nanomaterial as electrocatalyst for rechargeable metal‐air batteries.
more » « less- NSF-PAR ID:
- 10360479
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemElectroChem
- Volume:
- 8
- Issue:
- 22
- ISSN:
- 2196-0216
- Page Range / eLocation ID:
- p. 4286-4295
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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