Bifunctional mesoporous CoO/nitrogen-incorporated graphene electrocatalysts for high-power and long-term stability of rechargeable zinc-air batteries

Tae Ho Park, Jeong Seok Yeon, Periyasamy Sivakumar, Youngkwon Kim, Ho Seok Park

Research output: Contribution to journalArticlepeer-review

12 Scopus citations

Abstract

Despite high energy density, low-cost, and ecofriendly, rechargeable Zinc-air batteries (ZABs) suffer from sluggish kinetics stability during oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) at the cathode. Herein, we demonstrate CoO nanoparticles anchored on N-doped reduced graphene oxide (CoO/N-rGO) with an excellent bifunctional catalytic activity and stability and facile redox kinetics of ORR and OER for high-performance rechargeable ZABs. The CoO/N-rGO catalysts are featured with the abundant active sites, a large accessible area, and high electrochemical conductivity, which are associated with increased oxygen vacancy surface, reduced valence, and mesoporous architecture. The half-wave potential (E1/2) and electron transfer number for ORR are 0.79 V and 3.72 at 0.40 V (vs RHE), respectively, while OER potential at 10 mA cm−2 (Ej = 10) is 1.61 V (vs RHE). Remarkably, the ZAB cell with CoO/N-rGO achieves high specific capacity of 545 mAh gzn−1, power density of 41 mW cm−2, and cyclic stabilities with high energy efficiency of 64.44% at 2 mA cm−2. In addition, postmortem analysis validates that the oxidation and aggregation of CoO/N-rGO catalyst is mitigated while the inactivation of Zn anode is inhibited.

Original languageEnglish
Pages (from-to)6698-6707
Number of pages10
JournalInternational Journal of Energy Research
Volume45
Issue number5
DOIs
StatePublished - Apr 2021
Externally publishedYes

Bibliographical note

Publisher Copyright:
© 2020 John Wiley & Sons Ltd

Keywords

  • bifunctional catalysts
  • cobalt monoxide
  • mesoporous structure
  • nitrogen doping
  • zinc-air batteries

Fingerprint

Dive into the research topics of 'Bifunctional mesoporous CoO/nitrogen-incorporated graphene electrocatalysts for high-power and long-term stability of rechargeable zinc-air batteries'. Together they form a unique fingerprint.

Cite this