Rich atomic interfaces between sub-1 nm RuOx clusters and porous Co3O4 nanosheets boost oxygen electrocatalysis bifunctionality for advanced Zn-air batteries

Qian Lu, Yanan Guo, Peng Mao, Kaiming Liao, Xiaohong Zou, Jie Dai, Peng Tan, Ran Ran, Wei Zhou, Meng Ni, Zongping Shao

Research output: Journal article publicationJournal articleAcademic researchpeer-review

15 Citations (Scopus)

Abstract

The practical use of Zn-air batteries (ZABs) is strongly dependent on the availability of bifunctional oxygen electrocatalysts that should have high activity and durability for both oxygen evolution/reduction reactions (OER/ORR) in alkaline solution. Herein, we report the design of a new Ru-based bifunctional catalyst characterized with rich atomic interfaces through the in-situ growth of sub-1nm RuOx clusters on the surface of porous Co3O4 nanosheets with 4.1 ​wt% Ru loaded. Such unique architecture ensures the creation of high-energy interfacial Ru-O-Co bond that allows fine tuning of the electronic structure of both Ru and Co. The as-prepared catalyst exhibits superior oxygen electrocatalysis bifunctionality, indicated by an ultralow potential gap of 0.71 ​V between the potential of OER at 10 ​mA ​cm-2 (1.51 ​V) and the half-wave potential for ORR (0.80 ​V). Remarkably, rechargeable ZAB with such electrocatalyst demonstrates not only high rate performance (50 ​mA ​cm−2) and power density (150 ​mW ​cm-2), but also superior round-trip efficiency (68.4%, after 250 ​h). X-ray photoelectron and Raman spectroscopy reveal that the active sites for ORR/OER are mainly the unsaturated trivalence Ru in RuOx clusters, and the formed interfacial Ru-O-Co bond can avoid the dissolution of RuOx in alkaline electrolyte, holding great potential in implementation of long-life rechargeable ZABs.

Original languageEnglish
Pages (from-to)20-29
Number of pages10
JournalEnergy Storage Materials
Volume32
DOIs
Publication statusPublished - Nov 2020

Keywords

  • Atomic interface
  • Bifunctional electrocatalyst
  • Ru-O-Co bond
  • RuO cluster
  • Zn-air battery

ASJC Scopus subject areas

  • Renewable Energy, Sustainability and the Environment
  • Materials Science(all)
  • Energy Engineering and Power Technology

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