Co₃O₄ nanocrystals on graphene as a synergistic catalyst for oxygen reduction reaction

Nat Mater. 2011 Oct;10(10):780-6. doi: 10.1038/nmat3087.


Catalysts for oxygen reduction and evolution reactions are at the heart of key renewable-energy technologies including fuel cells and water splitting. Despite tremendous efforts, developing oxygen electrode catalysts with high activity at low cost remains a great challenge. Here, we report a hybrid material consisting of Co₃O₄ nanocrystals grown on reduced graphene oxide as a high-performance bi-functional catalyst for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Although Co₃O₄ or graphene oxide alone has little catalytic activity, their hybrid exhibits an unexpected, surprisingly high ORR activity that is further enhanced by nitrogen doping of graphene. The Co₃O₄/N-doped graphene hybrid exhibits similar catalytic activity but superior stability to Pt in alkaline solutions. The same hybrid is also highly active for OER, making it a high-performance non-precious metal-based bi-catalyst for both ORR and OER. The unusual catalytic activity arises from synergetic chemical coupling effects between Co₃O₄ and graphene.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Catalysis
  • Cobalt / chemistry*
  • Conservation of Energy Resources
  • Electrodes
  • Graphite / chemistry*
  • Kinetics
  • Nanoparticles / chemistry*
  • Nitrogen / chemistry
  • Oxidation-Reduction
  • Oxides / chemistry*
  • Renewable Energy


  • Oxides
  • Cobalt
  • Graphite
  • Nitrogen
  • cobalt oxide