Hierarchical nanostructured NiCo2O4 as an efficient bifunctional non-precious metal catalyst for rechargeable zinc-air batteries

Nanoscale. 2014 Mar 21;6(6):3173-81. doi: 10.1039/c3nr05835b. Epub 2014 Feb 5.

Abstract

A nickel-doped cobalt oxide spinel structure is a promising non-precious metal electrocatalyst for oxygen evolution and oxygen reduction in rechargeable metal-air batteries and water electrolyzers operating with alkaline electrolytes. One dimensional NiCo2O4 (NCO) nanostructures were prepared by using a simple electrospinning technique with two different metal precursors (metal nitrate/PAN and metal acetylacetonate/PAN). The effect of precursor concentration on the morphologies was investigated. Single-phase, NCO with an average diameter of 100 nm, porous interconnected fibrous morphology was revealed by FESEM and FETEM analysis. The hierarchical nanostructured 1D-spinel NiCo2O4 materials showed a remarkable electrocatalytic activity towards oxygen reduction and evolution in an aqueous alkaline medium. The extraordinary bi-functional catalytic activity towards both ORR and OER was observed by the low over potential (0.84 V), which is better than that of noble metal catalysts [Pt/C (1.16 V), Ru/C (1.01 V) and Ir/C (0.92 V)], making them promising cathode materials for metal-air batteries. Furthermore, the rechargeable zinc-air battery with NCO-A1 as a bifunctional electrocatalyst displays high activity and stability during battery discharge, charge, and cycling processes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Air*
  • Catalysis
  • Cobalt / chemistry*
  • Electric Power Supplies*
  • Electrochemical Techniques
  • Electrodes
  • Nanostructures / chemistry*
  • Nickel / chemistry*
  • Oxides / chemistry*
  • Porosity
  • Zinc / chemistry*

Substances

  • Oxides
  • Cobalt
  • Nickel
  • nickel monoxide
  • Zinc
  • cobalt oxide