Fabrication of three-dimensional porous cobalt network-supported cobalt oxides nanoflake arrays for electrochemical energy storage

Abstract

Smart combination of porous metal with metal oxides is important for the construction of high-performance electrochemical devices. Herein, we report three-dimensional Co network-supported Co₃O₄ nanoflake arrays by a facile electrodeposition and following hydrothermal process. 3D Co networks with porous branches and interconnected pores are well formed and used as the skeleton for the growth of porous Co₃O₄ nanoflake arrays. High porosity and integrated growth are combined in the composite electrode. As an anode material for lithium ion batteries, the Co network-supported Co₃O₄ nanoflake array electrode exhibits a high first discharge capacity (1164 mAh g⁻¹ at 0.5 A g⁻¹), good cycling stability (714 mAh g⁻¹ after 100 cycles) and enhanced rate capability. The proposed method is useful for the construction of other porous metal/metal oxide composite films for application in electrochemical energy storage and catalysis.

Keywords:

• Cobalt oxides
• Thin films
• Nanostructures
• Energy storage
• Electrochemical properties