Materials Research Bulletin, Vol.74, 472-477, 2016
Controllable synthesis of cobalt oxide nanoflakes on three-dimensional porous cobalt networks as high-performance cathode for alkaline hybrid batteries
Herein we report porous three-dimensional cobalt networks supported CoO nanoflakes by the combination of successive electro-deposition methods. The electrodeposited Co networks have average large pores of similar to 5 mu m and all the branches are composed of interconnected nanoparticles. CoO nanoflakes with thickness of similar to 15 mu m are uniformly coated on the Co networks forming self-supported Co/CoO composite films. The as-prepared Co/CoO composite films possess combined properties of porous structure and strong mechanical stability. As cathode for alkaline hybrid batteries, the Co/CoO composite films exhibit good electrochemical performances with high capacity of 83.5 mAh g(-1) at 1 A g(-1) and stable high-rate cycling life (65 mAh g(-1) at 10 A g(-1) after 15,000 cycles). The hierarchical porous architecture provides positive roles in the enhancement of electrochemical properties, including fast electronic transportation path, short diffusion of ions and high contact area between the active material and the electrolyte. (C) 2015 Elsevier Ltd. All rights reserved.