Three-dimensional nanoscale Co₃O₄ electrode on ordered Ni/Si microchannel plates for electrochemical supercapacitors

Nanoscale cobalt oxide (Co₃O₄) particles are produced on three-dimensional nickel/silicon microchannel plates (Ni/Si-MCPs) as the active electrode materials in miniature supercapacitors. The Co ₃O₄ nano-flakes are fabricated on the surface and interior of the Ni/Si-MCPs by annealing the nano-structured Co(OH)₂/Ni/Si- MCPs, and the electrical conductivity and capacitance retention are improved. The Ni/Si-MCPs covered with nano-flaked Co₃O₄ supercapacitor offer smaller charging current leakage and higher discharging voltage than Ni/Si-MCPs electrodeposited with cobalt hydroxide {Co(OH)₂}. Specific capacitance as high as 2.424 F/cm² or 606.24 F/g is achieved from the materials and the retention ratio is 89.85% after 2000 cycles thus demonstrating excellent potential in miniature supercapacitors. © 2014 Elsevier B.V. All rights reserved.