Controllable synthesis of mesoporous Co3O4 nanoflake array and its application for supercapacitor

Abstract

A mesoporous Co3O4 nanoflake array grown on carbon cloth is prepared by a facile electrodeposition method with a following annealing process. The as-prepared Co3O4 nanoflake possesses a continuous mesopores ranging from 2 to 5nm and grows tightly on the substrate forming a porous net-like structure with macropores of 20–200nm. The electrochemical performance of the mesoporous Co3O4 nanoflake arrays as pseudocapcitor electrode are investigated by cyclic voltammograms and galvanostatic charge/discharge tests in 2M KOH. The as-prepared Co3O4 array exhibits a high discharge capacitance and excellent rate capability with 450Fg−1, 436Fg−1, 408Fg−1, 380Fg−1and 363Fg−1 at 1, 2, 4, 10, and 20Ag−1, respectively. The specific capacitance of 81% is maintained from 1Ag−1 to 20Ag−1. The electrode also shows rather good cycling stability and exhibits a specific capacitance of 414Fg−1 after 5000 cycles.