Journal of Power Sources, Vol.194, No.2, 1194-1201, 2009
Facile approach to prepare loose-packed cobalt hydroxide nano-flakes materials for electrochemical capacitors
Cobalt hydroxide nano-flakes are successfully synthesized by a facile chemical precipitation method. Electrochemical characterization is performed using cyclic voltammetry. chronopotentiometry and impedance spectroscopy, respectively. These cobalt hydroxide nano-flakes maintain high utilization at high rates of discharge. A maximum specific capacitance of 735 Fg(-1) can be achieved in 2 M aqueous KOH with the potential range from -0.2 to 0.4V (vs. SCE) in a half-cell setup configuration for the nano-flakes Co(OH)(2) electrode, suggesting its potential application in electrochemical capacitors. Furthermore, the effect of annealing temperatures on the electrochemical capacitance characteristics is also been systematically explored. (C) 2009 Elsevier B.V. All rights reserved.
Keywords:Electrochemical capacitors;Cobalt hydroxide;Specific capacitance;Nano-flakes;Pseudo-capacitance