Effects of the electrodeposition potential and temperature on the electrochemical capacitance behavior of ordered mesoporous cobalt hydroxide films

Novel ordered mesoporous cobalt hydroxide film (designated HI-e Co(OH)2) has been successfully electrodeposited from cobalt nitrate dissolved in the aqueous domains of the hexagonal lyotropic liquid crystalline phase of Brij 56. Experimental electrodeposition parameters such as deposition potentials and deposition temperatures are varied to analyze their influences on the electrochemical capacitor behavior. The films are physically characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to determine the effects of deposition potentials and temperatures on the surface morphology and nanostructure. Electrochemical techniques such as cyclic voltammetry (CV) and chronopotentiometry are applied to systematically investigate the effects of deposition potentials and temperatures on the capacitance of the films. The results demonstrated that the capacitive performance of the HI-e Co(OH)2 film achieved the highest value when it is electrodeposited at −0.75 V under the deposition temperature of 50 °C.