The formation of CuO and CuO microstructures using localized electrochemical deposition was studied and its potential as supercapacitor electrodes were investigated for the first time. X-ray diffraction analysis showed that heat treatment of the resulting material at 100°C in air results in the formation of a copper(I) oxide film, while at 400°C, oxidation of the material occurs, yielding CuO. Scanning electron microscopy data indicate that the formed oxide pixels have a diameter of approximately 350 μm. It was determined that, with the longest contact time between the substrate and the meniscus of the reaction system under applied voltage, the resulting film is characterized by a dendritic, hierarchically organized microstructure. The primary particles are organized into elongated structures, which in turn form two-dimensional fractal-like CuO agglomerates. Atomic force microscopy was used to determine the maximum height difference for the oxide structures. Kelvin probe force microscopy was used to estimate the electron work function of the film surfaces. Electrochemical measurements were conducted on the formed materials in an aqueous potassium hydroxide solution. It was shown that the CuO film exhibits a 1.6-fold higher specific capacitance than the CuO film at a current density of 1 mA/cm². Impedance spectroscopy also revealed that the CuO film exhibits lower resistance.
N. P. Simonenko (Wed,) studied this question.