Abstract
This work presents an efficient method for synthesising arrays of copper oxide (CuO) nanocrystals in track-etched dielectric structures via electrochemical deposition (ECD) and provides a comprehensive study of their structural, morphological, and optical properties. Electrochemical deposition was performed in a carefully selected electrolyte under a potentiostatic regime, enabling reproducible and selective filling of the nanocanals within the track matrix. The template consisted of a porous silicon dioxide structure formed by ion irradiation followed by etching. The ECD method is characterised by technological simplicity, low energy consumption, environmental safety, the absence of high-temperature annealing and expensive vacuum equipment requirements, and the possibility of deposition on substrates with complex geometries. The surface morphology and pore topography were analysed using scanning electron microscopy (SEM), while the phase composition and crystal structure of the deposited material were confirmed by X-ray diffraction (XRD), revealing the formation of a monoclinic CuO phase (space group C2/c). Photoluminescence studies revealed emission peaks in the 3.11–3.22 eV range, corresponding to the violet region of the spectrum. These peaks are attributed to interband transitions and recombination of charge carriers via localised defect states in the CuO crystal structure. The influence of pore geometry and deposition conditions on the distribution and quality of channel filling was also highlighted. The obtained results demonstrate the potential of the proposed approach for creating functional CuO nanostructures with tailored properties and geometry. The developed methodology can be applied in the fabrication of sensor systems, photonic electronic components, and energy-efficient devices based on transition metal oxides.