High-performance energy storage of highly saturated ferromagnetic cobalt-doped cuprous oxide thin films

Abstract

Pure and other concentrations of cobalt (Co2+) ions incorporated into cuprous oxide Cu2−xCoxO (x = 0–14 mM) thin films were successfully deposited in fluorine-doped tin oxide (FTO) glass substrate by employing electro deposition technique. The crystallite size of pure and Co-doped thin films was investigated from 29.03 to 43.38 nm using X-ray diffraction (XRD) patterns. Scanning electron microscope (SEM) images display three-sided pyramid shape morphology of pure Cu2O thin films that get significantly changed, as and when Co concentrations get increased. The optical bandgap value gets continuously increased from 2.128 to 2.297 eV for a 0–14 mM change in Co doping concentration. Vibrating sample magnetometer (VSM) pictures the film that exhibits a better ferromagnetic property with a saturation magnetism of 159.96 E−6 emu for 14 mM Co dopant. X-ray photoelectron spectroscopy (XPS) confirm the presence of cobalt (Co2+) as a dopant in the host Cu2O thin films. The Cu2−86Co14O (x = 14 mM) thin film has a higher specific capacitance of 164.90 F/g with 3.66 Wh/kg energy density at the current density of 2 A/g. It has a good energy and a power density in the higher concentration Co-doped Cu2O thin films applicable for energy storage devices.