Hydrothermally Synthesized Cobalt-Doped NiO Nanoflakes: Enhanced Electrochemical Performance for High-Performance Supercapacitors

This study examines cobalt-doped nickel oxide (Co-NiO) nanomaterials synthesized through a hydrothermal method, focusing on their potential as high-performance electrodes for supercapacitors. By varying cobalt dopant concentrations (X=0, 0.01, 0.05, 0.1), we aimed to enhance the electrochemical properties through strategic Co-doping. The Co_xNi_1-xO nanomaterials were characterized using several techniques, including X-ray diffraction (XRD), UV-visible spectroscopy, field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), chronopotentiometry (CP), and electrochemical impedance spectroscopy (EIS). The analysis showed that Co-doping preserved the NiO phase structure while significantly altering the morphology and electrochemical characteristics. The sample with (X=0.1) achieved a specific capacitance of 880 F/g at a current density of 1 A/g, significantly outperforming the undoped NiO, which had a capacitance of 335 F/g. Additionally, the Co-NiO demonstrated 83.3 % capacitance retention after 1000 cycles at a current density of 10 A/g. These findings highlight the potential of Co-NiO as an effective electrode material for supercapacitors.