<p>The inspiration for the development of specific nanophase materials comes from increasing energy needs of the future. This study presents the fabrication technique and assesses the performance of a supercapacitor electrode composed of manganese-cobalt (MnCo₂O₄) integrated within graphitic carbon nitride (g-CN). X-ray diffraction investigation revealed that the MnCo₂O₄ phase included a cubic crystal structure. Scanning electron microscopy of MnCo₂O₄/g-CN reveals porous heterostructure morphology, while Brunauer–Emmett–Teller analysis indicates a specific surface area of 113 m²&#xa0;g⁻¹, suggesting abundant active sites and enhanced electrochemical accessibility. The hydrothermal-assisted nanohybrid demonstrated a significant enhancement in specific capacitance (<i>C</i>_s), along with exceptional durability. MnCo₂O₄/g-CN nanocomposite had a specific capacity (<i>Q</i>_s) of 476 C g⁻¹ at 1 A g⁻¹. The MnCo₂O₄/g-CN//AC ASC device exhibits&#xa0;energy density (47.6Wh kg⁻¹) and power density (600 W kg⁻¹). The presence of varied manganese oxidation states, a significant specific surface area (SSA), and mesoporous quality, which allows rapid ion movement, all contributed to improved electrochemical functionality. The inclusion of electrochemically active patches inside the g-CN sheet design influenced its electrochemical characteristics. According to their results, adopting the MnCo₂O₄/g-CN nanohybrid for application as an electrode in energy storage seems like an affordable choice.</p>