Executive Summary : | The demand for green energy and storage systems is increasing, with supercapacitors being a promising solution due to their high charge-discharge rate, long life cycle, stability, and size. Metal oxides, such as RuO₂, are considered good electrode materials for supercapacitors due to their high stable specific capacitance, excellent reversibility, and long cycle life. However, their application is limited due to their high cost, toxicity, and less abundance. Cobalt oxide-based electrode materials have been considered promising for pseudocapacitors and asymmetrical supercapacitors due to their fast redox reactions, reversibility, high specific surface area, low-toxicity, abundance, stability, and theoretical capacity of about 3560 F g-1. However, their practical capacitance is far from theoretical due to slow electron kinetics, poor conductivity, fast capacity decay, ineffective porosity, and impaired morphologies during redox electrochemical reactions. To improve the specific capacitance of supercapacitors, researchers plan to develop a Co₃O₄ / NiCo₂O₄ heterostructure, which is more beneficial than a single layer. To address drawbacks of metal oxide-based electrodes, such as poor conductivity, low cycle life, and complexity in electrolyte ion penetration, the researchers will incorporate metal dopant and control pore architectures using a biomaterial template. Optimizing the ratio of Co₃O₄ / NiCo₂O₄ and metal dopant percentage will minimize oxidation and reduction peaks, enhance specific capacitance, life cycle, and capacity retention. The goal is to fabricate a low-cost asymmetric supercapacitor with Co₃O₄ / NiCo₂O₄ electrodes with various electrolytes and study their performance. |