A brief review of Nickel cobaltite nanostructures and its composites for supercapacitor application

Supercapacitors (SCs), recognized for their exceptional power and relatively high energy densities, long lifespan, and lower production costs, have emerged as an ideal solution to meet the growing demand for energy storage applications. The performance of supercapacitors is significantly influenced by the choice of electrode materials, making the development of novel materials a key focus in the field of high-performance supercapacitors. Recently, NiCo₂O₄ has attracted considerable attention as an electrode material due to its notable advantages including high theoretical capacity, low cost, natural abundance, easy of synthesis, and excellent electronic conductivity. However, the performance of NiCo₂O₄ is constrained by its low electrical conductivity and limited surface area, which lead to significant capacity degradation. This review article offers a comprehensive overview of the synthesis approaches employed to develop nickel cobaltite and its composites for supercapacitor applications. It details various synthesis methods, including sol-gel, hydrothermal, chemical bath deposition, and electrospinning techniques, with a focus on optimizing synthesis parameters to improve the electrochemical performance of these composites. The review concludes with future perspectives on the advancement of spinel NiCo₂O₄ for use as supercapacitor electrodes.