Facile synthesis of KV₃O₈ nanobelts for solid-state supercapacitors

Electrochemical supercapacitors emerge as promising energy storage systems for various electronic applications owing to their low cost, safe operation, and long lifespan. However, the limited choice of cathode materials and lack of green and scalable synthesis strategies largely hinder their practical applications. Herein, we describe a facile ultrasonic-assisted chemical method for synthesizing potassium vanadate (KV₃O₈) nanobelt as cathode material for asymmetric supercapacitor application. It demonstrates excellent electrochemical performance in terms of high-rate capability, specific capacitance, operating voltage (1.8 V), and energy density (51 Wh kg⁻¹). This work provides a new strategy for fabricating high-performance electrode material using a simple and low-cost ultrasonic-assisted chemical method which is highly efficient and suitable for large-scale production to develop advanced energy storage devices. By addressing the key challenges in the field, this study contributes to the advancement of sustainable and efficient energy storage solutions.