Sustainable fabrication of Fe₂O₃/C nanoparticles via Acacia nilotica extract for enhanced supercapacitor performance

This research investigates the eco-friendly production of iron oxide nanoparticles and their combination with carbon to create the FeC-1 and FeC-2 NPs, using seedless pods of<i>Acacia nilotica</i>. These pods, rich in tannins and flavonoids, serve as a natural reducing, stabilizing, and carbon source. The study details the synthesis of FeC NPs through a non-toxic, green method and examines the influence of varying concentrations of<i>A. nilotica</i>extract (ANE) on the electrochemical characteristics of the resulting n FeC-1 and FeC-2 electrodes. Both FeC-1 and FeC-2 NPs were tested extensively using cyclic voltammetry and galvanostatic charge-discharge methods to evaluate their pseudocapacitive properties in a three-electrode setup. The FeC-2 electrodes showed much better performance, achieving a specific capacitance of 482.85 F g^-1, compared to FeC-1's 155.71 F g^-1. This enhanced capacity is attributed to an optimal content that notably boosts conductivity. Additionally, FeC-2 showed impressive cyclic stability, retaining approximately 80% capacity at a constant current density. These findings underscore the potential of using ANE for developing cost-effective and environmentally benign FeC-1 and FeC-2 NPs with promising applications in high-performance supercapacitors.