A study on eco-friendly method for the synthesis of novel ternary NiMn₂O₄/TiO₂-chitosan nanocomposite for the improvement of electrochemical performance

In this work, a sustainable and cost-effective approach was developed to synthesize a ternary composite (NiMn2O4/TiO2-Chitosan) via an eco-friendly method using coconut cotyledon extract as a reducing agent. This environmentally friendly synthesis route successfully developed a nanocomposite with distinct structural and morphological characteristics. XRD analysis confirmed the formation of a highly crystalline phase, while FESEM revealed mixed and irregular morphologies. EDAX spectrum qualitatively verified the presence of Ni, Mn, Ti, C and O in the composite. HRSTEM further displayed a disordered cubic structure, indicating nanoscale complexity. The optical band gap of the composite was determined to be 2.93eV, suggesting potential for semiconducting applications. Electrochemical evaluation in a three-electrode system using KOH electrolyte demonstrated a remarkable specific capacitance of 1089.41F g⁻¹ at a current density of 1mA g⁻¹. Furthermore, the electrode exhibited an excellent energy density of 45.77Wh kg⁻¹ with a power density of 275W kg⁻¹, underscoring its superior energy storage performance. These results confirm the successful fabrication of highly efficient electrode material through a green, economical and facile method. The unique architecture and outstanding supercapacitor behavior of NiMn₂O₄/TiO₂-Chitosan composite make it a promising candidate for advanced energy storage applications.