Unleashing supercapacitor potential via carbon nano onions infused with nickel oxide microspheres and hydrogel electrolyte

Abstract The research focuses on developing advanced electrode and electrolyte materials for high-performance biodegradable supercapacitors. This goal is accomplished through the synthesis of porous nickel oxide (NiO) hollow microspheres incorporated with carbon nano-onions (CNO), serving as the electrode material. The electrolyte chosen for this study is a composite of sodium alginate (SA) and viologen. Comprehensive physicochemical analyses like XRD, BET, SEM, TEM, and various electrochemical analyses were conducted to evaluate the characteristics and properties of the synthesized electrode material. Viologen enhanced the properties of the supercapacitor with a specific capacitance of 638 F/g at the current density of 1 mA/cm 2 . The remarkable electrochemical performance demonstrated by the newly created electrode within a hydrogel electrolyte establishes its potential for deployment in next-generation high-performance supercapacitor applications.