Superb sono-adsorption and energy storage potential of multifunctional Ag-Biochar composite

Silver embedded banana peel biochar (Ag-BBc) composite was tailored effectively by green synthetic route. Azadirachta indica leaf extract was employed for preparation of Ag nanoparticles as reducing agent and biochar was derived from the of banana peel via pyrolysis. The multi-functionality of the fabricated nanocomposite was investigated through its application towards energy storage and environmental remediation. The prepared composite was characterized in detail by various analytical techniques and the electro-chemical aspects were examined by cyclic-voltammetry and galvanostatic charge-discharge methods. The improved specific capacitance of Ag-BBc composite was measured as 655 Fg^-1 in 1 M Na₂SO₄ at a current density of 0.35 Ag^-1. The Ag-BBc modified electrode exhibited an excellent cyclic stability of 79.3% after 5000 charge/discharge cycles and displayed high energy and power density of 40 Wh/kg and 490 Wkg⁻¹ respectively, at 1 Ag^-1. Furthermore, Ag-BBc composite was used for the ultrasonic assisted adsorption of Congo Red dye with appreciable adsorption efficacy of ∼98% within 5 min of contact time. Langmuir and Freundlich isotherms were considered to describe the equilibrium of dye using ultrasonic assisted adsorption process.