Boron-doped biomass-derived nanocarbon for efficient supercapacitors: bridging waste recycling and energy storage

Abstract

This study comprehensively evaluates boron doping in biomass-derived carbon for its applications in supercapacitors. To synthesize the B-NC nanocomposite, a two-step approach was employed. Biomass-derived activated carbon was first annealed at 1200 °C to enhance its structural properties. Boron was then introduced into the carbon matrix through a hydrothermal doping process. The incorporation of boron induces a p-type defect and thus enhances the overall conductivity of the nanocomposite. Morphological and structural analysis was conducted using various characterization techniques, including FE-SEM, HR-TEM, XRD, Raman, XPS, and BET studies, to investigate the overall architecture of the B-NC nanocomposite. The electrochemical performance was studied in three-electrode and two-electrode setups for supercapacitor applications. CV, GCD, and EIS techniques are used to study the supercapacitor behavior of B-NC. The highest specific capacitance obtained by the nanocomposite is 539.5 F g⁻¹, while the highest energy density, power density, and coulombic efficiency calculated were 40.5 Wh kg⁻¹, 7500 W kg⁻¹, and 104.4%, respectively. Additionally, the highest specific capacitance of the device was 129.87 F g⁻¹. The nanocomposite shows high cycling stability up to 5000 cycles at a current density of 10 A g⁻¹. This study shifts the attention of researchers toward exploring sustainable, cost-effective, and facile techniques for fabricating energy storage devices.