A renewable carbon material derived from native European deciduous trees serves as a sustainable electroactive substance for multifunctional energy storage systems

Carbon derived from biomass, characterized by its abundant porosity and adaptable physical and chemical traits, has emerged as a promising choice for electrode materials in electrochemical energy storage devices like supercapacitors and lithium-sulfur (Li-S) batteries, marking a rapidly advancing field. Herein, we report the creation of a fresh biomass-derived activated carbon produced <i>via</i> a pyrolysis technique using a blend of indigenous European deciduous trees, including Birch, Fagaceae, and Carpinus betulus (commonly referred to as European hornbeam). The biomass-derived activated carbon underwent various material characterizations to scrutinize its structural, morphological, and elemental compositions. Utilizing this biomass-derived activated carbon as the electrode material across different supercapacitor configurations (such as coin cells and printable miniaturized devices) and as sulfur hosts in Li-S batteries paves the way for expanded applications in biomass energy utilization. The supercapacitor devices were successfully fabricated and shown to be operated efficiently within an operational potential range of 2.5 V (0.0-2.5 V) utilizing an EMIMBF₄ ionic liquid electrolyte. The symmetrical coin cell supercapacitor device achieved a notable energy density of approximately 23.52 W h kg^-1 when subjected to an applied current density of 0.66 A g^-1. Furthermore, Li-S batteries were assembled, incorporating a composite cathode composed of activated carbon derived from biomass and sulfur. Subsequently, cyclic voltammetry alongside charge-discharge assessments at varying scan rates and C-rates were performed, respectively. The sulfur-biomass-derived activated carbon (BAC) composite delivers an initial discharge capacity of 661 mA h g^-1 at a C-rate of 0.05C. Long-term cycling tests were conducted at 1C and 0.5C over 500 cycles, achieving coulombic efficiencies of approximately 99% and 97%, respectively, in sulfur-biomass-derived activated carbon composite-based Li-S batteries. Hence, our research showcases the scalable synthesis of biomass-derived activated carbon and its utilization as a versatile electrode material, laying the groundwork for the next generation of multifunctional sustainable energy storage systems.