Abstract
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 via 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.
