Recent advancements in biomass-origin carbon structures for next-generation supercapacitors

The urgent global need for efficient, clean, and sustainable energy storage technologies has underscored the importance of supercapacitors as vital components in future energy systems. Their high power density, excellent cycle life, and rapid charge-discharge capabilities make them particularly attractive for diverse sustainable applications. Among emerging materials, biomass-derived carbon has gained significant attention due to its renewability, hierarchical porosity, and tunable surface chemistry, especially when enhanced through heteroatom modification. These distinctive features improve electrochemical performance, positioning biocarbons as promising candidates for next-generation supercapacitor electrodes. This review highlights recent advances (2020-2025) in biocarbon-based supercapacitors, focusing on how structural engineering, porous architectures, and chemical doping influence charge retention, energy density, and conductivity. Beyond performance metrics, it emphasizes the environmental and circular-economy benefits of recycling biowastes for sustainable energy solutions. The paper concludes with reflections on current challenges, practical considerations for scaling, and future research directions to advance biomass-derived carbon electrodes.