Research advances in plant-derived activated carbon for electric double layer capacitors

Electric double-layer capacitors (EDLCs) are high-power, long-cycle energy storage device with a wide operational temperature range, making them a promising technology for transportation, micro-grids, and the Internet of Things. The activated carbon, serving as a key material for EDLCs, exhibits exceptional attributes including an elevated surface area, substantial tap density, and abundant nanoporosity. Plants have long been regarded as the most promising precursors for produce activated carbon, owing to their abundant availability, diverse range of species, and renewable nature. This study provides a review on plant-derived activated carbons for electric double-layer capacitors (EDLCs). The initial section of this mini review briefly elucidates the advantages and operational mechanism of EDLCs. Subsequently, plant-derived precursors for activated carbon are categorized into four distinct groups: agricultural and forestry residues, aquatic biomass, fruit shells, and plant-based molecules. The subsequent section of the review discusses the prerequisites for activated carbon production, along with the mechanisms and methodologies employed in its preparation. Furthermore, this study reviews recent advancements in utilizing plant materials as precursors for activated carbon production and explores catalytic graphitization techniques to enhance their electrochemical performance in EDLCs. Finally, the concluding remarks are presented in the fourth section, outlining prospects for potential applications in EDLCs and future research directions for plant-derived active carbon.