Oxygen enriched carbon with hierarchical porous structure derived from biomass waste for high-performance symmetric supercapacitor with decent specific capacity

In this account, elm seeds are employed to prepare oxygen enriched porous carbon materials with three-dimensional honeycomb-like structure (HLPC). The HLPC demonstrates favorable specific capacitance of 501 F/g at 1 A/g. Moreover, the assembled HLPC//HLPC symmetrical device delivers 18.6 Wh/kg at 1310 W/kg and maintains 8.36 Wh/kg at 13090 W/kg, which is regarded as competitive electrode compared with the previously reported biomass carbon-based materials. The outstanding performance is attributed to exceptional oxygen content, which could significantly enhance the overall capacitance and improve the wettability of the electrode. This work holds great potential to realize high-efficient, eco-friendly and industrial-grade production of biomass-derived carbon materials for advanced energy storage applications.