Synthesis of natural oxygen-doped bamboo-derived hierarchical micro-mesoporous composite carbon materials using a green activation strategy

Utilizing biomass waste to synthesize hierarchical micro-mesoporous composite carbon materials for application in the field of supercapacitors realized green and sustainable energy development. This paper efficiently synthesized natural O-doped carbon materials using bamboo as biomass material by simple air pre-oxidation and secondary carbonization methods. Among them, KCl acted as a recyclable templating agent and flame retardant, facilitating the construction of mesoporous structures. The green activator CH3COOK promoted the generation of micropores. The combination of dual activation strategies (physical and chemical) contributed to the conversion of bamboo to hierarchical micro-mesoporous composite carbon materials. During pre-carbonization, air was used as a natural dopant which etched the carbon material and promoted the creation of oxygenated functional groups. The best carbon material exhibited an excellent electrochemical capacity of 321.65 F/g in 6 M KOH electrolyte. Furthermore, the symmetric supercapacitor exhibited high cycling stability (95.52 %) and outstanding power density. This work provided a new idea for preparing controllable biomass-derived carbon materials, while offering a reference for applying dual activation strategies in carbon material synthesis.