Rapid preparation of porous carbon by flame burning carbonization method for supercapacitor

Herein, the feasibility of simple and quick to fabricate porous biocarbon materials by a universal flame burning carbonization synthetic strategy is investigated. Cotton, dandelion and catkin are fluffy that contain lots of air between the tissues, which are low ignition point and flammable substances, they are easily lighted and carbonized. K2CO3-KCl not only play the role of activator and template agent, but also cover the surface of substance in the form of molten state to isolate air with biocarbon and prevent the burn out of biomass. The prepared carbon has hierarchical porous structure, large specific surface area and abundant heteroatoms doping, and can reach a high specific capacitance of 367 F g−1 in 6 M KOH. In addition, we also prepare a large voltage window of K2CO3-glycol-arginine electrolyte, and the assembled symmetric supercapacitor with the prepared electrolyte and porous carbon exhibits an energy density of 30.7 Wh kg−1 and a wide operating temperature from −25 to 100 °C. The practicable of flame burning rapid carbonization strategy, recycling K salt and large-scale production are verified. This study uncovers a new possibility for the rapid and commercial production of biomass based porous carbon materials for high performance supercapacitor.