Nitrogen and Oxygen Dual-doped Porous Carbon from Nature Macromolecular Chitosan for Fast and Stable Zinc-ion Hybrid Supercapacitors

Abstract Zinc ion hybrid capacitors (ZIHCs) with carbon-based material cathodes have shown considerable potential in many energy-related applications since they have the advantages of supercapacitors and batteries. However, these carbon-based materials still suffer from the limitations of low energy density and poor cycle stability as cathodes in ZIHCs because of their low surface areas and unsatisfied chemical structures. Herein, nitrogen and oxygen dual-doped porous carbon materials were prepared in situ by using the precursors of nature macromolecular chitosan with abundant amino and hydroxyl groups. Due to the developed mesopores, solid structures, and fast redox response from the dual-doped N and O heteroatoms, the prepared ZIHCs based on these novel carbon materials show high specific capacity of 100 mAh g-1, outstanding energy density of 172.24 Wh kg-1 and good stability over 20,000 cycles at large charging/discharging current density of 5 A g-1. These findings will contribute greatly to the development of environmentally friendly Zn-based energy devices.