Co‐pyrolysis of Lotus Pollen and Ammonium Nitrate to Produce Graphene‐Like Porous Carbon with Charge and Mass Transfer Highways for High‐Performance Supercapacitor

Abstract Biomass‐derived carbon‐based supercapacitors offer a promising sustainable energy storage strategy for addressing global energy and environmental challenges. Herein, we report the synthesis of a graphene‐like porous carbon by co‐pyrolysis of lotus pollen and ammonium nitrate. During the co‐pyrolysis process, ammonium nitrate could release a large amount of heat, etch the carbon skeleton, reduce the pyrolysis temperature, and create hierarchically porous carbon networks with rich N doping. The hierarchically N‐doped porous structure has an ultra‐large specific surface area (3106 m 2 g −1 ) and an adapted interconnected porous structure, provides highways for charge and mass transfer, leading to a specific capacitance as high as 373.7 F g −1 at 0.5 A g −1 current density. The symmetric solid‐state supercapacitor device exhibits a specific energy density of 53.5 Wh kg −1 at a power density of 640 W kg −1 .