Mesopore-dominant defective nitrogen-doped tubular porous carbon for electrochemical energy storage

Biomass-derived carbon materials have grasped tremendous interests owing to the abundance, affordability, environmental friendliness, and potential for efficient energy storage. Herein, mesopore-dominant nitrogen-doped tubular porous carbon (NTPC) possessing abundant defects from cattails was rational synthesized through one-step activation and doping approach. The profound roles of pore structure and N heteroatoms were explored by physical characterization and electrochemical tests. Importantly, the dominated mesopores accelerate free access of electrolytes to the interior and build rapid ions transfer channels, while the incorporation of nitrogen heteroatoms modifications gives to more active sites for ions storage via arising of surface defects. The NTPC materials exhibit excellent energy storage and rate capabilities in lithium-ion batteries and supercapacitors applications. Serving as the anode of lithium-ion batteries, the reversible specific capacity 810 mAh g−1 could be achieved at 100 mA g−1, and the capacity retention rate remains 97.4 % after 500 cycles at 500 mA g−1. Meanwhile, NTPC delivered an impressive specific capacitance of 271 F g−1 at 1 A g−1 as electrode material in electrochemical supercapacitors, where only 0.5 % loss of capacitance in a symmetric supercapacitor was obtained even after 10,000 cycles at 10 A g−1, indicating the remarkable cycling durability and promising potential in electrochemical energy storage.