Naturally nitrogen-doped porous carbon derived from waste crab shell as anode material for high performance sodium-ion battery

Transformation of biomass wastes into sustainable low-cost carbon materials is now a topic of great interest. Here, a novel porous carbon has been prepared through activation of crab shell, which demonstrates an interconnected hierarchical porosity comprised of macro-, meso- and micro-pores as well with a high specific surface area of 1153.6 m2 g−1. Benefiting from the unique pore structure and oxygen and nitrogen dual doping, a well-developed ionic and electronic conductivity is achieved. Remarkably, when used as a anode material for sodium-ion batteries, it exhibits good cycling stability with a capacity up to 339.1 mA h g−1 at a current density of 0.03 A g−1, and maintains a capacity of 132.4 mA h g−1 even at a high current density of 0.5 A g−1 after 200 cycles, and still maintain high Coulomb efficiency. These results indicate that the fabricated porous carbon could be a promising electrode material for sodium-ion batteries.