N-doped three-dimensional porous carbon materials derived from bagasse biomass as an anode material for K-ion batteries

To realize the sustainability of potassium-ion (K-ion) batteries for large-scale energy storage applications, a resource-abundant and cost-effective anode material is the key to design. Herein, we develop nitrogen-doped three-dimensional biomass porous activated carbon materials using bagasse biomass waste by carbonization and further activation with NiCl2 and urea as an advanced anode material for K-ion batteries. The results demonstrate that NiCl2 is an important factor in the formation of porous structure and nitrogen doping also promotes the change of morphology, enabling fast transport of K+ and electrons. More importantly, the as-synthesized carbon material could exhibit a superior K-storage property with a reversible capacity of 100.4 mAh g−1 at a current density of 200 mA g−1 over 400 cycles without any obvious capacity fading in K-ion batteries. This work provides significant guideline for structural design in large-scale application.