The g-C3N4-derived nanoarchitectonics of nitrogen-doped carbon material as a high-rate performance anode for potassium ion batteries

Due to the advantages of abundant precursors, simple preparation, and environmental friendliness, nitrogen-doped carbon is considered one of the most potential anodes for potassium ion batteries (PIBs). Here, nitrogen-doped carbon materials (NC-2) were prepared by using secondary exfoliated g-C3N4 as a precursor, combined with sucrose, and subjected to hydrothermal and high-temperature pyrolysis. NC-2 is characterized by high nitrogen content, porous layered structure, and large interlayer spacing. NC-2 used as anode of PIBs shows a high reversible capacity of 261.07 mAh g-1 at 0.1 A g-1 and an impressive rate performance of 153.36 mAh g-1 at 2 A g-1. The impressive performance of NC-2 can be originated from the porous layered structure and enlarged interlayer spacing promotes the intercalation/deintercalation and the diffusion of K ions, and the defective carbon structure formed after nitrogen doping can supply abundant active sites for K ions. The results show that NC-2 has great potential in the field of PIBs anode.