PVP-assisted synthesis of g-C3N4-derived N-doped graphene with tunable interplanar spacing as high-performance lithium/sodium ions battery anodes

Carbon materials have attracted abundant attentions and been utilized widely as anodes in rechargeable Lithorn /Nathorn /Kthorn ions batteries. Regarding the various radius of alkali-metal-ions, reversible intercalation and deintercalation in interlayers of carbons requires different interplanar spacing. In this work, N-doped graphene with tunable interplanar spacing is synthesized using graphitic carbon nitride (g-C3N4) as precursor with the assistance of polyvinylpyrrolidone (PVP). The obtained tunable interplanar spacing in the range from 0.34 nm to 0.45 nm with enlarged values is mainly ascribed to the high nitrogen doping levels (9.98-33.7 at. %), especially to the pyrrolic nitrogen. Serving as the anode materials in lithium ions batteries (LIBs) and sodium ions batteries (SIBs), promising specific capacities of 1236 mAh g(-1) for LIBs and 300 mAh g(-1) for SIBs at current density of 0.05 A g(-1) and excellent cycling stability as well as acceptable rate capability are demonstrated for the resultant N-doped graphene. The influences of interplanar spacing on the electrochemical performances of LIBs and SIBs are investigated comparatively. This work outlines a facial route to synthesize N-doped graphene with tunable interplanar spacing, meeting the various requirements unitized as anodes in rechargeable Lithorn/Nathorn/Kthorn ions batteries. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

This study demonstrates the synthesis of N-doped graphene with tunable interplanar spacing, showing promising performance as an anode material in lithium ions batteries and sodium ions batteries, with excellent specific capacities, cycling stability, and rate capability.