Graphene modified Sb2O3/porous carbon nanofibers via electrospinning treated in air for potassium-ion batteries with enhanced cycling stability

Abstract

Sb2O3 is regarded as an ideal anode material for potassium-ion batteries for its high theoretical specific capacity. However, the potassiation and depotassiation during cycling causes large volume change which will result in cracking of the electrode and irreversible loss of capacity. Here, we prepared graphene-modified Sb2O3 porous carbon nanofiber by electrospinning and subsequent annealing in air as anode material of potassium-ion batteries. The mechanical properties of the electrode materials are greatly enhanced owing to the introduction of graphene with the Young's modulus increased to 3045.5 MPa from 1367.9 MPa. Ultimately, the as-prepared Sb2O3@GPCN-100 porous fibers delivered a high specific capacity of 327 mAh g−1 after 300 cycles at a current density of 500 mA g−1. Even at a high current density of 1000 mA g−1, the electrode exhibits a specific capacity of 292 mAh g−1 after 600 cycles, showing excellent reversible stability and high specific capacity. This graphene modification strategy can also provide a feasible solution for the modification of other anode materials for potassium-ion batteries.