International Journal of Energy Research, Vol.44, No.4, 3215-3223, 2020
Facile preparation of NaV3O8/polytriphenylamine composites as cathode materials towards high-performance sodium storage
NaV3O8/polytriphenylamine composites were synthesized by an in situ oxypolymerization way for the first time. Among them, the NaV3O8/20 wt.% polytriphenylamine composite shows better cycling and rate performance. Its discharge capacity retains at 118.9 mAh g(-1) after 300 cycles at 120 mA g(-1). It also obtains a reversible capacity of 101.7 mAh g(-1) at 300 mA g(-1) after 100 cycles. These enhanced results arise from the excellent morphology, that is, smaller particles of clear edges and uniform distribution suppress the expansion and deformation of the crystal structure, and avoid large agglomerate particles gathering during the electrochemical reaction. In addition, tight polytriphenylamine (PTPAn) coating also improves the conductivity of NaV3O8 cathode and suppresses the dissolution of NaV3O8 in electrolyte.
Keywords:cathode materials;in situ oxypolymerization method;NaV3O8;polytriphenylamine composite;sodium-ion batteries