Constructing electron pathways by graphene oxide for V2O5 nanoparticles in ultrahigh-performance and fast charging aqueous zinc ion batteries

ABSTRACT Vanadium pentoxide (V2O5) materials show great promise in rechargeable aqueous zinc ion batteries (ZIBs) from its outstanding theoretical capacity. Limited to the poor electronic conductivity and sluggish ionic diffusion kinetics, most of the V2O5-based cathodes exhibit unsatisfactory specific capacity and short lifespan. Herein, V2O5/graphene oxide composite (V2O5/GO)，which V2O5 nanoparticles in-situ grow on GO plates, are facile synthesized as cathodes for ZIBs. The V2O5/GO heterojunctions have a continuous electron transfer pathways and abundant Zn2+ insertion active sites, a capacitive-controlled kinetics, and an improved hydrophilicity. As a result, this V2O5/GO-ZIBs display an admirable capacity of 525 mAh g-1 at 0.1 A g-1, remarkable rate capability of 114 mAh g-1 at 40 A g-1, long lifespan up to 10000 cycles at 20 A g-1 with 90.8% retention, extreme-fast charging ability of 12.8 s at 40 A g-1, greatly outperform most of reported ZIBs. Therefore, this work may guide the commercial application of ZIBs based on the superior performance and the simple synthesis approach.