Facile synthesis of V2O5/graphene composites as advanced electrode materials in supercapacitors

Hybrid electrode materials are key for electrochemical performances of supercapacitors. In this work, vanadium pentoxide (V2O5) is grown on graphene by a microwave synthetic method, which is simple, rapid, energy-saving and efficient. Benefiting from the microwave synthetic method, uniform V2O5 nanoparticles with an approximately size of 20 nm are evenly dispersed on graphene. The resultant V2O5/graphene composites are assembled into symmetrical supercapacitors, exhibiting specific capacitances of 673.2 and 474.6 F g(-1) at 1 and 10 A g(-1), respectively, and 96.8% of capacitance retention after 10,000 cycles at 1 A g(-1). Additionally, the assembled devices show outstanding energy density and power density characteristics (46.8 Wh kg(-1) at 499.4 W kg(-1) and 32.9 Wh kg(-1) at 4746.0 W kg(-1)), which are superior than many similar devices. Furthermore, capacitive performances of V2O5/graphene composites with five different component ratios are thoroughly investigated and the charge storage mechanism is discussed. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

Hybrid electrode materials of vanadium pentoxide (V2O5) grown on graphene by a microwave synthetic method exhibit excellent electrochemical performances in supercapacitors, with specific capacitances, capacitance retention, energy density, and power density surpassing many similar devices. This study also investigates the capacitive performances of V2O5/graphene composites with different component ratios and discusses the charge storage mechanism comprehensively.