A facile biotemplate-assisted synthesis of mesoporous V2O5 microtubules for high performance asymmetric supercapacitors

Mesoporous V2O5 microtubules are synthesized using a biotemplate-assisted method and evaluated for using as supercapacitor electrode materials. The preparation process is facilely associated with the pyrolysis of cotton fiber, adsorbed with the vanadium pentoxide hydrates. The obtained microtubular V2O5 shows highly mesoporous merits and hollow interiors, leading to better electrolyte/electrode contact and more efficient transport pathways. Compared with bulk V2O5 prepared without using cotton as biotemplate, microtubular V2O5 displays the excellent electrochemical performance with a specific capacitance of 680 F g(-1) at 1.0 A g(-1) in 1 M LiNO3 aqueous electrolyte and a high capacity retention of 70% over 10,000 cycles at 3 A g(-1) in LiClO4/ propylene carbonate organic electrolyte. Moreover, the asymmetric supercapacitors based on microtubular V2O5 exhibit a high energy density of 58 Wh kg(-1) at a power density of 0.46 kW kg(-1) in 1 M LiClO4/propylene carbonate organic electrolyte, which further indicates that the great potential of the microtubular V2O5 as high-performance energy storage devices.