Controlled synthesis of V2O5/MWCNT core/shell hybrid aerogels through a mixed growth and self-assembly methodology for supercapacitors with high capacitance and ultralong cycle life

Abstract

Vanadium pentoxide (V₂O₅)/multiwalled carbon nanotube (MWCNT) core/shell hybrid aerogels with different MWCNT contents are controlled synthesized through a facile mixed growth and self-assembly methodology. V₂O₅ coated MWCNTs from the in situ growth of V₂O₅ on the surface of acid-treated MWCNTs incorporate with V₂O₅ nanofibers from the preferred orientation growth of V₂O₅ in a one-step sol–gel process. These two kinds of one-dimensional fibers self-assemble into a three-dimensional monolithic porous hybrid aerogel. Owing to its high specific surface area, favorable electrical conductivity and unique three-dimensional and core/shell structures, the light weight hybrid aerogel (about 30 mg cm⁻³) exhibits excellent specific capacitance (625 F g⁻¹), high energy density (86.8 W h kg⁻¹) and outstanding cycle performance (>20 000 cycles). And the optimal content of MWCNTs in hybrid aerogels for the highest-performance supercapacitor is 7.6%.