Facile and controllable construction of vanadium pentoxide@conducting polymer core/shell nanostructures and their thickness-dependent synergistic energy storage properties

Thickness- and morphology-controlled vanadium pentoxide/polyaniline (V₂O₅/PANI) core/shell hybrid nanofibers are fabricated by electropolymerization of PANI on V₂O₅ nanofibers for enhanced energy storage. By simply adjusting the electrodeposition time, the thickness of the PANI shells can be controlled from 5 nm to 47 nm, and the morphology can be changed from coaxial to branched. The influence of shell thickness on the improved Li-ion storage performance of the V₂O₅/PANI core/shell nanofibers is systematically investigated, and this enhancement of charge capability and cycling stability strongly varies with the shell thickness. Thickness-dependent synergistic electron transport, Li-ion diffusion distances, and shell mechanical strength mechanisms are also proposed. These results provide meaningful references for developing new functional core/shell materials and high-performance energy storage composite materials.