Stringing metal–organic framework-derived hollow Co3S4 nanopolyhedra on V2O5 nanowires for high-performance supercapacitors

Abstract

Metal-organic framework (MOF)-derived metal sulfide-based nanostructures have been widely explored in electrochemical energy storage because of their high porosity and tunable morphology. However, the isolated particles are prone to aggregate and suffer from severe volume variation during electrochemical processes, resulting in compromised electrochemical properties. In this study, one-dimensional (1D) V2O5 nanowires are used as flexible backbone to string MOF-derived hollow Co3S4 three-dimensional (3D) nanopolyhedra to build robust core–shell 1D@3D V2O5@Co3S4 nanocomposites. The 1D V2O5 nanowires provide efficient electron transportation between Co3S4 nanopolyhedra. The hollow/porous structure of Co3S4 not only affords substantial electroactive sites, but also shortens the charge transport pathway.With these advantages, the optimal V2O5@Co3S4-5h displays enhanced electrochemical properties compared with control V2O5 or Co3S4-5h in three-electrode system. Furthermore, the asymmetric supercapacitor made from V2O5@Co3S4-5h exhibits high energy density (40.7 Wh/kg at 800 W/kg) with outstanding cycle durability, maintaining 85.9% incipient capacitance after 10,000 cycles. The present study opens up a new avenue for developing robust 1D@3D nanostructures for supercapacitors and electrocatalysis.