Aqueous-based chemical route toward ambient preparation of multicomponent core-shell nanotubes

Room-temperature synthesized V2O5@MnO2 core-shell nanotubes with tunable tunnel dimensions via a facile aqueous-based method are presented. The rational-designed tubular morphology endows them with good permeability of electrolyte ions for maximum utilization of the electroactive sites, while the epitaxial-grown MnO2 imposes mechanical support to V2O5 against structural collapse upon long-term cycling. Hence, specific capacitance as high as 694 F g(-1) is achieved at 1 A g(-1) accompanied by excellent cycling stability (preserved 92% of its initial specific capacitance after 5000 cycles). In addition, functionalization of the V2O5@MnO2 nanotubes with other transition metal oxides results in ternary composites, V2O5@MnO2/M nanotubes (M = Fe2O3, Co2O3/Co(OH)2, Ni(OH)2). The versatility of this synthetic protocol provides a platform to fabricate complex ternary nanocomposites in a more benign way.