Aqueous-Based Chemical Route toward Ambient Preparation of Multicomponent Core–Shell Nanotubes

Abstract

Room-temperature synthesized V₂O₅@MnO₂ core–shell nanotubes with tunable tunnel dimensions <i>via</i> 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