Radially Assembled V2O5 Microspheres with Exposed (001) Facets as High-Performance Cathodes for Lithium-Ion Batteries

Abstract

Vanadium pentoxide (V2O5) is a promising cathode material for lithium-ion batteries due to its high theoretical capacity and layered structure, yet its practical application is hindered by intrinsically low Li+ diffusivity. To address the limitation, we report a distinctive structural design of V2O5 microspheres assembled from radially aligned nanoribbons with predominantly exposed (001) facets. This architecture integrates microscale radial assembly and nanoscale crystallographic orientation, which synergistically shortens Li+ diffusion paths and provides rapid transport channels within the favorable (001) planes. The synthesis is achieved via a facile solvothermal-annealing route in which the morphology is tailored simply by varying the nitric acid concentration. Unlike previously reported V2O5 nanoribbon morphologies that are randomly stacked or film-like, our radial assembly fully exploits the anisotropic conduction of the (001) facets within a robust microsphere framework. When evaluated as a cathode, the nanoribbon-assembled microspheres deliver a high specific capacity of approximately 255 mA h g–1 at 0.2 C and 140 mA h g–1 at 5 C, and retain 79% capacity after 100 cycles at 1 C. These values correspond to an 87% higher capacity at 5 C and a 12% greater capacity retention compared to randomly stacked nanoribbons. The superior lithium storage performance is attributed to the synergistic effects of the hierarchical radially aligned mesoporous architecture, the preferential (001) facet exposure, and the mechanical integrity of the microspheres, highlighting a novel design strategy distinct from existing V2O5 cathode morphologies.