In situ soft-chemistry synthesis of β-Na0.33V2O5 nanorods as high-performance cathode for lithium-ion batteries†
Abstract
β-Na0.33V2O5 nanorods were prepared via a facile soft-chemistry strategy using Na+ intercalated (NH4)0.5V2O5 nanosheets as precursor. Based on X-ray diffraction, Fourier transform infrared spectra and scanning electron microscope analysis, the formation mechanism of β-Na0.33V2O5 nanorods is proposed, which involves cation co-intercalation and crystal structure slip as well as a phase transformation process induced by cation release. When used as cathode for lithium-ion batteries, β-Na0.33V2O5 nanorods calcined at 600 °C exhibited good stable cycling behaviour with high capacity retention of 81.3% after 50 cycles. Reversible discharge capacities of 237.8, 199.8, 183.5, 151.7 mA h g−1 and 110.5 mA h g−1 can be delivered at 30, 60, 150, 300 and 600 mA g−1, respectively. It is expected that the Na0.33V2O5 nanorods could be employed as a promising cathode material in rechargeable lithium-ion batteries.