Versatile insertion capability of Na1.2V3O8 nanobelts in aqueous electrolyte solutions

•layered Na1.2V3O8 was synthesized by simplified soft chemistry method•fast insertion of Li, Na and Mg ions from aqueous solutions was evidenced•reproducible insertion reactions were observed even at highest scanning rates•promising behavior for aqueous recahrgeable metal-ion batteries was evidenced

Single phase nanobelt-like Na1.2V3O8 was synthesized by precipitation from aqueous solution of V2O5, H2O2 and NaOH, and subsequent annealing at 400 oC. The product was characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. As measured by both galvanostatic charging/discharging and cyclic voltammetry methods, in air-equilibrated aqueous electrolyte solutions containing nitrates of lithium, sodium and magnesium, this compound displayed fast intercalation/deintercalation reactions. The galvanostatic charging and discharging curves observed at rates ranging 500-7000 mA g-1, did not display clear plateaus characteristic of phase changes. The discharging capacities were found to range 101-35, 55-17 and 67-22 mAh g-1 for Li, Na and Mg intercalation, respectively. By cyclic voltammetry, for the sweep rates increasing in the range 5-400 mV s-1 (roughly 9-700 C), the capacity was found to decrease within the limits 63-35 mAh g-1 for Li+ intercalation, and 40 -11 mAh g-1 for Na+ and Mg2+ intercalation, respectively. By analyzing the dependence log (current) versus log (sweep rate), the interval of potentials corresponding to preferably diffusion control of intercalation/deintercalation processes was determined.

Graphical abstractXRD pattern, microphotography of nanocrystal particle shape, and cyclovoltammograms in aqueous Li, Na and Mg nitrate solutions of layered Na1.2V3O8.Figure optionsDownload full-size imageDownload as PowerPoint slide