Synthesis and electrochemical performance of bismuth–vanadium oxyfluoride

Bismuth–vanadium oxyfluoride (Bi2VO5F) has been synthesized using a simple, solid-state reaction process at different sintering temperatures. The structure and performance of the samples have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge/discharge experiments. The results show that bismuth–vanadium oxyfluoride belongs to a tetragonal crystal system with space group I4mm. The sample that was synthesized at 550 °C (P550) exhibits relatively good electrochemical properties. Sample P550 shows a high, initial discharge capacity of 222 mAh g−1 at a rate of 100 mA g−1 between 1.4 and 3.5 V. Sample P550 also shows acceptable electrochemical cycling properties. After the first cycle, the discharge specific capacity remains between 106 and 155 mAh g−1, which plateaus between 2.1 and 1.9 V during the first 15 cycles.

► Bi2VO5F has been prepared by solid-state method.
► The electrochemical behaviors of Bi2VO5F have been studied.
► Bi2VO5F prepared at 550 °C shows good electrochemical performances.