Synthesis of MnV₂O₆ under autogenous hydrothermal conditions and its anodic performance

Anhydrous crystalline powders of MnV₂O₆ (brannerite) were successfully precipitated from mixed aqueous solution of Mn(CH₃COO)₂ and V₂O₅ with a metal ion concentration of 0.01-1.0 mol/l at 135-200 °C under autogenous hydrothermal condition in a closed vessel. The characterization of MnV₂O₆ synthesized was carried out by XRD, TG, TEM and anodic performance measurement. In case of mixtures with a concentration of 0.1-1.0 mol/l, single phase anhydrous crystalline MnV₂O₆ with homogeneous thin rod-like particles were synthesized by autogenous hydrothermal process, though starting reagent V₂O₅ was not fully dissolved. They showed high anodic performance in lithium ion batteries; high charge capacity as 600 mA h/g even after the 10th cycle and stable cyclic performance. MnV₂O₆ powders synthesized from relatively high concentration of metal ions showed an abrupt increase in charge capacity after third or fourth discharge/charge cycles, though the first cycle showed rather high irreversible capacity.