posted on 2005-05-04, 00:00authored byErin M. Sorensen, Heather K. Izumi, John T. Vaughey, Charlotte L. Stern, Kenneth R. Poeppelmeier
Low-temperature hydrothermal techniques were used to synthesize single crystals of Ag4V2O6F2.
This previously unreported oxide fluoride phase was characterized by single-crystal X-ray diffraction and
IR spectroscopy and was also evaluated as a primary lithium battery cathode. Crystal data: monoclinic,
space group P21/n (No. 14), with a = 8.4034(4) Å, b = 10.548(1) Å, c = 12.459(1) Å, β = 90.314(2)°, and
Z = 4. Ag4V2O6F2 (SVOF) exhibits two characteristic regions within the discharge curve, an upper plateau
at 3.5 V, and a lower sloped region around 2.3 V from reduction of the vanadium oxide fluoride framework.
The material has a nominal capacity of 251 mAh/g, with 148 mAh/g above 3 V. The upper discharge plateau
at 3.5 V is nearly 300 mV over the silver reduction potential of the commercial primary battery material,
Ag2V4O11 (SVO).