Manganese Vanadium Oxide Nanotubes: Synthesis, Characterization, and Electrochemistry

Vanadium oxide nanotubes have been formed from the layered vanadium oxide precursor V 2 O 5+ δ [C 12 H 25 NH 3 ]. Both the precursor and tubes have been characterized. The black nanotubes have a relatively low thermal stability in oxygen, being oxidized to V 2 O 5 below 200 °C. A new manganese vanadium oxide nanotube, Mn 0.1 VO 2.5+ δ · n H 2 O, has been synthesized by ion exchange. These manganese tubes have a tetragonal layer with a = 6.157 (3) Å and an interlayer spacing c = 10.52 (3) Å. The nanotubes react with lithium chemically and are also electrochemically active in lithium cells. Two lithium atoms per vanadium can be incorporated chemically from n -butyllithium into both the manganese and the alkylammonium nanotubes. The manganese compound electrochemically intercalates 0.5 lithium per vanadium to a 2 V cutoff, giving a capacity of 140 A h/kg.