Synthesis and electrochemistry of a vanadium-pillared manganese oxide

A new manganese dioxide pillared by vanadium oxide species has been synthesized hydrothermally from permanganate. It has the electrochemically active MnO2 layer structure, which has been extensively studied as a battery cathode. The vanadium oxide ions, together with the water molecules, reside in between the oxide sheets; dehydration occurs without structural change. The (VOy)0.1MnO2·nH2O has a rhombohedral structure, with hexagonal parameters a=2.843(6) ?, c=22.08(2) ?. It reacts readily with lithium with a capacity around 150 mAh g-1; the pillar ions do not appear to impede reaction.