Synthesis and electrochemistry of a vanadium-pillared manganese oxide

A new manganese dioxide pillared by vanadium oxide species has been synthes ized hydrothermally from permanganate. It has the electrochemically active MnO2 layer structure, which has been extensively studied as a battery catho de. The vanadium oxide ions, together with the water molecules, reside in b etween the oxide sheets; dehydration occurs without structural change. The (VOy)(0.1)MnO2. nH(2)O has a rhombohedral structure, with hexagonal paramet ers a = 2.843(6) Angstrom, c = 22.08(2) Angstrom. It reacts readily with li thium with a capacity around 150 mAh g(-1); the pillar ions do not appear t o impede reaction. (C) 2000 Elsevier Science S.A. All rights reserved.