Journal of Power Sources, Vol.176, No.1, 363-368, 2008
Nanostructured manganese oxide electrodes for lithium-ion storage in aqueous lithium sulfate electrolyte
Nanostructured manganese oxide electrodes are fabricated directly by electrochemical deposition. Surface morphology of the electrode deposited at high-current density shows nanowires with diameter 12-16 nm distributed randomly. Nanowires tend to aggregate to clumps when the deposition current density is low. Both annealing temperature and deposition current density affect the electrochemical performance of the deposited manganese oxide electrode in an aqueous lithium sulfate electrolyte. An optimal annealing temperature is found to be 300 degrees C in terms of the electrode's specific capacity during high-rate charging/discharging. An electrode with thinner nanowires deposited at high-current density has a high-specific capacity because thinner nanowires shorten the diffusion of lithium ions and in favor of high-rate charging/discharging. (C) 2007 Elsevier B.V. All rights reserved.
Keywords:manganese oxide;lithium-ion storage;electrochemical capacitors;nanostructured materials;aqueous lithium-ion batteries