Pulsed Laser Deposition of Transition Metal Oxides for Secondary Batteries

Abstract

ABSTRACTPulsed laser deposition has been used to prepare thin films of several complex metal oxides of significance in secondary batteries from a single stoichiometric target with a substrate temperature of 600°C in the presence of 200 mtorr O2. Films of the candidate bifunctional air electrocatalysts, for metal air batteries, Lao.6Cao.4CoO3, Lao.6Sr0.4CoO3, Lao.6Cao.4MnO3 and Lao.6Sro.4MnO3 were prepared on glassy carbon substrates. Glassy carbon was found to either erode during the ablation process (with the cobaltates) or cause film cracking after deposition because of its extremely low coefficient of thermal expansion.. The use of stainless steel substrates yielded 0.3μm-thick dense films of Lao.6Cao.4CoO3 and Lao.6Cao.4MnO3 which were suitable for electrochemical measurements in concentrated alkaline electrolytes. LiMn2O4 and LiCoO2 films were prepared at thickness' of 0.3μm and 1 5μm The 0.3μm-thick films delivered 176 mC/cm2-μm and 323 mC/cm2-μm for LiMn2O4 and LiCoO2, respectively, in 1M LiClO4/PC.