Submicro-sized LiMn 2 O 4 prepared by a sol-gel, spray-drying method

Abstract

Submicro-sized LiMn2O4 powders were produced by a sol–gel, spray-drying method in which a brown gel precursor was prepared via the reaction of LiOH alkaline solution with 1 M Mn(CH3COO)2. The gel precursor was then transferred into a dry precursor powder via a spray-dry process. After heating treatment the spinel LiMn2O4 powder was obtained. The composition and the crystal size of the samples were strongly affected by the spray speed in the drying process and the heating temperature. The structure and the morphology of LiMn2O4 powder were investigated by DTA, TGA, IR, XRD and SEM methods. It was discovered that submicro-sized LiMn2O4 powder could be formed under the conditions of rotating spray speed of 15 000 rpm and syntheses temperature of 700 � C. The electrochemical properties of LiMn2O4 samples in 1 M LiPF6, EC:DMC ¼ 1:1 solution were tested by measuring the voltammograms and charge–discharge curves. The submicro-sized LiMn2O4 sample made at 700 � C has a capacity of 128 mAh g )1 and good cycle stability for Li + intercalation reaction. This method may be applied