Novel urea assisted polymeric citrate route for the synthesis of nanocrystalline spinel LiMn2O4 powders

Urea assisted polymeric citrate route was investigated for the synthesis of nanocrystalline spinel LiMn2O4 powders using metal nitrates/acetates, citric acid and urea under acidic condition at 300 °C. Optimum total metal ions to urea ratio was identified for the synthesis of organic free, phase pure nanocrystalline LiMn2O4 powders. Addition of urea changes the microstructure and combustion mechanism of polymeric intermediates as well as the structural coordination and phase formation of the LiMn2O4 powders, which are, respectively, confirmed through SEM, TG/DTA, FTIR and XRD analysis. Organic free phase pure nanocrystalline LiMn2O4 powder was synthesized by urea assisted polymeric citrate route with the total metal ions to urea ratio of 1:2 at 300 °C and the average crystallite size was found to be 19 nm.