OPTIMIZING PARAMETERS IN SYNTHESIS OF LiF NANOPOWDERS VIA SOL–GEL METHOD

Abstract

Lithium fluoride (LiF) nanopowders were prepared by trifluoroacetate-based sol–gel processing. In this work, lithium acetate dehydrate ( LiAc ⋅ 2H2O ) and trifluoroacetic acid (TFA) was used as lithium and fluorine sources. The thermal behavior of initial gel was examined using differential thermal analysis (DTA). Effects of solvent (glacial acetic acid, absolute ethanol, and ethylene glycol), Li+ concentration (0.5, 1, and 2 mol/l) and decomposition temperature (200, 250, and 300°C) on synthesis of LiF nanopowders by sol–gel method were investigated. The results of LPSA, FE-SEM, and XRD showed that the growth of particles and aggregation can be controlled by changing above parameters. However, it is indicated that optimum conditions are; solvent as ethanol, Li ion concentration (0.5 mol/l), and decomposition temperature (300°C), respectively. Also, the addition of oleic acid as an organic additive made the final LiF particles finer and about 70–90 nm.