Analytical electron microscopy studies of lithium aluminum hydrides with Ti- and V-based additives

The microstructure of LiAID(4) with TiCl(3)center dot 1/3(AlCl3) and VCl3 additives has been studied during different steps of the decomposition process using electron energy loss spectroscopy and energy-dispersive X-ray spectroscopy in a scanning transmission electron microscope. Energy filtered transmission electron microscopy was used to show elemental distributions in the samples. The spatial distribution of the additives and the main elements within the alanate particles was examined with a resolution of a few nanometers. The analysis of the electron energy loss spectra reveals the chemical state of Al, O, and the additives. Ti and V do not appear to mix chemically with Al to a significant degree. V was found in high concentration in just a few particles, while Ti is more uniformly distributed. All the samples showed evidence of oxidation despite procedures being adopted to avoid exposing the material to air. The additives are oxidized in all the samples, and Al2O3 forms a thin layer at the surface of the particles. This paper gives a comparison between samples at different stages of the decomposition process using different additives.