Combustion synthesis of γ-lithium aluminate by using various fuels

Combustion synthesis, which is a quick and straightforward preparation process to produce homogeneous, crystalline and unagglomerated multicomponent oxide ceramic powders without the intermediate decomposition and/or calcining steps, was used to prepare γ-lithium aluminate. Lithium nitrate and aluminium nitrate were used as the starting materials and various organic compounds, such as citric acid, urea, carbohydrazide, glycine and alanine, as the fuels. The mixture of nitrate and fuel could be ignited at 450 °C, but only urea and carbohydrazide could be reacted with the mixed nitrates to result in dry, loose and white γ-LiAlO2 powders. In this study, the effects of fuel type and ratio of fuel to nitrates on the phase formation of γ-LiAlO2 powder were investigated and also discussed. Additionally, the phase and morphology of the γ-LiAlO2 powder synthesized by the combustion reaction were compared with that by the conventional solid state reaction.