Simultaneous Thermal Analysis of Lithium Aluminate SCS-Precursors Produced with Different Fuels

Lithium aluminate samples were obtained in reactions of solution combustion synthesis (SCS) with various types of fuel (glycine, leucine, and urea) from aluminum and lithium nitrate solutions. The simultaneous thermal analysis (STA) of precursors obtained in conditions of fuel and oxidizer stoichiometry showed the presence of impurities due to incomplete decomposition of initial salts containing carbon fragments of fuel and nitrate groups. An exception was the precursor from the dual-fuel SCS reaction, φ (glycine : urea) = 1 : 3, in which pure γ-LiAlO2 powder was formed. Replacement of lithium nitrate with lithium carbonate was found to reduce the process temperature and the relative amount of organic fuel. As a result, the content of carbon fragments in the precursor significantly decreased after synthesis.