Syntheses and Characterization of Gd₃Al₅O₁₂ and La₃Al₅O₁₂ Garnets.

Abstract

Aluminum I 2100Syntheses and Characterization of Gd3Al5O12 and La3Al5O12 Garnets. -The title compounds are synthesized by aqueous sol-gel processes using Gd 2 O 3 , La 2 O 3 , Al(NO3)3, HOAc, and glycol as starting materials. The obtained powders are sintered in air at different temperatures for 10 h and characterized by powder XRD, IR spectroscopy, and SEM. Monophasic Gd3Al5O12 samples are obtained at lower sintering temperatures (900-1100°C) compared with the temperature required for the solid state synthesis (>1600°C). The heat treatment of La-Al-O precursor gel powders at the same temperature leads to the formation of 3LaAlO3:Al2O3 or LaAlO3:La2O3:2Al2O3 mixtures instead of the single La3Al5O12 garnet phase. The proposed aqueous sol-gel method is inexpensive and thus appropriate for the large-scale production of new ceramic materials. -(GARSKAITE, E.; DUBNIKOVA, N.; KATELNIKOVAS, A.; PINKAS, J.; KAREIVA*, A.; Collect. Czech. Chem. Commun. 72 (2007) 3, 321-333;

Aqueous Sol-Gel Synthesis Methods for the Preparation of Garnet Crystal Structure Compounds

“…According to XRD analysis fully crystallized single-phase oxides Lu 3 Ga 5 O 12 with well pronounced garnet crystal structure have formed. [38,41,43,44]. Thus, rare earth aluminium garnets are thermodynamically stable with RE = Gd -Lu.…”