Synthesis of Yttrium Aluminum Garnet from a Mixed-Metal Citrate Precursor

Yttrium aluminum garnet (YAG, Y3Al5O12) was synthesized using a polymeric precursor derived from a mixed-metal citric acid/ethylene glycol/ethanol solution. YAG was found to crystallize directly from an amorphous precursor beginning at temperatures as low as 600°C within 1 h in air. The polymer resin concentration was found to have an effect on the temperature of crystallization initiation. However, all precursors produced a well-crystallized YAG powder within 1 h at 800°C in air. Formation of phase-pure YAG in an argon atmosphere did not occur until heating for 1 h at 1000°C. An optimum cation-to-resin ratio to maximize reactivity provides a polymeric network to ensure a homogeneous dispersion of cations, yet minimizes cation diffusion distances within the char by limiting excess free carbon after polymer pyrolysis.

[1]  J. Halloran,et al.  Yttrium Aluminum Garnet Fibers from Metalloorganic Precursors , 2005 .

[2]  M. Cinibulk.  Effect of divalent cations on the synthesis of citrate-gel-derived lanthanum hexaluminate powders and films , 1999 .

[3]  M. Cinibulk.  Effect of Precursors and Dopants on the Synthesis and Grain Growth of Calcium Hexaluminate , 1998 .

[4]  J. Halloran,et al.  Synthesis of yttrium aluminum garnet from yttrium and aluminum isobutyrate precursors , 1996 .

[5]  J. Halloran,et al.  Polycrystalline Yttrium Aluminum Garnet Fibers from Colloidal Sols , 1995 .

[6]  M. A. Gülgün,et al.  Chemical Synthesis and Characterization of Calcium Aluminate Powders , 1994 .

[7]  R. Hay,et al.  Phase transformations and microstructure evolution in sol-gel derived yttrium-aluminum garnet films , 1993 .

[8]  H. Pickup,et al.  Synthesis of yttrium aluminum garnet by reverse strike precipitation , 1992 .

[9]  H. Takano,et al.  Formation of alkoxy-derived yttrium aluminium oxides , 1992 .

[10]  C. Veitch.  Synthesis of polycrystalline yttrium iron garnet and yttrium aluminium garnet from organic precursors , 1991 .

[11]  P. Lessing.  Mixed-cation oxide powders via polymeric precursors , 1989 .

[12]  H. Ling,et al.  Preparation of Y 3Al5 O 12 ‐ Based Phosphor Powders , 1987 .

[13]  G. Gowda.  Synthesis of yttrium aluminates by the sol-gel process , 1986 .

[14]  T. Takamori,et al.  Controlled nucleation for hydrothermal growth of yttrium-aluminum garnet powders , 1986 .

[15]  H. Anderson,et al.  Polymeric Precursor Synthesis of Ceramic Materials , 1986 .

[16]  H. V. Dijk,et al.  Translucent Y3Al5O12 ceramics , 1984 .