Sol–Gel Combustion Synthesis of Nanocrystalline YAG Powder from Metal‐Organic Precursors

Abstract

Yttrium aluminum garnet (Y3Al5O12, YAG) nanocrystalline powders were synthesized by a novel sol–gel combustion process. Yttrium acetate and aluminum sec‐butoxide were used as the precursors and triethanolamine was used as the chelating agent and fuel. Thermal and crystallization behaviors of the YAG precursor powders were investigated by thermal gravimetric differential thermal analysis (DTA), Fourier transform infrared spectrum, and X‐ray diffraction. The combustion‐synthesized powders are amorphous and transform to a pure YAG crystalline phase at 900°C. The crystallization activation energy of amorphous YAG precursor was investigated by variable heating rate DTA. The calculated activation energy is 58.9 KJ/mol. The average crystalline size of heat‐treated YAG powders at 900°C is ∼20 nm.