Thermal decomposition of Y3Al5O12 precursor synthesized by urea homogeneous co-precipitation

Yttrium aluminum garnet (YAG) nano-precursors were synthesized by urea homogeneous co-precipitation. The morphology and crystalline phase, particularly the in situ evolved gases of as-synthesized precursors during the thermal decomposition, were characterized and verified. The evolved NH 3 , H 2 O, and CO 2 gases can be observed below 600   °C. The released NO 2 gas was observed at 202   °C, 500   °C and 885   °C, which suggests that N O 3 − existed in the precursor with three different forms. Furthermore, the evolved SO 2 gas was detected above 850   °C due to desulfurization. Phase-pure YAG can be obtained when the precursor was calcined at 900   °C. The particle size increases with increasing calcination temperature. The powders calcined at 1100   °C were well dispersed and had an average grain size of 100   nm owing to the decomposition of S O 4 2 − at high temperatures.