The effect of temperature and time of calcination on synthesis of YAG nano-crystalline by normal co-precipitation method

Nano-crystalline Yttrium aluminum garnet (YAG, Y3Al5O12) were synthesized by normal co-precipitation method using yttria and aluminum nitrates as the starting materials and ammonium hydrogen carbonate (AHC, NH4HCO3) as precipitant. To investigate the effect of temperature and holding time the resultant precursors were calcined at 900-1100 °C for 2 h also at 1100 °C for other durations (15, 30, 45 and 60 min). The evolution of phase composition and micro-structure of the as-synthesized YAG powders were characterized by different techniques such as X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, thermal analyses (TG/DTA), Specific surface area analyses (BET) and field emission electron microscopy (FESEM). The cubic YAG phase with an average grain size of 33 nm and specific surface area of 30 m2/g was completely formed at 1000 °C. In addition, pure YAG nano powders were obtained at 1100 °C in only 15 min calcination. Results showed that compared with increasing holding time, raising of temperature have more intense effect in increasing YAG crystal or particle size.