柠檬酸-凝胶燃烧法制备钇铝石榴石(Y_3Al_5O_(12))纳米粉体的研究

透明YAG多晶陶瓷具有优良的光学、力学与化学性能,逐渐成为新一代固体激光基质材料。分散均匀、团聚轻的纳米粉体有利于制备出高度透明的激光陶瓷。以Y2O3、Al(NO3)3·9H2O和柠檬酸为原料,采用柠檬酸凝胶燃烧法制备出黑色粉体,经1100℃烧结出尺寸小于50nm的YAG粉体。采用TG-DTA、XRD、FT-IR和TEM测试手段对YAG纳米粉体进行表征,采用谢莱公式计算出不同烧结温度下的晶粒尺寸。研究结果表明:YAG的析晶温度范围为850～900℃,烧结过程中出现赝YAG相物质,1050℃转变成纯YAG相,随着热处理温度的升高,晶粒呈线性增长,纳米粉体的TEM尺寸和采用谢莱公式计算的结果相一致。

Fabrication of Yttrium Aluminum Garnet (Y_3Al_5O_(12)) Nanometer Powder by Citrate-Gel Combustion Method

Transparent polycrystalline yttrium aluminum garnet (Y_3Al_5O_(12)), for its predominant optical, mechanical and chemical properties, is becoming a new generation of solid-state laser matrix material. The homogeneously dispersed, less agglomerated and superfine nanometer precursor powders are greatly favorable to fabricate highly transparent laser ceramics. The black powders are synthesized by using citrate-gel combustion method with Y_2O_3, Al(NO_3)_3·9H_2O and citric acid as raw materials, and the ytterium aluminum garnet(YAG) precursor powder with a size less than 50 nm is manufactured by calcining the black powders at temperature 1100℃.The YAG precursor powders are characterized by means of XRD, FT-IR and TEM and the grain sizes are calculated by the Scherrer's formula. It is exhibited that the forming temperature of YAG crystal phase is between 850～900℃,the pseudo-YAG crystalline appears during the calcination and then transforms to pure YAG at temperature 1050℃, the grain sizes linearly ascend with the calcination temperature increasing, the particle size observed under TEM is conformable to that calculated by Scherrer's formula.