钆镓石榴石纳米粉体的合成过程研究

Study on Synthesis Process of Nano-Powders of Gadolinium Gallium Garnet

研究了工艺条件对氨水-碳酸氢铵共沉淀法合成钆镓石榴石（Gd3Ga5O12,GGG）纳米粉体的微观结构和物相变化的影响,并利用热重-差示扫描量热分析（TG-DSC）、X线衍射（XRD）、场发射扫描电子显微镜（FESEM）、红外光谱分析（IR）等测试手段对前驱体及烧成粉体的结构和形貌进行了分析表征。结果表明,采用正滴定方式,在750-800℃下煅烧4h可得到粒度小于100nm纯相GGG粉体（未见任何其他中间相）,属于立方晶体结构,其空间群为Ia3d,晶格常数a=1.237 58nm。该粉体具有良好的分散性和烧结活性。

Nano-sized powders of gadolinium gallium garnet（Gd3Ga5O12,GGG）have been prepared by a co-precipitation method with NH3-NH4HCO3 as precipitant agent.The effects of process conditions on the microstructure and phase compositions were investigated.XRD,FTIR,FE-SEM,TEM,and thermal analysis（TG-DSC）have been used to characterize the phase transition and morphology of the synthesized powders.The results show that the wellcrystallized pure phase GGG powders with the particle sizes of less than 100 nm were obtained at 750-800 ℃for4h,without any intermediate phases formed during the process by using the positive titration method.The lattice constant was a=1.237 58nm;the patterns of the samples exhibited the cube structure,and the space group was Ia3 d.The resultant nano-sized GGG polycrystalline powders showed good dispersion and excellent sintering activity.