研究了化学共沉淀法合成Nd:Sc2O3纳米粉的工艺。以Sc2O3为基质材料,掺杂0.5%(原子分数)的Nd3+,添加适量聚乙二醇(PEG)和(NH4)2SO4作为分散剂,以氨水(NH3.H2O)和碳酸氢铵(NH4HCO3)混合溶液作复合沉淀剂,采用化学共沉淀法获得了碱式稀土碳酸盐前躯体,在1100℃下煅烧该前躯体4 h,制备出性能良好的Nd:Sc2O3纳米粉。采用热重-差热分析仪(TG/DSC)、红外光谱分析仪(IR)、X射线衍射仪(XRD)、透射电子显微镜(TEM)等测试手段对Nd:Sc2O3前躯体和煅烧后的粉体进行表征。实验结果表明:在室温下,用氨水和碳酸氢铵混合溶液作为复合沉淀剂合成出的前躯体为碱式稀土碳酸盐。通过XRD和EDS能谱分析,Nd3+完全固溶于Sc2O3的立方晶格中,这将有利于制备激光透明陶瓷。在1100℃的温度下煅烧此前躯体得到的Nd:Sc2O3纳米粉具有颗粒粒度小(约50 nm)、分散性好、团聚程度轻、结晶良好的性能。因此,采用此工艺合成的粉体将有可能制备出的Nd:Sc2O3透明陶瓷。
The synthesis of Nd∶ Sc2O3 nanopowders by co-precipitation method were investigated.The precursors of rare earth basic carbonate were prepared by co-precipitation method using Sc2O3 as the matrix material,doping 0.5%(atom fraction) Nd3+ and adding PEG and(NH4)2SO4,and using ammonium hydroxide(NH3 · H2O) and ammonium hydrogen carbonate(NH4HCO3) as the mixed precipitant.After the precursors were calcined at 1100 ℃ for 4 h,the Nd∶ Sc2O3 nanopowders were synthesized.The powders and calcined nanopowders were characterized by thermogravimetry traces /differential thermal analysis(TG/DSC),Infrared spectra(IR),X-ray diffractometry(XRD),and transmission electron microscope(TEM),respectively.The results showed that at room temperature,the precursors prepared by using ammonium hydroxide(NH3 · H2O) and ammonium hydrogen carbonate(NH4HCO3) as the mixed precipitant were rare earth basic carbonate.The Nd3+ dissolved completely in the cubic Sc2O3 by XRD and EDS,which would be beneficial to the synthesis of laser transparent ceramic.The nanopowders with an average size of about 50 nm were loosely dispersed,slightly agglomerated and well-crystallized.Therefore,Nd∶ Sc2O3 transparent ceramic would be synthesized by using these nanopowders.