Research On Synthesis Of （Nd,Yb）:Sc₂O₃ Nano-ceramic Powders

SC2O3 transparent ceramics exhibit many merits, such as high bulk refractive index, high band gap, high thermal conductivity, high melting point and excellent chemical stability. Furthermore, rare earth ions can be doped into the framework of cubic SC2O3. Since Nd3+ and Yb3+ show good laser emission characteristics, the doped transparent ceramic can be employed as laser light emitting materials. The focus of transparent ceramic preparation is powder synthesis and transparent ceramics sintering technology. The preparation of nanopowder with high purity and homogeneous chemical composition is a key step to obtain transparent ceramics. This paper mainly studied the synthesis process of (Nd, Yb):Sc2O3 nanopowders.The precursors of Sc, Nd and Yb with different molecular weight were prepared through positive titration and back titration with (CH2)6N4 as precipitant; (Nd, Yb):Sc2O3 nanopowders with polygon and uniform particle distribution were obtained in high temperature box type resistance furnace at 1100℃. Besides, approximately spherical and well dispersed (Nd, Yb):Sc2O3 nanopowders were prepared with CO(NH2)2 as precipitant. Using (CH2)6N4 as precipitant, the precursors of (Nd, Yb):Sc2O3 were prepared by microwave synthesis, and then (Nd, Yb):Sc2O3 nanopowders were both obtained using two heating methods which were microwave irradiation at 900℃ and calcination in high temperature box type resistance furnace at 1100℃. The precursors and (Nd, Yb):Sc2O3 nanopowders were characterized by thermogravimetric-differential scanning calorimetry, transmission electron microscopy analysis, ICP-MS spectrum analysis, X-ray diffraction and infrared spectrum analysis.The results showed that the particle sizes of (Nd, Yb):Sc2O3 nanopowders were between 20-40nm with good dispersivity and uniform particle distribution. At first, the precursors prepared by microwave synthesis were carried out (Nd, Yb):Sc2O3 nanopowders by microwave irradiation. Also the precursors prepared by homogeneous precipitation were carried out (Nd, Yb):Sc2O3 nanopowders by calcination in high temperature box type resistance furnace. Compared with the latter, the former (Nd, Yb):Sc2O3 nanopowders had not only good dispersivity and small particle size, but also shorter reaction time.