纳米发光材料Re(Nd，Yb)：GdAlO3的合成、结构及发光性能

Synthesis,structure and luminescent properties of nanoscaled luminescent material Re(Nd,Yb)∶GdAlO_3

采用共沉淀方法,以Gd2O3、Al(NO3)3.9H2O、Nd2O3(Yb2O3)为原料、氨水为沉淀剂,合成了Nd∶GdAlO3(5%(原子分数))和Yb∶GdAlO3(5%(原子分数))纳米多晶粉末,采用X射线衍射(XRD)和Rietveld精修方法对晶体结构进行了研究,采用场发射扫描电镜(FESEM)对晶体的形貌进行了研究,同时对晶体的发射光谱进行了测量。XRD结果表明,在较低的煅烧温度和较短的煅烧时间下(1000℃,保温3h)可获得纯Nd∶GdAlO3和Yb∶GdAlO3晶相,同时晶粒尺寸随着煅烧温度的升高而增大。Rietveld精修结果表明半径较大的Nd3+离子的掺杂,使GdAlO3晶体结构有从正交相向四方相转变的趋势。FESEM结果表明,颗粒大小均在纳米尺寸范围之内,且具有较好的分散性。在Nd∶GdAlO3晶体的发射光谱中,在927、1077和1335nm附近出现的3个发射峰分别对应于Nd3+的4F3/2→4I9/24、F3/2→4I11/2和4F3/2→4I13/2跃迁;在Yb∶GdAlO3晶体中,主要发射峰波长位于979、997和1028nm处,其中1028nm处为最强发射峰,对应于Yb3+的2F5/2→2F7/2跃迁。

Nanoscaled powders Nd ： GdAlO3 （Sate） and Yb ： GdAlO3 （Sate） were synthesized by co-precipitation method with Gd2O3 ,Al（NO3）3 · 9H2O,Nd2O3 and Yb2O3 as the starting materials and aqueous ammonia as precipitator. The crystal structures of Nd ： GdAlO3 and Yb ：GdAlO3 were studied by Rietveld refinement of Xray diffraction （XRD）, the morphology of the powders were studied by FESEM, and their emission spectra were also measured. The results of the XRD showed that the pure Nd ： GdAlO3 and Yb ： GdAlO3 phases were obtained at lower temperature （1000℃） with shorter calcinating time （3h） and the average particle size of powder increases with the increase of the calcination temperature, the results of the Rietveld refinement showed that GdAlO3 crystals has the transformation tendency of orthorhombic phase to tetragonal phase. The FESEM showed that the powder are in nano-size and are better dispersed. In the emission spectrum of Nd ： GdAlO3 crystal, the peaks at 927,1077 and 1335nm are attributed to the ^4F3/2→^4I9/2, ^4F3/2→^4 I11/2 and ^4 F3/2→^4I11/2 transition of Nd^3＋ ion respectively; In the emission spectrum of Yb ： GdAlO3 crystal, the peaks at 1028nm corresponded to the ^2F5/2→^2FT/2 transition of Yb^3＋ ion.