Ca_3Sc_2Si_3O_12:Ce^(3+),Nd^(3+)近红外荧光粉的制备和发光性质

SYNTHESIS AND NEAR-INFRARED LUMINESCENCE OF Ca_3Sc_2Si_3O_(12):Ce^(3+),Nd^(3+) PHOSPHOR POWDERS

利用高温固相法在弱还原气氛中制备了Ca3-x-ySc2Si3O12:xCe3+,yNd3+近红外发光荧光粉。用X射线衍射确定了样品的相结构,并研究了样品的可见及近红外激发和发射光谱,发光强度,荧光寿命等随Ce3+,Nd3+掺杂量的变化。结果表明:Ca3-x-ySc2Si3O12:xCe3+,yNd3+体系中Ce3+的发射光谱和Nd3+的激发光谱的有效重叠,说明存在Ce3+到Nd3+的高效能量传递,Ce3+,Nd3+的掺杂量分别为x=0.1和y=0.07时,Ca3-x-ySc2Si3O12:xCe3+,yNd3+粉体具有最强的近红外发射。与单掺Na3+的样品相比,Ca3Sc2Si3O12中掺杂Ce3+和Nd3+后,样品的近红外发光增强近400倍。此外,初步分析了Ca3-x-ySc2Si3O12:xCe3+,yNd3+中Ce3+到Nd3+的能量传递机理。

Ca3-x-ySc2Si3O12：xCe^3＋,yNd^3＋ phosphor powders were synthesized by the conventional solid-state reaction method in a reductive atmosphere.The structure of the phosphor was characterized by X-ray diffraction.The influences of Ce^3＋/Nd^3＋ concentration on the spectrum shape,fluorescence intensity and fluorescence lifetimes were investigated.The results show that the efficient energy transfer from Ce^3＋ to Nd^3＋ is due to good overlap between Ce^3＋ emission band and Nd^3＋ excitation bands,and the characteristic near-infrared luminescence of Nd^3＋ is remarkably sensitized by co-doping of Ce^3＋.With optimized Ce^3＋ content of x = 0.1 and Nd^3＋ content of y = 0.07,the Ca3-x-ySc2Si3O12：xCe^3＋,yNd^3＋ phosphor powder has the strongest near-infrared luminescence intensity,which is about 400 times stronger than that of sample with absence of Ce^3＋.The mechanism of the energy transfer from Ce^3＋ to Nd^3＋ in Ca3-x-ySc2Si3O12：xCe^3＋,yNd^3＋ phosphors is also discussed briefly.