SrNb_2O_6:Eu~(3+), Bi~(3+)红色荧光粉的固相合成及发光性质研究

采用高温固相反应法合成稀土离子Eu~(3+)掺杂的铌酸锶红色荧光粉,对其晶体结构和荧光性质进行了X射线衍射(XRD)、荧光光谱(PL)的表征,同时研究了共激活剂Bi~(3+)对SrNb_2O_6:Eu~(3+)发光性质的影响.结果表明,在1 200 ℃焙烧后可得到SrNb_2O_6纯相;Sr_(1-x)Nb_2O_6:Eu_x~(3+)荧光粉可以被395 nm近紫外光有效激发,发射峰以Eu~(3+)的5D_0→7F_2(614 nm)电偶极跃迁为最强峰,Eu~(3+) 在SrNb_2O_6中应处于偏离反演对称中心的格位,当x=0.15时,SrNb_2O_6:Eu~(3+)在614 nm处的发光强度最大;共激活剂Bi~(3+)的掺入可以增强SrNb_2O_6:Eu~(3+)荧光粉在325 nm左右激发峰的强度.

Preparation and Photoluminescence Properties of SrNb_2O_6:Eu~(3+), Bi~(3+) Red-Emitting Phosphor

Rare earth Eu~(3+)-doped SrNb_2O_6 red-emitting phosphor was prepared by high temperature solid-state reaction.Structure and photoluminescence properties (PL) of the samples were characterized by X-ray diffraction (XRD),fluorescence spectrophotometer,respectively,meanwhile the effect of the co-activator Bi~(3+) on the PL of the SrNb_2O_6:Eu~(3+) phosphor was studied in detail.Results showed that the pure phase of SrNb_2O_6 could be available at the calcination temperature of 1 200 ℃.Sr_(1-x)Nb_2O_6:Eu_x~(3+) phosphors could be effectively excited by the near-UV irridiation (395 nm) and emit red light at 614 nm due to the forced electric dipole 5D_0 → 7F2 transitions on Eu~(3+),which indicated that Eu~(3+) occupied the non-inversion the symmetry sites in the SrNb_2O_6 host lattice.When the content of doped-Eu~(3+) was up to 15%,the PL intensity of SrNb_2O_6:Eu~(3+) reached the highest.So the Sr_(0.85)Nb_2O_6:Eu_(0.15)~(3+) phosphor could be a promising red component for possible applications in the white LED.The addition of the co-activator Bi~(3+) increased the PL intensity of the SrNb_2O_6:Eu~(3+) phosphor at about 325 nm,while decreased the PL intensity at 395 nm.