本實驗以固相合成法製備YTiNbO6:RE(RE=Dy、Er、Pr)之螢光粉，及針對YTiNbO6:Dy同時添加Ta5+離子進行共摻雜，探討其材料合成、摻雜濃度、主體變化、燒結條件對螢光材料的晶體結構及螢光性質的影響。
　　由實驗可知，利用固相合成製備YTiNbO6:RE，在1300℃可得穩定的Euxenite相之YTiNbO6 (PDF no.83.1318) ，並由吸收光譜可得光學能隙(band-gap)Eg=3.65eV(339.7nm)。YTiNbO6:Dy在以353nm為激發光源激發下，可同時發出482nm(4F9/2→6H15/2)的藍光和579nm(4F9/2→6H13/2)的黃光，以1300℃煆燒24小時的YTiNbO6:0.05Dy螢光粉體具有最佳的發光強度，色度座標為(0.31,0.37)，坐落於白光區內。而YTiNbO6:Dy、Ta在以基質(290nm)激發下，可發現除了來自Dy3+離子4f軌域間的電子躍遷，尚有一來自主體材料中NbO6所引發的寬帶發光，範圍在400~670nm。且隨著Ta5+離子的摻雜，寬帶發光的強度隨之增強，直至Ta5+完全取代Nb5+時，寬帶發光具有最佳發光強度。這代表在晶格中TaO6原子團比NbO6更能貢獻在此寬帶發光上。
　　YTiNbO6:Er螢光粉體於378nm紫外光源激發下，其放射光主要為520~570nm的黃綠光(2H11/2→4I15/2、4S3/2→4I15/2)，其發光強度隨Er3+離子摻雜濃度增加而提升，並於摻雜濃度為10mol%時，螢光粉體具有最佳的發光強度，其色度座標為(0.29, 0.67)，坐落於黃綠光區。YTiNbO6:Pr螢光粉體於491nm藍光光源激發下，發光集中在585~645nm的紅光，分別對應到1D2→3H4及3P0→3H6的能階躍遷之發光，摻雜Pr3+離子濃度為0.5mol%之螢光粉體具有最佳的發光強度，CIE色度座標為(0.67,0.33) ，坐落於紅光區。

　　YTiNbO6:RE(RE=Dy、Er、Pr) and YTiNbO6:(Dy,Ta) phosphors were synthesized by solid state reaction in this work. The effects of rare earth ion concentration, distortion of host, sintering temperature, and the grain size, and morphology on the photoluminescent properties were investigated and optimized.
　　YTiNbO6:RE compounds of the Euxenite structure (PDF no.83.1318) were successfully synthesized by sintering at 1300℃. The fundamental absorption edge was calculated from the absorption spectra to be at 339.7nm, corresponding to the band-gap energy of 3.65eV. Under the excitation wavelength of 353nm, the dominant emission clusters were located around 482nm and 579nm, arising from the Dy3+ transitions 4F9/2→6H15/2 and 4F9/2→6H13/2 in YTiNbO6:Dy. The optimum doping level of Dy3+ in YTiNbO6:Dy was found to be 5mol%. The CIE chromaticity coordinate was at (0.31,0.37) for YTiNbO6:Dy, corresponding to a color tone of near-white. Under the charge-transfer excitation at 290nm, a broad emission at 400~670nm was observed in addition to the sharp lines from the Dy3+ transitions. This broad emission is thought to come from the NbO6 group of the host. When Nb was substituted by Ta, the road emission was increased with the Ta concentration and reached maxima for the pure Ta compound, i.e. YTiTaO6:Dy, indicating that TaO6 emits more efficient than NbO6 at this wavelength region.
　　The optical spectra of YTiNbO6:Er is dominated by the strong emission centered at 558nm. The optimum concentration for Er3+ was found to be 10 mol%. The CIE (x,y) coordinate of YTiNbO6:Er was calculated to be at (0.29,0.67), corresponding to the color tone of yellowish green. The optical spectra of YTiNbO6:Pr were characterized by a strong emission at the 615 nm, which came from the Pr3+ 1D2→3H4 and 3P0→3H6 transitions. The optimum concentration for Pr3+ was determined to be 0.5 mol%, and the (x,y) coordinate was at (0.67,0.33), having the red color.
Keyword: phosphor, euxenite structure

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