本研究以固相反應法製備Y10W2O21: Eu3+螢光粉，探討不同陽離子(La3+, Lu3+, Sc3+) 的摻雜或M2WO4 (M = Li, Na, K)助熔劑的添加對Y10W2O21: Eu3+螢光粉結構與發光性質之影響。實驗結果是以熱重/熱差分析儀、粉末X光繞射儀、場發射電子顯微鏡、吸收光譜及螢光光譜儀等分析之，其中螢光光譜包括激發及放射光譜、衰退時間、熱穩定性與量子效率量測。
研究結果顯示，(Y1-xEux)10W2O21 (x = 0.01-0.3)螢光粉可於空氣中1400 °C並持溫6小時煆燒而得，其結晶性佳，晶粒大小200-500 nm；激發光譜顯示此螢光粉可以近紫外光 (392 nm) 或藍光 (465 nm) 激發；而產生的兩個主要放射峰，位於612 nm與627 nm之5D0-7F2躍遷，此結果是因Eu3+離子取代擁有兩個配位數的Y3+離子，而造成不同能階分裂的躍遷所致。其放射強度與量子效率隨Eu3+摻雜量之增加而增強，直到Eu3+摻雜量達22.5 mol% 後才產生濃度淬滅。
(Y0.99-xMxEu0.01)10W2O21摻雜不同陽離子 (M = La3+, Lu3+, Sc3+) 的研究結果顯示，摻雜量x = 0.01-0.25時，均為單一Y10W2O21斜方晶之繞射峰；而La3+與Lu3+之摻雜量為x = 0.5-0.99時，其相分別轉變成La6WO12立方晶與Lu6WO12菱方晶結構。高摻雜量 (x = 0.5-0.99) 的粉末，因晶體結構的轉變，使得其激發光譜圖之CTB隨陽離子之離子半徑的增加 (如La3+) 而red shift，其放射光強度因而減弱；反之，隨陽離子之離子半徑的減少 (如Lu3+) 而blue shift，使得其放射光強度因而增強。
添加M2WO4 (M = Li, Na, K) 助熔劑的研究結果顯示，在相同的煆燒條件下，Li2WO4助熔劑會造成Y30W8O69二次相的生成；而添加30 wt% Na2WO4與K2WO4助熔劑皆可生成單一之Y10W2O21斜方晶相，且可避免顆粒之團聚。Na2WO4與K2WO4助熔劑可降低起始原料開始反應的溫度，並於煆燒階段幫助Y10W2O21: Eu3+螢光粉的溶解-再結晶過程，使顆粒大小分別成長到9 μm與1 μm。粉末XRD之半高寬因助熔劑添加量的增加而降低，表示其結晶性因而變佳。添加Na2WO4與K2WO4助熔劑之Y10W2O21: Eu3+螢光粉其放射光強度與未添加者相比分別增加190% 與150%。

Eu3+-doped fluorite-related yttrium-tungsten oxide Y10W2O21 (5Y2O3·2WO3) was prepared using vibrating-mill-mixed powder and solid-state reactions. The synthesis temperature was investigated by thermogravimetric/differential thermal analysis and X-ray diffraction. The morphology of the phosphor was confirmed by scanning electron microscope (SEM) measurement. The photoluminescence (PL) properties, including the excitation and emission spectra, decay curves (lifetime), thermal stability and quantum efficiency were investigated.The PL emission intensity was increased with Eu3+ content up to about 22.5 mol% and then decreased due to the concentration quenching effect. The major intensity emission wavelengths, located at 612 nm and 627 nm for excitation at 392 nm, were attributed to replacement of the Eu3+ ions with 7 or 8 coordination sites of Y3+ ions.
In order to enhance the luminescence properties of Y10W2O21: Eu3+ phosphors, the effect of codoping cation (La3+, Lu3+, Sc3+) or fluxes on the structure and photoluminescence properties of Y10W2O21: Eu3+ phosphors were also investigated. The results of codoping cation showed that the orthorhombic structure of Y10W2O21 changed to cubic La6WO12 and rhombohedral La6WO12 when the high codoping ratio. The CTBs of the excitation spectrum would shift as the structure change due to the difference of the cation radius. In the study of tungstate fluxes, the samples with Na2WO4 and K2WO4 fluxes were in agreement with those of the Y10W2O21 phase In addition, the experimental results indicate that the particle size and morphology of the Eu0.5Y9.5W2O21 phosphors depend on the type and content of tungstate flux. The luminescence intensities of the phosphors were effectively enhanced by the tungstate flux.

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