為提高鋁酸鍶鈣螢光粉體之發光效率，並獲得具不同色度座標之白光螢光粉，本研究以二種檸檬酸法製備粉體，檢討下列實驗變因對螢光粉體之合成及發光性質之影響：包括(1) 檸檬酸錯合物法(檸檬酸/金屬陽離子之莫耳比vs.酸鹼值)、(2) 檸檬酸凝膠法(檸檬酸/金屬離子之莫耳比vs.乙二醇/檸檬酸之莫耳比)、(3) Eu3+¬ 離子之取代量、(4)錳離子之取代量。
以檸檬酸/金屬陽離子之莫耳比≧2、pH=2或檸檬酸/金屬陽離子之莫耳比≧2、乙二醇/檸檬酸之莫耳比≧1的條件所製得的前驅物為非晶質，大部分前驅物經1000℃/ 8h煅燒即可成為含高溫相六方SrAl2O4和單斜CaAl2O4之鋁酸鍶鈣螢光粉體。當Eu2+進入此兩種主體晶格時，便會在PL圖譜形成綠光(λp=520nm)和藍光(λp=440nm)發射帶。在檸檬酸錯合物法中，1300℃及1400℃煅燒所合成之螢光粉體，其藍光發射帶之發射強度會隨pH值之增加而變大；而檸檬酸凝膠法中，經1400℃二階段煅燒所合成之螢光粉體，其PL積分強度會隨乙二醇添加量之增加而降低。在相同煅燒條件下，檸檬酸凝膠法所合成之螢光粉體，其PL積分強度較檸檬錯合物法所合成者強。
在製備摻Eu3+之鋁酸鍶鈣螢光粉體實驗中，螢光粉體主要由六方SrAl2O4、單斜CaAl2O4及EuCaAl3O7相所組成。此螢光粉體主要發出616nm、598nm及587nm之紅光，其發射強度隨Eu3+取代量之增加而增強，當在Eu3+ 取代量大於16 mol%後，由於濃度淬滅效應，紅光發射強度隨Eu2+取代量之增加而降低。藉由混合摻有Eu2+及Eu3+之二種螢光粉體可提升演色性。
在製備摻錳、銪離子之鋁酸鍶鈣螢光粉體實驗中，僅摻有Mn2+之粉體無法以383nm或350nm激發，同時摻有錳、銪離子之鋁酸鍶鈣螢光粉受383nm激發時則可發光，其發射峰各為Eu2+所發射之440nm、520nm及Mn2+所發出之480nm。摻Mn2+、Eu2+之鋁酸鍶鈣螢光粉，其PL積分強度較僅摻Eu2+者強。螢光粉體之整體PL積分強度、440nm及520nm兩發射峰強度隨Mn2+添加量之增加而降低，但480nm發射峰則會增加。
在1300℃~1400℃煅燒溫度範圍內，所有螢光粉之PL發射強度會隨煅燒溫度提升而增加，其中以Eu2+摻雜濃度為1 mol%、Mn2+摻雜濃度為0.5 mol%之前驅物，經1400℃二階段煅燒之樣品具有最大之PL積分強度；摻雜18 mol% Eu3+之螢光粉體與摻雜1 mol% Eu2+之螢光粉體依重量比2:1所混合之混合粉體，且有最佳之演色性，最接近白光。

In order to increase the emission intensity and gain the white light phosphor, strontium-calcium aluminate phosphors were synthesized by citric acid method in this study. Influence factors of synthesis & luminescence for phosphors were discussed : as (a) Citrate complex method (ratio of citric acid/metal ions vs. pH value), (b) Citrate gel method (ratio of citric acid/metal ions vs. ratio of ethylene glycol/citric acid), (c) Amount of Eu3+ ions, (d) Amount of Mn2+ ions
The precursors were amorphous when the ratio of citric acid/metal ion≧2, pH=2 or the ratio of citric acid/metal ion≧2, the ratio of ethylene glycol/ citric acid≧1. Strontium-calcium aluminate phosphors were obtained and composed of monoclinic CaAl2O4 and hexagonal SrAl2O4 after calcining ar 1000℃/8h for most precursors. It means citrate complex method and citrate gel method can lower the synthesis temperature about 300~400℃. When Eu2+ ions doped into these two host lattices, phosphors showed blue (λp=440nm) and green (λp=520nm) emission bands in PL spectra. The 440nm emission intensity increased with pH value increased in citrate complex method during 1300℃~1400℃ calcination temperature. The PL integral intensity decreased with the amount of ethylene glycol increased in citrate gel method at 1400℃ calcination temperature.. Phosphors synthesized by citrate gel method showed higher PL integral intensity than those synthesized by citrate complex method.
In experimental of synthesizing strontium-calcium aluminate phosphors with Eu3+, phosphors were composed of monoclinic CaAl2O4, hexagonal SrAl2O4, and EuCaAl3O7. These phosphors emitted 616nm, 598nm and 587nm red light, and and the PL emission intensity increased with amount of Eu3+ increased during Eu3+ = 1~16 mol%. Them, because of concentration quehching, PL emission intensity decreased with amount of Eu3+ increased when Eu3+>16 mol%. By mixing red phosphors with blue-greed phosphors, color rendering index were increased.
In experimental of synthesizing strontium-calcium aluminate phosphors with Mn2+, Mn2+-doped powder didn’t emit, and Eu2+ & Mn2+-doped phosphors showed 440nm、520nm emission band from Eu2+ and 480nm emission band from Mn2+. For all the Eu2+, Mn2+-doped phosphors, PL integral intensity were large then phosphors only doped Eu2+.When increasing the amount of Mn2+, PL integral intensity, 440nm and 520nm emission intensity decreased, but 480nm emission intensity increased.
For all these phosphors calcinated during 1300℃~1400℃, 1 mol% Eu2+ & 0.5 mol% Mn2+-doped phosphor showed the maximum PL integral intensity, and mixing powder of twice 18 mol% Eu3+-doped phosphor and 1 mol% Eu2+-doped phosphor showed the best color rendering and closest to white light center.

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