在此研究中，本團隊參考許多鋁酸鍶正交晶相的合成法，最後選用最簡單、不耗時，且能產生勻相主體材料的尿素燃燒法來製作長余輝材料-Sr4Al14O25:Eu, Dy。在尚未摻雜稀土元素的情況下，以5 mole%硼酸添加為助熔劑，在1300 ℃，進行燒結得到鋁酸鍶正交晶相，但在摻雜稀土元素後，發現主體晶格的結構組成也跟著有所改變，我們針對稀土元素摻雜量、硼酸添加量及燒結溫度做調整，觀察並坦討改變合成參數對主體晶格和發光現象的影響，我們發現，雖然分別在燒結溫度1200 ℃以及硼酸濃度為10 mole%的情況下，鋁酸鍶正交晶相的比例均達到最高，但是在其發光性質上，卻不是以正交晶相純度最高的樣品，發光強度最高。此外，針對稀土元素摻雜量的討論，當銪離子濃度超過0.5 mole%後發光強度會因濃度淬減現象而降低，當鏑離子濃度超過銪離子五倍時，銪離子無法成為發光中心，受激發電子會以非輻射的形式散失，而在銪離子和鏑離子濃度均為0.1 mole%時，添加5 mole%硼酸，以1300 ℃燒結而成的產物發光強度最高。

In this study, our team find out many synthetic methods for strontium aluminate-orthorhombic crystal phase. Finally, urea combustion method was chose to make long afterglow material-Sr4Al14O25: Eu, Dy due to the advantage of simplicity, low time-consuming and homogeneous product. In the case of no rare earth elements doped, with 5 mole% boric acid as a flux, sintered at 1300 ℃, strontium aluminate-orthorhombic crystal phase can be obtained. However, in the case of rare earth elements doped, the main structure of the lattice changed. The effect of adjusting synthetic parameters on the lattice and luminescence of the host was observed and discussed. Although the proportion of orthorhombic phase of strontium aluminate was the highest when the sintering temperature was 1200 ℃ or the boric acid concentration was 10 mole%, but the highest luminous intensity did not happen at the highest proportion of orthorhombic phase. In addition, when the europium ion concentration exceeds 0.5 mole%, the luminous intensity will decrease due to concentration quenching phenomenon. When the concentration of dysprosium is more than twice the concentration of europium, europium ions will fail to become the luminous center, and the absorbed energy will be released in a non-radiative way by dysprosium. The phosphor performed the great luminous intensity and longest life-time when the concentration of europium and dysprosium were all 0.5 mole%, boric acid was added 5 mole% and sintered at 1300 ° C.

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