本研究使用高溫固態反應法製備Y2MgTiO6+(YMTO)雙鈣鈦礦螢光材料，並選用Sm3+與Dy3+分別作為活化劑取代材料中Y3+為發光中心。探討Y2MgTiO6:Sm3+紅光螢光粉之晶體結構、光學特性與熱穩定性，並探討Y2MgTiO6:Dy3+螢光粉之晶體結構、光學特性與熱穩定性，最後共摻雜Y2MgTiO6:Dy3+/Sm3+使螢光粉末具備紅光波段製備出可調式暖白光。
第一階段將先使用第一原理計算穩定結構之YMTO、YMTO:Sm3+與YMTO:Dy3+並計算摻雜少量活化劑後，材料架構之穩定度與活化劑離子對能階與能態密度的影響。當摻雜活化劑後，可見YMTO螢光材料之能階由3.3eV下降至摻雜Sm3+之3.0eV與Dy3+之2.3eV，並可由能帶密度觀察到能階下降主要由活化劑所貢獻。
第二階段將研究部不同鍛燒溫度對螢光粉末YMTO:Sm3+光學特性與晶體結構之影響，當煆燒溫度低於1400°C可由XRD繞射分析圖觀測到二次相訊號，而1500°C以上之螢光材料無二相產生代表成功合成此材料，但1600oC之螢光材料SEM分析顯示融化現象，這會劣化其發光特性，並使用PL放射光譜進行放射波段的光學特性探討，可觀測到1500°C之鍛燒溫度擁有最佳的放射強度，使1500°C為YMTO螢光材料之最佳鍛燒溫度。
第三部分則研究不同摻雜濃度下以Sm3+製備之紅光螢光粉晶體結構、光學特性與熱穩定性。首先使用XRD、GSAS、SEM進行晶體結構之探討，可見至7mol% Sm3+摻雜濃度為止皆成功合成並且無二次相產生，SEM也可觀測到球形結構有利於減少表面反射，接著以PL、PLE、CIE進行光學特性之探討，可見放射光譜於3mol%擁有最佳放射強度，緊接著發生濃度淬滅，並於602 nm擁有最好的放射強度。再以最佳強度YMTO:3Sm3+進行熱淬滅分析，可見於425K之LED工作溫度依然可以維持81.9%之初始強度並且優於其他以Sm3+作為活化劑之螢光粉。
第四部份則是研究以Dy3+作為活化劑之螢光材料，晶體結構、光學特性、熱穩定性之探討。同樣以XRD、GSAS、SEM研究其晶體結構，可見至5mol%摻雜濃度為止皆可成功替換材料中Y3+並且無任何二次相產生，SEM也成圓球狀之晶粒。光學特性則是以PLE、PL、CIE進行分析，於放射光譜中可見575 nm為Dy3+之最佳強度波長，並於4mol%擁有最佳放射強度，接著發生濃度淬滅使強度下降，而不同摻雜濃度僅影響放射強度不影響放射光譜位置與位移。最後探討最佳濃度YMTO:4Dy3+之熱穩定性，可觀察到相較於其他Dy3+之螢光粉末，該螢光材料擁有最佳的放射強度，並且可以於425K之LED工作溫度維持92.5%之放射強度
最後利用共摻雜Sm3+與Dy3+至YMTO主體材料中使YMTO:Dy3+/Sm3+擁有紅光區域之波段使色溫由未摻雜之4115K下降至3302K。低色溫的暖白光螢光粉解決了冷白光螢光粉高色溫造成對人眼不適的缺點，並擁有較佳的顯色性，製備出可調之YMTO:Dy3+/Sm3+暖白光螢光粉，並且於425K之LED工作溫度可維持76.8%之放射強度。

Y2MgTiO6:Sm3+/Dy3+ double-perovskite phosphors were synthesized using the high-temperature solid-state reaction method, and their luminescence properties were examined through various techniques, including Rietveld refinement, excitation and emission spectra, Commission Internationale de l'Eclairage (CIE) analysis, and band gap simulation. The emission spectra of Y2MgTiO6 (YMTO) doped with Sm3+ and Dy3+ exhibited maximum peaks at 602nm and 575nm, respectively, when excited at 325nm. The CIE coordinates of YMTO:1Dy were determined to be (0.3771, 0.3804), and the correlated color temperature (CCT) was 4115K, indicating its suitability for warm white light applications. The CCT values were adjustable to 3719K and 3302K by adding 1 and 3 Sm3+ ions, respectively, to the Sm3+/Dy3+ co-doped YMTO, further enhancing its potential for use in warm white light-emitting diodes (WLEDs). Therefore, YMTO: Sm3+/Dy3+ phosphors show promising characteristics for use in warm WLEDs.

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