本研究以固態反應法製備Li2MgTi3O8作為主體材料，Mn4+離子作為發光中心之紅色螢光粉(Li2MgTi3O8：Mn4+)，且藉由Al3+、Ge4+置換Ti4+以及Co2+置換Mg2+位置，探討其粉體結構與光致發光性質等特性。
第一部分先以密度泛函理論為基礎之ab initio計算，建構出Al3+、Ge4+和Co2+離子參雜之Li2MgTi3O8:Mn4+能態密度圖。其結果預測出Ge4+或Co2+的參雜由於能帶重疊可以作為敏化劑，藉由共振來減少多重聲子躍遷所造成的能量損失，而提升光致發光強度。
第二部分探討在不同蝦燒溫度下，Li2MgTi3O8:Mn4+之光致發光特性，其結果顯示隨著溫度的上升，有結晶性提升、顆粒增大以及發光強度提升的趨勢，而在1100℃時有最佳結晶性和最高發光強度。
第三部分探討不同Mn4+參雜濃度之影響，當Mn4+參雜濃度為0.1%時可得到最強的發光強度，由Raman結果推測可能為較佳的結晶性。SEM結果顯示Mn4+參雜濃度對於粉體表面形貌沒有顯著影響。Li2MgTi3O8:0.1%Mn4+在325 nm激發光源下，可得到680 nm的紅光，激發光譜涵蓋300-550 nm，可有效地以紫外光、藍光LED或近紫外光激發，擴散反射光譜和吸收光譜可輔助激發光譜之結果。
第四部份結果顯示參雜Al3+離子會降低發光強度，參雜0.1%Ge4+離子可增加約55%發光強度，而參雜0.5% Co2+離子發光強度增加316%，最強放射峰值在Co2+離子高濃度時紅移至696 nm，這是由於能隙值下降使得放射波長增加。這些結果和第一部份計算結果相符。

Mn4+ doped Li2MgTi3O8 non-rare-earth red phosphor were discussed theoretically and experimentally. Ab initio calculation of density of states (DOS) based on density function theory (DFT) were conducted first to predict the effect of doping Mn4+ and sensitizers (Ge4+ and Co2+). The overlapped states indicated that Ge4+ and Co2+ could be the sensitizers to enhance the emission intensity. Then the phosphor was synthesized by conventional solid-state reaction. The effects of calcination temperature and Mn4+ doping concentration were investigated to determine the optimal preparation conditions. Through the analysis of XRD and PL, it can be found that the crystallinity plays an important role in the luminescent intensity. In addition, the emission intensity increase 55% and 316% after doping of Ge4+ and Co2+, respectively. The red-shift of emission peak in Co2+-doped PL spectra is ascribed to the band-narrowing, which is confirmed by the results of UV-vis. In this work, the DOS calculation is all proved by the experimental results.

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