本研究首度透過固態反應法合成(Ca, IIA)3(VO4)2: Eu3+ (IIA=Mg, Sr, Ba)紅色螢光粉，並由實驗得知最佳燒結條件為1050 ℃持溫6個小時。為了提升Ca2.82(VO4)2: 0.12Eu3+的發光強度，我們試著將鈣離子以其它二價鹼土族離子取代，並發現當激發波長為465 nm，鎂、鍶、鋇離子於不同濃度下均能提升Ca2.82(VO4)2: 0.12Eu3+的PL強度。根據晶格常數的變化，我們推斷PL強度的增強可能是因為非中心對稱的Eu3+離子之對稱性降低所致；我們也發現鎂、鍶、鋇離子中，鋇離子的取代能夠提升最多的PL強度，並在9.9 mol%達到最佳值。經過計算，(Ca0.901Ba0.099)2.82(VO4)2: 0.12Eu3+的PL積分強度與Ca2.82(VO4)2: 0.12Eu3+比較起來，提升了1.36倍。本研究合成出的(Ca, Ba)3(VO4)2: Eu3+螢光粉與商用之適用藍光激發的硫化物紅色螢光粉比較起來，具備高化學穩定性與無硫污染的優勢。
我們利用Sm3+離子作為增感劑，成功地提升了(Ca0.901Ba0.099)2.82(VO4)2: 0.12Eu3+的發光強度。從Sm3+發射峰的衰減與Eu3+發射峰的增長，以及當Eu3+濃度遞增時，Sm3+離子之4G5/2→6H9/2躍遷的衰減行為分析，我們發現Sm3+→Eu3+的能量轉移。我們透過實驗計算出能量轉移效率、能量轉移機率與臨界濃度，並證實Sm3+→Eu3+屬於偶極—四極的反應機制。由於波長為465 nm的藍光能夠有效地激發 (Ca0.89Ba0.099)2.82(VO4)2: 0.02Sm3+, 0.12Eu3+紅色螢光粉，故此最佳化的螢光粉配合波長為450-470 nm的藍光二極體晶片，具備應用於「螢光粉轉換」白光發光二極體的潛力。此外，因為(Ca0.89Ba0.099)2.82(VO4)2: 0.02Sm3+, 0.12Eu3+紅色螢光粉的PLE與PL光譜與CuPc的吸收光譜具備良好的重疊，所以將此紅色螢光粉作為有機太陽能電池的下轉換層之螢光粉材料，有機會提升太陽能電池的性能。
我們也合成出新的適用紫外光激發的紅外光螢光粉Ca3(VO4)2: Yb3+。當激發波長為310 nm，此螢光粉產生位於983 nm的發射峰，並在Yb3+離子為14 mol%時達到最佳發光強度。從多晶矽太陽能電池的光譜響應圖，我們可以發現Ca3(VO4)2: Yb3+螢光粉具備高達約0.6 A/W的光譜響應變化，故此紅外光螢光粉對於提升多晶矽太陽能電池的光電轉換效率，乃一值得考慮的螢光粉材料。

In this thesis, the (Ca, IIA)3(VO4)2: Eu3+ (IIA=Mg, Sr, Ba) red phosphors were prepared by the solid-state reaction method for the first time, and the preferable sintered condition was obtained at 1050 oC for 6 h. To improve the luminescence intensity of Ca2.82(VO4)2: 0.12Eu3+, an attempt was made to replace Ca2+ by (IIA)2+. It was found either of IIA substitution enhanced the PL intensity of Ca2.82(VO4)2: 0.12Eu3+ at different (IIA)2+ contents under 465 nm excitation. According to the changes of the lattice constants, this enhancement may originate from the lower site symmetry of the Eu3+ ion in the center with noninversion symmetry. It was noted Ba2+ was the best choice of (IIA)2+ ions (IIA=Mg, Sr, Ba) in partial substitution for Ca2+ to enhance the PL intensity. And the optimum value of the Ba2+ content (y) was at 9.9 mol% in (Ca1-yBay)2.82(VO4)2: 0.12Eu3+. The (Ca0.901Ba0.099)2.82(VO4)2: 0.12Eu3+ phosphor showed 136% improved integrated intensity than that of the Ca2.82(VO4)2: 0.12Eu3+ phosphor. Compared to commercial oxysulfide and sulfide red phosphors suitable for blue excitation, our synthesized phosphor (Ca, Ba)3(VO4)2: Eu3+ has the advantages of no chemical instability and sulfur pollution.
The luminescence intensity of (Ca0.901Ba0.099)2.82(VO4)2: 0.12Eu3+ phosphor has been successfully further enhanced by adding the sensitizer, Sm3+ ion. We have discovered the energy transfer from Sm3+ to Eu3+ through the relative decline and growth in emission peaks of Sm3+ and Eu3+, respectively, as well as the variation of the decay behaviors of the Sm3+ 4G5/2→6H9/2 transition with the increasing Eu3+ content. The mechanism of the energy transfer from Sm3+ to Eu3+ was investigated and determined as the dipole-quadrupole interaction. The energy transfer efficiency, probability and the critical concentration in our Sm3+→Eu3+ system were also estimated. The optimized red phosphor (Ca0.89Ba0.099)2.82(VO4)2: 0.02Sm3+, 0.12Eu3+ is well-excited by the 465 nm blue lights, so it gives a potential for this phosphor to be applied on the phosphor-converted white LED with a blue chip (450-470 nm). Besides, the good overlap of the PLE and PL spectrum of (Ca0.89Ba0.099)2.82(VO4)2: 0.02Sm3+, 0.12Eu3+ phosphor and the absorption spectrum of CuPc indicates the potential use of the down-conversion phosphor coating to increase the performances of CuPc-based solar cells.
We also synthesized the new infrared Ca3(VO4)2: Yb3+ phosphors suitable for UV excitation. The infrared emission peak at 983 nm under excitation of 310 nm was observed and the optimum Yb3+ content was 14 mol%. And the sufficiently large SR’s variation (~0.6 A/W) of a poly-Si solar cell for this phosphor indicates this phosphor can be used as a potential candidate to increase the power conversion efficiency of poly-Si solar cells.

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