鈣鈦礦系列的材料由於其優異的光電性能，包括高光致發光量子產率、窄發光半高寬和可調整發光波長，可應用於太陽能電池、雷射、光伏元件以及發光二極體等領域，成為近年來學術界及產業界一大研究熱點。儘管如此，紅色發光的全無機鈣鈦礦CsPb(BrxI1-x)3 材料由於對濕氣、空氣敏感的缺點，故極大地限制其未來應用，因此改善材料的穩定性是目前研究的重點之一。
本研究採用無需使用極性溶劑的熱注法製程，並搭配不同配體油胺及3-氨基丙基三乙氧基矽烷，藉由調整鹵素比例，合成出不同發光波長的溴碘混合型鈣鈦礦CsPb(BrxI1-x)3量子點。此外，為了增加量子點的應用價值，本研究選擇最接近學術界在633nm處紅色發光之研究的鹵素比例，加入易加工的聚甲基丙烯酸甲酯基質中製備成紅光量子點光致發光薄膜，並分別對其進行發光性質、耐候性與特性分析及比較，研究結果顯示3-氨基丙基三乙氧基矽烷有助於增強量子點薄膜穩定性。然而，量子點薄膜暴露在空氣和濕氣中的穩定性仍需改善。
因此，本研究進一步再於3-氨基丙基三乙氧基矽烷為配體的量子點中引入四乙氧基矽烷進行溶膠-凝膠反應，在量子點外圍包覆更緻密的二氧化矽以隔絕空氣與濕氣，有效提升薄膜的穩定度。最後，為增強薄膜發光的均勻性，研究摻入二氧化矽奈米球以增加薄膜的米氏散射效率，結果顯示薄膜的光致發光量子產率隨著二氧化矽奈米球摻入量增加而提升，最終成功地製備出光致發光量子產率高達45%且能維持一個月發光的紅光量子點薄膜，未來可望應用於白光發光二極體和顯示器背光模組等領域。

Perovskite materials due to their excellent photoelectric properties, including high PLQY, narrow FWHM and adjustable luminescence wavelength, can be applied to solar cells, lasers, photovoltaic devices, and LEDs, etc., have become a major research hotspot in academia and industry in recent years. Nevertheless, the red-emitting all-inorganic perovskite CsPb(BrxI1-x)3 is sensitive to moisture and air, which greatly limits its commercial application. Therefore, improving the stability of the material is one of the focuses of current research.
In this study, bromine iodine mixed perovskite CsPb(BrxI1-x)3 quantum dots (QDs) with different luminescent wavelengths were synthesized by hot injection method without polar solvent, with different ligands OLA and APTES ((3-Aminopropyl) triethoxysilane) and adjusting the ratio of halogen. In addition, in order to increase the application value of QDs, the ratio of halogen which is closest to the academic research of red luminescence at 633 nm was selected and added into PMMA matrix to prepare films. The luminescent properties and stability of the films were analyzed and compared. The results show that APTES is helpful to enhance the stability of films. However, the stability of the film exposed to air and moisture still needs to be improved.
Therefore, in this study, TEOS (Tetraethyl orthosilicate) sol-gel reaction was introduced into APTES based QDs to coat the QDs with denser SiO2 to isolate air and moisture, thus effectively improving the stability of the films. Finally, in order to enhance the uniformity of light emission, we doped SiO2 nanospheres to increase the Mie scattering. The results show that the PLQY of the films increases with the increase of the doping amount. The red light films with PLQY up to 45% and lasting for one month, which are expected to be used in WLED and display backlights in the future.

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