本論文利用溶劑過飽和法，能夠於大氣環境中簡單、快速的合成出具高發光效率的全無機銫鉛溴鈣鈦礦量子點；並使用3-氨基丙基三乙氧基矽烷(APTES)作為配體，取代有機長碳鏈分子，改善做成元件後，有機長碳鏈分子會殘留於表面以及影響元件特性的問題，並利用APTES本身有機矽烷的特性，在鈣鈦礦量子點外形成二氧化矽保護層，有效阻止量子點受環境因素影響。
本研究透過嘗試不同的鉛與APTES莫耳比尋找最好的發光效率，我們發現在鉛與APTES莫耳比為1:1.5時會有最佳的光激量子效率(Photoluminescence quantum yield, PLQY)為58%。此外利用有機矽烷本身的特性，搭配實驗室自行合成之二氧化矽奈米球，使受二氧化矽包覆的鈣鈦礦量子點附著於奈米球上，透過奈米球的光學特性形成擴散粒子(Diffractive particles, DP)，提高量子點接收激發光子的機率。以量子點與奈米球重量比為1:2.17所形成的擴散粒子最高發光效率可達81%，最終並以此擴散粒子搭配聚甲基丙烯酸甲酯(PMMA)所形成的發光擴散薄膜(Perovskite quantum dots diffusion film, PQDF)發光效率為65%。
自行合成的發光擴散薄膜具有良好的發光效率以及發光特性，且薄膜具有良好的可塑性可應用於多種元件上，利用此方法所做成之薄膜具有成為下一代彩色濾光片的有利候選人。

In this paper, we use solvent supersaturation method in atmosphere to synthesize a fully inorganic perovskite quantum dot with high luminosity; and use APTES as a ligand to replace the organic long chain molecule. By replacing the ligand, we can prevent organic long chain molecules remain on the surface of device and can improve the characteristics of the device. Due to using APTES as ligand to synthesize perovskite quantum dots, we can coat silica on the surface of quantum dot as protection layer by utilize the characteristics of APTES. The protective layer can effectively prevent the quantum dots from being affected by environmental issues.
In this study, we tried to find the best PLQY by trying different Pb and APTES molar ratios. We found that when the Pb and APTES molar ratio is 1:1.5, there will have the best result of PLQY 58%. In addition, by utilizing the characteristics of organic silane, we can combine quantum dot and silica nanospheres together. The silica-coated perovskite quantum dots can attach to the surface of nanospheres. Due to the optical properties of the nanospheres, we can cause UV-light scattered and increase the opportunity for quantum dots on the sphere surface to absorb photons. We add different weights of nanospheres into the solvent which contain quantum dots to find the best result. When quantum dots and nano sphere have weight ratio at 1:2.17 can form diffractive particles(DP) with high PLQY 81%. Greatly improve the luminous efficiency of quantum dots.
The self-synthesized diffractive particles can be combined with polymethyl methacrylate(PMMA) to make perovskite quantum dots diffusion film. The film made by this method may be a potential candidate of next generation color filter.

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