鈣鈦礦白光發光二極體

Perovskite White Light Emitting Diodes

張哲瑀(Che-Yu Chang)

指導教授 ： 許經夌 ； 趙宇強

中原大學/理學院/物理學系/博士(2022年)

https://doi.org/10.6840/cycu202201333

摘要

本論文旨在通過溶液法製備單一發光層的鈣鈦礦白色發光二極體，形成二元和三元混合單層發光層。在鈣鈦礦發光二極體中很少討論單層發光的研究，多數在討論材料穩定性、毒性以及提升發光二極體之效率。採用溶液製程製備單層發光層以利於降低成本使鈣鈦礦白光發光二極體走向量產。
在第3章中，透過測試鈣鈦礦前驅液中的橙色至紅色有機材料的溶解度時，鈣鈦礦前驅溶液對摻雜物的溶解度的限制導致了製造過程的困難。通過混合天藍色鈣鈦礦材料和橙色近紅外 (NIR) 有機化合物 1 (N(Ph-T-DCV-Ph)3, SA343) 和 2 (TPA-T-DCV-Ph, SA321) 以實現白光。光致發光螢光光譜、X光繞射分析、掃描電子顯微鏡和共軛焦光激發掃描螢光顯微鏡之量測研究鈣鈦礦薄膜參雜橙色-NIR發射的化合物之薄膜特性與影響。鈣鈦礦白光 LED 在 11 V 時的 CIE 色度坐標為 (0.3, 0.49)，接近理想的純白光的CIE色度坐標 (0.33, 0.33)。

在第4章中，採用天藍色MAPb(Br0.6Cl0.4)3和橙紅色Rhodamine 6G的混合物作為單一發光層並應用在鈣鈦礦白色發光二極體上。 通過穩態吸收、穩定性、時間解析光致發光光譜儀、X光繞射分析、掃描電子顯微鏡和共軛焦光激發螢光顯微鏡研究了Rhodamine 6G對鈣鈦礦薄膜特性影響。由 MAPb(Br0.6Cl0.4)3 和Rhodamine 6G 構成的鈣鈦礦發光二極體，發射混合以產生白光。 對於具有 2 wt% 和 3 wt% Rhodamine 6G 參雜的鈣鈦礦元件，分別在 9 V 和 10 V 的外加偏壓下獲得了 (0.33, 0.4) 和 (0.36, 0.40) 的 CIE 色度坐標。

在第 5 章中，通過調整各種直徑（~3.8 nm、~4.4 nm、~6.1 nm、~13.1 nm) 的量子點接近玻爾激子半徑附近。穩態吸收光譜、光致發光螢光光譜、X光繞射分析 和時間解析光致發光光譜儀用於量測量子侷限的 CsPbBr3 量子點之特性。由藍色和綠色 CsPbBr3 量子點組成的二元混合溶液和複合薄膜顯示出兩個發射峰，沒有陰離子交換問題。將紅色CdSe量子點溶液加入到天藍色二元混合溶液中，形成具有白色放光的三元混合溶液。觀察到三個清晰的發射峰，並獲得了 CIE 色度坐標（0.33, 0.31）。製備了具有白色發射的 QD 聚合物複合膜並將其堆疊在 UV LED 上，以展示全轉換白色 LED。該三元混合溶液還用於製備量子點發光二極體的發光層，展示了三個發光峰和（0.34，0.33）的CIE色度坐標。

關鍵字

鈣鈦礦發光二極體 ； 白光

並列摘要

The thesis aims to fabricate a single emissive layer for perovskite white light-emitting diodes through solution process to form the binary and ternary mixture single emissive layer. The topic of a monolayer for emission is seldom discussed in perovskite light-emitting diode. The solution process and a single emissive layer are utilized to lower the cost and toward the mass production.
When testing the solubility of orange to red organic materials doped into the perovskite precursor solution, the limitation of solubility of perovskite precursor solution for dopants is led to the potential of fabricating procedure. The perovskite white light-emitting diodes with single emissive layer by mixing the emissions from a sky-blue perovskite material and an orange-near infrared (NIR) organic compound 1 (N(Ph-T-DCV-Ph)3, SA343) and 2 (TPA-T-DCV-Ph, SA321) were investigated in chapter 3. Compounds with orange-NIR emission are synthesized and the influence of the compounds on the perovskite films are investigated by absorption and photoluminescence spectroscopy, X-ray diffraction, scanning electron microscopy and confocal laser-scanning fluorescence microscopy. The perovskite white LEDs were realized with CIE chromaticity coordinates of (0.3, 0.49) at 11 V, which is approaching to the ideal pure white emission coordinates (0.33, 0.33).
In chapter 4, Perovskite white light-emitting diodes were realized by using a mixture of sky-blue MAPb(Br0.6Cl0.4)3 and orange-red Rhodamine 6G as the single emissive layer. The influences of Rhodamine 6G on the properties of perovskite films are investigated by steady-state absorption, steady-state and time-resolved photoluminescence spectroscopy, X-ray diffraction, scanning electron microscopy and confocal laser-scanning fluorescence microscopy. The perovskite light-emitting diode emissions from MAPb(Br0.6Cl0.4)3 and Rhodamine 6G were blended to generate white light. CIE chromaticity coordinates of (0.33, 0.4) and (0.36, 0.40) were obtained for the device with 2 wt% and 3 wt% Rhodamine 6G, at applied potential 9 V, and 10 V, respectively.
In chapter 5, CsPbBr3 perovskite quantum dots (QDs) with various emission wavelengths, 462 nm, 475 nm, 495 nm, and 519 nm were prepared by tuning the various diameter (~3.8 nm, ~4.4 nm, ~6.1 nm, and~13.1 nm) of QDs around Bohr exciton radius. Absorption, PL, XRD, and time-resolved PL were used to characterize quantum-confined CsPbBr3 QDs. The binary mixture solutions and composite films composed of blue and green CsPbBr3 quantum dots showed two emission peaks without anion exchange issue. Red CdSe quantum dot solution was added into the sky-blue binary mixture solution to form a ternary mixture solution with white emission. Three clear emission peaks were observed and the CIE chromaticity coordinates (0.33, 0.31) were obtained. A QD-polymer composite film with white emission was prepared and stacked on an UV LED to demonstrate full conversion white LEDs. The ternary mixture solution (QD-462, QD-514, and CdSe-633 ) was also used to prepare the emissive layer of quantum dot light-emitting diodes to demonstrate three emission peaks and CIE coordinates of (0.34, 0.33).

並列關鍵字

Perovskite ； white light-emitting diode

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