鈣鈦礦發光二極體為新一代應用於高解析度、高亮度及廣色域顯示器的有利候選者。然而位於650奈米紅光波段的鈣鈦礦發光二極體因發光層材料穩定性不佳及操作壽命短等問題，目前仍在開發階段。在本研究中，主要在於合成具有高螢光量子產率且調控發光波長於650 奈米的鈣鈦礦奈米材料，並將其應用於發光二極體的製作。在此，利用熱注入法與過量碘源的添加合成出鉛碘鈣鈦礦量子點，使其發光波長由690奈米藍位移至650奈米。接著，再藉由碘化鉀的優化處理，可使銫鉛碘鈣鈦礦量子點的螢光量子產率提高至83.5％，並大幅改善其穩定性。而透過苯乙基碘化銨與聚甲基丙烯酸甲酯進行銫鉛碘鈣鈦礦發光層與電子/電洞傳輸層的界面修飾，可使所製備的發光二極體的最佳外部量子效率值達到8.12%，最大輝度達到345 cd/m2，發光波長位於652奈米，並具有良好的操作穩定性和壽命。由以上研究結果顯示，通過合適的鈣鈦礦量子點合成方式與優化處理，搭配界面優化策略，能有效提升紅光鈣鈦礦量子點發光二極體的光電效能。

Perovskite light-emitting diodes (PeLEDs) are promising candidates for high-resolution, high-brightness, and wide color gamut displays. However, red-emitting PeLEDs in the wavelength of 650 nm are still in the developmental stage due to poor stability of the emissive layer material and short operational lifetime. In this study, the focus was on fabricating red-emitting perovskite nanomaterials with high fluorescence quantum yield and an emission wavelength at 650 nm, and applying them in light-emitting diodes (LEDs). Through a hot-injection method and the addition of excess iodine source, all-inorganic cesium lead iodide (CsPbI3) perovskite quantum dots (PQDs) were synthesized, shifting their emission wavelength from 690 nm to 650 nm. Subsequently, by optimizing the post-treatment with potassium iodide, the fluorescence quantum yield of CsPbI3 PQDs was increased to achieve 83.5% while significantly improving their stability. Furthermore, by modifying the interface between the CsPbI3 emissive layer and the electron/hole transport layer with phenethylammonium iodide (PEAI) and poly(methyl methacrylate) (PMMA), the optimized external quantum efficiency (EQE) of the light-emitting diodes achieved 8.12%. The devices exhibited a maximum brightness of 345 cd/m², an emission wavelength at 652 nm, and demonstrated good operational stability and lifetime. These results demonstrate that by employing appropriate PQDs synthesis methods and optimization treatments, along with interface engineering strategies, the optoelectronic performance of red-emitting perovskite LEDs can be effectively enhanced.

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