鈣鈦礦量子點相較於一般傳統量子點具有較窄的放射峰半高寬、較高量子轉換效率高與放射光波長的易調變性等優秀的光電性質且不含鎘，其可應用於太陽能電池、發光二極體及顯示器面板等光電元件，故近年來受到極大的關注。然而其穩定性在大氣、高溫與連續紫外光照射的條件下並不佳，故增強鈣鈦礦量子點之穩定性使其具備商業應用性已成為在相關領域中最重要的議題。本研究利用硫酸化之奈米纖維素晶體取代傳統以油酸及油胺作為表面配體與鈣鈦礦量子點合成複合螢光膜，並成功製造出無機鈣鈦礦量子點複合螢光膜與有機無機混合鈣鈦礦量子點複合螢光膜共三種不同組成之複合螢光膜，更進一步利用陰離子混合達到放射波長可調變性（藍光到綠光）。經穩定性測試，由於奈米纖維素晶體的輔助，鈣鈦礦量子點複合螢光膜之穩定性比一般傳統鈣鈦礦量子點上升數倍。綜合以上優點，本研究提出之鈣鈦礦量子點複合螢光膜為光電領域及相關應用元件提供了嶄新的可能性。

Perovskite quantum dots (PQD) have attracted much attention for developing cadmium-free quantum light emitting displays (QLED), solar cells and light emitting diodes (LED) based on outstanding light emission properties including narrow full width at half maximum (FWHM), tunable bandgap, and ultra-high (>90%) photoluminescence quantum yield (PLQY). Nevertheless, the poor stability under ambient condition, high temperature, and continuous light irradiation is the main problem for practical applications. In recent years, enhancing the stability of PQD to meet the requirement for commercialize application is the most important issue in the related research fields. In this study, a new method has been proposed to effectively stabilize PQD by synthesizing it with sulfate-functionalized cellulose nanocrystals (CNC) at room temperature without using traditional PQD capping ligands such as oleylamine (OAm) and oleic acid (OA). We have successfully synthesized inorganic and organic-inorganic PQD/CNC hybrid luminescent films. In addition, color-tunability (blue to green emission color) has been achieved by tuning the anion concentration. Under the stability test, the PQD/CNC hybrid luminescent films are more stable than traditional PQD. Therefore, the PQD/CNC hybrid luminescent films can provide new possibility for practical applications in the future development of PQD related devices.

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