由於全無機鈣鈦礦量子點擁有純粹的放光特性以及全可見光的光調變性，因此適合作為開發無鎘的量子點發光二極體元件的材料。然而，鈣鈦礦量子點還是受到穩定性的影響而限制其應用範圍。本研究利用含有較強束縛能的硫酸根奈米纖維素晶體來取代傳統的油酸及油胺配體，合成出紅、綠、藍三種螢光增強複合膜。為了進一步加強紅色螢光膜的穩定性，本研究在CsPbI3量子點中摻雜鋅離子，結果顯示經過摻雜後的紅色螢光複合膜在大氣環境中經過33天後還能保有93%的螢光強度，而未摻雜鋅離子的螢光複合膜及有摻雜鋅離子的傳統膠體溶液經過一個小時後僅剩下50%左右的螢光強度。綜合以上所述，鈣鈦礦量子點螢光複合膜擁有高穩定性、放光波長窄、全色域等的特點，為下個世代低成本、低耗能的鈣鈦礦量子點光電元件提供了新的可能性。

All-inorganic perovskite quantum dots (PQDs) have held significant promise for developing cadmium-free light-emitting devices due to their outstanding color purity and tunable bandgap throughout the visible spectrum. However, they are still limited in practical applications due to stability issues. Herein, a strategy is developed to replace traditional ligands such as oleylamine and oleic acid for improving the binding state between exposed Pb ions and ligands by sulfate-functionalized cellulose nanocrystals (CNCs) to synthesize red, green, and blue-emitting PQD/CNC light enhancement films. To further increase the stability of red-emitting films, Zn metal ions were introduced in the B-cation site of CsPbI3. It has been noticed that the relative photoluminescence emission intensity of the Zn-alloyed CsPbI3 PQD/CNC film can be maintained at 93% under the ambient condition for 33 days, whereas that of both the un-alloyed film and colloidal Zn-alloyed CsPbI3 dropped to ~50% after 1 hour. Thus, the developed PQD/CNC enhancement films can provide a new possibility for highly-stable and full-color applications in the next-generation low-cost, low power consumption, and efficient PQD based optoelectronic devices.

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