利用六甲基二矽硫烷幫助CsPbI3鈣鈦礦奈米立方晶相穩定之研究

鈣鈦礦奈米晶體因其在可見光的高吸收係數、雙極性、直接能隙等光學性質，在太陽能電池與發光二極體上都有良好的應用，所以成為備受矚目的發光材料之一，但因為其在大氣下的低穩定性，造成其實際應用上的困難。而此篇研究主要針對此材料的穩定性做探討，此類材料在大氣下因水氧的侵入使其晶體崩解，然而其本身的高光學活性晶相在室溫下，也會自發的轉換成非光學活性的晶相，使其喪失應用的價值。而本實驗利用配體的置換，將原本以油酸為主要配體的鈣鈦礦奈米晶體，置換成小分子的六甲基二矽硫烷，改善了其在大氣下的穩定度，可以從可見光吸收光譜、X光繞射光譜、穿透式電子顯微鏡、螢光放光光譜等，發現到以六甲基二矽硫烷為配體的鈣鈦礦奈米晶體其光學性質維持的時間都較以油酸為配體的鈣鈦礦奈米晶體長，表示此法增強了鈣鈦礦奈米晶體在大氣下具光學活性之立方晶相的穩定性，以利後續之應用

關鍵字

鈣鈦礦奈米晶體；立方晶相；六甲基二矽硫烷

並列摘要

Perovskite nanocrystals have a good application in solar cells and light-emitting diodes because of their optical properties such as high absorption coefficient, bipolar, direct energy gap and so on, so they become one of the most popular luminescent materials , But because of its low stability in the atmosphere, resulting in its practical application of the difficulties. This study is mainly for the stability of this material. This kind of material in the atmosphere due to the intrusion of water and oxygen to its crystal disintegration, but its own high optical activity crystal phase at room temperature also, will spontaneous conversion Non-optically active crystal phase, so that it lost the value of application. In this study, the use of ligand replacement, the original oleic acid as the main ligand of the perovskite nanocrystals, replaced by small molecules of hexamethyldisilane, improved its stability in the atmosphere, from Visible light absorption spectroscopy, X-ray diffraction spectroscopy, transmission electron microscopy, fluorescence emission spectroscopy, etc. The observed optical properties of perovskite nanocrystals with hexamethyldisilane as ligand Which is more stable than the perovskite nanocrystals with oleic acid as ligand, which indicates that this method enhances the stability of the optically active cubic crystal phase of perovskite nanocrystals in the atmosphere to optimize its application.