量子點和鈣鈦礦二維材料之特性與應用
No Thumbnail Available
Date
2021
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
本論文共分三個部分：1.鈣鈦礦量子點-PCL(polycaprolactone)複合材料;2.CdSe量子點發光二極體的電洞注入層及電洞傳輸層之參雜;3.PbBr2及醋酸鉛二維晶體之研究。第一部分，我們合成CsPbBr3鈣鈦礦量子點，因為量子點具有量子侷限效應，所以我們藉由調控量子點粒徑大小得到460nm,到515nm光波長的CsPbBr3鈣鈦量子點。由於鈣鈦礦量子點在大氣下不易儲存，因此將量子點與高分子材料PCL混合，做出複合材料，研究結果顯示，由於我們用高分子材料包覆量子點，讓鈣鈦礦量子點在大氣環境下，能夠保存更久的時間。第二部分，我們使用全溶液製程製作CdSe的量子點發光二極體。在電洞注入層poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS)參雜不同比例的P105分散劑，找到PEDOT:PSS參雜的最佳條件後，接著電洞傳輸層poly(9-vinylcarbazole)(PVK)參雜1,1-Bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC)接著加上Bis[3,5-di(9H-carbazol-9-yl)phenyl]diphenylsilane (SimCP2)，依序對這一系列參雜不同比例，觀察對發光二極體元件的影響。電洞注入層最佳參雜比例使表面粗糙度從3.1853nm下降到2.0144nm，而元件的量子效率也從2.23%達到3.33%，結果表明適當得參雜可以有效的改善元件載子的注入能力。最後，我將PbBr2及醋酸鉛在二氧化矽的基板上生長二維材料晶體，並改善製程，使得我可以得到較大或較薄的晶體，其中，醋酸鉛晶體可以長到約6um的六角形晶體，我使用AFM觀察其厚度，最薄到達20nm。接著，我使用其他材料(MABr、MAI)個別與兩種晶體反應，使我最後能得到鈣鈦礦的薄片晶體。
Three materials were investigated in this research work: 1. perovskite nanocrystal−PCL composites; 2. organic materials for doping hole transporting layer; 3. PbBr2 and lead(II) acetate flakes.In the first part, CsPbBr3 perovskite nanocrystals were synthesized with various emission wavelength from 460 to 515 nm by controlling the diameter of the nanocrystals. To strengthen the air stability of the nanocrystals, polycaprolactone (PCL) was dissolved and blended with nanocrystals for the fabrication of perovskite nanocrystal-PCL composites. We demonstrated that the perovskite nanocrystal-PCL composites exhibited good air barrier property.In the second pert, the influence of the doping of hole transport material on the performance of quantum dots light-emitting diodes (QD-LEDs) was investigated. Commercial available P105 was blended with PEDOT:PSS. The surface roughness of PEDOT:PSS was decreased from 3.1853nm to 2.0144nm after molecule doping. 1,1-Bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC) and Bis[3,5-di(9H-carbazol-9-yl)phenyl]diphenylsilane (SimCP2) were doped into poly(n-vinylcarbazole) (PVK). Device performance could be enhanced once the doping ratio was optimized. The external quantum efficiency of QD-LEDs was increased from 2.23% to 3.33%. These results showed that hole injection can be improved via molecule doping.Finally, PbBr2 and lead(II) acetate flakes were prepared on Si/SiO2 substrates. Experimental conditions were controlled to get flakes with large area or thin thickness. The diameter and thickness of the flakes of ~6 um and 20 nm were obtained, respectively. By reacting flakes with methylammonium iodide or methylammonium bromide, perovskite flakes were obtained.
Three materials were investigated in this research work: 1. perovskite nanocrystal−PCL composites; 2. organic materials for doping hole transporting layer; 3. PbBr2 and lead(II) acetate flakes.In the first part, CsPbBr3 perovskite nanocrystals were synthesized with various emission wavelength from 460 to 515 nm by controlling the diameter of the nanocrystals. To strengthen the air stability of the nanocrystals, polycaprolactone (PCL) was dissolved and blended with nanocrystals for the fabrication of perovskite nanocrystal-PCL composites. We demonstrated that the perovskite nanocrystal-PCL composites exhibited good air barrier property.In the second pert, the influence of the doping of hole transport material on the performance of quantum dots light-emitting diodes (QD-LEDs) was investigated. Commercial available P105 was blended with PEDOT:PSS. The surface roughness of PEDOT:PSS was decreased from 3.1853nm to 2.0144nm after molecule doping. 1,1-Bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC) and Bis[3,5-di(9H-carbazol-9-yl)phenyl]diphenylsilane (SimCP2) were doped into poly(n-vinylcarbazole) (PVK). Device performance could be enhanced once the doping ratio was optimized. The external quantum efficiency of QD-LEDs was increased from 2.23% to 3.33%. These results showed that hole injection can be improved via molecule doping.Finally, PbBr2 and lead(II) acetate flakes were prepared on Si/SiO2 substrates. Experimental conditions were controlled to get flakes with large area or thin thickness. The diameter and thickness of the flakes of ~6 um and 20 nm were obtained, respectively. By reacting flakes with methylammonium iodide or methylammonium bromide, perovskite flakes were obtained.
Description
Keywords
量子點, 鈣鈦礦, Quantum Dots, Perovskite