표제지
국문초록
목차
1. 서론 11
2. 이론적 배경 14
2.1. 양자점(Quantum dots) 14
2.2. Microemulsion 16
2.2.1. 마이크로에멀젼의 정의 16
2.2.2. 마이크로에멀젼의 구조 및 특징 17
2.2.3. Reverse micelle을 이용한 나노 입자 생성 21
2.2.4. Reverse micelle의 크기 조절 25
3. 실험 장치 및 방법 27
3.1. 실험 시약 및 기기 27
3.1.1. 실험 시약 및 기구 27
3.1.2. 분석 방법과 기기 28
3.1.2.1. 여기와 방출 28
3.1.2.2. 입자 이미지 및 성분 분석 29
3.2. 실험 순서 및 방법 30
3.2.1. 실리카에 담지된 ZnSe nanocrystal 제조 30
3.2.2. ZnSe QDs의 layer 형성 32
4. 결과 및 고찰 35
4.1. Transmission electron microscopy (TEM) 이미지 분석 35
4.2. UV-Vis spectrophotometer를 이용한 흡광도 측정 38
4.3. XRD(X-Ray Diffractometer)에 의한 성분 분석 40
4.4. PL(Photoluminescence spectrophotometer) 측정 42
4.4.1. ZnSe NCs와 실리카에 담지 된 ZnSe NCs의 PL 분석 43
4.4.2. 실리카에 담지 된 ZnSe 양자점의 W에 따른 PL 분석 45
4.4.3. 실리카에 담지 된 ZnSe 양자점의 시간에 따른 PL 분석 48
4.5. FIB (Focus ion beam) 분석 50
4.6. 고체 layer 상에서 QDs의 PL 분석 52
5. 결론 55
6. 참고문헌 56
ABSTRACT 59
Table 1. Average sizes of ZnSe nanocrystals measured at different oil phase and W value 47
Figure 1. Microemulsion Structure. 18
Figure 2. Structure of microemulsions 19
Figure 3. Phase inversion of emulsions. 20
Figure 4. Conceptual illustration of reverse micelle system. 23
Figure 5. Intermicellar exchange process of reverse micelle system. 24
Figure 6. Schematic of microemulsion technique for ZnSe quantum dots synthesis. 33
Figure 7. Preparation of silica-encapsulated ZnSe nanocrystals by mixing two water-in-oil microemulsions. 34
Figure 8. TEM images of silica-encapsulated ZnSe quantum dots prepared by AOT reverse micellar solution. 37
Figure 9. UV-Vis absorption spectra of silica-encapsulated ZnSe NCs in water/AOT/oil microemulsions. 39
Figure 10. X-Ray diffraction traces for silica-encapsulated ZnSe nanocrystals and result for cubic NCs simulation. 41
Figure 11. PL spectra of ZnSe quantum dots (a) and silica-encapsulated quantum dots (b) in AOT/water/Cyclohexane reversed micellar solutions. 44
Figure 12. PL spectra of silica-encapsulated quantum dots in AOT/water/Cy clohexane reversed micellar solutions. 46
Figure 13. PL spectra of silica-encapsulated quantum dots ([H2O]/[AOT]=3) in AOT/water/Cyclohexane reversed micellar solutions as a function of time 49
Figure 14. FIB image of thin layers on gold surface after removal of surfactant and solvent 51
Figure 15. PL spectrum of thin layer of ZnSe on gold surface after removing solvent and surfactant 53
Figure 16. PL spectrum of thin layer of silica-encapsulated ZnSe QDs on gold surface after removing solvent and surfactant 54