무기 광감응제의 내부 구성요소 상호작용의 동역학적 고찰

다국어 초록 (Multilingual Abstract)

Due to the excellent photophysical properties of perovskite quantum dots, their introduction into solar driven chemistry and optoelectronic devices has been taken up as an attractive alternative. Despite the outstanding photophysical properties and successful application to photovoltaic devices, applied electrical field induced phenomena could induce various component change and time dependent variations in the perovskite quantum dots. In this study, CsPbX3 (X = Cl-, Br-, and I-) PQDs were self-assembled with PbSO4-oleate to form a peapod-like morphology to selectively control halide ion exchange and investigated the behavior of X-site halide and A-site cation exchange processes in between the perovskite quantum dots. Considering the distinct absorption and bright luminescence characteristics of these PQDs, in situ UV-Vis. absorption and fluorescence spectroscopies were employed to monitor the time-dependent band gap and compositional changes of the PQDs. First, determined that the halide exchange in the capped PQDs is hindered—unlike the rapid anion exchange in noncapped PQDs—by a reduction in the halide exchange kinetic rate depending on the extent of coverage of the PQDs. Thus, we tracked the halide ion exchange kinetics between CsPbBr3 and CsPbI3 PQDs, depending on the coverage, using in situ UV-Vis. absorption/photoluminescence spectroscopy. We regulated the halide exchange reaction rate by varying the capping reaction temperature of the PQDs. The capping hindered the halide exchange kinetics and increased the activation energy. Next, through in situ photoluminescence spectroscopy under the applied bias, we figured out the role of applied bias and current to the exchange process. Through these studies, we were able to track the enhanced migration rate of ions in the batch solution could facilitate the ion interdot exchange reaction dynamics in between the perovskite quantum dots. This study can be used to develop the practical strategy to apply the perovskite quantum dots to solar driven chemistry and optoelectronic devices.

목차 (Table of Contents)

• 1. 서 론 1
• 1.1. 연구배경 1
• 2. 실 험 6
• 2.1. CsPbX3(X = Br 또는 I) 양자점의 합성 및 정제 6
• 2.2. PbSO4-올레이트 캐핑된 CsPbX3 양자점의 합성 7
• 2.3. FAPbX3 (X: I–, Br–) 양자점의 합성 및 정제 8
• 2.4. 이온교환 반응을 위한 양자점 용액의 준비 10
• 2.5. 실험장치 및 실험 방법 10
• 3. 결 과 12
• 3.1. PbSO4-올레이트 캡핑이 양자점의 특성에 미치는 영향 12
• 3.2. 두 양자점 사이의 이온 교환 반응에 대한 캡핑의 효과 19
• 3.3. 다양한 양자점의 재료 특성 및 흡수/방출 특성 34
• 3.4. 전압을 가한 후 다양한 이온교환 추적 39
• 4. 결 론 51
• 참고문헌 53
• 영문요약 57