Compositionally engineered ternary PbSxSe1-x quantum dots active in short-wavelength infrared region

다국어 초록 (Multilingual Abstract)

Quantum Dots (QDs) have unique optical properties due to their inherent exciton Bohr Radius, enabling versatile bandgap tuning from ultraviolet to visible and infrared regions. This versatility positions them as promising candidates for optoelectronic devices such as displays, photodetectors, and solar cells. In particular, shortwave infrared (SWIR) applications, crucial for fields like optical communication and imaging, face cost challenges with traditional III-V materials. Colloidal QDs, especially lead chalcogenide- based QDs like PbS and PbSe, offer a cost-effective alternative. While PbS QDs is known for higher power conversion efficiency in solar cells, PbSe QDs theoretically possesses superior charge transport properties, but challenges such as low chemical yield and stability exist. To address these issues, we propose PbSxSe1-x ternary QDs.
Previous studies have explored PbSxSe1-x QDs, with improvements in solar cells. However, existing syntheses exhibit bandgap variations with composition changes. Our research focused on synthesizing PbSxSe1-x QDs active in the SWIR region, achieving uniformity and compositional control confirmed by XRD, XPS, ICP-OES, and TEM analyses. Additionally, we investigated the role of diphenylphosphine (DPP) in PbSxSe1-x QDs synthesis through 31P NMR measurement. The synthesized PbSxSe1-x QDs demonstrate enhanced air-stability and chemical yield compared to PbSe QDs. Moreover, the development of PbSxSe1-x ink opens avenues for diverse applications. This study will contribute to the advancement of SWIR photodetectors, offering a more economical alternative to traditional materials.

목차 (Table of Contents)

• Table of Contents i
• List of Figures ii
• Abstract iv
• 1. Introduction 1
• 2. Materials and methods 3
• 3. Results and Discussion 6
• 4. Conclusion 20
• 5. Reference 21
• 6. 국문요약 24