Synthesis of Perovskite Nanocrystal Using Liquid Crystal and Application to Optoelectronic Device

Abstract

This dissertation investigates the innovative utilization of liquid crystals in the synthesis of perovskite nanocrystals, exploring their potential to enhance the control of nanocrystal morphology, stability, and the optoelectronic properties. This research is motivated by the need for precise morphological control and enhanced stability in perovskite nanocrystals, which are critical for advancing their application in optoelectronic devices. The primary objective of this study is to elucidate the uniform synthesis and growth mechanisms of rod-shaped perovskite nanocrystals using liquid crystals as a template and to assess their impact on the optical properties of nanocrystals post-ligand exchange processes. Liquid crystals offer a strategic approach due to their elasticity and orientation, acting as templates during the synthesis of nanocrystals. This allows for the uniform synthesis of nanocrystals with targeted morphologies. The presence of liquid crystals during the synthesis process enables advanced analytical and quantitative analysis through their optical polarization phenomena. The methodology adopted involves the liquid crystal-assisted synthesis of perovskite nanocrystals, focusing on rod-shaped morphologies. Utilizing liquid crystals as a template not only aids in achieving the desired morphology, but also improves the stability of nanocrystals during ligand exchange processes. This research introduces a novel chemical transformation approach using liquid crystal templates to develop precise synthesis methodologies. The influence of liquid crystals on the surface of nanocrystals during post-ligand exchange processes is critically evaluated to understand their impact on optical and optoelectronic properties of the nanocrystals. The final chapters discuss the successful synthesis of bismuth-based perovskite nanocrystals using the liquid crystal method and a machine learning optimization approach to overcome the lead toxicity challenge. These techniques enhance predictive modeling for achieving desired outcomes and developing lead-free perovskite nanocrystals. This research contributes to the field of materials science by offering viable solutions for the commercialization of perovskite nanocrystals in optoelectronic applications and highlights innovative methods to address environmental and stability concerns associated with these materials.