Kinetic data-driven development of light-interacting materials

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Over the past 5 years, lead halide perovskite (LHP) nanocrystals (NCs) have observed extended use in a multitude of optoelectronic applications due to their outstanding properties of which defect tolerance out competes traditionally applied chalcogenides NCs (e.g., CuInS2). Whilst significant attention has been drawn to their device performance, little recognition is paid towards their synthesis. Typically, NCs are synthesised using a batchwise hot injection protocol by which a precursor is swiftly introduced into the mother solution, containing appropriate ligands, to trigger nucleation and growth which takes place at millisecond timescales. Albeit a facile method, as-synthesised NCs suffer from dispersity in size and morphology due to the velocity at which the reaction proceeds in convolution with the time required to achieve uniform precursor concentration following injection. As a result, absence of understanding during earlier times in crystallisation renders poor control over as synthesised NCs thus detrimental optoelectronic performance. During this PhD, we attempt to probe early crystallisation kinetics of LHP and perovskite inspired materials to assess their intrinsic kinetics in governing the evolution of size and morphology. In tandem, we couple this with transient photophysical measurements to gain an understanding of defect formation during growth. Overall, we attempt to assess the interconnected relationship of synthesis, structure, and properties of confined perovskite NCs paving the way for controlled synthesis in wider optoelectronic applications.