Integrating Broadband Emission and Luminescence Switching in Zero-Dimensional Organic-Inorganic Metal Halides

Ray, Bishes (2025) Integrating Broadband Emission and Luminescence Switching in Zero-Dimensional Organic-Inorganic Metal Halides. Masters thesis, Indian Institute of Science Education and Research Kolkata.

Text (MS Dissertation of Bishes Ray (20MS203)) 20MS203_Thesis_file.pdf - Submitted Version Restricted to Repository staff only Download (2MB)

Abstract

Phase transition dynamics are a major concern in the many applications of organic inorganic metal halides, as they essentially govern the optoelectronic characteristics and stability of perovskite materials and devices. This work presents the synthesis and characterization of luminescent biphosphonium bromide salts and their derived copper-based organic–inorganic metal halides. The organic salts, synthesized from tertiary bisphosphanes, exhibit blue prompt fluorescence in solution and green phosphorescence in the solid state due to anion–π interactions. Incorporation of these cations into a copper halide framework produces a zero-dimensional metal halide with confined [Cu₂Br₄]²⁻ polyhedra, leading to a self-trapped exciton state that, together with the cation emissions, yields near-white light emission. Structural analysis reveals a phase transition from a kinetically unstable white state to a thermodynamically stable black state via polyhedral switching and copper oxidation, which decreases the direct band gap and enhances charge-carrier mobility. These findings provide a strategic framework for tuning photophysical properties in luminescent metal halide systems with promising applications in advanced optoelectronic devices.

Actions (login required)

View Item