Self-Assembled Coordination Architectures for Fluorescence Modulation, Photocatalysis, and Light Harvesting

Abstract

Self-assembly and noncovalent interactions play a pivotal role in the design of complex, and intricate functional structures. Among several design approaches, metal-ligand coordinationdriven self-assembly has emerged as one of the most efficient methodology for constructing complex 2D and 3D architectures. This approach is favored due to its relatively simple design principle, predictable directionality, and high bond enthalpy. Over the years, a vast range of topologically intricate structures was designed using this approach. However, reports on the construction of complex 2D, and 3D architectures using highly symmetric and rigid square planner Pd(II)/Pt(II)-based metal acceptor in combination with rigid polypyridyl donor building blocks dominate the literature so far. In this context, imidazole-based donors and flexible donors remained less explored than conventional pyridyl donors. It is envisioned that the use of imidazole-based donors as well as flexible donors might provide interesting results in terms of the structure of the final assembly. The rotational degree of freedom in these cases can offer different bite angles to the rigid pyridyl donor and may affect the structure of the final assembly. On the other hand, supramolecular coordination polymers (SCPs) that are made up of an ordered arrangement of repeating monomeric units have gained significant attention as they offer high surface area, ordered porosity, and better stability compared to discrete supramolecular coordination complexes. The objective of the thesis is to synthesize various functional supramolecular architectures (both discrete and coordination polymers) using imidazole-based donors and flexible donors via the metal-ligand coordination approach. And to explore these self-assembled architectures for fluorescence modulation, visible-light-driven photocatalysis, and light harvesting.