Supramolecular assemblies involving thermally activated delayed fluorescence emitters

Supervisor: Prof Eli Zysman-Colman (St Andrews)

My group has dual interests in the study of thermally activated delayed fluorescence (TADF) emitters, which we primarily use in OLEDs, and in the supramolecular assembly of photoactive materials, particularly as the strategy can be used for to generate supramolecular photocatalysts and improved emission for solid-state lighting. We recently published the first example of a coordination cage formed of a TADF emitter and Pd(II) ions ACS Appl. Energy Mater., 2018, 1, 2971−2978. Though the cage was luminescent the design was suboptimal as non-radiative decay channels dominated and the photoluminescence quantum yield was poor. This project explores the synthesis of second generation TADF emitters bearing distal 4-pyridyl groups. In modifying the original design and strengthening both the donor and the acceptor units it is envisaged that upon self-assembly the cage will remain TADF, which is the desired goal. The project consists of TADF emitter synthesis and supramolecular assembly with Pd(II) salts in the first instance. The project will be expanded towards the study of the first examples of covalent organic frameworks (COFs) incorporating TADF emitters. Here, the TADF emitter will be decorated with pendant aldehyde groups, which will then be condensed with diamines to form extended COF systems. Detailed photophysical and electrochemical characterization will follow isolation of the desired TADF emitters and their self-assemblies. Training. This work entails organic synthesis, coordination chemistry to Pd (Schlenk techniques), and a large range of optoelectronic characterization techniques. Training on how to conduct DFT calculations will also be provided.