Multipoint Hydrogen bonding of Iridium (III) complexes for influencing chromaticity
University of New Brunswick
Iridium complexes (with various N^C ligands) are undergoing intensive investigation, due to their excellent performance when used as emitters in phosphorescent organic light emitting diodes (PhOLEDs). To fulfill the requirements of full-colour OLED displays, the colour regulation (toward blue, green and red emissions) is highly desirable. In this thesis, we explore the colour tuning of different iridium emitters by host-guest assembly with DNA base-pair-like interactions in super strong hydrogen bonded arrays. Hydrogen bonds represent ideal interactions for holding supramolecular systems together, as they combine relatively strong intermolecular attractions with excellent reversibility. Our findings suggest that this methodology for colour tuning can eliminate the need for the synthetic manipulation of the ligand structure around iridium, which is often costly and time consuming. We analyze the association strength of iridium complexes when combined with different hetero-n-acenes in supramolecular systems. The incorporation of iridium metal in the H-bonded motifs contributes to the understanding of preorganized selfassemblies and opens new pathways in design of novel soft materials. Furthermore, we observe changes in the chromaticity of iridium complexes by simply varying the concentration of complement-guest, while examining changes in the emission properties. The presented work in this thesis focuses on supramolecular chemistry combined with strategic synthesis, which can lead to novel materials with dynamic properties.