Use this URL to cite or link to this record in EThOS:
Title: Synthesis, characterisation and optoelectronic properties of phosphorescent iridium complexes : from five to six-membered ring chelates
Author: Hierlinger, Claus
ISNI:       0000 0004 7431 3827
Awarding Body: University of St Andrews
Current Institution: University of St Andrews
Date of Award: 2018
Availability of Full Text:
Access from EThOS:
Access from Institution:
Here, the design, synthesis and characterisation and the optoelectronic properties of Ir(III) complexes for application in nonlinear optical and electroluminescent devices are described. The type of complexes varies from those of the form [Ir(C^N)2(N^N)]+ with conjugated and nonconjugated ligands (where C^N = cyclometalating ligand and N^N = neutral ligand) to those of the form [Ir(C^N^C)(N^N)Cl] (where C^N^C = tridentate tripod ligand). Chapter 1 gives an introduction into photophysics occurring in transition metal complexes and possible applications in visual displays. The background of nonlinear optical (NLO) properties and the use of transition metal complexes as NLO chromophores is described. In Chapter 2, the impact of the use of sterically congested cyclometalating ligands on the photoluminescence properties of cationic iridium(III) complexes and their performance in light-emitting electrochemical cells is investigated. Chapter 3 explores the use of electron donors on the cyclometalating ligand towards modulating the NLO properties of the complexes. Combining strongly electron-donating substituents on the C^N ligand and electron-accepting substituents on the N^N ligand results in strong NLO activity. Chapter 4 summarises a new series of cationic iridium(III) complexes bearing benzylpyridinato as cyclometalating ligands. The methylene spacer in the C^N ligands provides flexibility, resulting in two conformers. NMR studies combined with density functional theory (DFT) studies show how the fluxional behaviour is influenced by the choice of the ancillary ligand. In Chapter 5, Ir(III) complexes bearing an unusual nonconjugated bis(six-membered) tridentate tripod ligand of the form [Ir(C^N^C)(N^N)Cl] are introduced. Depending on the substitutions of the C^N^C ligand phosphorescence ranging from yellow to red was obtained. Substitution of the N^N results in a panchromatic NIR dye, suitable for DSSC applications. In Chapter 6, the concept of a nonconjugated ligand was expanded to the N^N ligand. Blue-green and sky-blue emission was obtained, demonstrating a strategy to successfully tune the emission to the blue.
Supervisor: Zysman-Colman, Eli ; Guerchais, Véronique Sponsor: Engineering and Physical Sciences Research Council (EPSRC) ; Région Bretagne
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available
Keywords: Iridium ; Photoluminescence ; QD412.I7H5 ; Iridium compounds--Synthesis ; Iridium compounds--Analysis ; Iridium compounds--Optical properties ; Phosphorescence ; Complex compounds