Heteroleptic light-emitting copper(I) complexes with possible applications in light-emitting electrochemical cells

The overall aim of this project was the design, synthesis and characterization of copper(I) complexes that, upon
excitation, emit light in the region of the electromagnetic spectrum that is visible to the human eye. The complexes
are incorporated into light-emitting devices and their electroluminescent behaviour was studied and the results used
to further optimize the compounds in an iterative manner. The main focus was on complexes of the general formula
[Cu(P^P)(N^N)][PF6], where P^P is a chelating bisphosphane and N^N is a 2,2'-bipyridine (bpy), phenanthroline or
moiety of similar structure. The commercially available bisphosphanes, bis(2-(diphenylphosphino)phenyl)ether
(POP) and 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (xantphos) were chosen as our standard P^P chelating
ligands in order to investigate the role of the N^N chelating ligand and study the effects of modifications on the bpy
or its derivatives on the copper complexes. Detailed structural, photophysical and electrochemical characterizations,
as well as quantum chemical calculations of the synthesized complexes were carried out and the most promising
compounds were evaluated in light-emitting electrochemical cells (LECs). In order to make the reader familiar with
the topic, we start with the motivation for this project and continue with an introduction about general properties of
copper and its emissive complexes. The principle of thermally activated delayed fluorescence (TADF) is explained
and the characteristics of LECs are described. In Chapter I, a series of complexes with alkyl substituents in different
positions in the bpy and phen ligands are compared. In Chapter II, the results of the investigation of complexes with
chloro-and bromo-substituted bpy ligands are shown. The effect of CF3 substitution in the bpy on complex and
device properties is exposed in Chapter III. The subject of Chapter IV is the fortuitous formation of an inorganic
coordination polymer. The potential of an alkyl phosphane as a ligand for emissive copper(I) complexes was
evaluated and the resulting complexes are shown in Chapter V. A side project with dimeric silver(I) complexes and
their self-assembling properties is presented in Chapter VI. The thesis is concluded with an outlook about projects
for the near future and the potential of copper(I) based light-emitting electrochemical cells as an illumination
technique is discussed.