Speeding‐up Thermally Activated Delayed Fluorescence in Cu(I) Complexes Using Aminophosphine Ligands

Abstract

AbstractLuminescent copper(I) complexes presenting thermally activated delayed fluorescence (TADF) have drawn attention as emitters for organic light emitting diodes (OLEDs). While the majority of ligands used have nitrogen as donor atoms, in this work, we report the synthesis and characterization of three copper(I) complexes with the diimine ligand 1,10‐phenanthroline and aminophosphine‐derived ligands containing the piperazine and N,N’‐dimethylethylenediamine to evaluate their effect into the emission properties. The photophysical studies as a function of temperature suggested TADF and phosphorescence emission, supported by detailed density functional theory (DFT) calculations. The use of aminophosphine ligands enhance the TADF decay pathway in comparison with copper complex containing the usual POP ligand. These properties, combined with the appropriate HOMO‐LUMO energy levels and thermal stability, make these compounds a promising alternative for application in OLEDs.