Structural Modification of Carbene-Metal-Amide Complexes Towards Acquisition of Thermally Activated Delayed Fluorescence Blue Light OLED Emitters (2020.-2022.)

Project coordinator: Dr. Chem. Kaspars Traskovskis (RTU)

Responsible form UL ISSP side: Dr. Phys. Aivars Vembris

Total cost: 300 000 EUR

Duration (years): 2020-2022

LZP FLPP No. lzp-2019/1-0231

During the last decade the use of organic light emitting diodes (OLEDs) has vastly increased, mainly due to applications in mobile device displays and OLED-TVs. Despite the fact that the global market evaluation of this industrial sector reaches several tens of billions euros, its further expansion is met with important challenges. The currently used emitters are based on expensive transition metal (Pd, Ir) complexes, what notably increases production cost of the devices and creates environmental sustainability concerns. At the same time, the lack of triplet-harvesting blue emitters lowers the energy efficiency of OLEDs. Carbene-metal-amide complexes are a recently discovered emitter class, which instead of rare transition metals uses relatively abundant and cheap alternatives like copper and silver. Due to thermally activated delayed fluorescence (TADF) process these materials show performance characteristics that are comparable with the currently practically used compounds. The objective of this project is to develop efficient, low cost blue emitting OLED emitters that are based on modified carbene-metal-amide complex structures. Blue light emission will be ensured by a tuning of molecular orbital energy levels with the use of novel carbene and amide fragments. The activities of the project will involve material synthesis, measurements of photophysical properties, integration of new-synthesized emitters in OLEDs and device characterization.