The aim of the project is a development of efficient blue OLEDs utilizing semiconducting materials capable of triplet exciton harvesting through RISC in a host and host-guest energy transfer through HLCT states.
The tasks of the project:
1) development and investigation of compounds possessing HLCT states;
2) design and fabrication of blue OLEDs with a host:guest systems utilizing RISC in hosts and HLCT states;
3) characterization and optimization of the designed OLEDs;
4) documentation of the results.
The approach is helpful in suppressing non-radiative energy losses. The OLED structure can be optimized by a simplification and a selection of materials with appropriate energy levels. The maximum external quantum efficiency (EQE) of fabricated devices is expected to break the limit of 5% for fluorescent emitters; while, maximum power efficiency of 20+ lm/W will be achieved. The wavelength of peak of electroluminescence is expected to be at ca. 460 nm.
Guest:host systems utilizing exciton energy transfer through HLCT states instead of systems with a TADF host in blue OLED or phosphorescent PhOLED were not yet reported in the literature and has not been exploited in the previous or in the on-going projects. Newly developed organic semiconductors will be used for the investigation of the new type of host:guest systems. Management of the energy transfers in these novel systems will be the main new contribution of the project. Implementation of the project will provide the approach alternative to hyperfluorescence for obtaining the blue emission for OLEDs and tuning its efficiency and emission properties.
Project funding:
This research project is funded by the European Social Fund according to the 2014–2020 Operational Programme for the European Union Funds’ Investments, under measure’s No. 09.3.3-LMT-K-712 activity “Promotion of postdoctoral fellowships studies”.
Project results:
The research fellow will be able to publish the project results in the highly ranked scientific journals. The main scientific results of the project will be published in international peer reviewed 2+ journal papers with an impact factor on the Clarivate Analytics (formerly Thomson Reuters Web of Science database), e.g. Dyes and Pigments, Journal of Luminescence, Organic Electronics, etc. Spreading the results to broad audience of scientists, the research fellow will report the results in the international conferences or summer-schools due to the actuality and novelty of proposed project. The main scientific results of the project will be presented at 2+ international conferences (e.g. International Conference «Electronic processes in organic and inorganic materials» (ICEPOM), Baltic Polymer Symposium (BPS)).
Period of project implementation: 2020-08-17 - 2022-11-11
Project coordinator: Kaunas University of Technology
