Researchers from Russia's Ural Federal University developed a new OLED emitters based on cyanopyrazine-enhanced fluorophores. The presence of cyanogroup substance in the composition of fluorophores significantly increases the efficiency of the OLED emitters.
The researchers say that they have modified the pyrazine-based push-pull system with cyanogroup and studied how this affected the photophysical properties of the fluorophores and the performance of OLED devices based on these materials.
The researchers, it seems, expected the new emitter to exhibit TADF emission, but due to the peculiarities of the structure of the initial substance, TADF did not arise. But it turned out that the the introduction of a cyanogroup intensifies intermolecular interactions, as a result of which not individual molecules but complexes of molecules begin to fluoresce. As a consequence, the increase in luminescence intensity was from 2.4 to 20 times, and the brightness of the emitted light was up to 75 times.
The researchers created several prototypes that all exhibited the high performance.
