Researchers develop new thermally activated delayed fluorescence (TADF) materials
An international joint research group has succeeded in developing a new thermally activated, delayed-fluorescence (TADF) material that displays emission of light in colors from green to deep-red.
Through a detailed optical property investigation of this material, this group also confirmed that TADF was achieved through intersystem crossing (ISC) from the singlet excited state (1CT) to the triplet excited state (3LEA), a world first.
In addition, the external quantum efficiency (EQE) of the organic EL devices manufactured by using these newly developed TADF materials in their emitting layer reached 16 percent, greatly surpassing 5 percent, the limiting value obtained by conventional fluorescent materials.
These results will contribute to the research and development of white TADF light emitting devices for indoor and outdoor use through combination with TADF materials that emit light in shorter wavelengths (deep blue ~ yellow) which are currently being developed all over the world.
This research was published in the electronic version of Angewandte Chemie International Edition on April 6, 2016 (Germany time).