Prof. Z. Valy Vardeny’s group from University of Utah and their collaborators made significant achievements on organic LEDs and published their work on Advanced Functional Materials.
In this research investigationthin films and OLED devices based on donor (D)- acceptor (A) exciplex blend doped with fluorescence emitters was used. Specifically theyused N,N,N′,N′-Tetrakis(4-methoxyphenyl)benzidine (MeO-TPD) as the donor, tris-[3-(3-pyridyl)mesityl]borane (3TPYMB) as the acceptor, and tetraphenyldibenzoperiflanthene (DBP) as the fluorescent emitter. We found a respectable magneto-electroluminescence (MEL) value of ~16% when doped with 2% DBP. We also used magneto-photoluminescence (MPL) to further investigate and validate the proposed underlying mechanism for the MEL in this exciplex blend. They found a decrease in the MEL activation energy compare to that in the undoped D-A exciplex blend, which may explain the enhanced quantum efficiency of this type of devices.
This work may help researchers in the field of organic light emitting devices to gain deeper understanding of MEL in exciplex-type OLEDs. In addition, the obtained MEL value at room temperature (and above) may lead to potential applications in the displays industry, or memory devices after carefully optimizing the D-A materials, their composition and dopant concentration in the devices.