Donor-Acceptor materials and their applications in OLEDs and solar cells
Donor-acceptor-donor (D-A-D) materials having acridone as acceptor and carbazole as donor were synthesized for opto-electronic applications. Steady state and time dependent emission studied provided insight on their possible thermally activated delayed fluorescence (TADF) behaviour. The singlet-triplet energy gap (∆EST) was found to be as low 0.2eV. These materials were used green TADF emitters in organic light emitting diode (OLED) devices. Furthermore, an exciplex emission at 465 nm was observed in the blends of these D-A-D with polyvinylcarbazole (PVK). OLEDs fabricated with blend showed blue electroluminescence which is matching well with the exciplex photoluminescence. Apart from D-A-D in OLEDs, application of new class of high dipole moment materials in solar cell will also be discussed.