Novel o-D-π-A arylamine/arylphosphine oxide hybrid hosts for efficient phosphorescent organic light-emitting diodes.

Three novel donor-acceptor type organic semiconductors PO1TPA , PO2TPA , and 2POTPA composed of arylamine donor and arylphosphine oxide acceptor were designed and synthesized through ortho -linking strategy. By varying the donor/acceptor ratio in these compounds, the effect of donor-acceptor connection pattern on the thermal stability, photophysical and optoelectronic properties of these materials was studied systematically. PO1TPA , PO2TPA , and 2POTPA exhibited high triplet energy due to the ortho -substituted fashion. As a result they were applied in blue, green, and red phosphorescent organic light-emitting diodes (PHOLEDs) as host materials. PO1TPA exhibited high electroluminescent performance for blue, green, and red devices with EQE over 20% due to its bipolar charge transport property. It is hoped that the results of this work could enrich the rational construction of host materials based on arylphosphine oxide and arylamine units via ortho -linking strategy for the development of highly efficient OLEDs. [ABSTRACT FROM AUTHOR]