Two novel blue phosphorescent host materials containing phenothiazine-5,5-dioxide structure derivatives.

Two novel D-A bipolar blue phosphorescent host materials based on phenothiazine-5,5-dioxide: 3-(9-carbazol-9-yl)-10-ethyl-10-phenothiazine-5,5-dioxide (CEPDO) and 10-butyl-3-(9-carbazol-9-yl)-10-phenothiazine-5,5-dioxide (CBPDO) were synthesized and characterized. The photophysical, electrochemical and thermal properties were systematically investigated. CEPDO and CBPDO not only have a high triplet energy but also show a bipolar behavior.