Electron transport in a starburst oxadiazole

In this article we report on the electron mobility of a starburst oxadiazole, 1,3,5 -[(4-tert. -butylphenyl) -2-oxadiazolyl] benzene. For direct evidence of the electron transport capability the charge drift mobility and its fil-ld dependence have been measured by the time-of-flight technique. The electron mobility showed a square root dependence of the electric field and was somewhat larger than that for PBD. In addition, the oxadiazole compound has been used as the electron transport layer (ETL) in light-emitting diodes (LEDs) together with poly(1,4-phenylene vinylene). The characteristics of these devices are compared to analogous LEDs with Alq(3) as the ETL. (C) 1997 American Institute of Physics.