Hole-transport properties of a furan-containing oligoaryl

Abstract

We report the carrier transport properties of a furan-containing oligoaryl PF6, which contains no arylamine moiety in the molecular structure but exhibits competitive hole-transport capability in comparison with conventional arylamine-based hole-transport materials often used in organic light-emitting devices (OLEDs) and xerography. Thin films of this compound exhibit both morphological stability and appropriate energy levels for OLED applications. OLEDs using PF6 as the hole-transport layer show low turn-on voltage, high efficiency, and high brightness competitive with those using conventional hole-transport materials, strongly indicating superior hole-transport properties of PF6. The carrier mobility of PF6 was directly measured by the time-of-flight transient photocurrent technique under various temperatures and electric fields. Nondispersive hole transport was observed and a room-temperature hole mobility in excess of 10−3 cm2/V s was obtained under high fields. The field and temperature dependence of hole mobility were analyzed and were found consistent with the Bässler (disorder) formalism.