Electron photogeneration in a triblock co-polymer discotic liquid crystal

Discotic liquid crystals, exemplified by the triphenylene based systems, have been extensively researched due to an interest in their electronic properties, principally the carrier mobility along the stacks. The most widely used research technique for this purpose has been transient photoconduction and the time of flight technique and thus an interest in the photogeneration process has followed. In this work, we show an unusual polymeric discotic material with a main chain polymeric discotic liquid crystal capped either end with poly(ethylene oxide) blocks, in which the majority carriers are electrons in contrast to the usual holes. We also show that the photogeneration process is controlled at high fields by the effect of barrier lowering. (c) 2004 Elsevier B.V. All rights reserved.