Highly Air-Stable Electron-Transport Material for Ink-Jet-Printed OLEDs

摘要

A novel cross-linkable electron-transport material has been designed and synthesized for use in the fabrication of solution-processed OLEDs. The material exhibits a low LUMO level of -3.51eV, a high electron mobility of 1.5x10(-5)cm(2)V(-1)s(-1), and excellent stability. An average 9.3% shrinkage in film thickness was observed for the film after thermal curing. A maximum external quantum efficiency (EQE) of 15.6% (35.0cdA(-1)) was achieved for blue-phosphorescent OLEDs by spin-coating and 13.8% (31.0cdA(-1)) for an ink-jet-printed device, both of which are better than the EQE of a control device prepared by vacuum-deposition (see figure).