Chemical and Electronic Properties of Ba/Bis(2-methyl-8-quinolinolato)(4-phenylphenolato)Aluminum(III) Interfaces for Organic Light-Emitting Diodes
The chemistry, electronic structure, and electron-injecting characteristics at the interfaces that were formed between bis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum(III) (BAlq) and barium (Ba) were investigated using ultraviolet photoemission spectroscopy, near-edge X-ray absorption fine structure spectroscopy, X-ray photoemission spectroscopy, and current–voltage–luminance measurements. The device performance of organic light-emitting diodes (OLEDs), which have a glass/ITO/MoO3/2-TNATA/NPB/BAlq/Ba/Au structure, was significantly improved by inserting a Ba coverage (ΘBa) of 0.2 nm between BAlq and the cathode. For ΘBa's that were thicker than 0.2 nm, however, even though the electron-injecting barrier heights at the Ba-on-BAlq interfaces were all 0.1 eV, the device performance of the OLEDs with Ba at the interface was degraded with increasing ΘBa. This result indicates that the device performance is largely dependent on the interfacial chemical degradation of the BAlq molecule itself, rather than the electron-injecting barrier height that is determined by the width and chemical structure of the interface, and the formation of barium-induced new gap states at the Ba-on-BAlq interface.
No Reference information available - sign in for access.
No Citation information available - sign in for access.
No Supplementary Data.
No Article Media
Document Type: Research Article
Publication date: January 1, 2011
More about this publication?
- Journal for Nanoscience and Nanotechnology (JNN) is an international and multidisciplinary peer-reviewed journal with a wide-ranging coverage, consolidating research activities in all areas of nanoscience and nanotechnology into a single and unique reference source. JNN is the first cross-disciplinary journal to publish original full research articles, rapid communications of important new scientific and technological findings, timely state-of-the-art reviews with author's photo and short biography, and current research news encompassing the fundamental and applied research in all disciplines of science, engineering and medicine.
- Editorial Board
- Information for Authors
- Subscribe to this Title
- Terms & Conditions
- Ingenta Connect is not responsible for the content or availability of external websites