| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1267560 | Organic Electronics | 2011 | 5 Pages |
Delayed electroluminescence (EL) measurements are used to investigate electroluminescence stability in phosphorescent organic light emitting devices (PHOLEDs) containing typical hole blocking layers (HBLs). The results show a strong correlation between the extent of hole blockage capacity of the HBL and the rate of deterioration in device EL efficiency, pointing to the major role that the build-up of hole space charges in the emitting layer (EML) plays in EL degradation. In this regard, the use of a strongly blocking material significantly increases the build-up of holes in the EML, and accelerates EL degradation.
Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Operational lifetimes of devices with various HBLs are studied. ► The results show a strong correlation between hole blockage capacity and the rate of deterioration in EL efficiency. ► Build-up of hole space charges in the emitting layer plays a major role in EL degradation. ► Use of a strongly blocking material (e.g. BCP) significantly accelerates EL degradation.
