Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1443568 | Synthetic Metals | 2006 | 5 Pages |
Abstract
This paper reports on the use of an electron transport layer (ETL) in polymer light-emitting diodes based on poly(2,5-bis(3â²,7â²-dimethyl-octyloxy)1,4-phenylene-vinylene) (BDMO-PPV). This ETL is inserted between BDMO-PPV and a calcium cathode as a hole blocking layer (HBL). A novel phenyleneethynylene derivative (ImPE) is proposed and compared to well-known materials such as tris(8-hydroxyquinoline) aluminum (Alq3) and bathocuproïne (BCP). Efficient hole blocking is achieved leading to yield improvements at low luminances. With a 8Â nm-thick ImPE layer, at 1Â cd/m2, the power efficiency reaches 1.2Â lm/W whereas a BDMO-PPV-only PLED exhibits a 0.13Â lm/W power efficiency. ImPE enables to reach higher performances than Alq3 for low luminances (<20Â cd/m2). However, for luminances higher than 350Â cd/m2, it is demonstrated that the hole blocking in no more efficient because of a too strong electric field.
Related Topics
Physical Sciences and Engineering
Materials Science
Biomaterials
Authors
G. Wantz, O. Dautel, L. Vignau, F. Serein-Spirau, J.P. Lère-Porte, L. Hirsch, J.J.E. Moreau, J.P. Parneix,