Luminescence properties of poly(9,9-dioctylfluorene)/polyvinylcarbazole blends: Role of composition on the emission colour stability and electroluminescence efficiency

• Type: Article in International Scientific Journal
• Date: 2010

Authors

Bernardo, G (Author) Other; Charas, A (Author) Other; Morgado, J (Author) Other

Journal

Title: Journal of Physics and Chemistry of Solids

Vol. 71

Pages: 340-345

ISSN: 0022-3697

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 16 Citations

Scopus - 16 Citations

Other information

Authenticus ID: P-003-8TJ

DOI: 10.1016/j.jpcs.2009.12.087

Abstract (EN): Light-emitting diodes (LEDs), based on blue-emitting polyfluorenes are usually prone to the appearance of a contaminant green emission (centered around 520 nm), leading to an apparent whitish light emission. We find that, for LEDs based on poly(9,9-dioctylfluorene), PFO, the blending with the hole transporting polyvinylcarbazole, PVK, can suppress such green emission. LEDs based on a PFO/PVK blend with a 1:2 weight ratio and with aluminum cathodes show a quite stable blue emission. This result reveals the important role played by the interchain interactions on the observed contaminant green emission. In addition, we observe that in Al-based devices blending causes a decrease in EL efficiency while in Mg-based devices we obtained higher efficiencies with the blend PFO:3PVK when compared with neat PFO-based devices.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 6