Efficient single-layer yellow-light emitting-diodes with ladder-type poly( p-phenylene)/poly(decyl-thiophene) blends

• Published in: Solid state communications Vol. 109; no. 7; pp. 455 - 459
• Main Authors: List, E.J.W., Holzer, L., Tasch, S., Leising, G., Scherf, U., Müllen, K., Catellani, M., Luzzati, S.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 11.02.1999; Elsevier
• Subjects: A.Semiconductors; Applied sciences; E.Luminescence; Electronics; Exact sciences and technology; Optoelectronic devices; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; E.Luminescence; A.Semiconductors; Voltage current curve; Thiophene derivative polymer; Yellow light; Photoluminescence; Phenylene polymer; Organic material; Electroluminescence; Ladder polymer; Light emitting diode
• ISSN: 0038-1098; 1879-2766
• DOI: 10.1016/S0038-1098(98)00586-9

We present the realisation of efficient polymer light emitting diodes (PLEDs) with yellow emission in a single-layer configuration. We found that the external electroluminescence-quantum efficiencies of PLEDs made of a blend of a blue emitting laddertype poly( p-phenylene) ( m-LPPP) and small amounts of an orange emitting poly(decyl-thiophene) (PDT) are significantly improved to 4.2% compared with PLEDs fabricated of pure m-LPPP (2%). In this paper, electroluminescence and photoluminescence properties of different PLEDs consisting of m-LPPP and different amounts of PDT are compared. The results are discussed in terms of excitation energy transfer of Förster type and charge transfer.