White polymeric light-emitting diode based on a fluorene polymer/Ir complex blend system

Hameed A. Al Attar; Andy P. Monkman; Mustafa Tavasli; Sylvia Bettington; Martin R. Bryce

doi:10.1117/12.629482

29 July 2005 White polymeric light-emitting diode based on a fluorene polymer/Ir complex blend system

Hameed A. Al Attar, Andy P. Monkman, Mustafa Tavasli, Sylvia Bettington, Martin R. Bryce

Proceedings Volume 5961, Building European OLED Infrastructure; 596108 (2005) https://doi.org/10.1117/12.629482
Event: Workshop on Building European OLED Infrastructure, 2005, Cambridge, United Kingdom

Abstract

New extended fluorenylpyridine ligands FlnPy (n=1,3,5) and their triscyclometalated iridium (III) complexes Ir[FlnPy]₃ 3, 4, and 5 have been synthesised and their photophysical properties have been studied. The lowest energy (emissive) excited state of the complexes 3-5 is dominated by ligand centered ³(π→π*) triplet states, as observed in their ligands. Efficient white-polymeric light-emitting diodes (PLED) were fabricated as a single active layer containing blue emitting poly (9,9-bis(2-ethylhexyl)fluorine-2,7- diyl) endcapped with bis(4-methylphenyl)phenylamine (PF2/6am4), and yellow-orange emitting from Iridium complex 4. The fluorene-like ligands in the blended device prevent phase segregation and also enhance energy transfer from the polymer host to the guest due to efficient overlap of wavefunction (Dexter process) and host singlet emission and guest absorption bands (F&diaero;rster process) which reduces the loading level required to produce white emission. The two emitted colours complement each other and doping levels between 2% to 3% produce white emission. Above a certain current density depending on the doping level the device CIE coordinates become bias independent and a stabilised white emission can be obtained. A white emission PLED (coordinate (0. 348, 0.367) of peak external quantum efficiency (EQE) of 2.8 %, and luminance of 16000 cd/m2) at applied voltage of 5V (ie. 4.57 cd/A) was obtained. device CIE coordinates become bias independent and a stabilised white emission can be obtained. A white emission PLED (coordinate (0. 3477, 0.3667) of peak external quantum efficiency (EQE) of 2.8 %, and luminance of 16000 cd/m2 at applied voltage of 5V (ie. 4.57 cd/A) was obtained.

Citation Download Citation

Hameed A. Al Attar, Andy P. Monkman, Mustafa Tavasli, Sylvia Bettington, and Martin R. Bryce "White polymeric light-emitting diode based on a fluorene polymer/Ir complex blend system", Proc. SPIE 5961, Building European OLED Infrastructure, 596108 (29 July 2005); https://doi.org/10.1117/12.629482

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available