Poly , blue light emitting diodes

J Griiner, PJ Hamer, RH Friend, HJ Huber, U Scherf, and AB Holmes, A high efficiency blue-light-emitting diode based on novel ladder poly(p-phenylene)s, Adv. Mater., 6 748-752, 1994. 

A.P. Kulkarni and S.A. Jenekhe, Blue light-emitting diodes with good spectral stability based on blends of poly(9,9-dioctyfluorene) interplay between morphology, photophysics, and device performance, Macromolecules, 36 5285-5296, 2003. 

M. Fahlman, J. Birgersson, K. Kaeriyama, andW.R. Salaneck, Poly(2,5-diheptyl-l,4 -phenylene-a/t -2,5-thienylene) a new material for blue-light-emitting diodes, Synth. Met., 75 223-228,1995. 

Y. Yang, Q. Pei, and A.J. Heeger, Efficient blue light-emitting diodes from a soluble poly (p-phenylene) internal field emission measurement of the energy gap in semiconducting polymers, Synth. Met., 78 263-267, 1996. 

G. Grem, C. Paar, J. Stampfl, G. Leising, J. Huber, and U. Scherf, Soluble segmented stepladder poly(p-phenylencs) for blue-light-emitting diodes, Chem. Mater., 7 2-4, 1995. 

Y. Yang, Q. Pei, A. J. Heeger, Efficient Blue Light-Emitting Diodes from a Soluble Poly (Para-Phenylene) Internal Field Emission Measurement of the Energy Gap in Semiconducting Polymers. Synth. Met. 1996, 78, 263-267. 

Zarras, P, J.D. Stenger-Smith, G.S. Ostrom, L.H. Merwin, and C.K. Webber. 1999. Synthesis of cyano derivatives of poly[2,5-bis(N-methyl-N-alkylamino)phenylene vinylene] S for use as potential blue light-emitting diodes. Abstracts Pap Am Chem Soc 218 11562—11562. 

Poly(2,5-pyridyl) commonly know as poly(pyridine) has been the subject of considerable research effort as it luminesces in the blue region of the spectrum and may have uses in light emitting diodes (LEDs). Vaschetto and co-workers [103] reported a series of calculations on the molecule and its oligomers. The calculations included both the B3LYP and B3P88 density functions, Hartree-Fock calculations and a periodic solid-state DFT calculation using linear muffin tintype orbitals (LMTO). 

Y Yang, Q Pei, and AJ Heeger, Efficient blue polymer light-emitting diodes from a series of soluble poly(paraphenylene)s, J. Appl. Phys., 79 934—939, 1996. 

W.-L. Yu, Y. Cao, J. Pei, W. Huang, and A.J. Heeger, Blue polymer light-emitting diodes from poly(9,9-dihexylfluorene- alt-co-2,5- didecyloxy-p-phenylene), Appl. Phys. Lett., 75 3270-3272, 1999. 

T. Yirgili, D. Lidzey, and D.D.C. Bradley, Efficient energy transfer from blue to red in tetra-porphyrin-doped poly(9,9-dioctylfluorene) light-emitting diodes, Adv. Mater., 12 58-62, 2000. 

Y. Xiaohui, H. Yanbing, W. Zhenjia, C. Xiaohong, X. Zheng, and X. Xurong, Blue polymer light emitting diode based on ladder poly(p-phenylene), Thin Solid Films, 363 211-213, 2000. 

Due to the large band gap and high triplet energy level of the poly(3, 6-dibenzosilole) 5, the copolymer is an excellent host for the fabrication of blue polymer phosphorescent light-emitting diodes. A high external quantum efficiency (t/el) of 4.8% and a luminance efficiency of 7.2 cd/A at 644 cd/m2 have been achieved for blue phosphorescence devices (emission peak (AEL) at 462 nm, CIE coordinates x = 0.15,y = 0.26). The performances of the devices are much better than those reported for blue phosphorescent devices with poly(A--viny 1 cabarzo 1 e) (PVK) as the host.32... 

Phenylene-based polymers are one of the most important classes of conjugated polymers, and have been the subject of extensive research, in particular as the active materials in light-emitting diodes (LEDs) [1,2] and polymer lasers [3]. These materials have been of particular interest as potential blue emitters in such devices [4], The discovery of stable blue-light emitting materials is a major goal of research into luminescent polymers [5]. Poly(para-phenylene) (PPP, Scheme 1, 1) is a blue emitter [6], but it is insoluble and so films of PPP have to be prepared via precursor routes [7]. Substitution with long alkyl... 

Abstract Poly(dibenzosilole)s are an emerging class of polymers with similar optoelectronic properties to polyfluorenes. With increased stability towards oxidation, several poly(dibenzosilole)-based devices, such as light emitting diodes, have shown improved performance over their polyfluorene counterparts. As a consequence of reduced conjugation in the polymer chain, some poly(dibenzosilole)s have high triplet excited state energies, which make them suitable hosts for blue triplet emitters in electrophosphores-cent devices. 

The first PLEDs based on 3,6-carbazoles was achieved in 1996, by Zuppiroli and coworkers with a poly(7V-butyl-3,6-carbazole) in a single-layer device with ITO and A1 electrodes [123]. Diodes produced blue emission with a low EL performance (.Vext = 0.07% and a few cd/m2 at 15 V). Aiming at increasing the EL performances, five-layers OLEDs based on small molecules were fabricated using carbazole dimers as emitters. A pure blue light-emitting device has been achieved with CIE coordinates a = 0.158, y = 0.169, Apeak = 456nm, a luminance of 1000 cd/m2, luminance efficiency of 4.7 cd/A at 10 V and a r]ext = 33% [125]. 

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