White electroluminescent material

The EL spectrum has multiple peaks when more than one mode of the cavity overlaps the free-space emission spectrum. It is possible to realize a white LED with a single electroluminescent material such as Alq by employing a two-mode microcavity device structure in which one of the modes is centered near 480 nm and the other near 650 nm. Such an electroluminescence spectrum, for which the CIE coordinates are (0.34, 0.386),13 is shown in Fig. 4.6. The approximate spectrum calculated with Eq. (4) is also shown in Fig. 4.6. With very minor changes in the device design, it is easy to achieve (0,33, 0.33). For comparison, the CIE coordinates of a noncavity Alq LED are (0.39, 0.56). 

Xue, S.,Yao, L., Shen, E, Gu, C., Wu, H., Ma,Y, 2012. Highly efficient and fully solution-processed white electroluminescence based on fluorescent small molecules and a polar conjugated polymer as the electron-injection material. Adv. Funct. Mater. 22,1092-1097. 

MEH-PPV is one of the most studied electroluminescent materials. It finds use as a CP in solar cells and carbon nanotube OLEDs [103, 104, 105]. Useful in soducing bright and efficient white polymeric LEPs [106]. Although solid-state lasing has yet to be demonstrated in an organic LEP, MEH-PPV has been proven to be a promising laser dye due to its high fluorescrace efficiency in solution [107]. 

Y. Hamada, T. Sano, H. Fujii, Y. Nishio, H. Takahashi, and K. Shibata, White light emitting materials for organic electroluminescent devices, Jpn. J. Appl. Phys., 35 L1339-L1341 (1996). 

Blue luminescent materials for organic electroluminescent devices White light-emitting organic electroluminescent devices Blue organic electroluminescent devices... 

Metal complexes with Schiff base ligands have useful applications in organic optoelectronics due to their outstanding photoluminescent (PL) and electroluminescent (EL) properties, and their ease of synthesis, which readily allows structural modification for optimization of material properties.28 Hamada and co-workers pioneered the use of zinc(II) Schiff base complexes as blue to greenish white emitters for EL devices. We have demonstrated Pt(II) Schiff base triplet emitters as yellow dopants for organic light-emitting devices... 

Rai V. K., Srivastava R., Kamalasanan M. N. White organic electroluminescence from fluorescent bis (2-(2-hvdroxvphenyl) benzoxazolate) zinc doped with phosphorescent material lournal of Luminescence, 130, 2, (February 2010), 249-253... 

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