White electroluminescence

Figure 16. a) Electroluminescence of the reference system PVK/BND (left) and the white-light emitter PVK/THP/BND (right), b) Device configuration. 

K. Hutchison, J. Gao, G. Schick, Y. Rubin, F. Wudl, Bucky Light Bulbs White Light Electroluminescence from a Fluorescent C60 Adduct-Single Layer Organic LED , J. Am Chem. Soc. 1999,121,5611-5612. 

J Kido, K Hongawa, K Okuyama, and K Nagai, White light-emitting electroluminescent devices using the poly(Y-vinylcarbazolc) emitter layer doped with three fluorescent dyes, Appl. Phys. Lett., 64 815-817, 1994. 

M. Berggren, G. Gustafsson, O. Inganas, M.R. Andersson, T. Hjertberg, and O. Wennerstrom, White light from an electroluminescent diode made from poly[3(4-octylphenyl)- 2,2 -bithiophene] and an oxadiazole derivative, Appl. Phys. Lett., 76 7530-7534, 1994. 

J. Kido, M. Kimura, and K. Nagai, Multilayer white light emitting organic electroluminescent device, Science, 267 1332-1334 (1995). 

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). 

Y. Liu, J. Guo, H. Zhang, and Y. Wang, Highly efficient white organic electroluminescence from a double-layer device based on a boron hydroxyphenylpyridine complex, Angew. Chem. Int. Ed., 41 182-184 (2002). 

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

Figure 3.20. The CIE color diagram for electroluminescent devices, consisting of anode/Spiro-TAD/Spiro-quaterphenyl Rubrene/Alq3/cathode with different concentrations of rubrene. The spectrum shifts from blue to yellow, crossing the white point (E).

Red phosphors are formed either by heating white phosphorus or by exposing white phosphorus to sunlight. It is quite different from the explosive white phosphorus. For instance, when scratched on a surface, the heads of safety matches made of red phosphorus convert back to white phosphorus and ignite due to the heat of the shght friction of the match on a rough surface. Red phosphorus is also used in fireworks, smoke bombs, and pesticides and to make phosphoric acid, electroluminescent paints, and fertilizers. 

FIGURE 8. A SCP showing three-color white electroluminescence and its electroluminescent spectrum. 

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... 

In displays ZnO powders are used as green phosphors [169]. Recently, magnetron sputtered films of ZnO-based compounds, for instance Zn2SiO/ Mn or ZnGa204 Mn were used as green phosphors in thin-film electroluminescence displays [170,171]. Even white cathodoluminescence was observed for self-assembled ZnO micropatterns [172]. 

ZnO LED Au/p(i)-ZnO/n-ZnO single crystal/In structure grown by N2O plasma enhanced PLD, rectifying behavior, bluish-white electroluminescence [102]... 

Aluminium-pyrazol-5-one derivatives, (I), prepared by Kathirgamanathan [1] were effective as white light emitters and used in organic electroluminescent devices. Bis(2-phenylimidazo[l,2-a]pyridinato-N,C)iridium derivatives, (II), prepared by Lussier [2] were effective as phosphorescent emission agents. 

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