Electron Transport Materials: Synthesis, Properties and Device Performance


We report the design, synthesis and characterization, thermal and photophysical properties of two silane based electron transport materials, dibenzo[b,d]thiophen-2-yltriphenylsilane (Si?87) and (dibenzo[b,d]thiophen-2-yl)diphenylsilane (Siφ88) and their performance in blue organic light emitting devices (OLEDs). The utility of these materials in blue OLEDs with iridium (III) bis[(4,6-difluorophenyl)-pyridinato-N,C2’]picolinate (Firpic) as the phosphorescent emitter was demonstrated. Using the silane Siφ87 as the electron transport material (ETm), an EQE of 18.2% was obtained, with a power efficiency of 24.3 lm/W (5.8V at 1 mA/cm2), in a heterostructure. When Siφ88 is used, the EQE is 18.5% with a power efficiency of 26.0 lm/W (5.5V at 1 mA/cm2).

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L. Cosimbescu, L. Wang, M. Helm, E. Polikarpov, J. Swensen and A. Padmaperuma, "Electron Transport Materials: Synthesis, Properties and Device Performance," International Journal of Organic Chemistry, Vol. 2 No. 2, 2012, pp. 101-110. doi: 10.4236/ijoc.2012.22016.

Conflicts of Interest

The authors declare no conflicts of interest.


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