Electron Transport Materials: Synthesis, Properties and Device Performance

Lelia Cosimbescu, Liang Wang, Monte L. Helm, Evgueni Polikarpov, James S. Swensen, Asanga B. Padmaperuma

Department of Chemistry, Fort Lewis College, Durango, USA.
Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland, USA.

DOI: 10.4236/ijoc.2012.22016                

Abstract

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).

Keywords

Electron Transport; OLED; Triplet Energy

Conflicts of Interest

The authors declare no conflicts of interest.

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