Tetraphenylsilane group containing carbazoles as high triplet energy host materials for solution-processable PhOLEDs

WOS: 000362850500002A series of solution processable, wide band-gap host materials composed of carbazole and tetraphenylsilane groups were designed and synthesized. Their thermal, electrochemical, and photophysical properties were fully investigated. The introduction of bulky tetraphenylsilane and tert-butyl groups around the carbazole led to high glass transition temperatures (T-g) between 120 and 204 degrees C. The triplet energies (E-T) of the synthesized materials were examined by low temperature (77 K) photoluminescence studies and determined as E-T > 2.6 for all compounds. Phosphorescent organic light-emitting devices with the ITO/PEDOT:PSS/EML/TPBi/Cs2CO3/Al device structure were fabricated by using synthesized materials as the host and two kinds of phosphorescent emitters, FIrpic and Ir(ppy)(3), as the guests. The highest luminous and power efficiency values obtained by using FIrpic were 3.6 cd A(-1) and 1.48 lm W-1, respectively, with commission International de I'Eclairage (CIE) coordinates of (0.17, 0.36), whereas these values were 7.8 cd A(-1) and 2.9 lm W-1 for the device structure when Ir(ppy)(3) was used as the guest [CIE (0.28, 0.62)].Scientific and Technological Research Council of Turkey (TUBiTAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [113Z253]This work was supported by the Scientific and Technological Research Council of Turkey (TUBiTAK) (Project #: 113Z253). The authors would like to thank Dr Armagan Kmal for productive discussions on the numerical calculations, which were performed at TUBITAK ULAKBIM, High Performance and Grid Computing Center (TRUBA Resources)