Derivatives of 2,5-dimercapto-1,3,4-thiadiazole as hole transporting materials

Abstract

The new hole transporting materials with molecules consisting of two hydrazone branches linked with a flexible thiadiazole ring and two hydroxyl groups containing a central bridge were synthesized and investigated. These transporting materials are low-molecular glasses and can be used without binder materials. The ionization potential of the materials is in the range of 5.08-5.31 eV. The highest hole mobility, reaching 10-4 cm²/Vs at the 6ּ10(5) V/cm electric field, was observed in the transporting material with dimethyltriphenylamine or triphenylamine moieties. It is about one order of magnitude higher than in diethylaniline or ethylcarbazole moieties containing materials.