9-Phenylcarbazole–Based Hydrazone Twin Compounds as P-Type Organic Semiconductors

Abstract

Hole transporting glass-forming low-molar-mass hydrazones containing 9-phenylcarbazole moiety were synthesized and characterized by NMR-, infrared- and mass spectrometries. The thermal, optical and photoelectrical properties of the synthesized compounds are reported. Compounds containing 1,3-benzendithiol linking bridge were isolated as amorphous materials therefore differential scanning calorimetry experiments revealed glass transitions approximately at 60°C. The ionization potentials of the synthesized compounds were measured by electron photoemission technique in air range from 5.23 eV to 5.4 eV. Hole drift mobilities in the films of the solid solutions of some of the synthesized hydrazones in bisphenol Z polycarbonate measured by the time-of-flight technique exceed 10⁻⁵ cm² V⁻¹ s⁻¹ at high electric fields.

Keywords:

• Carbazole
• glass transition
• hole transport
• hydrazone

Acknowledgment

Financial support of this research by the Research Council of Lithuania (grant No. TAP67/2010) is gratefully acknowledged. Dr. V. Gaidelis is thanked for the help in ionization potential measurements.

Notes

¹Determined by DSC, scan rate 20°C/min, N₂ atmosphere.

²Onset of decomposition determined by TGA, heating rate 10°C/min, N₂ atmosphere.

^a Heating rate 10°C/min.