Novel hole-transporting hydrazones

Abstract

Photoelectric properties of the glass-forming 9-[2-(9H-carbazol-9-yl)-cyclobutyl]-9H-carbazole- and 9-[6-(9H-carbazol-9-yl)-hexyl]-9H-carbazole-based hydrazones with the glass transition temperature ranging from 81 to 136 degreesC are reported. The ionisation potentials of the amorphous films of these compounds established by the electron photoemission technique in air range from 5.39 to 5.53 eV. The hole-drift mobility of 1 X 10(-3) cm(2) V-1 s(-1) at an applied electric field of 1.0 x 10(6) V cm(-1) was observed in the amorphous film of 9-[2-(9H-carbazol-9-yl)-cyclobutyl]-9H-carbazole-3-carbaldehyde N,N-diphenylhydrazone by the time of flight technique.