Synthesis and light-emitting properties of bipolar oligofluorenes containing triarylamine and 1,2,4-triazole moieties

A facile approach for synthesis of bipolar oligofluorenes, TAZ-OF(n)-NPh, n) 2 or 3 end-capped with hole-transporting diphenylamino and electron-transporting triazole moieties by Suzuki cross-coupling as the key reaction has been developed. This novel bipolar oligofluorenes exhibited blue-emission, high thermal and morphological stabilities. The single-layer OLED based on TAZ-OF(2)-NPh exhibited superior device performance with a maximum luminance of 1128 cd m(-2) and luminance efficiency of up to 0.83 cd A(-1).