摘要
In this work, a novel molecule pyridinylfluorene/triphenylamine hybrid （TPyFTPA） with bulky steric hindrance effects has been synthesized successfully by substituting 9-（pyridine-2-yl）-fluoren-9-yl with triphenylamine （TPA） via Friedel-Crafts reaction, which possesses good thermal stability and triplet energy （ET） of 420 ℃ with 5% weight loss and 2.86 eV, respectively. Moreover, the bulky steric hindrance material shows high stable morphology by heating to 200 ℃ without finding melting phenomena and crystallization that is demonstrated by differential scanning calorimetry （DSC） curve. The bulky pyridinylfluorene end-capped TPA has been used as host material for blue phosphorescent organic light-emitting diodes （PhOLEDs） with maximum external quantum efficiencies （EQEs） of 2.7%, 3.7%, and 3.5%, at the doping ratios of 10%, 30%, and 40%, respectively. The performances of TPyFTPA-based blue PhOLEDs own wide concentration ranging from 10% to 40%, which indicates the bulky TPyFTPA might be a potential candidate for inexpensive products with simplifying process for the applications in full-color display and solid state lighting.
In this work, a novel molecule pyridinylfluorene/triphenylamine hybrid （TPyFTPA） with bulky steric hindrance effects has been synthesized successfully by substituting 9-（pyridine-2-yl）-fluoren-9-yl with triphenylamine （TPA） via Friedel-Crafts reaction, which possesses good thermal stability and triplet energy （ET） of 420 ℃ with 5% weight loss and 2.86 eV, respectively. Moreover, the bulky steric hindrance material shows high stable morphology by heating to 200 ℃ without finding melting phenomena and crystallization that is demonstrated by differential scanning calorimetry （DSC） curve. The bulky pyridinylfluorene end-capped TPA has been used as host material for blue phosphorescent organic light-emitting diodes （PhOLEDs） with maximum external quantum efficiencies （EQEs） of 2.7%, 3.7%, and 3.5%, at the doping ratios of 10%, 30%, and 40%, respectively. The performances of TPyFTPA-based blue PhOLEDs own wide concentration ranging from 10% to 40%, which indicates the bulky TPyFTPA might be a potential candidate for inexpensive products with simplifying process for the applications in full-color display and solid state lighting.
