%A Jin Cao(曹进), Jing-Wei Xie(谢婧薇), Xiang Wei(魏翔), Jie Zhou(周洁), Chao-Ping Chen(陈超平), Zi-Xing Wang(王子兴), Chulgyu Jhun(田哲圭) %T Bright hybrid white light-emitting quantum dot device with direct charge injection into quantum dot %0 Journal Article %D 2016 %J Chin. Phys. B %R 10.1088/1674-1056/25/12/128502 %P 128502-128502 %V 25 %N 12 %U {https://cpb.iphy.ac.cn/CN/abstract/article_119239.shtml} %8 2016-12-05 %X

A bright white quantum dot light-emitting device (white-QLED) with 4-[4-(1-phenyl-1H-benzo[d]imidazol-2-yl)phenyl]-2-[3-(tri-phenylen-2-yl)phen-3-yl]quinazoline deposited on a thin film of mixed green/red-QDs as a bilayer emitter is fabricated. The optimized white-QLED exhibits a turn-on voltage of 3.2 V and a maximum brightness of 3660 cd/m2@8 V with the Commission Internationale de l'Eclairage (CIE) chromaticity in the region of white light. The ultra-thin layer of QDs is proved to be critical for the white light generation in the devices. Excitation mechanism in the white-QLEDs is investigated by the detailed analyses of electroluminescence (EL) spectral and the fluorescence lifetime of QDs. The results show that charge injection is a dominant mechanism of excitation in the white-QLED.