Suppressed efficiency roll-off in blue light-emitting diodes by balancing the spatial charge distribution
Suppressed efficiency roll-off in blue light-emitting diodes by balancing the spatial charge distribution
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通过平衡空间电荷分布抑制蓝色发光二极管的效率滚降
DOI：
10.1039/d0tc03295f
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发表时间：
2020-10
影响因子：
6.4
通讯作者：
Wenyu Ji
中科院分区：
文献类型：
--
作者：
FangFang Wang;Huimin Zhang;Qingli Lin;Jiaojiao Song;Huaibin Shen;Hanzhuang Zhang;Wenyu Ji
Quantum dot-based light-emitting diodes (QLEDs) have been considered as a highly promising candidate for lighting and display applications. Their peak external quantum efficiencies (EQEs) are now approaching the theoretical values for red/green/blue QLEDs. However, these peak values are commonly obtained at low current densities (low brightness), whereas their efficiency usually exhibits a quick roll-off with increasing current densities, especially for blue QLEDs, limiting the operation lifetime and applications. In this study, we demonstrated suppressed efficiency roll-off and bright blue QLEDs by using propanethiol-modified ZnCdSeS QDs as the emitters. A peak EQE of 9.9% is achieved at a luminance of 1040 cd m−2, along with a high luminance up to 52 360 cd m−2. Moreover, the reduction of the EQE is less than 50% of the peak value until the luminance is as high as 28 260 cd m−2, highly superior to the control device. Most importantly, higher than 75% of the peak EQE value is sustained within the luminance range from 100 to 10 000 cd m−2, which has already reached the threshold values for applications in both displays and lighting. We attribute these major advances to the transport-enhancement of short-chain ligands outside the QDs, which improves both conductivity and injection balance of the emissive layer, reducing the quenching processes induced by accumulated charges.
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影响因子：
41.2
作者：
Chuang, Chia-Hao M.;Brown, Patrick R.;Bulovic, Vladimir;Bawendi, Moungi G.
通讯作者：
Bawendi, Moungi G.
影响因子：
8.6
作者：
Shirasaki, Yasuhiro;Supran, Geoffrey J.;Bulovic, Vladimir
通讯作者：
Bulovic, Vladimir
影响因子：
41.2
作者：
D. Milliron
通讯作者：
D. Milliron
高度稳定的 QLED，通过量子点结构定制改善空穴注入
影响因子：
16.6
作者：
Cao, Weiran;Xiang, Chaoyu;Qian, Lei
通讯作者：
Qian, Lei
DOI：
10.1002/pola.24127
发表时间：
2010-08
期刊：
Journal of Polymer Science Part A
影响因子：
--
作者：
M. Thesen;B. Höfer;Marc Debeaux;S. Janietz;A. Wedel;A. Köhler;H. Johannes;H. Krueger
通讯作者：
M. Thesen;B. Höfer;Marc Debeaux;S. Janietz;A. Wedel;A. Köhler;H. Johannes;H. Krueger