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Blended host ink for solution processing high performance phosphorescent OLEDs.

ABSTRACT: In order to solve the interface issues in solution deposition of multilayer OLED devices, a blended host concept was developed and applied to both spin-coating and inkjet printing of phosphorescent OLEDs. The blended host consists of 1,3-bis(carbazolyl)benzene (mCP) and1,3,5-tri(phenyl-2-benzimidazoly)-benzene (TPBi). Maximum current efficiency (CE) of 24.2 cd A-1 and external quantum efficiency (EQE) of 7.0% have been achieved for spin-coated device. Maximum CE and EQE of 23.0 cd A-1 and 6.7% have been achieved for inkjet printed device. The films deposited by printing and spin-casting were further researched to explore the effect of those different processing methods on device performance.

SUBMITTER: Lin T

PROVIDER: S-EPMC6497667 | biostudies-other | 2019 May

REPOSITORIES: biostudies-other

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Blended host ink for solution processing high performance phosphorescent OLEDs.

Lin Tong T Sun Xue X Hu Yongxu Y Mu Wanying W Sun Yuling Y Zhang Dongyu D Su Zisheng Z Chu Bei B Cui Zheng Z

Scientific reports 20190502 1

In order to solve the interface issues in solution deposition of multilayer OLED devices, a blended host concept was developed and applied to both spin-coating and inkjet printing of phosphorescent OLEDs. The blended host consists of 1,3-bis(carbazolyl)benzene (mCP) and1,3,5-tri(phenyl-2-benzimidazoly)-benzene (TPBi). Maximum current efficiency (CE) of 24.2 cd A<sup>-1</sup> and external quantum efficiency (EQE) of 7.0% have been achieved for spin-coated device. Maximum CE and EQE of 23.0 cd A<s ...[more]

PMID: 31048764

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