Deep blue exciplex tandem OLEDs using n- and p-doped planar heterojunction as a charge generation layer. (4th August 2022)

• Record Type: Journal Article
• Authors: Fan, Yuxuan; Sun, Ahui; Tian, Yuhe; Zhou, Pengchao; Niu, Yixiao; Shi, Wei; Wei, Bin
• Is Part Of: Journal of physics. Volume 55:Number 31(2022)
• Publication Date: 2022-08-04
• Subjects: organic light-emitting diode -- tandem -- exciplex -- plant growth; Physics -- Periodicals; 530
• DOI: 10.1088/1361-6463/ac683d
• Languages: English
• ISSNs: 0022-3727

Abstract

Abstract: The tandem organic light-emitting diodes (OLEDs) have the advantages of small current density, high current efficiency (CE), and long lifetime. We have developed the conventional and inverted tandem OLEDs using n- and p-doped planar heterojunction as a charge generation layer (CGL). The CGL consists of the bathophenanthroline:Cs2 CO3 and N, N'-di-[(1-naphthalenyl)-N, N'-diphenyl]-1, 1′-biphenyl)-4, 4′-diamine:MoO3 bilayer structure to connect the deep blue- and deep red-emitting units. The turn-on voltage, luminescence, CE, and external quantum efficiencies of the conventional tandem OLED are 7.2 V, 5083 cd m −2, 8.45 cd A −1, and 13.94%, respectively, and the color rendering ability remains stable at a high current density of 60 mA cm −2 . Moreover, the efficiency roll-off of the inverted tandem OLED is optimized to 5.5% at a luminance of 1000 cd m −2 . Furthermore, a large-area (50 × 50 mm 2 ) parallel OLEDs with a tunable red-emitting area are fabricated. The development of the OLEDs provides a new direction for the application of OLEDs in plant growth.