Lowest unoccupied molecular orbital managing function of CN-substituted dibenzofuran in high triplet energy hosts for blue thermally-activated delayed fluorescence organic light-emitting diodes. Issue 42 (14th October 2021)

• Record Type: Journal Article
• Authors: Byeon, Sung Yong; Lee, Kyung Hyung; Lee, Jun Yeob
• Is Part Of: Journal of materials chemistry. Volume 9:Issue 42(2021)
• Page Start: 15095
• Page End: 15101
• Publication Date: 2021-10-14
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d1tc02624k
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : The effect of lowest unoccupied molecular orbital management of high triplet energy electron transport type hosts in organic light-emitting diodes was investigated by synthesizing three hosts derived from CN-modified dibenzofuran. Abstract : The effect of lowest unoccupied molecular orbital (LUMO) management of high triplet energy electron transport type hosts on the device performance of blue thermally-activated delayed fluorescence (TADF) organic light-emitting diodes was investigated by synthesizing three hosts derived from 3, 6-dicyanocarbazole, CN-modified dibenzofuran, and benzonitrile. The three host materials were designed to share a highly twisted molecular structure and high triplet energy above 3.0 eV with different LUMO distributions by controlling the CN substituents in the dibenzofuran unit. A wide LUMO distribution due to the CN substituents improved the electron transport properties of the hosts. The host materials were applied as electron transport type hosts in a mixed host system with a hole transport type host of 3, 3′-di(9 H -carbazol-9-yl)-1, 1′-biphenyl. Among the hosts, the electron transport type host with two CN-substituted hosts demonstrated a high EQE of 19.3% and about a 60% improved device lifetime in the blue TADF devices due to the wide LUMO dispersion.