Enhanced electroluminescence from a thermally activated delayed-fluorescence emitter by suppressing nonradiative decay

Katsuyuki Shizu, Motoyuki Uejima, Hiroko Nomura, Tohru Sato, Kazuyoshi Tanaka, Hironori Kaji, Chihaya Adachi

Research output: Contribution to journalArticlepeer-review

59 Citations (Scopus)

Abstract

Thermally activated delayed-fluorescence (TADF) is a promising approach for realizing highly efficient organic light-emitting diodes (OLEDs). By controlling the spatial overlap between the frontier orbitals to suppress nonradiative decay, we develop a highly efficient TADF emitter, N1-[4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-N1-[4-(diphenylamino)-phenyl]-N4, N4-diphenylbenzene-1,4-diamine (DPA-TRZ). DPA-TRZ exhibits a photoluminescence quantum efficiency of 100% when doped into a host material, suggesting that nonradiative decay from its excited states is completely suppressed. Transient photoluminescence measurements confirm that DPA-TRZ emits TADF in a doped film. An OLED containing DPA-TRZ as a green emitter shows a maximum external quantum efficiency of 13.8%, which exceeds the theoretical limit for conventional fluorescent OLEDs. This high efficiency results from the effective generation of TADF and suppressed nonradiative decay in DPA-TRZ. Our molecular design strategy based on quantum chemistry provides a rational approach to control radiative and nonradiative decays for optimizing TADF materials.

Original languageEnglish
Article number014001
JournalPhysical Review Applied
Volume3
Issue number1
DOIs
Publication statusPublished - Jan 9 2015

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'Enhanced electroluminescence from a thermally activated delayed-fluorescence emitter by suppressing nonradiative decay'. Together they form a unique fingerprint.

Cite this