Triarylboron‐Based Fluorescent Organic Light‐Emitting Diodes with External Quantum Efficiencies Exceeding 20 %. Issue 50 (13th November 2015)

• Record Type: Journal Article
• Authors: Suzuki, Katsuaki; Kubo, Shosei; Shizu, Katsuyuki; Fukushima, Tatsuya; Wakamiya, Atsushi; Murata, Yasujiro; Adachi, Chihaya; Kaji, Hironori
• Is Part Of: Angewandte Chemie international edition. Volume 54:Issue 50(2015)
• Page Start: 15231
• Page End: 15235
• Publication Date: 2015-11-13
• Subjects: boron -- donor‐acceptor systems -- electroluminescence -- fluorescence -- organic light‐emitting diodes; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201508270
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Triarylboron compounds have attracted much attention, and found wide use as functional materials because of their electron‐accepting properties arising from the vacant p orbitals on the boron atoms. In this study, we design and synthesize new donor–acceptor triarylboron emitters that show thermally activated delayed fluorescence. These emitters display sky‐blue to green emission and high photoluminescence quantum yields of 87–100 % in host matrices. Organic light‐emitting diodes using these emitting molecules as dopants exhibit high external quantum efficiencies of 14.0–22.8 %, which originate from efficient up‐conversion from triplet to singlet states and subsequent efficient radiative decay from singlet to ground states. Abstract : Triarylboron‐based emitters are reported that show high photoluminescence quantum yields and efficient up‐conversion from triplet to singlet states. Organic light‐emitting diodes (OLEDs) using these emitters show a maximum external quantum efficiency of 21.6 % for a sky‐blue OLED and 22.8 % for a green OLED.