Combined Inter- and Intramolecular Charge-Transfer Processes for Highly Efficient Fluorescent Organic Light-Emitting Diodes with Reduced Triplet Exciton Quenching

Chang-Ki Moon; Katsuaki Suzuki; Katsuyuki Shizu; Chihaya Adachi; Hironori Kaji; Jang-Joo Kim

doi:10.1002/adma.201606448

Combined Inter- and Intramolecular Charge-Transfer Processes for Highly Efficient Fluorescent Organic Light-Emitting Diodes with Reduced Triplet Exciton Quenching

Adv Mater. 2017 May;29(17). doi: 10.1002/adma.201606448. Epub 2017 Mar 1.

Authors

Chang-Ki Moon¹, Katsuaki Suzuki², Katsuyuki Shizu², Chihaya Adachi³, Hironori Kaji², Jang-Joo Kim^{1

4}

Affiliations

¹ Department of Materials Science and Engineering, Seoul National University, Seoul, 151-742, South Korea.
² Institute for Chemical Research, Kyoto University, Uji, Kyoto, 611-0011, Japan.
³ Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, 744 Motooka, Nishi, Fukuoka, 819-0395, Japan.
⁴ Research Institute of Advanced Materials (RIAM), Seoul National University, Seoul, 151-742, South Korea.

PMID: 28247545
DOI: 10.1002/adma.201606448

Abstract

Inter- and intramolecular charge-transfer processes are combined using an exciplex-forming host and a thermally activated delayed fluorescent dopant, for fabricating efficient fluorescent organic light-emitting diodes along with the reduced efficiency roll-off at high current densities. Extra conversion on the host from triplet exciplexes to singlet exciplexes followed by energy transfer to the dopant reduces population of triplet excitons on dopant molecules, thereby reducing the triplet exciton annihilations at high current densities.

Keywords: exciplex; organic light-emitting diodes; thermally activated delayed fluorescence; triplet exciton quenching.