title: Efficient Organic Light-Emitting Diode through Triplet Exciton Reharvesting by Employing Blended Electron Donor and Acceptor as the Emissive Layer.
abstract: A blended bimolecular exciplex formation was demonstrated between two individual donor and acceptor molecules, which are tris(4-carbazoyl-9-ylphenyl)amine (TCTA) and 2,4,6-tris(3'-(pyridin-3-yl)biphenyl-3-yl)-1,3,5-triazine (Tm3PyBPZ). The photoluminescence spectrum of the exciplex in the solid state showed an emission with a peak around 514 nm (∼2.49 eV). By applying this exciplex as an emitting layer, a highly efficient all-fluorescent organic lighting emitting diode with maximum efficiencies of 13.1% and 53.4 lm/W can be realized under an extremely low turn-on voltage of only 2.4 V. The thermally activated delayed fluorescence (TADF) process is believed to be responsible for the excellent device performance.
authors.affiliation: Department of Physics and Institute of Advanced Materials, Hong Kong Baptist University , Kowloon Tong, Hong Kong SAR, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Physics and Institute of Advanced Materials, Hong Kong Baptist University , Kowloon Tong, Hong Kong SAR, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Cai
authors.affiliation: Department of Physics and Institute of Advanced Materials, Hong Kong Baptist University , Kowloon Tong, Hong Kong SAR, China.
authors.forename: King Fai
authors.initials: KF
authors.lastname: Li
authors.affiliation: Department of Physics and Institute of Advanced Materials, Hong Kong Baptist University , Kowloon Tong, Hong Kong SAR, China.
authors.forename: Hoi Lam
authors.initials: HL
authors.lastname: Tam
authors.affiliation: Department of Physics and Institute of Advanced Materials, Hong Kong Baptist University , Kowloon Tong, Hong Kong SAR, China.
authors.forename: Kin Long
authors.initials: KL
authors.lastname: Chan
authors.affiliation: Department of Physics and Institute of Advanced Materials, Hong Kong Baptist University , Kowloon Tong, Hong Kong SAR, China.
authors.forename: Kok Wai
authors.initials: KW
authors.lastname: Cheah
keywords: intermolecular exciplex; organic light-emitting diode (OLED); thermally activated delayed fluorescence (TADF); triplet exciton reharvesting; weak coupled donor and acceptor