Efficient Near-Infrared Electroluminescence at 840 nm with “Metal-Free” Small-Molecule:Polymer Blends
Artikel i vetenskaplig tidskrift, 2018

Due to the so-called energy-gap law and aggregation quenching, the efficiency of organic light-emitting diodes (OLEDs) emitting above 800 nm is significantly lower than that of visible ones. Successful exploitation of triplet emission in phosphorescent materials containing heavy metals has been reported, with OLEDs achieving remarkable external quantum efficiencies (EQEs) up to 3.8% (peak wavelength > 800 nm). For OLEDs incorporating fluorescent materials free from heavy or toxic metals, however, we are not aware of any report of EQEs over 1% (again for emission peaking at wavelengths > 800 nm), even for devices leveraging thermally activated delayed fluorescence (TADF). Here, the development of polymer light-emitting diodes (PLEDs) peaking at 840 nm and exhibiting unprecedented EQEs (in excess of 1.15%) and turn-on voltages as low as 1.7 V is reported. These incorporate a novel triazolobenzothiadiazole-based emitter and a novel indacenodithiophene-based transport polymer matrix, affording excellent spectral and transport properties. To the best of knowledge, such values are the best ever reported for electroluminescence at 840 nm with a purely organic and solution-processed active layer, not leveraging triplet-assisted emission.

indacenodithiophene

near-infrared

blends

organic light-emitting diodes (OLEDs)

triazolobenzothiadiazole

Författare

Alessandro Minotto

University College London (UCL)

Petri Henrik Murto

Flinders University

Chalmers, Kemi och kemiteknik, Tillämpad kemi

Zewdneh Genene

Chalmers, Kemi och kemiteknik, Tillämpad kemi

Addis Ababa University

Andrea Zampetti

University College London (UCL)

Giuseppe Carnicella

University College London (UCL)

Wendimagegn Mammo

Addis Ababa University

Mats Andersson

Flinders University

Chalmers, Kemi och kemiteknik, Tillämpad kemi

Ergang Wang

Chalmers, Kemi och kemiteknik, Tillämpad kemi

Franco Cacialli

University College London (UCL)

Advanced Materials

09359648 (ISSN) 15214095 (eISSN)

Vol. 30 34 1706584

Organic Semiconductors for NIR Optoelectronics (OSNIRO)

Europeiska kommissionen (EU) (EC/FP7/607585), 2013-10-01 -- 2017-09-30.

Ämneskategorier

Polymerkemi

Annan kemi

Den kondenserade materiens fysik

DOI

10.1002/adma.201706584

Mer information

Senast uppdaterat

2019-04-03