Binary Solvent Effects on Thermally Crosslinked Small Molecular Thin Films for Solution Processed Organic Light-Emitting Diodes

ABSTRACTWe describe the fabrication and characterization of solution processed organic light emitting diodes (OLEDs) based on novel near-infrared emitting erbium(III) complexes, consisting of three perfluoroalkyl-β-diketone ligands and 5-NO2-1,10-phenanthroline as chelating N,N-donor molecule. The function of N,N molecule is to saturate the coordination sphere of the erbium ion and to harvest excitation light that can be transferred to the excited states of the erbium ion. The devices have been fabricated by spin-coating, using 1 %wt methanol precursor solutions. These Er-complexes form very uniform thin films. The OLED structure is glass/indium–tin oxide(ITO) / poly(3,4-ethylenedioxythiophene) / poly(4-styrenesulfonate) (PEDOT:PSS)/Er-complex/Ca/Al. The good electrical response, with low threshold voltages (a few volts), together with the very uniform thin films formed, made these complexes promising for IR emitting displays.

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Room-Temperature Sol–Gel Derived Molybdenum Oxide Thin Films for Efficient and Stable Solution-Processed Organic Light-Emitting Diodes

ACS Applied Materials & Interfaces ◽

10.1021/am4007319 ◽

2013 ◽

Vol 5 (13) ◽

pp. 6024-6029 ◽

Cited By ~ 43

Author(s):

Qiang Fu ◽

Jiangshan Chen ◽

Changsheng Shi ◽

Dongge Ma

Keyword(s):

Thin Films ◽

Molybdenum Oxide ◽

Room Temperature ◽

Light Emitting Diodes ◽

Sol Gel ◽

Stable Solution ◽

Organic Light Emitting Diodes ◽

Solution Processed ◽

Light Emitting ◽

Organic Light

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Solution-Processed Efficient Blue Phosphorescent Organic Light-Emitting Diodes (PHOLEDs) Enabled by Hole-Transport Material Incorporated Single Emission Layer

Materials ◽

10.3390/ma14030554 ◽

2021 ◽

Vol 14 (3) ◽

pp. 554

Author(s):

Taeshik Earmme

Keyword(s):

Light Emitting Diodes ◽

Blue Emission ◽

Hole Transport ◽

Organic Light Emitting Diodes ◽

Emission Layer ◽

Solution Processed ◽

Light Emitting ◽

Organic Light ◽

Single Emission ◽

Blue Phosphorescent

Solution-processed blue phosphorescent organic light-emitting diodes (PHOLEDs) based on a single emission layer with small-molecule hole-transport materials (HTMs) are demonstrated. Various HTMs have been readily incorporated by solution-processing to enhance hole-transport properties of the polymer-based emission layer. Poly(N-vinylcarbazole) (PVK)-based blue emission layer with iridium(III) bis(4,6-(di-fluorophenyl)pyridinato-N,C2′)picolinate (FIrpic) triplet emitter blended with solution-processed 1,1-bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC) gave luminous efficiency of 21.1 cd/A at a brightness of 6220 cd/m2 with an external quantum efficiency (EQE) of 10.6%. Blue PHOLEDs with solution-incorporated HTMs turned out to be 50% more efficient compared to the reference device without HTMs. The high hole mobility, high triplet energy of HTM, and favorable energy transfer between HTM blended PVK host and FIrpic blue dopant were found to be important factors for achieving high device performance. The results are instructive to design and/or select proper hole-transport materials in solution-processed single emission layer.

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