Orange electrophosphorescence based on bis(3,5-dimethylphenyl)pyridine iridium (III) complexes for non-halogenated solution processable phosphorescent organic light-emitting diodes

Inkjet Printing of Mixed-Host Emitting Layer for Electrophosphorescent Organic Light-Emitting Diodes

“…For a mixture of two HT-type molecules, TCTA and 4,4′-cyclohexylidenebis­[ N , N -bis­(4-methylphenyl)­benzenamine] (TAPC), a slightly lower CE of 32.0 cd/A was obtained when doped with FIrpic . Our device did not quite match the high level of EQE and CE of 18% and 57.5 cd/A, respectively, reported for the same host mixture (TCTA/3CzPFP) in an orange-emitting device. Efficiency roll-off, however, was higher in Hwang’s device at low (5%) dopant concentration and in a similar range at high (15%) dopant concentration, compared to our devices.…”

“…We found that the best overall outcome in terms of both luminance and efficiency roll-off was achieved at a host ratio of 60:40, which can be explained as the result of improved charge balance because of the addition of 3CzPFP. 28,29 Layer morphology and roughness also improved in the mixed host in comparison to the pristine host (100% TCTA) and cohost (100% 3CzPFP), as indicated by Figure 3d−f. When 3CzPFP (triplet energy of 2.82 eV) was added as the cohost, two desirable effects were observed.…”

“…27 For an orange-emitting PhOLED device with a mixed host of TCTA and 3CzPFP, an EQE and CE of 18% and 57.5 cd/A, respectively, were reported. 28 Even higher efficiency (above 30%) was obtained with 3CzPFP as the host of a green thermally activated delayed fluorescence emitting material. 29 As a patterning technique for the EML in large-area PhOLED displays, DOD inkjet printing is potentially attractive.…”

“…Furopyridine derivatives such as 3-(3-(carbazole-9-yl)­phenyl)­pyrido­[3′,2′:4,5]­furo­[2,3- b ]­pyridine (3CzPFP) come into consideration in this context because they possess a highly electron deficient core structure . For an orange-emitting PhOLED device with a mixed host of TCTA and 3CzPFP, an EQE and CE of 18% and 57.5 cd/A, respectively, were reported . Even higher efficiency (above 30%) was obtained with 3CzPFP as the host of a green thermally activated delayed fluorescence emitting material …”

The nonlinear optics property of heterodinuclear (Li and Na) sexipyridine helix: A density functional theory study

“…[ 25,26 ] Thus, pyridine transition metal complexes have a rich literature, and they are applied as a chromophore, catalyst, thermal reaction battery, semiconducting material, and so on. [ 27–30 ] In addition, because of excellent coordination capability, it was easy to obtain different topological structures containing single, double, or even triple helices, knots, and so on by spontaneous organization. [ 31–36 ] For instance, poly‐ethynylpyridine could form helical complexes with saccharides, [ 37 ] glycosyl template, [ 38 ] or transition metal.…”