By use of the organolanthanide catalysts Me2Si(C5Me4)(NAr)Lu(CH2SiMe3)(THF) and (C5Me5)2LaCH(SiMe3)2, carbazole-substituted phenyl enynes (Z)-CPEY and (E)-CPEY were synthesized, respectively, with excellent regio- and stereoselectivity through the catalytic dimerization of the corresponding terminal alkyne. These new pi-conjugated compounds, in particular, the (E)-enyne isomer (E)-CPEY, act as an excellent single-emitting component for white organic light-emitting devices (WOLEDs), as a result of combination of the blue emission from an isolated molecule with the longer-wavelength emissions (green and orange-red) from excimers. The (E)-CPEY-based double-layer device emitted almost pure white light with CIE coordinates of (0.32, 0.33), maximum brightness of 1395 cd m-2, and maximum current efficiency of 2.07 cd A-1. This is perhaps the purest white emission ever reported for a single-emitting-component WOLED. The quality of the white emission remained almost unchanged under varying driving voltages, demonstrating an advantageous potential of single-emitting-component WOLEDs.

The design and synthesis of highly efficient deep red (DR) and near-infrared (NIR) organic emitting materials with characteristic of thermally activated delayed fluorescence (TADF) still remains a great challenge. A strategy was developed to construct TADF organic solid films with strong DR or NIR emission feature. The triphenylamine (TPA) and quinoxaline-6,7-dicarbonitrile (QCN) were employed as electron donor (D) and acceptor (A), respectively, to synthesize a TADF compound, TPA-QCN. The TPA-QCN molecule with orange-red emission in solution was employed as a dopant to prepare DR and NIR luminescent solid thin films. The high doped concentration and neat films exhibited efficient DR and NIR emissions, respectively. The highly efficient DR and NIR organic light-emitting devices (OLEDs) were fabricated by regulating TPA-QCN dopant concentration in the emitting layers.

A series of wide-bandgap (WBG) copolymers with different alkyl side chains are synthesized. Among them, copolymer PBT1-EH with moderatly bulky side chains on the acceptor unit shows the best photovoltaic performance with power conversion efficiency over 10%. The results suggest that the alkyl side-chain engineering is an effective strategy to further tuning the optoelectronic properties of WBG copolymers.

Highly efficient, low driving-voltage, and emitter concentration insensitive phosphorescent EL devices are established for the first time by using an amidinate-ligated iridium(III) complex as an emitting component.

A new bifunctional NTB (tris(benzimidazol-2-ylmethyl)amine)-type ligand incorporating coordination discriminable tripodal benzimidazolyl and monodentate pyridyl groups, tris((pyridin-3-ylmethyl)benzoimidazol-2-ylmethyl)amine (3-TPyMNTB), has been prepared to assemble 4d–4f heterometallic three-dimensional metal–organic frameworks (MOFs) in a stepwise route: (1) direct reaction of 3-TPyMNTB with Ln(ClO4)3 affords monomeric complexes [Eu(3-TPyMNTB)2](ClO4)3·2.5MeCN (1-Eu) and [Gd(3-TPyMNTB)2](ClO4)3·2MeCN·2CHCl3 (1-Gd), and (2) assembly of the precursors 1-Eu and 1- Gd with AgClO4 gives rise to infinite MOFs [EuAg3(3-TPyMNTB)2(H2O)(MeCN)](ClO4)6·4MeCN (2-Eu-Ag) and [GdAg3(3-TPyMNTB)2(H2O)(MeCN)](ClO4)6·4MeCN (2-Gd-Ag), respectively. In monomer 1-Eu, the ligand shows an antenna effect to transfer absorbed energy to Eu3+ center to emit characteristic red luminescence, while in 4d–4f heterometallic MOF 2-Eu-Ag, the ligand centered emission is resensitized by Ag+ ions to generate dual emissions, coming up with the direct white-light emission from a single crystal. The detailed photoluminescent study has been carried out in both solid state and solution to elucidate the emission nature.

High‐efficiency near‐infrared (NIR) phosphorescent emitter is still a great challenge in solution processable organic light‐emitting diodes (OLEDs). Herein, four novel NIR‐emitting iridium(III) complexes with core–shell structure, named as Ir1, Ir2, Ir3, and Ir4, are rationally designed and synthesized, in which the highly rigid dibenzo[a,c] phenazine (DBPz) moiety is used as coordinated core and the flexible hexyl‐thienyl or 4‐(N,N‐diphenylamino)phenyl as peripheral shell anchored in 3, 6‐, or 11, 12‐positions of DBPz. The influence of the core–shell structure on molecular aggregation, photophysical properties, and electroluminescent (EL) performance is systematically investigated. It is found that core–shell structure and substituted positions of shells have great influences on properties of iridium(III) complexes. Intense NIR emissions at 710–740 nm are observed with luminescent quantum yields of 18–30% in these complexes. Solution‐processed NIR‐OLEDs based on Ir3 or Ir4 show better electroluminescent properties. The maximum external quantum efficiency of 13.72% with a radiance of 26 996 mW Sr−1 m−2 (@708 nm) is obtained in Ir3‐doped OLEDs, representing the state‐of‐the‐art EL performance in the iridium complex‐based NIR‐OLEDs. This work demonstrates that administrating π–π conjugation effects of core–shell structure in C^N ligand is a new avenue to obtain high‐efficiency NIR‐emitting iridium(III) complexes.

A novel blue luminescent chelate complex Bepp 2 (pp ) 2-(2-hydroxyphenyl)pyridine) was synthesized as an electroluminescent material. The single-crystal X-ray diffraction study showed that there are intermolecular π‚ ‚‚π interactions in the solid state of Bepp 2 . This structural character can facilitate charge transport ability. The photoluminescence and electroluminescence properties of Bepp 2 were characterized. Bepp 2 exhibits very strong photoluminescence at 440 nm in chloroform solution. Its PL quantum yield is 80% higher than that of Alq 3 in solution. In this paper we report that Bepp 2 can be used as an emitting material to fabricate blue light electroluminescent devices. The devices with the configuration of [ITO/Cu-Pc/TPD/Bepp 2 /LiF/Al] show electroluminescent efficiency up to 0.55 lm/W. Bepp 2 shows blue EL emission centered at 450 nm. We also demonstrated that Bepp 2 can be used as host material to prepare orange-red EL devices. For the devices of [ITO/TPD/DCM (2wt %) doped Bepp 2 /Al], orange-red color light was observed.

. (2013) 'New oxazoline-and thiazoline-containing heteroleptic iridium(III) complexes for highly-ecient phosphorescent organic light-emitting devices (PhOLEDs) : colour tuning by varying the electroluminescence bandwidth.', Journal of materials chemistry C., 1 (41). pp. 6800-6806.Further information on publisher's website:http://dx.doi.org/10.1039/c3tc31463dPublisher's copyright statement:Additional information: Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details.