Binuclear cyclometalated Ir(III) complexes with bis-bidentate butterfly-shaped ligands: synthesis, characterization, and application in efficient yellow-orange light-emitting electrochemical cells.

Two yellow-to-orange-emitting binuclear iridium complexes of the form [Ir(ppy)(N^N)](ClO) (namely IrL1 and IrL2) were designed and synthesized, using phenylpyridine (ppy) as a cyclometalating ligand (C^N) and phenanthroimidazole-based bridging compounds as ancillary ligands (N^N), to explore the effect of sterically hindered bulky bridging ligands and their substituents on the electronic and emission properties of the related ionic transition metal complexes (iTMCs) and the performance of iTMC-based light-emitting electrochemical cells (iTMC-LECs). In CHCl solution, complexes IrL1 and IrL2 afford yellow-to-orange emission centered at 570 and 582 nm with PLQYs of 27% and 36%, respectively. The reversible and quasi-reversible redox behaviors of both complexes are shown to reveal the excellent stability of the emitters in solution.

Unveiling the key role of metal coordination mode and ligand's side groups on the performance of deep-red light-emitting electrochemical cell.

Three novel deep-red to near-infrared (DR to NIR) emitters based on mononuclear and dinuclear ruthenium(II) complexes with bulky structures were presented herein. For the first time, the unusual effects of metal coordination mode on the electroluminescence properties of a binuclear emitter were investigated. Unexpectedly, the mononuclear complexes showed superior performance in deep-red light-emitting electrochemical cells (DR-LEC) compared to the dinuclear complex.

Phenanthroimidazole as molecularly engineered switch for efficient and highly long-lived light-emitting electrochemical cell.

Light-emitting electrochemical cells (LECs) based on Ir(III) complexes owing to the superior advantages exhibit high potential for display and lighting applications. Herein, a series of Ir(III) complexes based on phenanthroimidazole (PI) as an ancillary ligand were synthesized to achieve efficient and highly stable yellow-to-orange LEC devices with fast response. These complexes exhibit appropriate electrochemical stability and significant suppression of concentration quenching in the thin films compared to the archetype complex.

New molecularly engineered binuclear ruthenium(II) complexes for highly efficient near-infrared light-emitting electrochemical cells (NIR-LECs).

From the practical point of view, the stability, response time and efficiency of near-infrared light-emitting electrochemical cells (NIR-LECs) are key factors. By using the high potential of chemical modification potential of the phenanthroimidazole ligand, three new binuclear ruthenium(II) complexes with an alkyl spacer as the NIR-emitter were designed and synthesized. NIR-LECs based on these complexes exhibit near-infrared emission at the maximum wavelength of up to 705 nm and with an EQE of up to 0.

High-Efficiency Deep-Red Light-Emitting Electrochemical Cell Based on a Trinuclear Ruthenium(II)-Silver(I) Complex.

Turn-on time is a key factor for lighting devices to be of practical application. To decrease the turn-on time value of a deep-red light-emitting electrochemical cells (DR-LECs), two novel approaches based on molecularly engineered ruthenium phenanthroimidazole complexes were introduced. First, we found that with the incorporation of ionic methylpyridinium group to phenanthroimidazole ligand, the turn-on time of the DR-LECs device was dramatically reduced, from 79 to 27 s.

Molecularly engineered electroplex emission for an efficient near-infrared light-emitting electrochemical cell (NIR-LEC).

Electroplex emission is rarely seen in ruthenium polypyridyl complexes, and there have been no reports from light-emitting electrochemical cells (LECs) to date. Here, for the first time, near-infrared (NIR) emission the electroplex mechanism in a LEC based on a new blend of ruthenium polypyridyl complexes is described. The key factor in the design of the new complexes is the 0.

Low-Turn-On-Voltage, High-Brightness, and Deep-Red Light-Emitting Electrochemical Cell Based on a New Blend of [Ru(bpy)] and Zn-Diphenylcarbazone.

Deep red light-emitting electrochemical cells were prepared based on a blend of [Ru(bpy)], a cationic complex, and a neutral Zn(II)-complex based on diphenylcarbazone ligands, named Zn(DPCO). The crystal structure of the Zn(DPCO) (bpy)] molecule revealed that the DPCO ligand has been deprotonated to form DPCO and coordinated to the Zn center metal through the C=O and N=N moieties of DPCO. From the cyclic voltammetry results and controlled potential coulometry data of the diphenylcarbazide (DPC) ligand, it is possible to establish that DPC is oxidized in an irreversible process at +0.

A near infrared light emitting electrochemical cell with a 2.3 V turn-on voltage.

We report on an organic electroluminescent device with simplified geometry and emission in the red to near infrared (NIR) spectral region which, has the lowest turn-on voltage value, 2.3 V, among light emitting electrochemical cells (LEECs). We have synthesized and characterized three novel ruthenium π-extended phenanthroimidazoles which differ on their N^N ligands.

On how ancillary ligand substitution affects the charge carrier dynamics in dye-sensitized solar cells.

With respect to N3, a champion sensitizer in dye-sensitized solar cells (DSSCs), S3 which contained a phenTz (1,10-phenanthroline 5-tetrazole) ancillary ligand showed outstanding improvements in molar extinction coefficient () from 10 681.8 to 12 954.5 M cm as well as 0.

Efficient near infrared light emitting electrochemical cell (NIR-LEEC) based on new binuclear ruthenium phenanthroimidazole exhibiting desired charge carrier dynamics.

Near-infrared light-emitting electrochemical cell (NIR-LEEC) has emerged as a new and promising lighting sourcewhich could serve as low-cost alternatives in NIR light-emitting sources which are typically expensive. LECs were also shown advantages such as light weight, simplicity and low operation voltages. However, only a few examples of NIR-LEEC are reported in which external quantum efficiency(EQE) of devices limited to 0.

Low-voltage, high-brightness and deep-red light-emitting electrochemical cells (LECs) based on new ruthenium(ii) phenanthroimidazole complexes.

Light-Emitting Electrochemical Cells (LECs) with a simple device structure ITO/Ru complex/Ga:In were prepared by using heteroleptic ruthenium(ii) complexes containing 2-(2-hydroxyphenyl)-1-(4-bromophenyl)-1h-imidazo[4,5-f][1,10]phenanthroline (hpbpip) as the π-extended ligand. After ancillary ligand modification, the [Ru(hpbpip)(dmbpy)2](ClO4)2 complex shows a deep red electroluminescence emission (2250 cd m(-2) at 6 V) centered at 685 nm, 65 nm red-shifted compared to the [Ru(bpy)3](ClO4)2 benchmark red-emitter at a very low turn voltage (2.6 V), demonstrating its potential for low-cost deep-red light sources.