Light-emitting electrochemical cells (LECs) are fabricated by gravure printing. The compromise between device performance and printing quality is correlated to the ink formulation process. It shown that rheological properties of formulations LECs can be tailored without changing chemical composition material blend. As a service our authors readers, this journal provides supporting information supplied authors. Such materials peer reviewed may re-organized for online delivery, but not...

The synthesis and characterization of soluble azaiptycenes is reported. Optical physical properties were studied compared with those the structurally consanguine azaacenes. Electrochemical experiments quantum-chemical calculations revealed electronic structure iptycene derivatives. Their crystallization behavior was examined. A highly fluorescent amorphous diazatetracene derivative integrated into a simple organic light-emitting diode, showing enhanced performance that previously reported,...

We study two types of water/alcohol-soluble aliphatic amines, polyethylenimine (PEI) and polyethylenimine-ethoxylated (PEIE), for their suitability as electron injection layers in solution-processed blue fluorescent organic light-emitting diodes (OLEDs). X-ray photoelectron spectroscopy is used to determine the nominal thickness polymer while ultraviolet carried out induced work-function change silver cathode. The determined shifts are high 1.5 eV PEI 1.3 PEIE. Furthermore, atomic force...

Tetracyanoquinodimethane (TCNQ) was exposed to sodium vapour resulting in three phases containing reduced TCNQ with different electronic structures and chemical compositions.

In this work, we investigate the performance and operational stability of solution-processed organic light-emitting diodes (OLEDs), which comprise polyethylenimine (PEI) as an electron injection layer (EIL). We show that primary degradation mechanism in these OLEDs depends on cathode metal is used contact with EIL. case Al, deterioration OLED during electrical driving mainly caused by excitons reach subsequently degrade emitter/PEI interface. contrast, Ag, device occurs due to additional...

We crosslink an amino-functionalized polyfluorene by the solvent additive 1,8-diiodooctane (DIO).

We report the synthesis of cinnamic acid-functionalized conjugated polymers, which are cross-linked via [2 + 2] cycloaddition by UV illumination, reducing their solubility. The cross-linking reaction was investigated a combination FTIR and optical spectroscopy, an optimum condition for solubility modulation thin films, major challenge in solution-phase fabrication layered optoelectronic devices, reached. As proof concept, OLEDs were fabricated, using these polymers as emissive layers.

In this work, we present organic light-emitting diodes (OLEDs) utilizing a novel amidoamine-functionalized polyfluorene (PFCON-C) as an electron injection layer (EIL). PFCON-C consists of backbone to which multiple tertiary amine side chains are connected via amide group. The influence molecular characteristics on electronic performance and morphological properties was tested compared that the widely used, literature known amino-functionalized (PFN) polyethylenimine (PEI). reduces turn-on...

Herein we present a solution-processed hybrid device architecture combining organic light-emitting diodes (OLEDs) and electrochemical cells (LECs) in bilayer architecture. The LEC interlayer promotes the charge injection from an air-stable Ag cathode as well permits color tuning of emission. To this end, used alcohol-soluble anionic polyfluorene derivative, properties which were investigated by absorption photoluminescence spectroscopy cyclic voltammetry. exhibited operating voltages ∼6 V...

Here we describe the use of a polymer zwitterion as solution-processable material that serves key component electron injection layer (EIL) in solution processed organic light-emitting diodes (OLEDs). Poly(sulfobetaine methacrylate) (PSBMA) was employed both regular and inverted device configurations work-function modifier for Al ZnO cathodes, respectively. For architectures, PSBMA significantly improved OLED performance when compared to reference devices without EIL terms turn-on voltage...

Flat and homogeneous films by ink jet printing of organic materials are proven to be essential for OLED application. The impact formulation, film thickness, pixel size, bank layout process conditions (i.e. drying parameters) have been investigated. Their severe on device performance is illustrated.

We investigate three amine-based polymers, polyethylenimine and two amino-functionalized polyfluorenes, as electron injection layers (EILs) in organic light-emitting diodes (OLEDs) find correlations between the molecular structure of electronic alignment at emitter/EIL interface, resulting device performance. X-ray photoelectron spectroscopy measurements interface indicate that all EIL polymers induce an upward shift Fermi level emitting layer close to similar n-type doping. The absolute...

Inkjet printing (IJP) is on the rise to become a competitive production technology for organic light emitting diodes (OLEDs). Recent progress in with drop volumes down pL regime as well constant performance improvements from material point of view have opened way towards IT displays. Here target resolutions are 250 ppi and beyond. For this purpose, small molecules highly suitable due their low impact ink viscosity excellent device performance. Their current status reviewed based bottom top...

This article reviews the current performance of inkjet printed OLEDs. Recent progress on crucial parameter blue sub‐pixel lifetime is shown, achieved by improving stability emissive material. By adjusting charge balance towards highest efficiency, an external quantum efficiency 11% can be achieved. Further also illustrated for red devices. Within latest R&D type material, a significant increase observed improvement horizontal orientation Prospectively, this will close gap between evaporated and

Abstract Experimental and theoretic approaches will allow for new understandings that are essential to develop OLED materials enable next‐generation displays.

In this article, we review recent developments of modern host materials for green phosphorescent OLEDs. We show that optical emitter orientation can be enhanced significantly by tailored hosts, resulting in an increased device efficiency. Beyond efficiency, matching the system to applied is shown key optimum performance. addition maximized classical performance parameters, hosts need fulfill further requirements. Prominent examples are tuning OLED stack capacitance or development stable...

Recently deuteration has become a key technology for enhancing lifetime of OLED materials without affecting other performance parameters like efficiency and voltage. Over the past years, we intensively investigated impact degree pattern on device performance. The focus our investigation was triplet matrix (TMMs) in emissive layer electron‐blocking (EBL). In this paper, will discuss various aspects materials: from driving further improvements to scale‐up processes.

Organic light emitting diodes (OLEDs) have opened whole new dimensions in the display and lighting industries. They are extremely thin lightweight, and, especially OLED displays, provide perfect images from every viewing angle – with extraordinary color brilliance very high contrast.