Abstract Organic electronics research has focused primarily on flexible, inexpensive versions of traditional semiconductor technologies. Although mixed ionic/electronic conduction in conjugated organic materials introduces exciting functionality, the understanding fundamental processes that take place is still its infancy. In this Research News article, advantages, applications, and basic needs relate to incorporation ionic carriers electronic devices are discussed placed broader context field.

We study electrochemical p- and n-type doping in the well-known light-emitting polymer poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV). Doping reactions are characterized using cyclic voltammetry. Optical measurements including photoluminescence UV/Vis/NIR transmission were performed on doped samples. find that oxidation MEH-PPV is a highly reversible reaction resulting stable freestanding films, while reduced form unstable irreversible. discuss dependence of scan rate,...

We report the synthesis of a soluble perylene-based small molecule for use as an n-type emissive material organic optoelectronic device applications, and demonstrate in light-emitting electrochemical cell configuration.

Single‐component, metal‐free, biocompatible, electromechanical actuator devices are fabricated using a composite material composed of silk fibroin and poly(pyrrole) (PPy). Chemical modification techniques developed to produce free‐standing films with bilayer‐type structure, unmodified on one side an interpenetrating network (IPN) PPy the other. The IPN formed between prohibits delamination, resulting in durable fully biocompatible device. electrochemical stability these materials is...

A p–n junction in an organic emissive polymer is chemically fixed through the use of polymerizable ions. This leads to a permanent configuration compensating ions, unlike dynamic light-emitting electrochemical cells. The process demonstrated with red-, green-, and blue-light-emissive polymers; photovoltaic effect also demonstrated.

We report color-tunable light-emitting devices employing CdSe/ZnS quantum dots (QDs) blended into a polymer electrochemical cell (LEC) architecture. This novel structure circumvents the charge-tunneling barrier of QDs to achieve bright, uniform, and highly voltage-independent electroluminescence, with nearly all emission generated by QDs. By blending varying ratios two QD materials that emit at different wavelengths, we demonstrate precise color control in single layer device structure.

Flexible and conductive biocompatible materials are attractive candidates for a wide range of biomedical applications including implantable electrodes, tissue engineering, controlled drug delivery. Here, we demonstrate that chemical electrochemical polymerization techniques can be combined to create highly versatile silk-conducting polymer (silk-CP) composites with enhanced conductivity stability. Interpenetrating silk-CP were first generated via in situ deposition polypyrrole during...

Here we detail the fabrication and testing of artificial muscles fabricated from composites natural biopolymer silk fibroin conducting polymers. Aligned nanofiber bundles that mimic structure skeletal were produced via electrospinning, fibers infused with polymers using chemical electrochemical in situ polymerization methods. The resulting individual, electroactive underwent electromechanical actuation biologically-relevant electrolyte solutions when low potentials applied, thus mimicking...

We explore the thickness-dependent optical properties of single layer polymer light emitting diodes for two materials, poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-ethenylene-2,5-dioctyloxy-1,4-phenylene-ethenylene] (MEH-DOO-PPV) and poly(2,7-(9,9-bis(2-ethylhexyl))fluorene)-2,7-bis(4-methylphenyl)phenylamine (PF with 2% endcap). compare experimental electroluminescence spectra radiance values as a function emissive thickness simulations utilizing dipole methods within transfer-matrix...

We present a study on the optical and electronic properties of light-emitting electrochemical cells (LECs) based poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) with goal understanding emission profiles characterizing salt electrode dependence. Direct imaging photoluminescence electroluminescence planar LECs simulations interference effects were performed in order to gain insight into vertical structure LECs. While our results are consistent oxidative doping, they imply...

Abstract Polymer photovoltaic devices commonly suffer from low power conversion efficiencies despite the potential for much higher performance. Here we apply a recently reported system creating chemically fixed polymer p‐i‐n junction to devices. Both single‐component and blended donor/acceptor are fabricated tested. We study during charging find that changes in light dark current characteristics consistent with formation of active material. While overall performance these systems need...

Fixed-junction light-emitting electrochemical cells (LECs) using ion-pair monomers (IPMs) have been shown to be promising. Here we present several novel polymerizable ionic liquids that combine the advantages of with fixed-junction functionality IPMs. We show significantly improved performance over earlier IPM-based LECs.

Organic semiconductors have the unique ability to conduct both ionic and electronic charge carriers in thin films, an emerging advantage applications such as light-emitting devices, transistors, electrochromic among others. Evidence suggests that profiles of ions electrochemical doping polymer film during operation significantly impact performance stability device. However, few studies directly characterized ion within LECs. Here, we present in-depth study distributions LECs following...

Biocompatible materials capable of controlled actuation are in high demand for use biomedical applications such as dynamic tissue scaffolding, valves, and steerable surgical tools. Conducting polymer actuators interest because they operate aqueous electrolytes at low voltages can generate stresses similar to natural muscle. Recently, our group has demonstrated a composite material silk poly(pyrrole) (PPy) that is mechanically robust, made from biocompatible materials, bends under an applied...

Ion profiles in polymer light-emitting electrochemical cells are known to significantly affect performance and stability, but not easily measured. Here, secondary ion mass spectrometry is used investigate both dynamic chemically fixed junction devices. Results indicate lower reversibility of junctions a more significant time delay for redistribution than previously expected, confirm the complete immobilization ions When compared with prior studies analyzing electric field similar devices,...

The chemistry of electron deficient π-acceptors offers unique challenges in the rational design and synthesis organic dyes for use solar cells. We have synthesized 2-cyano-2-(3-cyano-4-((E)-4-(dibutylamino)styryl)-5,5-dimethylfuran-2(5H)-ylidene)ethanoic acid (2), a dye containing an carboxylated version strongly withdrawing TCF group by way stepwise isolation 2,5-dihydro-2-imino-4,5,5-trimethylfuran-3-carbonitrile (5), previously only available as intermediate via microwave chemistry. this...

We present a solid state electrochromic device based on poly (phenylene vinylene) light-emitting polymers and explore performance as function of salt type, concentration, polymer layer thickness. Salts employing organic anions display improved optical contrasts. Higher concentrations thicker devices produce higher contrasts at the cost slower switching speeds. Devices high reversibility, dramatic (>40%), low operating voltages (<2V) that are comparable to state-of-the-art...

We study the thermochromic response of poly [2-methoxy-5-(2 -ethylhexyloxy)-1,4-phenylenevinylene] (PPV) gel films. These films undergo a reversible, continuous color change from red to yellow in practically relevant temperature range 25–100°C. show that absorption and photoluminescence continuously decrease blueshift along with an increase both highest occupied molecular orbital lowest unoccupied levels as is increased, this effect does not depend on glass transition temperature....

ABSTRACT Biocompatible actuators that are capable of controlled movement and can function under biologically relevant conditions significant interest for biomedical applications. Previously, we have demonstrated a composite material silk biopolymer the conducting polymer poly(pyrrole) (PPy) be formed into functional bilayer bending actuator. Further, these silk‐PPy composites generate forces comparable to human muscle (>0.1 MPa) making them ideal candidates interfacing with biological...