Impact of the Acceptor Group on the Properties of Triphenylamine-Donor-Acceptor Dyes: An Experimental and Computational Study.

Three triphenylamine-Indane donor-acceptor dyes with different functional groups on the acceptor were studied to investigate how substitution would affect the optical properties. The dyes studied were IndCN, containing two malononitrile groups; InO, with two ketone groups; and InOCN, which features mixed functional groups. A combination of Raman spectroscopy, UV-vis absorption and emission spectroscopy, and density functional theory (DFT) calculations were employed for characterization.

A PEDOT based graft copolymer with enhanced electronic stability.

Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) remains the most investigated conjugated polymer in bioelectronics, due to its biocompatibility, high conductivity, and commercial availability. Despite these advantages, it suffers from structural and electronic instability, associated with the PSS component. Here, a graft copolymer based on ionised sulfonic modified PEDOT, poly(EDOTS--EDOT), was electrochemically synthesised with demonstrated structural and electronic stability and enhanced electrochemical performance.

Organic Mixed Ionic-Electronic Conductors Based on Tunable and Functional Poly(3,4-ethylenedioxythiophene) Copolymers.

Organic mixed ionic-electronic conductors (OMIECs) are being explored in applications such as bioelectronics, biosensors, energy conversion and storage, and optoelectronics. OMIECs are largely composed of conjugated polymers that couple ionic and electronic transport in their structure as well as synthetic flexibility. Despite extensive research, previous studies have mainly focused on either enhancing ion conduction or enabling synthetic modification.

A Novel Cryogenic Approach to 3D Printing Cytocompatible, Conductive, Hydrogel-Based Inks.

In the field of tissue engineering and regenerative medicine, developing cytocompatible 3D conductive scaffolds that mimic the native extracellular matrix is crucial for the engineering of excitable cells and tissues. In this study, a custom cryogenic extrusion 3D printer was developed, which afforded control over both the ink and printing surface temperatures. Using this approach, aqueous inks were printed into well-defined layers with high precision.

Edge-Functionalized Graphene/Polydimethylsiloxane Composite Films for Flexible Neural Cuff Electrodes.

The design of neural electrodes has changed in the past decade, driven mainly by the development of new materials that open the possibility of manufacturing electrodes with adaptable mechanical properties and promising electrical properties. In this paper, we report on the mechanical and electrochemical properties of a polydimethylsiloxane (PDMS) composite with edge-functionalized graphene (EFG) and demonstrate its potential for use in neural implants with the fabrication of a novel neural cuff electrode. We have shown that a 200 μm thick 1:1 EFG/PDMS composite film has a stretchability of up to 20%, a Young's modulus of 2.

Cu-THQ-EFG Composite for Highly Selective Electrochemical CO Reduction to Formate at Low Overpotentials.

Metal organic framework (MOFs) are promising materials for electrocatalysis. However, the active sites of bulk MOFs crystal normally cannot be fully utilized because of the slow reagent penetration of pores and blockage of active sites. Herein, we report a facile way to deposit copper-benzoquinoid (Cu-THQ) on the edge-functionalized graphene (EFG) which prevented material's aggregation.

Exohedral Functionalization of Fullerene by Substituents Controlling of Molecular Organization for Spontaneous C Dimerization in Liquid Crystal Solutions and in a Bulk Controlled by a Potential.

A study was carried out on the possibility of orderly and spontaneous dimerization at room temperature of C cages in fullerene liquid crystal fullerene dyads (R-C). For this purpose, dyads with a structural elements feature supporting π-stacking and Van der Waals interactions were tested, due to the presence of terthiophene donors linked through an α-position or dodecyloxy chains. In addition, this possibility was also tested and compared to dyads with shorter substituents and the pristine C.

Electrochemical and Spectroelectrochemical Studies on the Reactivity of Perimidine-Carbazole-Thiophene Monomers towards the Formation of Multidimensional Macromolecules versus Stable π-Dimeric States.

During research on cross-linked conducting polymers, double-functionalized monomers were synthesized. Two subunits potentially able to undergo oxidative coupling were used-perimidine and, respectively, carbazole, 3,6-di(hexylthiophene)carbazole or 3,6-di(decyloxythiophene)carbazole; alkyl and alkoxy chains as groups supporting molecular ordering and 14-benzo[4,5]isoquinone[2,1-a]perimidin-14-one segment promoting CH⋯O interactions and π-π stacking. Electrochemical, spectroelectrochemical, and density functional theory (DFT) studies have shown that potential-controlled oxidation enables polarization of a specific monomer subunit, thus allowing for simultaneous coupling via perimidine and/or carbazole, but mainly leading to dimer formation.

Amphiphilic Zinc Porphyrin Single-Walled Carbon Nanotube Hybrids: Efficient Formation and Excited State Charge Transfer Studies.

Herein, the microscopic and spectroscopic characterization of a novel non-covalent electron donor-acceptor system, in which three different metalloporphyrins (1, 2, and 3) play the dual role of light harvester and electron donor with SWCNTs as electron acceptor, is described. To this end, microscopy, that is, atomic force microscopy (AFM) and transmission electron microscopy (TEM) corroborate the formation of 1-SWCNT, 2-SWCNT, and 3-SWCNT. Spectroscopy by means of Raman, fluorescence, and transient absorption spectroscopy confirmed efficient charge-transfer interaction from photoexcited metalloporphyrins to SWCNTs in the ground and excited state of 1-SWCNT, 2-SWCNT, and 3-SWCNT.

Investigation of Ferrocene Linkers in β-Substituted Porphyrins.

A series of β-ferrocene-modified zinc porphyrins, with various electron-withdrawing units appended to the ferrocene, were synthesized, and their electronic properties were investigated. The ferrocene was able to be modified with the substituents, with its oxidation potential increased by up to 0.3 V, without significantly perturbing the porphyrin core.

Optimizing Electron Densities of Ni-N-C Complexes by Hybrid Coordination for Efficient Electrocatalytic CO Reduction.

Metal-N-C is a type of attractive electrocatalyst for efficient CO reduction to CO. Because of the ambiguity in their atomic structures, the active sites and catalytic mechanisms of the catalysts have remained under debate. Here, the effects of N and C hybrid coordination on the activity of Ni-N-C catalysts were investigated, combining theoretical and experimental methods.

Self-Healing Electrode with High Electrical Conductivity and Mechanical Strength for Artificial Electronic Skin.

A self-healing electrode is an electrical conductor that can repair internal damage by itself, similar to human skin. Since self-healing electrodes are based on polymers and hydrogels, these components are still limited by low electrical conductivity and mechanical strength. In this study, we designed an electrically conductive, mechanically strong, and printable self-healing electrode using liquid crystal graphene oxide (LCGO) and silver nanowires (AgNWs).

Dual Droplet Functionality: Phototaxis and Photopolymerization.

The use of phototaxis to move droplets in liquids offers the opportunity to emulate natural processes such as the controlled transport of materials in fluidic environments and to undertake chemistry at specific locations. We have developed a photoactive organic droplet, whose movement in aqueous solution is driven by a photoinitiator, as a result of a light-induced reaction within the droplet generating a Marangoni flow. The photoinitiator not only drives the droplet motion but can also be used to initiate polymerization following transfer of the droplet to a specific location and its merging with a monomer-containing droplet.

Bio-Inspired Stretchable and Contractible Tough Fiber by the Hybridization of GO/MWNT/Polyurethane.

Spider silks represent stretchable and contractible fibers with high toughness. Those tough fibers with stretchability and contractibility are attractive as energy absorption materials, and they are needed for wearable applications, artificial muscles, and soft robotics. Although carbon-based materials and poly(vinyl alcohol) (PVA) composite fibers exhibit high toughness, they are still limited in low extensibility and an inability to operate in the wet-state condition.

When "Donor-Acceptor" Dyes Delocalize: A Spectroscopic and Computational Study of D-A Dyes Using "Michler's Base".

In this study, we show that the "Michler's base" motif can be combined in a donor-acceptor arrangement with a range of acceptor units (indandione, indandione with cyano substituents, barbituric acid, or rhodanine) to give photophysical properties that are dominated by delocalized excited states. By changing the acceptor unit and by altering the planarity of this system, it is possible to tune the low-energy absorption feature in terms of intensity from 23 000 to 67 000 M cm and energy between 500 and 700 nm. Resonance Raman spectroscopy and time-dependent density functional theory indicate that this absorption feature has two underlying transitions: a weaker charge-transfer transition around 500 nm and a strong mixed or delocalized transition between 550 and 700 nm.

Publisher Correction: Room temperature CO reduction to solid carbon species on liquid metals featuring atomically thin ceria interfaces.

The original version of this Article contained errors in the author affiliations. Affiliation 1 incorrectly read 'School of Chemical Engineering, University of New South Wales (UNSW), Sydney, NSW 2031, Australia' and affiliation 4 incorrectly read 'School of Engineering, RMIT University, Melbourne, VIC 3001, Australia.' This has now been corrected in both the PDF and HTML versions of the Article.

Room temperature CO reduction to solid carbon species on liquid metals featuring atomically thin ceria interfaces.

Negative carbon emission technologies are critical for ensuring a future stable climate. However, the gaseous state of CO does render the indefinite storage of this greenhouse gas challenging. Herein, we created a liquid metal electrocatalyst that contains metallic elemental cerium nanoparticles, which facilitates the electrochemical reduction of CO to layered solid carbonaceous species, at a low onset potential of -310 mV vs CO/C.

Silicon as a ubiquitous contaminant in graphene derivatives with significant impact on device performance.

Silicon-based impurities are ubiquitous in natural graphite. However, their role as a contaminant in exfoliated graphene and their influence on devices have been overlooked. Herein atomic resolution microscopy is used to highlight the existence of silicon-based contamination on various solution-processed graphene.

Efficient and Stable Solid-State Dye-Sensitized Solar Cells by the Combination of Phosphonium Organic Ionic Plastic Crystals with Silica.

Remarkably efficient quasi-solid-state dye-sensitized solar cells (DSSCs) have been fabricated using organic ionic plastic crystal electrolytes based on a small triethyl(methyl)phosphonium [P] cation and two types of sulfonamide anions, bis(fluorosulfonyl)amide (FSA) and bis(trifluoromethanesulfonyl)amide (TFSA), in combination with varying amounts of silica (SiO). Solar cell efficiencies of up to 7.4% were obtained, which is comparable to our benchmark efficiencies of liquid (acetonitrile) electrolyte-based devices.

Moving Droplets in 3D Using Light.

The emulation of the complex cellular and bacterial vesicles used to transport materials through fluids has the potential to add revolutionary capabilities to fluidic platforms. Although a number of artificial motile vesicles or microdroplets have been demonstrated previously, control over their movement in liquid in 3D has not been achieved. Here it is shown that by adding a chemical "fuel," a photoactive material, to the droplet, it can be moved in any direction (3D) in water using simple light sources without the need for additives in the water.

Computational and Spectroscopic Analysis of β-Indandione Modified Zinc Porphyrins.

Porphyrins have characteristic optical properties which give them the potential to be used in a range of applications. In this study, a series of β-indandione modified zinc porphyrins, systematically changed in terms of linker length and substituent, resulted in absorption spectra that are dramatically different than that observed for the parent zinc porphyrin (ZnTXP, 5,10,15,20-tetrakis(3,5-dimethylphenyl)porphyrinato zinc(II)). These changes include strong absorptions at 420, 541, and 681 nm (110.

Fabrication of 3D structures from graphene-based biocomposites.

With the advancement of new material technologies and the invention of new techniques such as 3D printing over recent decades, the fabrication of more complex and versatile structures from biocomposites can now be easily achieved. Graphenic fillers are being increasingly used to improve and tune the electrical conductivity and mechanical properties of biodegradable/biocompatible polymers thus opening the way for the fabrication of biocomposite structures critical for areas such as tissue engineering. This review provides an overview of recent work on the fabrication of structures using graphene-based biocomposites, which provide constructs with properties better tailored to a variety of biomedical applications.

Design and engineering of water-soluble light-harvesting protein maquettes.

Natural selection in photosynthesis has engineered tetrapyrrole based, nanometer scale, light harvesting and energy capture in light-induced charge separation. By designing and creating nanometer scale artificial light harvesting and charge separating proteins, we have the opportunity to reengineer and overcome the limitations of natural selection to extend energy capture to new wavelengths and to tailor efficient systems that better meet human as opposed to cellular energetic needs. While tetrapyrrole cofactor incorporation in natural proteins is complex and often assisted by accessory proteins for cofactor transport and insertion, artificial protein functionalization relies on a practical understanding of the basic physical chemistry of protein and cofactors that drive nanometer scale self-assembly.