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A unique red-emitting molecular rotor for high-fidelity visualizing and long-term tracking mitochondria. [Display omitted] • The rotor property of SQ makes it embed into phospholipid bilayers. • SQ could stain mitochondria without being affected by mitochondrial membrane. • SQ could track and long-term visualize mitochondria in living cells and tissues. • SQ could be applied to track the mitophagy behavior in situ and real-time. Visualizing and tracking mitochondrial changes is the key to understand the processes of diseases related to mitochondria, which is meaningful to physiology, pathology, and pharmacology. So, a great deal of mitochondrial probes was designed and synthesized according to the principle that probes with a positive charge can target mitochondria through mitochondrial membrane potential (MMP). However, these traditional mitochondrial probes are not able to visualize and track mitochondrial changes, because their targeting abilities depend on high MMP. Once MMP decreases, they will leak from mitochondria. Herein, we designed and synthesized a red-emitting molecule rotor (SQ , sensitive to viscosity) that could visualize mitochondria with high-fidelity. The rotor was able to firmly immobilize in mitochondrial inner membrane through the cooperation of MMP and the high viscosity property of mitochondrial membrane, and it could still stain mitochondria with long-term regardless of MMP changes. Hence, the probe is able to real-time image and distinguish four kinds of mitochondria with high-fidelity in muscle tissues. In addition, SQ can monitor mitochondrial autophagy in real time. These results demonstrate that SQ is a powerful tool for high-fidelity visualizing and long-term tracking mitochondria in vitro and in vivo. [ABSTRACT FROM AUTHOR]

BP was prepared from BP bulk in the ionic liquid (IL) through ultrasonic-assisted liquid-phase exfoliation and further BP-IL-SWCNH was applied in electrochemical biosensor to detect 5-HT, which combined with machine learning (ML) based on artificial neural network (ANN) algorithm to realize intelligent analysis of 5-HT coupled with derivative voltammetry. [Display omitted] • A green synthesis of BP in IL by ultrasonic-assisted liquid-phase exfoliation was proposed. • BP-IL displayed satisfactory stability in ambient condition containing oxygen and water. • The introduction of SWCNH enhanced electrocatalytic capacity and endowed oxidase-like characteristics, • ML was established to implement intelligent analysis of 5-HT coupled with derivative voltammetry. Ultrasonic-assisted liquid-phase exfoliation is one of high-efficiency strategies for preparing two-dimensional (2D) materials. Herein, we report a facile and green synthesis of the phosphorene (BP) obtained from bulk black phosphorus crystal in the ionic liquid (IL) 1-ethyl-3-methylimidazoliumtetrafluoroborate ([EMIm]BF 4) through ultrasonic-assisted liquid-phase exfoliation under the continuous nitrogen atmosphere. To gain more insight, the morphology and composition of the as-prepared BP were characterized. The prepared BP showed satisfactory stability in ambient condition containing oxygen and water. In the following, single walled carbon nanohorn (SWCNH) was selected to enhance electrocatalytic capacity and endow oxidase-like (nanozyme) characteristics, which was further applied for electrochemical sensing of 5-hydroxytryptamine (5-HT). Derivative techniques were employed for treating voltammograms to obtain sharper and narrower voltammetric peak, transform asymmetric peak into much more symmetrical peak, reduce background interference, eliminate personal error and directly read the accurate value. Machine learning (ML) model based on artificial neural network (ANN) algorithm as an artificial intelligence approach is adopted to establish smart sensing system via the relationship between concentrations and currents in comparison with traditional linear regression model. The BP-IL-SWCNH nanozyme sensor displayed excellent electrocatalytic ability for second-order derivative voltammetric smart analysis of 5-HT range from 0.3 to 115 µM under optimal conditions. [ABSTRACT FROM AUTHOR]

The green preparation of the a-MoS x -BM nanocomposite for smart sensing baicalin. [Display omitted] • The a-MoS x -BM nanocomposite as sensing platform was prepared by a green hydrothermal method; • LSSVM displayed more superiority in practical application for smart sensing compared with ANN. Green and sustainable development provides a new idea for solving environmental pollution issues of rural biomass wastes. Amorphous molybdenum sulfide (a-MoS x) nanocomposite based on biochar microsphere (BM) as voltametric sensing platform for smart analysis of baicalin in real sample was facilely prepared. Pomelo peel was employed as the carbon source for improving electronic conductivity and environmental stability and electrocatalytic capacity of a-MoS x. A mixture consisted of the precursor of both a-MoS x and BM were treated by a co-hydrothermal method. The a-MoS x nanocomposite with porous BM was formed by centrifuging, washing, drying, pulverizing, and calcining. The structure and properties of the as-obtained nanocomposite were characterized, and the electrochemical behaviors of baicalin, parametric conditions and performance of the as-prepared sensor were investigated. Peak currents recorded by differential pulse voltammetry is proportional to baicalin concentrations in wide linear ranges from 10 nM to 5 μM with a low limit of detection of 2 nM. Machine learning algorithms like least squares support vector machine and artificial neural network was built to realize smart analysis and digital output for baicalin. Good cyclic stability, excellent voltammetric response, and satisfactory practicability will provide a promising electrochemical sensing platform for facile preparation of two-dimension nanomaterials functionalized with biochar derived from agroforestry biomass. [ABSTRACT FROM AUTHOR]

Abstract: We developed a novel nonenzymatic biosensor based on palladium/poly(3,4-ethylenedioxythiophene) (Pd/PEDOT) nanocomposite modified glassy carbon electrode (GCE) for the detection of hydrogen peroxide (H2O2). Pd/PEDOT has been successfully fabricated by a facile one-pot ‘green’ method using H2PdCl4 as an oxidant and a source of metal nanoparticles without any surfactants and templates. The as-synthesized PEDOT nanospheres are quite uniform in size (∼60nm) without aggregation and provide a good platform for anchoring the Pd nanoparticles (NPs). Pd NPs (∼4.5nm) are homogenously dispersed on surface of PEDOT nanospheres. The Pd/PEDOT nanospheres on GCE exhibit a good electrocatalytic activity towards the H2O2 reduction. The electrochemical response of Pd/PEDOT to H2O2 exhibits a low detection limit of 2.84μM in the range of 2.5×10−3–1.0mM with a high sensitivity, good repeatability, acceptable reproducibility and good long-term stability. The good recoveries achieved in spiked human urine samples demonstrated the potential application of Pd/PEDOT for H2O2 detection. [Copyright &y& Elsevier]

The support materials play a critical role for the electrocatalytic oxidation of ethanol on precious metal catalysts in fuel cells. Here, we report the poly(3,4-ethylenedioxythiophene) combined with reduced graphene oxide (PEDOT-RGO) as the support of Pd nanoparticles (NPs) for ethanol electrooxidation in alkaline medium. The as-prepared Pd/PEDOT-RGO composite catalysts are characterized by Raman spectrometer, X-ray diffraction, transmission electron microcopy, and scanning electron microcopy. PEDOT-RGO composite with the porous structure facilitates the dispersion of Pd NPs with a smaller size leading to the increase of electrochemical active surface area. The electrochemical properties and electrocatalytic activities of Pd/PEDOT-RGO hybrid are evaluated by cyclic voltammetry, chronoamperometry, CO stripping voltammetry, electrochemical impedance spectroscopy (EIS) and Tafel analysis. The results suggest that Pd/PEDOT-RGO hybrid shows a higher electrocatalytic activity, a better long-term stability, and the poisoning tolerance for the ethanol electrooxidation than Pd on carbon black. EIS and Tafel analysis indicate that PEDOT-RGO improves the kinetics of ethanol electrooxidation on the Pd NPs and is an efficient support in fuel cells. [ABSTRACT FROM AUTHOR]

Abstract: A ternary composite catalyst of Pt–WO3–TiO2 has been successfully prepared by a chemical method. The prepared composite was systematically characterized by UV–vis diffuse reflectance absorption spectra (DRS), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and transmission electron microscopy (TEM). The electrocatalytic properties of Pt–WO3–TiO2 for methanol oxidation in an alkaline medium were evaluated by the cyclic voltammetry (CV) and chronoamperometry (CA) with or without visible light irradiation. Compared with the pure TiO2, the introduction of WO3 extends its absorption edge to visible light region. Under visible light illumination, the Pt–WO3–TiO2 composite catalyst exhibits higher electrocatalytic activity toward methanol oxidation in comparison with its counterpart, the pure Pt–TiO2 catalyst. [Copyright &y& Elsevier]

Abstract: A facile and efficient green protocol for the synthesis of carbazole derivatives containing a six-membered ring, via an aldol condensation and solvent-free Michael addition reaction, has been developed. The compounds were characterized by 1H NMR, 13C NMR, IR, ESI-MS and HR-MS spectroscopic techniques and also, for one example, by X-ray crystallography. The cyclohexyl unit was introduced into the carbazole derivatives and utilized as a sterically demanding group for the purpose of increasing the non-planarity of the carbazole derivatives and reducing self-quenching, leading to improved optical and electronic properties. The influence of solvent polarity on the ultraviolet absorption and fluorescence characteristics was observed and investigated. The majority of the carbazole derivatives have high fluorescence quantum yields in dichloromethane, ethanol, acetonitrile and DMF. [Copyright &y& Elsevier]

Two soluble conjugated polythiophenes, poly[3-(N-butyl-4-piperidinemethylene)-thiophene] (P3BLMT), and poly[3-(N-butyryl-4-piperidinemethylene)-thiophene] (P3BRMT) have been synthesized successfully in chloroform using FeCl3as an oxidizing agent. In P3BLMT and P3BRMT, substituted piperidine rings are connected with the polythiophene backbone through carbon–carbon double bond. While in the two polythiophenes, the significant difference is the substituent linked to the N-atom of the piperidine effectively. Structures of the monomers and the corresponding soluble polymers were elucidated by1H NMR,13C NMR, and IR. Average molecular weights have been determined by gel permeation chromatography. Photoluminescence spectra and ultraviolet–visible spectra of the two polythiophenes in both solution and solid states were also investigated, and all peaks were bathochromically shifted when they were measured in the solid state. The results of optical and electrochemical measurements indicate that the carbonyl group on the side-chain has obvious influence on the electrochemical properties of the conjugated polythiophenes. In addition, the polymers were also characterized by cyclic voltammetry and scanning electron microscopy. [ABSTRACT FROM AUTHOR]

5-Aminoindole and 3,4-ethylenedioxythiophene (EDOT) were copolymerized electrochemically on a carbon cloth (CC) electrode in an aqueous sulfuric acid solution. The as-prepared copolymer was characterized by cyclic voltammogram, SEM, and UV-vis and FT-IR spectra through which the electrochemical properties, structure, and composition of the as-obtained copolymer were determined. The electrochemical activity and stability of the as-formed copolymer are significantly improved in comparison with poly(5-aminoindole) due to the incorporation of EDOT units into the conjugated chain. The copolymer film-modified CC electrode was used as substrate for Pt particle deposition (denoted as Pt/copolymer/CC), and then, its catalytic activity towards formic acid electrooxidation was studied. Experimental results indicate that the catalytic activity of Pt/copolymer/CC towards formic acid electrooxidation is enhanced in comparison with that of Pt/homopolymer/CC, which can be attributed to the homogeneous distribution of Pt nanoparticles on the copolymer/CC substrate and the improved electrochemical activity of the copolymer film. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we describe the electropolymerization of 9-fluorenemethanol (FMO) in boron trifluoride diethyl etherate, which leads to low-potential electrodeposition of semiconducting poly(9-fluorenemethanol) (PFMO) film under optimized conditions. The as-formed PFMO film shows favorable solubility in common organic solvents, good redox activity and stability with a conductivity of 10−2 Scm−1, good thermal stability, and uniform morphology. Besides, PFMO exhibits electrochromic nature with its color changing from pale brown in its reduced form to dark blue upon oxidation, but its electrochromic performances are relatively poor. Fluorescence spectral studies demonstrated that soluble PFMO is highly fluorescent with its maximum emission at 418nm and a quantum yield of 0.52, and it can emit bright blue light under 365nm UV light irradiation. [Copyright &y& Elsevier]

Abstract: Pt-based catalysts with free-standing poly[poly(N-vinyl carbazole)] (PPVK) as support (Pt–M/PPVK, M=Pd, Au, and Ru) on a glassy carbon electrode (GCE) have been successfully prepared by an electrochemical method. Cyclic voltammetric and chronoamperometric methods are used to investigate the electrocatalytic activity and stability of as-prepared catalysts. It is found that PPVK film as support effectively enhances the catalytic acitivity of Pt nanoparticles for methanol electro-oxidation in alkaline medium. The bimetallic Pt–M nanoparticles obtained potentiostatically on the PPVK film show the higher electrocatalytic activity than bare Pt/GCE and JM Pt/C. In addition, to pin down the external influencing factors, systematic studies have been conducted on the methanol electro-oxidation at as-prepared catalysts as a function of platinum loading, PPVK mass, methanol and KOH concentrations. [Copyright &y& Elsevier]

Abstract: Layered electrochemically reduced graphene oxide (ER-GO) sheets incorporated with poly(3,4-ethylenedioxythiophene) (PEDOT) have been fabricated as an efficient support for Pt nanoparticles on a glassy carbon (GC) electrode. The as-prepared Pt-loaded PEDOT/ER-GO composite electrode exhibits not only the high mass peak current density (390 A g−1) but also the good long-term catalytic stability toward the ethanol electrooxidation. The Pt/PEDOT/ER-GO also shows stronger tolerance to poisoning species compared with the commercial JM 20% Pt/C electrode. The high electrocatalytic activity of Pt/PEDOT/ER-GO is mainly described to the good electrochemical activity of PEDOT/ER-GO composites and the well-dispersed Pt nanoparticles resulting in the large electrochemical active surface area of Pt (47.1 m2 g−1). [Copyright &y& Elsevier]

Abstract: Water-soluble poly(9-aminofluorene) (P9AF) was facilely synthesized by the direct electropolymerization of commercially available monomer 9-aminofluorene in boron trifluoride diethyl etherate, and its preliminary application as a fluorescent chemosensor for the highly selective and sensitive detection of Fe(III) and inorganic phosphates (Pi) in an organic buffer 2-[4-(2-hydroxyethyl)-1-piperazinyl]ethanesulfonic acid (HEPES) (pH 7.0) was investigated. The one-step electrosynthesized P9AF with high quality and water-solubility possessed good fluorescence properties. P9AF was employed to sense Fe(III) in aqueous solution, displaying high selectivity, pronounced sensitivity, low detection limit, and fast response. On binding to Fe(III), exceptional fluorescence quenching of P9AF occurred, demonstrated by a >94% reduction in the fluorescence intensity. P9AF–Fe(III) complex exhibited high sensitivity and rapid response to Pi with turn-on fluorescence. The working mechanism was proposed and confirmed by transmission electron microscopy. The determination of Fe(III) in real samples and the interaction of P9AF with Fe(III) and Pi in living cells were investigated with satisfying results, showing that the cost-effective, water-soluble, and electrosynthesized P9AF has potential application in biological system and environment. [Copyright &y& Elsevier]

Abstract: A simple, sensitive, and reliable method for the voltammetric determination of roxithromycin (RM) at the surface of the fabricated poly(3,4-ethylenedioxythiophene) (PEDOT) modified Au electrode has been successfully developed. The electrochemical behavior of RM at the surface of the modified electrode was investigated by cyclic voltammetry and differential pulse voltammetry. The influence of experimental parameters including PEDOT modified various solid electrodes, supporting electrolytes, nano-modified materials, buffer solutions, pH values and scan rates on the response of RM were studied. Under optimal conditions, the as-prepared modified electrode can be employed to the quantification of RM with a linear range covering from 0.08 to 20μM, a high sensitivity of 0.9921μAμM−1, and a low detection limit of 0.0267μM. Furthermore, the proposed modified electrode displayed high stability, good reproducibility and high sensitivity. The voltammetric determination of RM content in its capsule samples by using the as-prepared modified electrode also showed a satisfactory result with the good recovery in the range from 98.9% to 102.0%. The good result on the voltammetric determination of RM also indicated that the as-fabricated PEDOT modified Au electrode will be a good candidate for the electrochemical determination and analysis of other macrolide antibiotics. [Copyright &y& Elsevier]

Systematic research on the synthesis, chemical oxidative polymerization of 3,4-ethylenedithiathiophene (EDTT) in the presence of surfactants or not, and solid-state polymerization of 2,5-dibromo-3,4-ethylenedithiathiophene (DBEDTT) and 2,5-diiodo-3,4-ethylenedithiathiophene (DIEDTT) under solventless and oxidant-free conditions has been investigated. Effects of oxidants (Fe3+ salts, persulfate salts, peroxides, and Ce4+ salts), solvents (H2O, CH3CN/H2O, and CH3CN), surfactants, and so forth on polymerization reactions and properties of poly(3,4-ethylenedithiathiophene) (PEDTT) were discussed. Characterizations indicated that FeCl3 was more suitable oxidant for oxidative polymerization of EDTT, while CH3CN was a better solvent to form PEDTT powders with higher yields and electrical conductivities. Dispersing these powders in aqueous polystyrene sulfonic acid (PSSH) solution showed better stability and film-forming property than sodium dodecylsulfate and sodium dodecyl benzene sulfonate. Oxidative polymerization of EDTT in aqueous PSSH solutions formed the solution processable PEDTT dispersions with good storing stability and film-forming performance. Solvent treatment showed indistinctive effect on electrical conductivity of free-standing PEDTT films. As-formed PEDTT synthesized from solid-state polymerization showed similar electrical conductivity, poorer stability, but better thermoelectric property than oxidative polymerization. Contrastingly, PEDTT synthesized from DIEDTT showed higher electrical conductivity (0.18 S cm−1) than DBEDTT which showed better thermoelectric property with higher power factor value (6.7 × 10−9 W m−1 K−2). © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 [ABSTRACT FROM AUTHOR]

A novel semiconducting oligo(9-fluorenylideneacetic acid) (OFYA) with good redox activity and stability was successfully electrosynthesized by direct anodic oxidation of 9-fluorenylideneacetic acid (FYA) in CH2Cl2 containing boron trifluoride diethyl etherate (BFEE) as the supporting electrolyte. The as-formed OFYA film was readily soluble in dimethyl sulfoxide and tetrahydrofuran, and partly soluble in water, alcohol, acetonitrile and acetone. FT-IR and 1H NMR spectra, together with computational results proved that FYA was probably polymerized through the coupling at C(2) and C(7) positions. Further, OFYA was a typical green light-emitter with maximal emission at 555 nm and its fluorescence quantum yield was distinctly improved in comparison with that of the monomer. The oligomer was also studied by UV-vis spectroscopy, MALDL-TOF mass spectrometry, and thermal analysis, respectively. [ABSTRACT FROM AUTHOR]

Bromo-group-substituted oligopyrene films were electrochemically synthesized by direct anodic oxidation of 1-bromopyrene (BrP) in boron trifluoride diethyl etherate (BFEE). The oxidation potential of BrP was measured to be approximately 0.52 V (vs. Ag/AgCl), which was much lower than that detected in a neutral electrolyte such as acetonitrile (1.2 V vs. Ag/AgCl) and CHCl (1.25 V vs. Ag/AgCl). Oligo(1-bromopyrene) (OBrP) films showed good redox activity in both BFEE and concentrated sulfuric acid. Fourier transform infrared spectroscopy, H NMR, and theoretical calculations showed that the electropolymerization of the BrP monomer mainly occurred at the C, C, and C positions. As-formed OBrP was a typical blue light emitter with fluorescent quantum yields of 0.27, also emitted strong and bright blue photoluminescence at excitation of 365 nm UV light. Furthermore, the films were readily soluble in dimethyl sulfoxide, CHCl, acetonitrile, and acetone. All these results indicate that the striking OBrP films have many potential applications in various fields, such as optoelectronic materials, DNA fluorescence probes, and electrochemical sensors. [ABSTRACT FROM AUTHOR]

Poly(1,12-bis(carbazolyl)dodecane- co-thieno[3,2- b]thiophene) (P(2Cz-D- co-TT)), a conducting copolymer was synthesized electrochemically by direct anodic oxidation of 1,12-bis(carbazolyl)dodecane (2Cz-D) and thieno[3,2- b]thiophene (TT) in boron trifluoride diethyl ethrate containing 30% (vol) dichloromethane. As-formed copolymers exhibited high redox activity and reversibility and good conductive properties. The emitting property of as-formed copolymer was different from those of respective homopolymers, and could be tuned by changing the initiate monomer feed ratios. Thermoelectric investigations revealed that the electrical conductivities of as-obtained copolymer films were between 0.1 and 0.3 S cm at ambient temperature, lower than that of polythieno[3,2- b]thiophene (PTT) (0.42 S cm) but two orders of magnitude higher than that of poly(1,12-bis(carbazolyl)dodecane) (P2Cz-D) (10 S cm). The Seebeck coefficients and the power factors of the copolymers were improved with different degrees compared with those of PTT and P2Cz-D. As expected, the thermoelectric performance of PTT and P2Cz-D were both improved through copolymerization, which may be beneficial to the exploration and investigation of novel organic thermoelectric materials. [ABSTRACT FROM AUTHOR]

Green-light-emitting poly(diphenylmethylenefluorene) (PDPMF) was synthesized electrochemically by direct anodic oxidation of diphenylmethylenefluorene (DPMF) in dichloromethane (CHCl) and boron trifluoride diethyl etherate (BFEE) binary solution. The oxidation potential of DPMF in this medium was measured to be only 0.78 V versus Ag/AgCl, which was lower than that determined in CHCl (1.0 V versus Ag/AgCl) or acetonitrile (ACN) (1.16 V versus Ag/AgCl) with 0.1 mol L tetrabutylammonium tetrafluoroborate (BuNBF) as the supporting electrolyte. The as-formed PDPMF films showed good electrochemical behavior and high thermal stability. Fluorescent spectra indicate that PDPMF is a good green-light-emitter with strong and bright green or yellow-green photoluminescence under 365 nm UV light. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a stable sandwich-type amperometric biosensor based on poly(3,4-ethylenedioxythiophene) (PEDOT)–single walled carbon nanotubes (SWCNT)/ascorbate oxidase (AO)/Nafion films for detection of l-ascorbic acid (AA) was successfully developed. PEDOT–SWCNT nanocomposite and Nafion films were used as inner and outer films, respectively. AO was immobilized between these two films. The PEDOT–SWCNT nanocomposite films were characterized by electrochemical impedance spectroscopy and scanning electron microscopy. The influence of detection potential and temperature on the biosensor performance was examined in detail. Despite the multilayer configuration, the biosensor exhibited a relatively fast response (less than 10s) and a linear range from 1μM to 18mM (a correlation coefficient of 0.9974). The sensitivity of the biosensor was found to be 28.5mAM−1 cm−2. Its experimental detection limit was 0.7μM (S/N =3) and the apparent Michaelis–Menten constant (K m) was calculated to be 18.35mM. Moreover, the biosensor exhibited good anti-interferent ability and excellent long-term stability. All the results showed that such sandwich-type PEDOT–SWCNT/AO/Nafion films could provide a promising platform for the biosensor designs for AA detection. [Copyright &y& Elsevier]

Abstract: In fuel cells, Pt is often employed as an electrode material to facilitate electrochemical reaction processes, in which morphology plays an important role. In this work, three kinds of Pt flowers have been prepared on a glassy electrode substrate via a facile electrochemical deposition in a solution of H3PO4; by controlling work potentials at −0.1 V, −0.2 V and −0.3 V, cauliflower-like, needle-like and rose-like shapes of Pt micro/nanoparticles as confirmed by SEM and XRD are obtained, respectively. Taking methanol oxidation as a model reaction and using CO stripping voltammogram in an acid medium, the electrocatalytic performance of as-prepared three Pt flowers has been evaluated. The three Pt flowers show different electrocatalytic activities, and the needle-like Pt flowers present the highest catalytic activity for electrooxidation of methanol and CO. [Copyright &y& Elsevier]

Abstract: A Pt-based composite electrode material has been developed by dispersing Pt nanoparticles on a porous poly(o-methoxyaniline) (POMA) film, which was produced via electropolymerization on a glassy carbon (GC) electrode. As-formed Pt/POMA/GC electrode was characterized by SEM, EDX and electrochemical analysis. Furthermore, the composite electrode material was evaluated by its electrocatalytic performance for formic acid oxidation using cyclic voltammetry and chronoamperometry methods. Compared to Pt deposited on bare GC (Pt/GC), Pt/POMA/GC exhibits higher catalytic activity and stronger poisoning-tolerance ability towards formic acid electro-oxidation. The improved performance is attributed to the synergetic effect between Pt and POMA. Also, as demonstrated by CO stripping voltammograms, the interference of CO on Pt/POMA/GC is greatly weakened. These results suggest that the POMA film has great potential to serve as a promising support material for the electrocatalytic oxidation of formic acid. [Copyright &y& Elsevier]

Two novel triazine-based dendrimers comprising a dithienylethene core and eight and 16 ethyl groups around the periphery were synthesised in high yields in a convergent way, without using tedious protection and chromatographic separation steps. Their optical properties such as photochromism, fluorescence emission and film-forming behaviour were investigated. The new symmetrical dendritic dithienylethenes showed typical photochromic behaviour in solution and good film-forming performance in a poly(methyl methacrylate) (PMMA) matrix. Moreover, the dendrimers have demonstrated remarkable fluorescence enhancement and good solubility in common organic solvents, compared with the corresponding small molecule diarylethene. Thus, the new dendrimers as optoelectronic materials, have potential applications in optical storage, photo-switches, and so on. [ABSTRACT FROM AUTHOR]

Abstract: Surfactants with a polycyclic aromatic moiety and a long hydrocarbon chain, carbazole-tailed amphiphilic imidazolium ionic liquids 1-[n-(N-carbazole)alkyl]-3-methylimidazolium bromide [CzC n MIm]Br (n =10 and 12), were designed to disperse carbon nanotubes (CNTs) in aqueous solutions. UV–vis–NIR spectra were performed to determine the dispersion of CNTs and the optimal concentration (C opt) of [CzC n MIm]Br. Compared with [C n MIm]Br, [CzC n MIm]Br was more effective with the smaller C opt and more individual CNTs, reflecting the effect of the carbazole moiety. The adsorption of [CzC n MIm]Br molecules on CNTs was investigated by zeta-potential, surface tension, fluorescence, and 1H NMR. Having zeta-potentials higher than 15mV contributed to the long-term stability of aqueous CNT dispersions. The significant fluorescence quenching and the upfield shift of carbazole protons support the π–π stacking interaction between carbazole moieties and the π-networks of CNTs. Meanwhile, the upfield shift of imidazolium protons indicates the cation–π interaction between the imidazolium ions and the π-networks of CNTs. [Copyright &y& Elsevier]

Abstract: Polynaphthalene films with electrical conductivity of 10−3 Scm−1 were successfully electrosynthesized by direct anodic oxidation of 1,1′-binaphthyl (BN) and 1,1′-bi-2-naphthol (BNO) in CH2Cl2 containing additional boron trifluoride diethyl etherate (BFEE). The introduction of BFEE greatly lowered the onset oxidation potentials of the monomers compared with other supporting electrolytes. The resulting poly(1,1′-binaphthyl) (PBN) films exhibited good redox activity and stability in different monomer-free electrolytes. Moreover, FT-IR spectra and quantum chemistry calculation results proved that PBN and poly(1,1′-bi-2-naphthol) (PBNO) were both synthesized mainly through the coupling of the monomers at α-positions of the naphthalene ring. Fluorescence spectral determination showed that the polymers were typical blue light-emitters with solution quantum yields of 0.17 and 0.13, respectively. The substitution of hydroxyl and naphthyl groups did not change the emission wavelength of polynaphthalene (about 417nm). Surface morphology determination revealed that regular particles with different sizes were orderly assembled on ITO electrode after electrochemical growth. [ABSTRACT FROM AUTHOR]

Abstract: Pt is one of the most important electrode materials employed in direct methanol fuel cell, and many efforts have been directed to improving its electrocatalytic performance. In this work, Pt–TiO2 nanocomposites are successfully prepared by a sol–gel method. As revealed by TEM, Pt nanoparticles with an average size of 2.6 nm are well uniformly dispersed on porous TiO2. XRD structural characterization indicates that Pt possesses a face centered cubic crystal structure while TiO2 is in the format of both rutile and anatase phases. The electrochemical performance of as-prepared nanocomposite electrode (Pt–TiO2/ITO) is evaluated by studying the electrocatalytic oxidation of methanol in an alkaline medium with or without UV illumination. Comparative experiments evince that the electrochemical performance of Pt–TiO2/ITO for methanol electrooxidation is markedly improved under UV illumination. Under UV illumination, moreover, the poisoning resistance of Pt–TiO2/ITO for methanol electrooxidation is significantly improved, as supported by the results of time-coursed current measurements. [ABSTRACT FROM AUTHOR]

Abstract: Highly conducting free-standing poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT/PSS) films with room-temperature electrical conductivity of about 300Scm−1 were successfully prepared from PEDOT/PSS solution containing additives (DMSO or EG) on the smooth and flexible polypropylene (PP) film substrate with contact angle of 87°. As formed free-standing PEDOT/PSS films possess good flexibility and can be easily cut into various shapes with a knife. The contact angle of substrate has significant effect on the preparation of free-standing PEDOT/PSS films. Additionally, the process of adding DMSO or EG did not result in the change of carrier concentration but the increase of carrier mobility. The free-standing PEDOT/PSS film showed high electrical conductivity and stable Seebeck coefficient and its figure of merit (ZT) with high environment stability can be up to 10−2, one order of magnitude higher than that of pressed PEDOT/PSS pellets (10−3). [Copyright &y& Elsevier]

Abstract: Recyclability of noble metal catalysts is a challenging issue when dealing with their industrial applications. Smart pH-sensitive Pt nanoparticles were successfully prepared for the first time by using octa(N,N-diacetic acid phenylamine)silsesquioxane (OAPAS) as a macromolecular protective agent. As-prepared Pt nanoparticles can self-aggregate or redisperse by only changing the pH of the system solution. In the weak acidic or alkaline solution (pH>4.0), the Pt nanoparticles dispersed homogenously; while in the acidic solution (pH=2.5), they self-aggregated. The dynamic self-aggregation and redispersion processes of the Pt nanoparticles driven by pH changes were revealed by transmission electron microscopy measurements. Electrocatalytic experiments proved that the platinum nanoparticles as a recyclable catalyst showed excellent activity for the hydrogenation of aldehyde after runs of five times. Such platinum nanoparticles are thereby anticipated to have great potential functioning as “smart” catalysts for industrial applications. [Copyright &y& Elsevier]

Abstract: Novel composite catalysts have been fabricated by the electrodeposition of Pt onto the glassy carbon electrode (GC) modified respectively with polyindole (PIn) and poly(5-methoxyindole) (PMI) and used for the electrooxidation of methanol in acid solution of 0.5M H2SO4 containing 1.0M methanol. As-formed composite catalysts are characterized by SEM, XRD and the electrochemical methods. The results of the catalytic activity for methanol oxidation show that the two composite catalysts exhibit higher catalytic activity and stronger poisoning-tolerance than Pt/polypyrrole/GC (Pt/PPy/GC) and Pt/GC. Electrochemical impedance spectroscopy indicates that the methanol electrooxidation on the composite catalysts at various potentials shows different impedance behaviors. At the same time, the charge-transfer resistance for electrooxidation of methanol on Pt/PIn/GC and Pt/PMI/GC is smaller than those on Pt/PPy/GC and Pt/GC. The present study shows a promising choice of Pt/PIn and Pt/PMI as composite catalysts for methanol electrooxidation. [Copyright &y& Elsevier]

Abstract: Four novel composite catalysts have been developed by the electrodeposition of Pt onto glassy carbon electrode (GCE) modified with polyindoles: polyindole, poly(5-methoxyindole), poly(5-nitroindole) and poly(5-cyanoindole). As-formed composite catalysts are characterized by SEM, XRD and electrochemical analysis. Compared with Pt nanoparticles, respectively, deposited on the bare GCE and on the GCE modified with polypyrrole, the four newly developed composite catalysts exhibit higher catalytic activity towards formic acid electrooxidation by improving selectivity of the reaction via dehydrogenation pathway and thus mostly suppressing the generation of poisonous COads species. The enhanced performance is proposed to come from the synergetic effect between Pt and polyindoles and the increase of electrochemical active surface area (EASA) of Pt on polyindoles. [Copyright &y& Elsevier]

Abstract: Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) films have been electrochemically polymerized in situ on ITO glass substrate in boron trifluoride diethyl etherate electrolyte (BFEE). Cyclic voltammograms show good redox activity and stability of the PEDOT films. These films had been directly used to fabricate organic–inorganic hybrid solar cells with the structure of ITO/PEDOT/ZnO:MDMO-PPV/Al. The solar cells made of electrochemically polymerized films exhibit higher energy conversion efficiencies compared with that prepared by the spin-coating method, and the highest value is 0.33%. This in-situ electropolymerized method effectively simplifies fabricating procedures and may blaze a facile and economical route for producing high-efficiency solar cells. [Copyright &y& Elsevier]

Abstract: A novel composite catalyst, Pt nanoparticles supported on poly(5-nitroindole) (Pt/PNI), has been successfully prepared by the electrochemical method and used for the electrooxidation of methanol in alkaline media. As-prepared Pt/PNI was characterized by SEM, EDX and electrochemical methods. The results of the catalytic activity for methanol oxidation showed that Pt/PNI had higher catalytic activity and stronger poisoning-tolerance than Pt/Pt, Pt/GC and the common Pt electrode. The effects of different parameters related to the methanol oxidation reaction kinetics, such as Pt loading, mass of PNI film, concentration of methanol and KOH, potential scan rate, have also been investigated. The present study showed a promising choice of Pt/PNI as composite catalyst for methanol electrooxidation in alkaline medium. [Copyright &y& Elsevier]

Abstract: An air and moisture stable ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate (bmimPF6) was utilized as an electrolyte for the direct anodic oxidation electropolymerization of fluorene. The corresponding electroactive polyfluorene films showed good redox activity and structural stability. 1H NMR and FTIR spectra together with density functional theory calculations indicated that the polymerization of fluorene occurred at the C2 and C7 positions. Scanning electron microscopy results demonstrated that smooth and compact polyfluorene films were obtained, due to the use of bmimPF6 as both the growth medium and the electrolyte. Doped polyfluorene films were examined to oxidize formic acid in 0.5mol/L sulfuric acid by cyclic voltammetry and demonstrated stable electrocatalytic activity, showing their potential use in fuel oxidation. [Copyright &y& Elsevier]

• Ionic crosslinking can improve the ordering and interplanar spacing of polyaniline. • Further enlarge the interplanar spacing of polyaniline via a simple heat treatment. • The as-prepared polyaniline has nearly quadrupled the specific capacitance. • This new form polyaniline exhibits excellent rate performance. Polyaniline (PANI) with high theoretical specific capacitance demonstrates a broad application prospect in supercapacitors, but the fact that the disorder and entanglement based on abundant one-dimensional polyaniline chains lead to low actual specific capacitance and poor rate capacity. In this work, ionic crosslinking can effectively control the randomly oriented chain growth and the degree of polyaniline aggregation through simply replacing the connector. The degree of oxidation, conjugation length and π-π stacking of polyaniline chains were increased, causing more plane accumulation on or between the molecular chains. The polyaniline structure tends to be ordered, which provides more active sites for the Faraday reaction, and after heat treatment, the ion transport channel of the prepared material is further expanded, exhibiting four times the specific capacitance of in situ polymerized polyaniline as well as excellent rate performance. The symmetrical supercapacitor displays a considerable energy density and fine integration capability. Such results suggest that ionic crosslinking provides the possibility to prepare high-performance supercapacitor electrode materials. A new form of polyaniline based on ionic crosslinking can efficiently improve the ordering and interplanar spacing, which facilitated the contact between electrode material and electrolyte, and thereby exhibiting excellent specific capacitance and rate performance. [Display omitted] [ABSTRACT FROM AUTHOR]

Hexavalent chromium (Cr(VI)) pollution is related to human health, and the detection of its concentration has a decisive effect on pollution treatment. In this work, we designed a Cr 2 O 7 2− sensor P(Fmoc-Osu) and applied it in farmland. In the boron trifluoride diethyl etherate solution, the monomer Fmoc-Osu was electropolymerized and obtained its conjugated polymer P(Fmoc-Osu). The introduction of succinimide and carbonic ester group in side chain enabled it to show high selectivity to Cr 2 O 7 2− in comparison to anions and twenty amino acids. Furthermore, by taking advantage of the signal amplification effect of a conjugated polymer, P(Fmoc-Osu) could analyze Cr 2 O 7 2− in trace amounts and the limit of detection was 8.3 fM. For agricultural application, we employed it in farmland water, soil, Chinese cabbage, carrot and the results showed a satisfactory result. All these results showed that P(Fmoc-Osu) is an efficient tool to detect Cr 2 O 7 2− in practical application. An ultra-sensitive fluorescent sensor P(Fmoc-Osu) could directly detect Cr 2 O 7 2− in farmland. [Display omitted] • Conjugated polymer P(Fmoc-Osu) with blue fluorescence was easily obtained through electropolymerization. • P(Fmoc-Osu) had a high anti-interference ability when sensing Cr 2 O 7 2−, avoiding the interference of common anions and amino acids. • P(Fmoc-Osu) was highly sensitive to Cr 2 O 7 2−, and the limit of detection was 8 fM. • P(Fmoc-Osu) had a high anti-interference ability to Cr 2 O 7 2−, avoiding the interference of common anions and amino acids. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nanozyme sensor comprised of electro-synthesized imprinted PEDOT with graphene-like MoS 2 was prepared. • Imprinted nanozyme was employed for detection of luteolin with good electrochemical sensing performance. • The proposed method electrochemically detected luteolin in Gnaphalium affine obtained acceptable recoveries. A novel nanozyme sensor based on the electro-synthesized molecularly imprinted conducting poly(3,4-ethylenedioxythiophene) (PEDOT) nanocomposite with graphene-like two-dimensional layered molybdenum disulfide (MoS 2) was successfully prepared for electrochemical detection and analysis of luteolin in Gnaphalium affine. MoS 2 -MIPs were prepared facilely by electrochemical polymerization of monomer 3,4-ethylenedioxythiophene in the presence of both modifier MoS 2 and template molecule luteolin that can change the morphological structure and specific surface area of PEDOT, enhance electronic conductivity of MoS 2 , and improve the recognition capability and electrocatalytic capacity of electrode interface. The morphological structure of MoS 2 -MIPs was characterized by SEM, and its electrochemical performance and sensing parameters were investigated by voltammetry. The electrochemical response of luteolin was recorded by MoS 2 -MIPs in the linear concentration range from 3 × 10-7 to 3 × 10-5 Μ with limit of detection of 0.04 μΜ under the optimal conditions, which was successfully employed for electrochemically detecting luteolin in Gnaphalium affine with acceptable recoveries in comparison with high-performance liquid chromatography. This will provide a new nanozyme sensing platform comprised of electro-synthesized molecularly imprinted conducting polymers and graphene-like two-dimensional layered nanomaterials. [ABSTRACT FROM AUTHOR]

Improved supercapacitor capacitance performance of PEDOT:PSS-based electrodes is obtained from various structural regulation of multi-dimensional carbon materials. [Display omitted] • Optimize conductive polymer-based electrodes by compositing multi-dimensional carbons. • The capacitance of PEDOT:PSS/rGO film increase to 215.6 F g−1 at 1 A g−1. • Provide a comparatively meaningful reference for the capacitive energy storage field. The rapid development of flexible smart electronics upgrades the renewal of energy storage equipment, especially supercapacitors. Conductive polymers (CPs) with easily regulative structures are expected to apply in supercapacitors as excellent electrode materials. In this work, composite materials systems based on a single high-conductivity CP, poly (3, 4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS), are used to explore the effect of structural regulation on the capacitive performance by compositing with multi-dimensional carbon materials (0D C 60 , 1D SWCNT, and 2D rGO). Benefited from the structural regulation of multi-dimensional carbon materials, composite films show improved capacitance performance, especially PEDOT:PSS/rGO film reveals 1.25 times improved specific capacitance value and a good rate capability (~97.8%). This study provides a feasible reference for the design and optimization of CP-based composites for supercapacitors. [ABSTRACT FROM AUTHOR]

Photocatalysis is regarded as a promising technology for removal of nitrogen oxide (NO), however, the low photocatalytic efficiencies under visible light irradiation and the deactivation of the photocatalyst are as yet the significant issues that should be addressed. In this work, visible-light-driven Bi 2 Ti 2 O 7 /CaTiO 3 heterojunction composites were synthesized by a facile in-situ hydrothermal method. The Bi 2 Ti 2 O 7 /CaTiO 3 composites displayed superior visible light photocatalytic activity than pure CaTiO 3 and pure Bi 2 Ti 2 O 7 in the removal of NO at the 600 ppb level in air. Among all the composites, Bi 2 Ti 2 O 7 /CaTiO 3 containing 20 wt% Bi 2 Ti 2 O 7 exhibited the best photocatalytic activity, achieving a maximum removal efficiency of 59%. The improved photocatalytic performance is mainly attributed to the strong visible-light-absorbing ability, the presence of an appropriate density of oxygen vacancy defects and the formation of heterojunction between CaTiO 3 and Bi 2 Ti 2 O 7 , resulting in an efficient charge separation at the interface as proven by photoluminescence (PL) and photo-induced current measurements. According to trapping experiments and spin-trapping ESR analysis, the •O 2 − and h+ are the principal reactive species involved in the photocatalytic NO removal. In addition, the as-obtained Bi 2 Ti 2 O 7 /CaTiO 3 composite showed good chemical stability, which is beneficial for practical applications in air pollution removal. [Display omitted] • Bi2Ti2O7/CaTiO3 composites were synthesized by a facile hydrothermal method. • The Bi2Ti2O7/CaTiO3 composites showed enhanced visible-light photocatalytic activity for NO removal. • The Charge transfer mechanism in Bi2Ti2O7/CaTiO3 composite was discussed in detail. • The NO removal pathway was proposed. [ABSTRACT FROM AUTHOR]

Abstract: The direct anodic oxidation electropolymerization of 3,4-ethylenedioxythiophene (EDOT) in IL microemulsions, BmimPF6/Tween 20/H2O, has been investigated for the first time. Electrochemical measurements indicated that among water-in-BmimPF6 (W/IL), bicontinuous (B.C.), and BmimPF6-in-water (IL/W) sub-regions in BmimPF6/Tween 20/H2O system, IL/W was the most suitable for the electropolymerization of EDOT, while the electropolymerization did not happen in W/IL. The use of IL microemulsions remarkably reduces the amount of IL, especially for IL/W. UV–vis spectra confirmed the formation of PEDOT. Scanning electron microscopy results demonstrated that nanostructures of compact PEDOT films were still obtained as in pure IL, implying their possible utilization in ion-selective electrodes, ion-sieving films, and matrices for hosting catalyst particles. [Copyright &y& Elsevier]

Abstract: Poly(9-bromofluorene) (PBFe) film, a novel polyfluorene derivative, was synthesized electrochemically by direct oxidation of 9-bromofluorene (BFe) in boron trifluoride diethyl etherate (BFEE) mixed with 15% (by volume) trifluoroacetic acid (TFA) for the first time. The oxidation potential of BFe in this medium was measured to be only 1.30V vs. SCE, which was much lower than that determined in acetonitrile+0.1molL−1 Bu4NBF4 (1.70V vs. SCE). Dedoped PBFe films were partly soluble in dimethyl sulfoxide (DMSO) and ethanol. PBFe films obtained from this medium showed good electrochemical behavior even in concentrated sulfuric acid. The structure and morphology of the polymer were studied by UV–vis spectroscopy, FT-IR spectroscopy, 1H NMR spectroscopy, MALDI–TOF mass spectrometry and scanning electron microscopy, respectively. The results of quantum chemistry calculations and the spectroscopies of dedoped PBFe indicated the polymerization mainly occurred at C(2) and C(7) positions. Fluorescent spectral studies indicate that PBFe is a good blue light emitter. Thermal Analysis implied PBFe films had better thermal stability compared with polyfluorene and poly(9-fluorenone). [Copyright &y& Elsevier]

Abstract: High quality poly(indole-5-carboxylic acid) (PICA) films were synthesized electrochemically by direct anodic oxidation of indole-5-carboxylic acid (ICA) in boron trifluoride diethyl etherate (BFEE) containing additional 80% diethyl ether (EE) (by volume). PICA films obtained from this medium showed good electrochemical behavior and good thermal stability with a conductivity of 10−2 Scm−1. The doping level of PICA increased during electrochemical growth processes. Dedoped PICA films were soluble in dimethyl sulfoxide (DMSO). The structure of the polymer were studied by UV–vis spectroscopy, FT-IR spectroscopy and 1H NMR spectroscopy, which indicated that the polymerization occurred at C(2) and C(3) position. Fluorescent spectral studies indicated that PICA was a good blue-light emitter. [Copyright &y& Elsevier]

Abstract: High quality freestanding polyazulene (PAz) films were synthesized electrochemically by direct anodic oxidation of azulene (Az) in pure boron trifluoride diethyl etherate (BFEE). The oxidation potential of Az in this medium was measured to be only 0.75 V vs. SCE. PAz films obtained from BFEE showed good electrochemical behavior with conductivity of 2.2 S cm−1, which indicated that BFEE was a good medium for the electrosyntheses of PAz films. Structural studies implied that the Az units remained intact in the isolated 1,3-polyazulene. As-formed PAz films were insoluble in common organic solvents. To the best of our knowledge, this is the first report on the electrosyntheses of freestanding PAz films in BFEE. [Copyright &y& Elsevier]

Abstract: A novel photochromic diarylethene, 1,2-bis{2-ethyl-5-[2-(1,3-dioxolane)]-3-thienyl}perfluorocyclopentene (BEDTP), was synthesized and its structure was determined by single-crystal X-ray diffraction analysis. Its photochromic and fluorescent properties were also investigated. The results showed that this compound exhibited reversible photochromism, changing from colorless to magenta after irradiation with UV light both in solution and in the crystalline phase. In hexane solution, the open-ring isomer of BEDTP exhibited relatively strong fluorescence at 400nm when excited at 282nm. The fluorescence intensity decreased along with the photochromism upon irradiation with 254nm light and its closed-ring isomer showed almost no fluorescence. [Copyright &y& Elsevier]

Abstract: Photochromic diarylethene, 1,2-bis[2-methyl-5-(3-fluorophenyl)-3-thienyl] perfluorocylcopentene (1a), was synthesized. The compound showed good photochromic reactions both in solution and in PMMA matrix by photo-irradiation. Using the diarylethene 1b/PMMA film as recording medium and a He–Ne laser for recording and readout, four types of polarization holographic optical recording were accomplished for the first time. The results show that the orthogonal circular polarization recording is the best method for holographic optical recording when the target photochromic diarylethene is used as recording material. [Copyright &y& Elsevier]

Abstract: We had accomplished recording and readout of bit patterns by two-photon 3D optical storage technology using a new photochromic diarylethene, 1,2-bis(2-methyl-5-methylene-n-butylamido-thien-3-yl) perfluorocyclopentene (BMMBTP), as memory medium. The photochromic reaction, both in solution and in poly(methyl methacrylate) (PMMA) amorphous film, and fluorescence property of BMMBTP were investigated. [Copyright &y& Elsevier]

Abstract: High quality free-standing poly(9-fluorenone) (PFO) films were synthesized electrochemically by direct anodic oxidation of 9-fluorenone (FO) in pure boron trifluoride diethyl etherate (BFEE). The oxidation potential of FO in this medium was measured to be only 1.48V versus SCE, which was greatly lower than that determined in CH2Cl2 +0.1moll−1 Bu4NBF4 (2.21V versus SCE). PFO films obtained from BFEE showed good electrochemical behavior, good thermal stability with electrical conductivity of 7.8×10−3 Scm−1, indicating that BFEE was a better medium than CH2Cl2 for the electrosyntheses of PFO films. Structural studies showed that the polymerization of FO ring occurred at 2,7-position. As-formed PFO films can be partly dissolved in acetone and tetrahydrofuran (THF). Fluorescent spectral studies indicate that PFO is a good blue light emitter. To the best of our knowledge, this is the first report on the electrosyntheses of free-standing PFO films. [Copyright &y& Elsevier]

Abstract: Photochromic diarylethenes bearing fluorine atoms at the ortho-, meta-, or para-position of both terminal phenyl rings have been synthesized. Effect of the substituent positions on their optoelectronic properties, including photochromism in solution, fluorescence, and electrochemical properties were investigated for the first time. The results indicated that the position of the fluorine substituent had remarkable impacts on molar absorption coefficient of the closed-ring forms of diarylethenes, quantum yields of the cyclization and cycloreversion reactions, fluorescence intensity, as well as the oxidation potential. [Copyright &y& Elsevier]

Abstract: Poly(3,4-ethylenedioxythiophene) (PEDOT) films were synthesized electrochemically by direct anodic oxidation of 3,4-ethylenedioxythiophene (EDOT) at relatively low monomer concentration (0.005–0.01molL−1) in aqueous solution containing green nonionic sugar-based surfactant N-dodecyl-β-d-maltoside (DM), which has good biocompatibility and biodegradability. The moderate interaction between DM through the hydroxy groups and EDOT monomer led to the decrease of monomer oxidation onset. Different surfactants, such as anionic sodium dodecylbenzenesulfate (SDBS), nonionic triton X-100 (TX100), were also tested for comparison. As-formed PEDOT films were characterized electrochemically and spectroscopically using FTIR and UV–visible techniques. PEDOT nano-materials with good thermal stability and conductivity of 26.2Scm−1 can be synthesized in water-DM micellar solution, which can be proved by the results of scanning electron microscopy (SEM). PEDOT prepared from water-DM media with good biocompatibility can be a good candidate for application in biosensors. [Copyright &y& Elsevier]

[Display omitted] • A porous poplar flower-like PEDOT-MeOH/PEG/WS 2 composite was fabricated. • The PEDOT-MeOH/PEG/WS 2 showed a high capacitance of 461.5 mF cm−2 at 5 mV s−1. • The device presented a specific energy of 8.72 × 103 μWh cm−2 at 2.62 × 105 μW cm−2. • The capacitive retention was 83.6% after 5000 charge-discharge cycles. The morphology of electrode material is generally critical to affecting their electrochemical performance. Here, a porous poplar flower-like PEDOT-MeOH/PEG/WS 2 hybrid material is successfully prepared using a simply co-electrodeposition method. With the assistance of poly(ethylene glycol) (PEG), the chemically exfoliated WS 2 nanosheets are doped into poly(hydroxymethyl-3,4-ethylenedioxythiophene) (PEDOT-MeOH) film. The formation of a porous poplar flower-like PEDOT-MeOH/PEG/WS 2 composite is proved by scanning electron microscopy, transmission electron microscopy, infrared spectra, energy-dispersive X-ray spectrometry and X-ray photoelectron spectroscopy. The maximum capacitance of the composite reaches 461.5 mF cm−2, which is 1.6 times greater than that of PEDOT-MeOH/PEG film. As-fabricated PEDOT-MeOH/PEG/WS 2 composite can keep 85.8% of the initial areal capacitance after 5000 cycles. Additionally, PEDOT-MeOH/PEG/WS 2 -based symmetrical supercapacitor presents a capacitive capacity of 62.7 mF cm−2 at 0.5 mA cm−2, specific energy of 8.72 × 103 μWh cm−2 at 2.62 × 105 μW cm−2, and capacitive retention of 83.3% after 5000 cycles with a 100% coulombic efficiency. The capacitance improvement of PEDOT-MeOH/PEG/WS 2 composite is closely related to porous poplar flower-like structure as well as the cooperation-enhancing effect between PEDOT-MeOH and WS 2. These results imply that PEDOT-MeOH/PEG/WS 2 composite will have great potential application in the field of the energy storage. [ABSTRACT FROM AUTHOR]

Rational design of fiber-shaped gas sensors with both excellent mechanical properties and sensing performance is of great significance for boosting future portable and wearable sensing electronics, however, it is still a challenge. Herein, we develop a novel fiber-shaped hydrogen (H 2) sensor by directly electrochemically growing palladium (Pd) sensing layer on conductive poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) fiber electrode. This approach produces free-standing functional fiber (PEDOT:PSS@Pd) with promising mechanical features of flexibility, light weight, knittability and high mechanical strength, and good H 2 sensing performance at room temperature. The PEDOT:PSS@Pd fiber sensor exhibits short response time of 34 (± 6) s@1% and 19 (± 4) s@4% H 2 and excellent cycling stability. In addition, the fiber sensor remains good sensing behavior under different mechanical bending states, showing potential for constructing wearable sensor devices for timely H 2 leak detection. Therefore, this work has provided a smart design strategy of fiber-based gas sensor, offering an effective sensing platform and is believed to stimulate the development of wearable electronics. [Display omitted] • A novel flexible fiber-shaped H 2 sensor (PEDOT:PSS@Pd) was designed. • The fiber sensor possesses excellent mechanical properties and substrate-free. • The sensor displays short response time (19 ± 4 s@4% H 2) at room temperature. • The fiber sensor exhibits steady H 2 sensing behavior at different bending states. [ABSTRACT FROM AUTHOR]