Search

[Display omitted] Electrical bioadhesive interfaces (EBIs) are standing out in various applications, including medical diagnostics, prosthetic devices, rehabilitation, and human–machine interactions. Nonetheless, crafting a reliable and advanced EBI with comprehensive properties spanning electrochemical, electrical, mechanical, and self-healing capabilities remains a formidable challenge. Herein, we develop a self-healing EBI by thoughtfully integrating conducting polymer nanofibers and a typical bioadhesive within a robust hydrogel matrix. The accomplished EBI demonstrates extraordinary adhesion (lap shear strength of 197 kPa), exceptional electrical conductivity (2.18 S m−1), and outstanding self-healing performance. Taking advantage of these attributes, we integrated the EBI into flexible skin electrodes for surface electromyography (sEMG) signal recording from forearm muscles. The engineered skin electrodes exhibit robust adhesion to the skin even when sweating, rapid self-healing from damage, and seamless real-time signal recording with a higher signal-to-noise ratio (39 dB). Our EBI, along with its skin electrodes, offers a promising platform for tissue-device integration, health monitoring, and an array of bioelectronic applications. [ABSTRACT FROM AUTHOR]

[Display omitted] Improving the electrocatalytic performance by modulating the surface and interface electronic structure of noble metals is still a research hotspot in electrocatalysis. Herein, we prepared the heterogeneous catalyst based on the well-dispersed PdCu nanoalloy and the N -doped Ti 3 C 2 T x MXene support (PdCu/N-Ti 3 C 2 T x) via in situ growth of PdCu nanoparticles on the fantastic N-Ti 3 C 2 T x sheets. By exploring the electrocatalytic properties of ethanol oxidation reaction (EOR), the composition optimized Pd 1 Cu 1 /N-Ti 3 C 2 T x delivers higher mass activity/specific activity/intrinsic activity (2200.7 mA mg Pd -1/13.1 mA cm−2/2.2 s−1), anti-poisoning ability and stability than those of Pd/N-Ti 3 C 2 T x , Pd 1 Cu 1 /Ti 3 C 2 T x and commercial Pd/C, which can be attributed to the modified surface electronic features of Pd by the participation of Cu atoms and N-Ti 3 C 2 T x MXene, as well as the "metal-carrier" effect between the PdCu nanoalloy and N-Ti 3 C 2 T x heterogeneous interface. Furthermore, the conductivity of N-Ti 3 C 2 T x MXene can be improved by N -doping, and the abundant terminal groups (-O, –OH, -F and N) on the N-Ti 3 C 2 T x surface can promote the electron exchange between PdCu and N-Ti 3 C 2 T x. This work provides an effective strategy for engineering heterogeneous electrocatalysts for enhanced electrocatalytic EOR by adjusting the interfacial electronic structure of noble metals. [ABSTRACT FROM AUTHOR]

[Display omitted] • We develop a PEDOT-MeOH:PSS/PDA interface by a two-step electropolymerization method. • The prepared interface shows strong adhesion with 93% area retention after sonication for 20 min. • We further demonstrate the PEDOT-MeOH:PSS/PDA interface integrated on an ultrasmall Pt-Ir wire microelectrode with a diameter of only 10 μm. • The modified implantable neural microelectrodes display two orders of magnitude lower impedance than commercial products, and also superior long-term stability after 10,000,000 biphasic input pulse cycles. Conducting polymers are emerging as promising neural interfaces towards diverse applications such as deep brain stimulation due to their superior biocompatibility, electrical, and mechanical properties. However, existing conducting polymer-based neural interfaces still suffer from several challenges and limitations such as complex preparation procedures, weak interfacial adhesion, poor long-term fidelity and stability, and expensive microfabrication, significantly hindering their broad practical applications and marketization. Herein, we develop an adhesive and long-term stable conducting polymer neural interface by a simple two-step electropolymerization methodology, namely, the pre-polymerization of polydopamine (PDA) as an adhesive thin layer followed by electropolymerization of hydroxymethylated 3,4-ethylenedioxythiophene (EDOT-MeOH) with polystyrene sulfonate (PSS) to form stable interpenetrating PEDOT-MeOH:PSS/PDA networks. As-prepared PEDOT-MeOH:PSS/PDA interface exhibits remarkably improved interfacial adhesion against metallic electrodes, showing 93% area retention against vigorous sonication for 20 min, which is one of the best tenacious conducting polymer interfaces so far. Enabled by the simple methodology, we can facilely fabricate the PEDOT-MeOH:PSS/PDA interface onto ultrasmall Pt-Ir wire microelectrodes (diameter: 10 μm). The modified microelectrodes display two orders of magnitude lower impedance than commercial products, and also superior long-term stability to previous reports with high charge injection capacity retention up to 99.5% upon 10,000,000 biphasic input pulse cycles. With these findings, such a simple methodology, together with the fabricated high-performance and stable neural interface, can potentially provide a powerful tool for both advanced neuroscience researches and cutting-edge clinical applications like brain-controlled intelligence. [ABSTRACT FROM AUTHOR]

[Display omitted] In our work, poly(3,4-ethylenedioxythiophene) (PEDOT) granules supported Cu/Ni-doped Pd electrocatalysts (PdCu/PEDOT and PdNi/PEDOT) were synthesized for ethylene glycol (EG) oxidation in alkaline medium. The amorphous PEDOT granules as the catalyst supports provide plenty of attachment sites for PdCu and PdNi nanoparticles. The optimized Pd 1 Cu 3 /PEDOT and Pd 7 Ni 3 /PEDOT catalysts both perform superior mass-based activity, area-based activity and intrinsic activity for EG oxidation as compared to other control samples. Moreover, chronoamperometry and long-term cyclic voltammetry tests demonstrate that the Pd 1 Cu 3 /PEDOT catalyst performs optimal anti-poisoning capability and catalytic durability. The outstanding electrocatalytic performance can be attributed to the favourable dispersion of Pd 1 Cu 3 and Pd 7 Ni 3 nanoparticles on the PEDOT granules and the synergistic effects between Pd, Cu/Ni atoms and the electron-rich conjugated structure of PEDOT. In summary, this work synthesized two Pd/PEDOT-based electrocatalysts with promising catalytic application prospect in direct ethylene glycol fuel cell (DEGFC), which may provide some theoretical support for the design and synthesis of competent electrocatalysts for DEGFC. [ABSTRACT FROM AUTHOR]

[Display omitted] Herein, a ternary-nanocomposite Pd-polypyrrole/nitrogen-doped graphene (Pd-PPy/NGE) has been prepared facilely by the one-pot method. In simple terms, PPy was in-situ polymerized on the surface of NGE with PdCl 4 2- as the oxidant, and simultaneously Pd nanopaticles were loaded on the surface of PPy or embedded in PPy particles. The obtained Pd-PPy/NGE nanocomposite exhibits promising electrocatalytic properties toward the oxidation reaction of alcohols in alkaline medium. Especially, the optimized Pd-PPy/NGE (1:50) catalyst possesses mass activity of 2176.7, 1192.7 and 498.9 mA mg Pd -1 toward ethylene glycol, methanol and ethanol electrooxidation, respectively, which are 4.3, 6.7 and 2.9 times of those for commercial Pd/C catalyst. Moreover, the Pd-PPy/NGE (1:50) also shows higher anti-poisoning ability and operating stability than the Pd/C catalyst. The promising electrocatalytic performance of the Pd-PPy/NGE (1:50) for alcohols oxidation can be ascribed to the well dispersion of Pd nanoparticles, the porous and stable three dimentional structure of the composite, and the synergistic effect between different components. The structural randomness of the conducting polymer and the potential synergistic effect between the metal nanoparticles and various supports would provide broad development space for these composites as electrocatalysts in direct alcohol fuel cell. [ABSTRACT FROM AUTHOR]

Adjusting the assembly of EDOT monomers through different oxidants can improve the structure and electrochemical performance of PEDOT. [Display omitted] • Explored different initiators to induce monomer assembly. • High oxidation degree and long conjugated chain of PEDOT achieved by Fe(Tos) 3. • PEDOT/P(Fe(Tos) 3)-6 displayed high areal capacitance of 419 mF cm-2 at 1 mA cm-2. The development of poly(3,4-ethylenedioxythiophene) (PEDOT) with high specific capacitance is the key to pursuing high-performance supercapacitors, and the electrochemical properties of PEDOT are closely related to the oxidation degree and conjugated chain length of its molecular chain. In this work, the influences of various oxidants (FeCl 3 , Fe(Tos) 3 and MoCl 5) on the molecular chain structure and capacitive properties of PEDOT via vapor phase polymerization were systematically investigated. Fe(Tos) 3 can significantly improve the degree of oxidation and the length of the conjugated chain of PEDOT compared to FeCl 3 and MoCl 5 , enhancing the conductivity and providing more active sites for Faraday reaction. Therefore, the PEDOT/P(Fe(Tos) 3) electrode displays a considerable conductivity of 73 S cm-1, high areal capacitance (419 mF cm-2) and excellent electrochemical stability under the different bent state. Moreover, the conjugated structure strengthens the interaction between PEDOT chains, achieving good cycle stability. Therefore, Fe(Tos) 3 is an ideal oxidant for obtaining high-performance PEDOT electrode materials. [ABSTRACT FROM AUTHOR]

Electrochromic devices with low-cost, energy-saving advantages, and controllable color switching have gained widely attention. Yet, electrochromic materials are limited for smart window due to challenges such as difficulty freestanding, monotonous color change, slow switching capability, and low optical contrast. In this work, a freestanding copolymers based on Poly(N -vinylcarbazole) (PVK) and 3, 4-ethoxylenedioxythiophene (EDOT) are designed. The copolymer as-synthesized by the good secondary film-forming of PVK not only contains the freestanding property of PVK, but also possesses the excellent electrical and electrochemical properties of poly(3, 4-ethoxylenedioxythiophene) (PEDOT). The freestanding copolymer was used to create the multicolor: brown, dark brown, purple, and blue. A high optical contrast of up to 39.1% and a color efficiency of up to 107.00 cm 2C−1 prove a significant coloration and bleaching effect, which is satisfactory for the application of electrochromic devices. Further, an electrochromic device based on P(PVK- co -EDOT) as coloring materials is constructed. This work contributes new ideas into the design of electrochromic smart materials. [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]