Condensing Vapor Phase Polymerization (CVPP) of Electrochemically Capacitive and Stable Polypyrrole Microtubes

We introduce a novel condensing vapor phase polymerization (CVPP) strategy for depositing microtubes of the conducting polymer polypyrrole; these serve as one-dimensional hollow microstructures for storing electrochemical energy. In CVPP, water droplets are structure-directing templates for polypyrrole microtubes. Water vapor condensation and polymerization occur simultaneously-conformal coatings of microtubes deposit on porous substrates such as hard carbon fiber paper or glass fiber filter paper. A mechanistic evolution of the microtubular morphology is proposed and tested based on the mass transport of water and monomer vapors as well as on the reaction stoichiometry. A coating of PPy microtubes is characterized by a high reversible capacitance of 342 F g^-1 at 5 mV s^-1 throughout 5000 cycles of cyclic voltammetry and a low sheet resistance of 70.2 Ω □^-1. The open tubular structure is controlled in situ during synthesis and leads to electrodes that exhibit electrochemical stability at high scanning rates up to 250 mV s^-1 retaining all stored charge, even after extensive cycling at 25 mV s^-1.

Electrocatalytic Performance of Chemically Synthesized PIn-Au-SGO Composite toward Mediated Biofuel Cell Anode

The proposed work intended to make an intellectual contribution to the domain of green nanotechnology which emphasizes the chemical synthesis of a conducting nanocomposite based on the incorporation of gold nanoparticles (Au) into the redox matrix of polyindole (PIn) along with the subsequent improvement in the overall properties of the composite by the addition of sulfonated graphene oxide (SGO). The bioanode was developed by the deposition of the PIn-Au-SGO nanocomposite with subsequent immobilization of ferritin (Frt) and glucose oxidase (GOx) on the glassy carbon electrode (GC). The successful application of the PIn-Au-SGO nanocomposite toward the development of a ferritin-mediated glucose biofuel cell anode was studied by the electrochemical characterization of the constructed bioanode (GC-PIn-Au-SGO/Frt/GOx) for the bioelectrocatalytic oxidation of glucose. The maximum current density obtained by the modified bioanode was found to be 17.8 mA cm⁻² at the limiting glucose concentration of 50 mM in 0.1 M K₄Fe(CN)₆ at a scan rate of 100 mVs⁻¹. The lifetime of the concerned bioelectrode when stored at 4 °C was estimated to be 53 days approximately. The appreciable results of the structural and electrochemical characterization of the PIn-Au-SGO based bioelectrode reveal its potential applications exclusively in implantable medical devices.

Electropolymerisation of N-Ethylanilinium Trifluoroacetate Ionic Liquid into Poly(N-Ethylaniline) and Control of its Morphology

In this paper, the electropolymerisation of pre-synthesised N-ethylanilinium trifluoroacetate, a protic ionic liquid (PIL), was carried out. The PIL served as the monomer precursor, solvent, and supporting electrolyte for the polymerisation process, and no additional acid was required due to the protic nature of the PIL. Two different morphologies of the poly(N-ethylaniline) were achieved by using different electropolymerisation approaches and the resultant films were soluble in the PIL precursor as well as a wide range of organic solvents. The use of anilinium based PILs, as polymerisation precursors, promises a greener approach for the production of polyanilines, as well as highly processable polymers.

Electrochemical Tailoring of Fibrous Polyaniline and Electroless Decoration with Gold and Platinum Nanoparticles

Presented in this work is a facile and quick electrochemical method for controlling the morphology of thick polyaniline (PANi) films, without the use of templates. By stepping the polymerization potential from high voltages to a lower (or series of lower) voltage(s), we successfully controlled the morphology of the polymer, and fibrous structures, unique to each potential step, were achieved. In addition, the resultant film was tested electrochemically for its viability as an electrode material for flexible batteries and supercapacitors. Furthermore, the PANi film was decorated with gold and platinum nanoparticles via an electroless deposition process for possible electrocatalytic applications, whereby the oxidation of hydrazine at the composite was investigated.

Polymer-Based Organic Batteries

The storage of electric energy is of ever growing importance for our modern, technology-based society, and novel battery systems are in the focus of research. The substitution of conventional metals as redox-active material by organic materials offers a promising alternative for the next generation of rechargeable batteries since these organic batteries are excelling in charging speed and cycling stability. This review provides a comprehensive overview of these systems and discusses the numerous classes of organic, polymer-based active materials as well as auxiliary components of the battery, like additives or electrolytes. Moreover, a definition of important cell characteristics and an introduction to selected characterization techniques is provided, completed by the discussion of potential socio-economic impacts.

Toward Uniformly Dispersed Battery Electrode Composite Materials: Characteristics and Performance

Battery electrodes are complex mesoscale systems comprised of electroactive components, conductive additives, and binders. In this report, methods for processing electrodes with dispersion of the components are described. To investigate the degree of material dispersion, a spin-coating technique was adopted to provide a thin, uniform layer that enabled observation of the morphology. Distinct differences in the distribution profile of the electrode components arising from individual materials physical affinities were readily identified. Hansen solubility parameter (HSP) analysis revealed pertinent surface interactions associated with materials dispersivity. Further studies demonstrated that HSPs can provide an effective strategy to identify surface modification approaches for improved dispersions of battery electrode materials. Specifically, introduction of surfactantlike functionality such as oleic acid (OA) capping and P3HT-conjugated polymer wrapping on the surface of nanomaterials significantly enhanced material dispersity over the composite electrode. The approach to the surface treatment on the basis of HSP study can facilitate design of composite electrodes with uniformly dispersed morphology and may contribute to enhancing their electrical and electrochemical behaviors. The conductivity of the composites and their electrochemical performance was also characterized. The study illustrates the importance of considering electronic conductivity, electron transfer, and ion transport in the design of environments incorporating active nanomaterials.

A graphene supported polyimide nanocomposite as a high performance organic cathode material for lithium ion batteries

Organic electrode materials are promising and future candidates for applications such as cathode in green lithium-ion batteries (LIBs).

Wood-derived biochar supported polypyrrole nanoparticles as a free-standing supercapacitor electrode

Paulownia wood processing residues were adopted as both a template and precursor for the synthesis of a wood-derived biochar/polypyrrole composite, serving as a free-standing and binder-free supercapacitor electrode.

High-throughput approach for the identification of anilinium-based ionic liquids that are suitable for electropolymerisation

We report the synthesis of new protic ionic liquids (PILs) based on aniline derivatives and the use of high-throughput (HT) techniques to screen possible candidates. In this work, a simple HT method was applied to rapidly screen different aniline derivatives against different acids in order to identify possible combinations that produce PILs. This was followed by repeating the HT process with a Chemspeed robotic synthesis platform for more accurate results. One of the successful combinations were then chosen to be synthesised on a larger scale for further analysis. The new PILs are of interest to the fields of ionic liquids, energy storage and especially, conducting polymers as they serve as solvents, electrolytes and monomers at the same time for possible electropolymerisation (i.e. a self-contained polymer precursor).

Simultaneous electronic and ionic conduction in ionic liquid imbibed polyacetylene-like conjugated polymer films

Electron and ion conducting polymer film prepared by hydroiodic acid catalyzed dehydration of poly(vinyl alcohol) and 1-propyl-3-methylimidazolium iodide blend.

Conducting polymers and their inorganic composites for advanced Li-ion batteries: a review

Conducting polymers are promising materials for organic–inorganic composites in lithium-ion batteries due to electrical conductivity and high coulombic efficiency, and are able to be cycled hundreds or thousands of times with only small degradation.

Lithium doped polyaniline and its composites with LiFePO4 and LiMn2O4-prospective cathode active materials for environment friendly and flexible Li-ion battery applications

The present work is an attempt to realize Li-ion cells using Li-substituted polyaniline (PANI) and its composites with LiFePO₄ and LiMn₂O₄ as cathodes, with flexibility in the cell design and the retention of capacity over long cycles.