Conductive Polyaniline Research Articles

Preparation of a self-healing polyaniline-based gel and its application as a healable all-in-one capacitor

Polyaniline (PANI) prepared by polymerization methods is fragile due to its rigid structure. The preparation of PANI with desirable flexible performance and good ductility still remains a challenge. Here, a self-healing conductive polyacrylamide (PAM)/PANI gel (PPG) with sandwich structure is reported. The surface of PPG is composed of interpenetrating network of conductive PANI and flexible PAM through dynamic hydrogen bonds. PPG exhibits outstanding mechanical property with remarkable tensile strength (0.342 MPa) and elongation at break (277%), as well as efficient self-healing ability. Thus, PPG makes up for the flexible requirement of PANI and can be developed for potential application as an all-in-one solid-state capacitor with high performance. The flexible solid-state capacitor delivers a large capacitance (473 mF/cm2) and extraordinary self-healing performance. This work may provide new insight into the design of flexible PANI and a practical strategy to fabricate mechanically and electrochemically robust gel.

Asymmetric Charged Conductive Porous Films for Electricity Generation from Water Droplets via Capillary Infiltrating.

Hydrovoltaic devices are proposed as an alternative way to directly generate electricity due to the ubiquity of water and its interaction with specific porous structures. At present, the output power density of the reported device is limited by its low current density arising from the low surface charge density and inferior charge transport capability of the active materials. In this work, an asymmetric structure consisting of positively charged conductive polyaniline (PANI) and negatively charged Ti3C2TX MXene is proposed to build a hydrovoltaic device to achieve high conductivity and surface charge density simultaneously. An extra polyvinyl alcohol layer is utilized between PANI and MXene to reserve the asymmetric structure and maintain a constant voltage output. As a result, a peak current density of 1.8 mA/cm2 is achieved, which is 18 times higher than the previous peak current density of the device with an inert electrode. Our work of incorporating an asymmetric structure provides an alternative way to target high-efficiency hydrovoltaic devices with a large current density.

Polysketch Pen: Drawing from Materials Chemistry to Create Interactive Art and Sensors Using a Polyaniline Ink

Writing instruments, such as pens, are ubiquitous in the classroom, but their functionality is largely for one purpose: they are used to represent ideas and record information on paper. However, by replacing the conventional ink in a pen with easy-to-synthesize conducting polymer-based inks, it is possible to change a simple writing utensil into a materials processing tool that can create circuits, sensors, and potentially other optoelectronic devices. The Polysketch pen is a modified ballpoint pen that contains a conductive polyaniline ink that can be synthesized safely by high school and undergraduate students in a 1–3 hour laboratory setting. The synthesis and formulation of the ink and the construction of the pen expose students to nanomaterial synthesis, chemical/material purification, and functional design with a specific goal: producing an appropriately viscous, fast-drying ink with a suitable loading level of polyaniline for conductive properties. The Polysketch pen leaves conductive traces on paper, which can be used to draw simple circuits or construct sensors responding to mechanical strains or ambient chemical species. This activity has the objective of introducing materials-relevant polymer synthesis into high school and undergraduate laboratories while introducing concepts in conductive polymers such as doping/dedoping and percolation in conductive networks. The activity is constructed such that students have the opportunity to explore processing–structure–properties–performance relationships by optimizing ink formulation. Most importantly, students will ultimately arrive at a tangible, versatile product and tool that enables them to explore other types of interactive devices and art to “trace a line of their creation”.

A novel multi-dimension inorganic–organic hybrid aerogel and its electrochemical behavior

Halloysite nanotubes (HNTs) were widely concerned in the research of electrode materials for supercapacitors because it had many advantages, such as abundant natural reserves, non-toxic, large specific surface area, and so on. The zero-dimensional Fe3O4 nanoparticles loaded onto the surface of one-dimensional HNTs (HNTs-O) could give HNT’s excellent electrical properties and improve the specific capacitance. In our previous study, the HNTs were connected into three-dimensional interconnected nano-network (HCAs) by electrostatic interaction. It was found interesting phenomena in load transfer ability and increasing the specific surface area. Based on our previous studies, in this study, HNTs-O was compounded with the three-dimensional HCAs to prepare the composite aerogel (CA-O). The organic–inorganic hybrid aerogels (CA-OP) were prepared by loading conductive polymer polyaniline (PANI) onto the composite aerogel surface to form a two-dimensional PANI. The synergistic effect of inorganic HNTs-O and organic PANI had improved the conductivity and electrical properties of CA-OP. The results of the scanning electron microscope, Fourier transform infrared, N2 adsorption–desorption, stress–strain tests, and so on showed that the composite was successfully prepared and had the acceptable performance in specific surface area and mechanical properties. Cyclic voltammetry, electrochemical impedance spectroscopy, and other electrochemical tests suggested that the organic–inorganic hybrid aerogel had large capacitance and exciting cycle performance.

Electrical Conductivity and Antenna Properties of Polyaniline filled GNPs Nanocomposites

This study was conducted to investigate the potential of utilizing conductive polymer nanocomposite for flexible type antenna application. The polyaniline (PANI) filled with graphene nanoplatelets (GNPs) nanocomposites were synthesized by an oxidative aniline polymerization in an acidic medium. The PANI/GNPs nanocomposites were then characterized by using various spectroscopy and imaging tools. It was found that the strong interaction between PANI macromolecules and GNPs flakes is caused by the strong ?-? conjugation between them, as validated by an increase of Id/Ig ratio of PANI/GNPs nanocomposites. As a result, it established a three-fold improvement for the electrical conductivity of PANI/GNPs nanocomposites, due to the larger amount of charge carrier transport at higher GNPs nanofiller loadings (1.00 wt.%). Later, the PANI/GNPs nanocomposites powder was applied to the cotton fabric by integrating it with a rubber paint slurry. Electrical conductivity, antenna gain, return loss, and radiation pattern of the antenna were reported. It was found that PANI/GNPs flexible textile antenna possessed a constant gain of 4.1809 dB, return loss at -13.154 dB, and radiation pattern which operated at 10.36 GHz for 100% improvement of electrical conductivity, in comparison with unfilled PANI. From these findings, it can be said that the development of wearable textile antenna utilizing PANI/GNPs nanocomposites on the cotton fabric as flexible radiation patch, has great potential for wireless communication purposes.

Synthesis, and Study the Electrical Properties of Conductive (PVA:PANI)/CuI Blend Composite

PVA:PANI/CuI thin film composites were prepared by adding (CuI) nanoparticles to the blend of the poly vinyl alcohol and conductive polyaniline with various concentrations (0, 2, 4, 6, and 8% wt) using the casting method technique on glass substrate at room temperature. The type, concentration of charge carriers, and Hall mobility (µH) had estimated from Hall measurement and shown that the polymer thin films before additive of CuI nanoparticles were positive Hall coefficient (P-type). While the polymer thin films for all concentration of CuI nanoparticles have negative Hall coefficient (n-type) except of sample with concentration 6 %wt was remained positive Hall coefficient (P-type). In D.C measurement, increasing of temperature value leads to reduce the electrical resistance, also the D.C conductivity of the thin film composites rises with increasing additive concentration of CuI nanoparticles. The activation energy values for PVA:PANI polymer blend composites decreased when the concentration of CuI nanoparticles increased. Alternating electrical conductivity (σac) increases when the frequency of all samples increases. While the alternating electrical conductivity (σac) remains constant at very low frequency.

Polymerization of polyaniline under various concentrations of ammonium peroxydisulfate and hydrochloric acid by ultrasonic irradiation

AbstractEffects of various molar ratios of monomer (aniline), oxidant (ammonium peroxydisulfate), and dopant (hydrochloric acid) on the polymerization of polyaniline (PANI) were investigated using direct ultrasonic irradiation technique. The effects of varying molar ratio of dopant and oxidant on the structural stability, morphology, and electrical conductivity of the prepared PANI were studied. Firstly, a scheme derived from electrical conductivity point of view, by varying the molar ratio of ammonium peroxydisulfate (APS). As the molar ratio of APS to aniline (ANI) varied from 0.1 to 1.25, the conductivity of PANI reached a maximum of 0.24 S/cm at a ratio of 1. Thereafter, by fixing the optimized molar ratio of APS and aniline the molar ratio of hydrochloric acid (HCl) was varied. The conductivity of PANI increased with an increase of HCl concentration and reached a maximum of 0.5 S/cm at an HCl concentration of 2 M. Finally, the formation mechanism for polymerization of PANI were discussed using Fourier transform infrared spectra, ultraviolet–visible spectra, nuclear magnetic resonance spectroscopy, and X‐ray diffraction spectroscopy. The final product is in protonated form, possessing structural stability and electrically conductive.

Leather Solid Waste/Poly(vinyl alcohol)/Polyaniline Aerogel with Mechanical Robustness, Flame Retardancy, and Enhanced Electromagnetic Interference Shielding.

Renewable biobased aerogels display a promising potential to fulfill the surging demand in various industrial sectors. However, its inherent low mechanical robustness, flammability, and lack of functionality are still huge obstacles in its practical application. Herein, a novel integrated leather solid waste (LSW)/poly(vinyl alcohol) (PVA)/polyaniline (PANI) aerogel with high mechanical robustness, flame retardancy, and electromagnetic interference (EMI) shielding performance was successfully prepared. Amino carboxyl groups in LSW could be effectively exposed by solid-state shear milling (S3 M) technology to form strong hydrogen-bond interactions with the PVA molecular chains. This led to a change in the compressive strength and the temperature of the initial dimensional change to 15.6 MPa and 112.7 °C at a thickness of 2.5 cm, respectively. Moreover, LSW contains a large number of N elements, which ensures a nitrogen-based flame-retardant mechanism and increase in the limit oxygen index value of LSW/PVA aerogel to 32.0% at a thickness of 2.5 mm. Notably, by the cyclic coating method, a conductive PANI layer could be polymerized on the surface of LSW/PVA aerogel, which led to the construction of a sandwich structure with impressive EMI shielding capability. The EMI shielding effectiveness (SE) reached more than 40 dB, and the specific shielding effectiveness (SSE) reached 73.0 dB cm3 g-1. The inherent dipoles in collagen fibers and the conductive PANI synergistically produced an internal multiple reflection and absorption mechanism. The comprehensive performance of LSW/PVA/PANI aerogel not only demonstrates a new strategy to recycle LSW in a more value-added way but also sheds some more light on the development of biomass aerogels with high-performance, environmentally friendly, and cost-effective properties.

Preparation of proton block and highly conductive AEM by creating PANI dominated and hydrophobicity ion channels for sulfuric acid enrichment

AbstractElectrodialysis is widely used to separate and concentrate sulfuric acid from industrial wastewater. Nevertheless, owing to the proton leakage of anion‐exchange membrane (AEM), the concentration of recycled sulfuric acid is typically less than 20 wt.%. What is more, the restraining of proton leakage would sacrifice the conductivity of membrane, leading to the increasing of energy consumption (EC). In this work, a proton block and highly conductive polyaniline (PANI)/polyvinylidene fluoride (PVDF) membrane were prepared by creating PANI dominated and hydrophobicity ion channels through etching. The variations of solubility, structure, and electrical performance of membrane during etching process were investigated. As a result, the electrical performance of membrane, especially for the conductivity, was significantly improved owning to the formation of PANI dominated ion channels and spaces. Meanwhile, even the porosity and water content of etched membrane were improved, the anions were mainly migrated through molecular chains of PANI; the protons were still blocked by the hydrophobic pores. Further, the etched membranes with different porosities were used to enrich sulfuric acid (1 wt.%) through electrodialysis. As a result, the proton leakage was proved to be the major limitative factor of acid solution enrichment. By using the optimal etched membrane, concentrated acid (41 wt.%) was obtained with a less energy consume (EC), compared with commercial AEM.

Synthesis of ternary core-shell structured ZnOC@CoC@PAN for high-performance electromagnetic absorption

A novel ternary core-shell structured ZnOC@CoC@PAN as an electromagnetic wave (EMW) absorber was successfully fabricated by calcining precursor ZIF-8@ZIF-67 and covering the product with conductive polyaniline (PAN). The multicomponent core-shell structure and the conductive polymer coating were conducive to increasing the dielectric loss, magnetic loss, interfacial polarization, and conductivity loss to dissipate EMW energy. Adjusting the amount of aniline gave ZnOC@CoC@PAN-0.5, which had excellent EMW absorption performance. The minimum reflection loss ( RL min ) was −50.62 dB at 13.66 GHz and the effective absorption bandwidth (RL < −10 dB) reached 5.86 GHz with a matching thickness of 2.05 mm. This novel core-shell structured ZnOC@CoC@PAN has great potential in the field of EMW absorption. • ZnOC@CoC@PAN has a unique ternary shell structure, which can construct multiple interfaces to enhance interfacial polarization. • The RL min is −50.62 dB at 13.66 GHz and the effective absorption bandwidth is up to 5.86 GHz with the matching thickness of 2.05 mm. • The mechanism of absorption is explored from the microscopic perspective.

Controlled chemical oxidative polymerization of conductive polyaniline with excellent pseudocapacitive properties

Nowadays, the application of supercapacitor in energy storage is more and more extensive, and the selection and preparation of electrode material have become a formidable challenge. Polyaniline (PANI) has turned into one of the most hopeful conductive polymers due to its superior properties. In this article, conductive polyaniline was synthesized by chemical oxidative polymerization to acquire excellent electrochemical properties. Scanning electron microscopy (SEM), X-ray diffraction (XRD), cyclic voltammetry (CV), and galvanostatic charge–discharge (GCD) measurements were adopted to explore the microstructure and energy storage capacity. The PANI is in coralline network morphology with high surface area, which can supply more active sites during charge and discharge process. The PANI shows a high specific capacitance value of 790 F/g, and the highest conductivity is 15.5 S/cm. The consequence shows that PANI synthesized under certain conditions has a promising feasibility for applications in high-performance supercapacitor electrode material.

A Conductive Hydrophobic Polyaniline Sandwiched Polyvinylidene Fluoride Membrane for Early Detection of Surfactant-Induced Wetting in Membrane Distillation Using Impedance

Wetting of hydrophobic membranes is considered to be one of the major limitations that must be overcome to further the development of membrane distillation technology. Low surface tension liquids c...

Engineering of new hydrogel beads based conducting polymers: Metal-free catalysis for highly organic pollutants degradation

Engineering of new heterogeneous metal-free catalysts is of great importance for persulfate activation. Herein, Innovative conductive polymers Polyaniline (PANI) and Polypyrrole (PPy) were used as promising catalysts for PS activation to effectively degrade organic pollutants. In fact, PANI and PPy can provide the necessary electron transfer based on nitrogen atoms located in the conjugated chains compared to their counterparts in the defective sites. In addition, PANI and PPy were immobilized inside membrane formed by cross linking alginate biopolymer by divalent calcium ions, in order to develop a new stable hydrogel beads catalyst. The prepared hydrogels-activated PS process could maintain excellent catalytic properties, mitigate catalysts deactivation, increased chemical stability and offer hope for their application in the industrial scale. The radical scavenging experiments monitored by the electron paramagnetic resonance and functional theory calculations, indicated the role of the PANI and PPy conjugated chains and the nature of the reaction pathways.

A Nanocomposite Containing Carbon Nano‐onions and Polyaniline Nanotubes as a Novel Electrode Material for Electrochemical Sensing of Daidzein

AbstractGlassy carbon electrode (GCE) were modified with nanocomposites containing conductive polyaniline nanotubes (PANInt) and carbon nano‐onions (CNOs). Herein we report a simple and sensitive way for daidzein (DA) determination at concentrations between 1 and 10 μM by linear sweep voltammetry using GCE/PANInt/CNOs system. The DA electrochemical behavior was examined in two buffer environments (pH 7.5 and 4.5) using electrodes modified with the oxidized CNOs or their derivatives containing carboxyl and benzylamino functional groups. The direct electrooxidation of DA was observed at +0.65 V and +0.8 V at pH 7.5 and at +0.7 V and +1.1 V vs. Ag/AgCl at pH 4.5.

Cobalt ion redox and conductive polymers boosted the photocatalytic activity of the graphite carbon nitride–Co3O4 Z-scheme heterostructure

The enhanced photocatalytic hydrogen evolution performance of g-C3N4–Co3O4 2D–1D Z-scheme heterojunctions was achieved through the synergistic effect of the cobalt ion redox, conductive polyaniline, and a Co3O4 nanobelt.

Conductive polyaniline-mediated efficient electron transfer in Z-scheme photocatalysts for enhanced overall water splitting.

Here, we demonstrate that conductive polyaniline (PANI) can function as a solid redox mediator to efficiently shuttle photogenerated electrons from BiVO4 to Ru/SrTiO3:Rh, thus greatly promoting the separation of electrons and holes and nearly quadrupling the overall water splitting activity under visible light irradiation (λ ≥ 420 nm).

Polyaniline-fly ash nanocomposites synthesized via emulsion polymerization: Physicochemical, thermal and dielectric properties

The polyaniline (PANI)/nano-fly ash composites were synthesized by Inverted emulsion polymerization technique. The FTIR spectrum of PANI/nano-fly ash composite (50/50) shows the vibrational bands due to N–Hstretching (2165 cm−1), quinoid (1517 cm−1) and benzenoid ring stretching (1354 cm−1), etc. The UV–Visible absorption shows an absorption peak at 267 and 374 nm for PANI/nano-fly ash composite. Raman spectrum of composite shows peaks at 1635, 1339, 1179, 829, 569, 414 and 200 cm−1. The conductivity of pure polyaniline was decreased as a result of the addition of nano fly ash. X-ray diffraction of the composite shows two crystalline peaks at 20.9° and 26.2° (2Θ). The stability of pure PANI is enhanced by the incorporation of nano -fly ash. The coating of polyaniline on nano-fly ash has been confirmed by FESEM pictures. The AC conductivity was explained using the hopping model. The dielectric constant decreases as the frequency increases, it was explained by using Maxwell–Wagner polarization theory.

Enhanced electrical and thermal properties of semi-conductive PANI-CNCs with surface modified CNCs.

Cellulose nanocrystals (CNCs) are the most commonly used natural polymers for biomaterial synthesis. However, their low dispersibility, conductivity, and poor compatibility with the hydrophobic matrix hinder their potential applications. Therefore, we grafted sulfate half-ester and carboxylic functional groups onto CNC surfaces (S-CNC and C-CNC) to overcome these shortcomings. The effect of the dopants, surfactant ratios, and properties of CNCs on the thermal stability, conductivity, and surface morphology of polyaniline (PANI)-doped CNC nanocomposites were investigated through emulsion and in situ polymerization. The higher electrical conductivity and well-dispersed morphology of SCNC–PANI30 (1.1 × 10−2 S cm−1) but lower thermal stability than that of CCNC–PANI30 (T0: 189 °C) nanocomposites are highly related to dispersibility of S-CNCs. However, after 4-dodecylbenzenesulfonic acid (DBSA) was added, the conductivity and thermal stability of SCNC/PANI increased up to 2.5 × 10−1 S cm−1 and 192 °C with almost no particle aggregation because of the increase in charge dispersion. The proposed biodegradable, renewable, and surface-modified S-CNC and C-CNC can be used in high-thermal-stability applications such as food packaging, optical films, reinforcement fillers, flexible semiconductors, and electromagnetic materials.

Development of a Protein Biochip Platform for Parkinson's Disease.

Parkinson's disease (PD) is a complex neurodegenerative disorder, characterized by severe motor symptoms which lead to progressive weakness of motor function caused by prominent loss of dopamine-secreting neurons within the substantia nigra. Compelling neuropathological evidence reveals the accumulation of insoluble protein aggregates, such as α-synuclein and tau, which are important hallmarks of the disease. Protein biochips have great potential to be powerful tools for clinical diagnostics, whereas novel sensing methods implementing biosensors for protein quantification in body fluids are highly required. Herein, the development of a device using a thin film of conductive polymer acid-doped polyaniline that can detect specific biomolecules is examined. The polymer is shown to change conductivity in the presence of proteins, so this direct chemical to electric transduction can be used to quantify concentration alterations. The fabrication of such a device is proposed, so that it can be implemented in rapid screening tests as part of an integrated holistic point-of-care diagnostics model that brings together a multidisciplinary healthcare team of PD experts.

Enhancement of Electrical Conductivity of Polyaniline Synthesized by using Carbon Nanofiber

Carbon nanofiber (CNF) is a very useful additive for improving the performance of polymer matrix composites, but the performance has sometimes been interrupted by limits appear within composite processing. Recently, CNF based polymer composites are intensely considered as promising materials in many application fields, such as electrical devices, electrode materials for batteries, supercapacitors, sensors, etc. Among these, the electrical conductivity is always the first priority need to be considered. Polyaniline (PANI) and PANI-CNF composites are synthesized by chemical oxidative polymerization of aniline monomers in acidic media. The electrical conductivity of PANI-CNF composites were found varies with the degree of amount of CNF under the effect of multiple factors such as the concentration of aniline monomer, reaction media, oxidant, reaction temperature, reaction time, etc. The maximum electrical conductivity was found 3.7131 S/cm of the PANI-CNF composite coming from the polymerization of aniline with 0.05 g CNF. The results of the synthesis also demonstrated that CNF can be an effective material to prepare electrically conducting polymer composites with ordered nanostructures.