Polyaniline Nanocomposite Films Research Articles

Preparation of novel flexible freestanding conducting polyaniline nanocomposite films using recent generation polycarboxylate ether

Novel flexible freestanding films of polyaniline–polycarboxylate ether nanocomposites (PAni–PCE NCs) were first synthesized effectively by a one-step in-situ polymerization of aniline in the presence of recent generation superplasticizer PCE as a polyanionic dopant cum film-forming agent. Various spectrochemical methods were used to characterize the molecular structures of the produced PAni–PCE NCs. In this work, PAni–PCE NCs show the lattice fringes structures by HR–TEM study for the first time. The electrical conductivity of flexible freestanding PAni–PCE nanocomposite films was measured using a four-probe method. The maximum conductivity was found in the range of 1.5 S cm−1 for PAni–PCE5 nanocomposite film. FT–IR results confirmed that PAni had been successfully doped or incorporated into the PCE matrix. The XRD pattern validated the crystalline nature of novel flexible freestanding PAni–PCE nanocomposite films. By increasing the concentration of PCE from 0.033 M to 0.165 M, the morphological transition from nanorods to nanosheets and nanoneedles was observed in the SEM image of the flexible freestanding PAni–PCE NCs film. From the TGA result, flexible freestanding PAni–PCE nanocomposite films showed higher thermal stability than pure PAni.

Improvement of the Uniformity and Electrical Properties of Polyaniline Nanocomposite Film by Addition of Auxiliary Gases during Atmospheric Pressure Plasma Polymerization.

The morphological and chemical properties of polyaniline (PANI) nanocomposite films after adding small amounts of auxiliary gases such as argon, nitrogen, and oxygen during atmospheric pressure (AP) plasma polymerization are investigated in detail. A separate gas-supply line for applying an auxiliary gas is added to the AP plasma polymerization system to avoid plasma instability due to the addition of auxiliary gas during polymerization. A small amount of neutral gas species in the plasma medium can reduce the reactivity of monomers hyperactivated by high plasma energy and prevent excessive crosslinking, thereby obtaining a uniform and regular PANI nanocomposite film. The addition of small amounts of argon or nitrogen during polymerization significantly improves the uniformity and regularity of PANI nanocomposite films, whereas the addition of oxygen weakens them. In particular, the PANI film synthesized by adding a small amount of nitrogen has the best initial electrical resistance and resistance changing behavior with time after the ex situ iodine (I2)-doping process compared with other auxiliary gases. In addition, it is experimentally demonstrated that the electrical conductivity of the ex situ I2-doped PANI film can be preserved for a long time by isolating it from the atmosphere.

Electrical properties of polyaniline/Cadmium Oxide/ZnO Nanocomposites Thin Films

Polyaniline nanocomposite films were prepared with various weight percentages by in situ polymerization method using aniline, ammonium per sulfate, and cdo as starting materials. The formations of pani and pani/cdo/ZnO composites with regards to the structural and microstructural properties of the materials were investigated by SEM techniques. The DC conductivity of Pure Pani and its composites have been measured in the temperature range from 30°C to 160°C.

Preparing chitosan–polyaniline nanocomposite film and examining its mechanical, electrical, and antimicrobial properties

In recent years, development and progress in modern packaging resulting from degradable natural resources have grown remarkably. In this study, chitosan–polyaniline film was prepared with a combination of different concentrations of polyaniline and various synthesis times to produce antimicrobial and biodegradable packaging film. The physical, electrical, and mechanical properties of the films were investigated. The interaction between chitosan and polyaniline was confirmed by Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction patterns. The size and morphology of the synthesized particles were examined by scanning electron microscopy. The results indicated that the synthesized polyaniline particles had a spherical shape (45–100 nm). The antimicrobial and antifungal activity of the films against Aspergillus niger fungi (antifungal area: 61.47 mm2) and Escherichia coli bacteria (antimicrobial area: 187.27 mm2) increased with increasing the concentration of polyaniline. The results obtained from the study of the effect of polyaniline on the electrical conductivity of the chitosan film showed that increasing the polyaniline concentration and synthesis time resulted in decreased electrical resistance of the film, for which the film with the highest aniline concentration and the highest synthesize time had the lowest resistance. According to the mechanical property results, tensile strength (TS) and elastic modulus were increased due to the addition of the polyaniline to the polymer matrix. The chitosan blank film had a lower TS than nanocomposites. As the final results, the chitosan–polyaniline film has good electrical conductivity, indicating that the produced film could be used in intelligent food packaging.

Fabrication of flexible free-standing reduced graphene oxide/polyaniline nanocomposite film for all-solid-state flexible supercapacitor

Graphene and polyaniline (PANI) are considered as promising electrode active materials. A rational design of composite structure for graphene and PANI is essential and prerequisite for obtaining excellent properties. In this paper, a flexible free-standing reduced graphene oxide (rGO)/PANI nanocomposite film has been successfully prepared through self-assembly and in situ polymerization of anilines in graphene oxide (GO) sheets. Owing to the formation of PANI nanoparticles, the electrochemical capacitance of rGO/PANI nanocomposite film is significantly enhanced. To evaluate electrochemical properties, an all-solid-state flexible supercapacitor is further fabricated through tailoring and assembling the flexible free-standing rGO/PANI nanocomposite film. The nanocomposite film shows high specific capacitance of 0.92 F/cm2 (>1314.3 F/cm3) and its specific capacitance exhibits no obvious fading under bending state or after bending 200 times. The excellent electrochemical performance can be readily ascribed to the synergistic effect between two-dimensional rGO and PANI nanoparticle in the nanocomposite film. This study demonstrates an efficient approach to prepare flexible free-standing active materials for flexible energy storage devices.

Electrochemical detection of Epinephrine using Polyaniline nanocomposite films doped with TiO2 and RuO2 Nanoparticles on Multi-walled Carbon Nanotube

Electrochemical properties of functionalized MWCNT/polyaniline doped with metal oxide (TiO2, RuO2) nanoparticles were explored. Successful synthesis of MWCNT, TiO2, RuO2, PANI, MWCNT-PANI-TiO2, and MWCNT-PANI-RuO2 nano materials were confirmed using suitable characterization techniques. Successful modification of gold (Au) electrode with these nanoparticles was confirmed using electrochemical techniques such as cyclic voltammetry (CV) and electrochemical impedance spectroscopy. Au-MWCNT-PANI-TiO2 and Au-MWCNT-PANI-RuO2 gave the best electron transport properties towards the oxidation of epinephrine (EP) compared with other electrodes investigated. The Tafel values 0.448 and 0.442V/decade for Au-MWCNT-PANI-TiO2 and Au-MWCNT-PANI-RuO2 electrodes respectively in (EP) suggest adsorption due to analyte oxidation intermediates products. The linear calibration plot was obtained for EP at concentrations range 4.9 to 76.9μM. The limits of detection of EP were estimated to be 0.16 and 0.18μM for Au-MWCNT-PANI-TiO2 and Au-MWCNT-PANI-RuO2 electrodes respectively. The interference study using DPV showed clear peak separation for amino acid (AA) and EP. Therefore, the modified electrodes can selectively detect epinephrine without interference from ascorbic acid signal. The analytical performance of the fabricated sensors has been evaluated for detection of epinephrine (EP) in a pharmaceutical sample with satisfactory results.

Preparation, Characterization, and Electrochromic Properties of Nanocellulose-Based Polyaniline Nanocomposite Films

On the basis of nanocellulose obtained by acidic swelling and ultrasonication, rodlike nanocellulose/polyaniline nanocomposites with a core-shell structure have been prepared via in situ polymerization. Compared to pure polyaniline, the nanocomposites show superior film-forming properties, and the prepared nanocomposite films demonstrate excellent electrochemical and electrochromic properties in electrolyte solution. Nanocomposite films, especially the one prepared with 40% polyaniline coated nanocomposite, exhibited faster response time (1.5 s for bleaching and 1.0 s for coloring), higher optical contrast (62.9%), higher coloration efficiency (206.2 cm2/C), and more remarkable switching stability (over 500 cycles). These novel nanocellulose-based nanorod network films are promising novel electrochromic materials with excellent properties.

Novel Method to Synthesize Conducting Polyaniline/nickle Sulphide Nanocomposite Films and the Study of their Structural and Electrical Properties

Different methodologies and routes have been adopted to enhance compatibility and applications of conjugated polymers since two decades. In this project we have adopted a novel method to synthesize polyaniline nanocomposite films with different weight percentages of nickel sulphide nanoparticles. These nanocomposite films were than subjected to various characterizations such as X-ray diffraction analysis, scanning electron microscopy (SEM), and standard four probe method to study the effect of various weight percentages of nanoparticles on structural and electrical properties.

Electrochromic and electrochemical capacitive properties of tungsten oxide and its polyaniline nanocomposite films obtained by chemical bath deposition method

Polyanine and its nanocomposite WO3/PANI films were deposited on fluorine doped tin oxide (FTO) glass slides by simple chemical bath deposition method. The morphology structure of the composite film was studied using atomic force microscopy (AFM) and scanning electron microscopy (SEM), while the electrochemical capacitive properties were determined using cyclic voltammetry (CV), chronopotentiometry (CP) and electrochemical impedance spectroscopy (EIS). The WO3/PANI nano-composite exhibited multiple colors (electrochromism) during the CV scans, from brownish green to transparent to light green then back to brownish green. Surprisingly, the integration of the PANI with the WO3 led to synergistic performance of nanohybrid wherein a true electrochemical double layer capacitor was obtained. Also, interestingly and unlike literature reports, the CBD method led to excellent capacitance retention (>98%) of the PANI even at 1000 continuous cycles. This work demonstrates that simple CBD can be used to get WO3/PANI films that give good electrochromism and pseudo-capacitance comparable to the ones obtained by other methods. Hence the obtained nanocomposite film of WO3/PANI can be a promising material for electrochromic and energy storage applications.

Synthesis and simultaneous enhancements in electrical and magnetic properties of oriented γ-Fe2O3-nanoneedle/PANI nanocomposite films by cold stretching

The polyaniline (PANI) nanocomposite films with an oriented alignment of γ-Fe2O3-nanoneedles were prepared for the first time via a facile solution evaporation method under an applied magnetic field. The γ-Fe2O3 nanoneedles were coated with PANI in advance to get the uniform dispersion of γ-Fe2O3 nanoneedles in the PANI matrix. The nanocomposite films were then stretched at very low strains at room temperature before doping. It was interesting to notice that the cold stretching could largely enhance both the electrical and magnetic properties of the nanocomposite films. Particularly, the maximum electrical and magnetic properties in both the directions parallel and perpendicular to the stretching direction were obtained at the elastic limit stress level for the stretched nanocomposite films. The enhancements in the electrical and magnetic properties were properly interpreted based on the variances in the morphology, structure and crystallinity degree of PANI matrix.

An amperometric oxalate biosensor based on sorghum oxalate oxidase bound carboxylated multiwalled carbon nanotubes–polyaniline composite film

A highly sensitive, specific and rapid electrochemical oxalate biosensor was constructed by covalently immobilizing sorghum leaf oxalate oxidase on carboxylated multiwalled carbon nanotubes and conducting polymer, polyaniline nanocomposite film electrodeposited over the surface of platinum (Pt) wire using N-ethyl-N′-(3-dimethylaminopropyl) carbodiimide (EDC) and N-hydroxy succinimide (NHS) chemistry. The modified electrode was characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectrophotometry. The optimized oxalate biosensor showed linear response range of 8.4–272 μM with correlation coefficient of 0.93 and rapid response within 5 s at a potential of 0.4 V vs Ag/AgCl. The sensitivity was approximately 0.0113 μA/μM with a detection limit of 3.0 μM. Proposed oxalate biosensor was successfully applied to human urine sample.

Characterization and conductivity studies of nanocomposite films with polymer networks containing polyaniline-alginate/titanium dioxide

Polyaniline nanocomposite films were chemically synthesized in the presence of alginate template by varying the concentration of TiO2 in the composites. Characterization of the composite samples by FTIR, UV-Vis spectra (UV), and X-ray diffraction (XRD) indicates the formation of polyaniline-alginate/titanium dioxide (PAT) composites. The morphology analysis by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) also supports the formation of the composites. Temperature-dependent DC conductivity of the polyaniline-alginate (PA) and PAT composites was studied in the range of 300 ≤ T ≤ 500 K. UV-Vis and FTIR spectral studies reveal that the alginate is a good template for the chemical interaction between polyaniline and TiO2, which suggests that the micelles formed by the anilinium-alginate cations containing TiO2 are responsible for the transport properties of the PAT composites. POLYM. COMPOS., 31:1754–1761, 2010. © 2010 Society of Plastics Engineers.