Polyaniline Graphene Nanocomposite Research Articles

Electronic Properties of Polyaniline-Graphene Nanocomposites Synthesized via Solution Mixing Method.

A key advantage of combining the exceptional properties of graphene with conducting polymers, lies in their remarkable property tunability through filler additions into polymer matrices, with synthesis routes playing a crucial role in shaping their characteristics. In this work, we examine the electronic properties of polyaniline(PANI) and graphene nanocomposites synthesized via a simple solution mixing method, which offers advantages such as ease of use and efficiency. Increasing graphene content enhances nanocomposite conductivity, and a percolation effect is observed. The percolation threshold is high and is consistent with a strong role played by voids in the structure. Temperature-dependent conductivity measurements highlight three distinct conduction regimes: insulating, critical, and metallic. These findings underscore the significant influence of synthesis method and structural disorder on shaping electronic properties, paving the way for engineering multifunctional nanocomposites with exceptional versatility and performance.

The preparation of polyaniline/graphene/polypropylene nanocomposite and its novel antibacterial activity

AbstractThe demand for polymers with antibacterial properties is increasing in food packaging industry and medical supplies. Antibacterial additives without toxic metal ion release are crucial for health and safety but still have challenges. Herein, polypropylene (PP) nanocomposite was prepared with polyaniline/graphene nanocomposite (PANI/GNP) as a green antibacterial additive due to its electrostatic, free radical, and nanoknife effect synergistic antibacterial mechanisms. To improve the dispersibility of PANI/GNP, nanosilica coating on PANI/GNP was constructed successfully with in situ condensation polymerization of epoxy functionalized ethyl orthosilicate to obtain EP‐nSiO2‐PANI/GNP. EP‐nSiO2‐PANI/GNP with a thin nanosilica coating has a significantly improved thermal stability as compared with that of PANI/GNP characterized by TGA. The EP‐nSiO2‐PANI/GNP presents a nanoscale disperse state in PP nanocomposite and thus enhances the melt viscosity and storage modulus accordingly characterized by TEM and Rheology. The EP‐nSiO2‐PANI/GNP/PP filled with 0.5 wt% of EP‐nSiO2‐PANI/GNP demonstrates antibacterial activity of 100% against both Escherichia coli and Staphylococcus aureus.Highlights In situ condensation polymerization to prepare EP‐nSiO2‐PANI/GNP. EP‐nSiO2‐PANI/GNP has enhanced dispersion stability. EP‐nSiO2‐PANI/GNP with a thin nanosilica coating has a good thermal stability. PP nanocomposite with 0.5 wt% filler has excellent antibacterial activity. The electrostatic, free radical, and nanoknife effect antibacterial mechanism.

Wideband Radar Absorbing Structure Using Polyaniline-Graphene Nanocomposite

A wideband non-resonant absorber is proposed, and its radar cross section (RCS) reduction is investigated. A discussion on the functional materials available is followed by the design of an absorber on a Plexiglas substrate with polyaniline-graphene nanocomposite as layered square inclusions with thicknesses and conductivities scaled to golden ratio. The measured dielectric properties of polyaniline-graphene nanocomposites are used in the fullwave simulation. The design parameters have been identified and optimized using CST Microwave Studio. As designed structure is fabricated and the reflection is measured. The objective of the work is to demonstrate the use of non-metallic conducting polymer composites devoid of metals for radar absorbing material (RAM) structural designs. The structure is an all-polymer and electrically thin design with a potential to be 3D printed to suit the target object.

Simultaneous electro-synthesis of polyaniline graphene nanocomposite in dilute graphene oxide as dopant and aniline by electrochemical method and its high specific capacitance

A composite of reduced Graphene oxide -polyaniline (RGO-PANI) was fabricated by an in situ electrochemical oxidative polymerization of aniline in the presence of GO in Sodium dodecyl sulfate (SDS), which synthsized by anodic exfoliation, on carbon paper electrode. Here GO uses as a protonation agent for doping of PANI and also as a physical crosslinker of PANI fibers. The structure and the property of RGO-PANI composite were investigated by tunneling electron microscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, cyclic voltammetry, galvanostatic charge–discharge test and electrochemical impedance spectroscopy (EIS) techniques. The fabricated composite was then employed as the supercapacitor, which provides specific capacitances as high as 890 F g−1 at the current density of 1 A g−1 in 1 M H2SO4 aqueous solution. Long term stability and high specific capacitance, are related to synergistic effects between PANI and RGO and also conductive graphene sheets. EIS indicates a decreasing charge transfer resistance at the electrode/electrolyte interface of RGO-PANI composite than each individual component. This work may suggest an alternative method to synthesis one-pot produce of RGO-PANI composite for the development of high-performance supercapacitors.

Electrochemical deposition and characterization of polyaniline-graphene nanocomposite films and its corrosion protection properties

Polyaniline and polyaniline-graphene nanocomposite films were electrochemically deposited by cyclic voltammetry on 310 stainless steel electrode. The corrosion resistance of polyaniline and polyaniline-graphene nanocomposite covered 310 stainless steel substrates was estimated using potentiodynamic polarization and electrochemical impedance spectroscopy techniques in 5000 ppm NaCl aqueous solution at room temperature. Potentiodynamic polarization results show, which corrosion potentials shift to anodic regions in the presence of polyaniline-graphene nanocomposite compared to the pure aniline film. The electrochemical measurements also indicated that the inhibition efficiency for polyaniline-graphene nanocomposite and polyaniline are about 97 % and 73 %, respectively.

Polyaniline/Graphene nanocomposite coatings on copper: Electropolymerization, characterization, and evaluation of corrosion protection performance

Polyaniline–graphene nanocomposite film was electrochemically deposited by cyclic voltammetry on copper electrode. The corrosion resistance of polyaniline–graphene nanocomposite covered copper substrates was estimated using potentiodynamic polarization and electrochemical impedance spectroscopy techniques in 5000ppm NaCl aqueous solution at room temperature. Potentiodynamic Polarization results show that corrosion potentials shift to anodic regions in the presence of polyaniline–graphene nanocomposite compared to the blank solution. The electrochemical measurements, also, indicated that the inhibition efficiency for polyaniline-graphene nanocomposite is 98%.

Synthesis and Microwave Absorption Properties of Polyaniline-Graphene Nanocomposites

To develop novel microwave absorbing materials, polyaniline (PANI) composites filled with graphene was prepared, and the morphology, crystallographic structures and microwave parameters of the composites were investigated by SEM, XRD, FTIR and HP8722ES network analyzer. The uniform dispersion of graphene significantly enhanced the formation of conductive pathways in the PANI arrays and the interfacial affinity between PANI and graphene increases the number of conductive pathways of electron transfer. The composites show great microwave absorbing properties of −17dB. This study reveals that the PANI-Graphene composite is promising for applications as microwave absorbing material.

Controllable Preparation of Polyaniline-Graphene Nanocomposites using Functionalized Graphene for Supercapacitor Electrodes.

In order to explore the effect of graphene surface chemistry on electrochemical performance based on polyaniline-graphene hybrid material electrodes, four different polyaniline-graphene nanocomposites were fabricated with graphene oxide, reduced graphene oxide, aminated graphene and sulfonated graphene as carriers, respectively. The nanocomposites feature various structures and morphologies, which could be used to more deeply understand the morphology and structure effects caused by surface chemistry on electrochemical performance. The experimental results reveal that functionalized electronegative graphene was conducive to the vertical and neat growth of polyaniline (PANI) nanorods. The array architecture endowed the PANI-GS nanocomposite with a large ion-accessible surface area and high-efficiency electron- and ion-transport pathways. Meanwhile, the introduction of sulfonic acid functional groups accelerated the redox reaction with doping and dedoping of the PANI. Thereby, the PANI-GS nanocomposite exhibited a high specific capacitance of 863.2 F g(-1) at a current density of 0.2 A g(-1) and the excellent rate capability of 67.4 % (581.6 F g(-1) at 5 A g(-1) ), which were much better than the other three nanocomposites produced.

Electrochemical detection of nitrite based on glassy carbon electrode modified with gold–polyaniline–graphene nanocomposites

This study reports possible interferences for the detection of NO2− on a Au–G–PANI/GCE.

High-performance supercapacitors based on silver nanoparticle–polyaniline–graphene nanocomposites coated on flexible carbon fiber paper

For practical use of supercapacitors, new electrode materials are needed with high ionic adsorption capacity at the solid–liquid interface, fast and reversible surface redox reaction, and fast charge transfer. In the current study, we produce a new hybrid material of electrochemical double layer capacitive graphene, pseudocapacitive polyaniline (PANI) and highly conductive silver nanoparticles (AgNPs). The nanocomposite of AgNP–PANI–graphene in a weight ratio of 0.1 : 1 : 1, coated on flexible carbon fiber paper (CFP), exhibits high specific capacitance and capacity retention. At an applied current density of 1.5 A g−1, the maximum specific capacitance of AgNP–PANI–graphene/CFP is 828 F g−1, which is about 4.0-, 2.2-, 1.6-, and 1.5-fold higher than those of graphene/CFP, PANI/CFP, AgNP–PANI/CFP, and PANI–graphene/CFP, respectively. The capacity retention of AgNP–PANI–graphene/CFP after a charge–discharge test having 3000 cycles is 97.5% of the original specific capacitance. This was 4.4, 12.9, 14.5, and 23.5% more stable than PANI–graphene/CFP, graphene/CFP, AgNP–PANI/CFP, and PANI/CFP, respectively. An 0.8′′ × 6′′ all-solid-state supercapacitor device composed of AgNP–PANI–graphene/CFP exhibited a specific capacitance of 142 F g−1 measured at an applied current density of 1.5 A g−1 and a wide working potential of 6.2 V after consecutive charge–discharge tests over a 16.40 h period. This fully charged supercapacitor could power a 3 V motor for 7.30 min.

Nanostructured polyaniline decorated graphene sheets for reversible CO2 capture

The current scientific community is extensively involved in developing novel materials for energy and environmental applications. Capture of CO2 to remove it from the atmosphere is one of the most important applications among them. In the present work, we have demonstrated for the first time, to the best of our knowledge, a polyaniline–graphene nanocomposite as a CO2 capture candidate. Graphene was prepared by hydrogen induced thermal exfoliation of graphite oxide and was further coated with polyaniline using a chemical method. The nanocomposite was characterized by different techniques and the capture capacity was measured using a high pressure Sievert’s apparatus. FTIR spectroscopy was used to confirm the possible CO2 capture mechanism in the nanocomposite. CO2 adsorption capacities at a pressure of 11 bar and different temperatures of 25, 50 and 100 °C were experimentally found to be 75, 47 and 31 mmol g−1, respectively. This nanocomposite shows much higher CO2 capture capacity compared to pure graphene and shows a high degree of recyclability.