Yilkal D. Sintayehu; H. C. Ananda Murthy
Abstract
The involvement and development of intelligent polymers in enzymes as a catalyst have been interesting to develop processes that are environmentally benign, energy efficient, and selective towards their specific molecular applications. Polypyrrole based enzyme nanocomposites represents a continuous considerable ...
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The involvement and development of intelligent polymers in enzymes as a catalyst have been interesting to develop processes that are environmentally benign, energy efficient, and selective towards their specific molecular applications. Polypyrrole based enzyme nanocomposites represents a continuous considerable redox organic polymer that have been increased in electromechanical devices in advance for surface functionalization. This review addresses the fundamental concepts of polypyrole and its composites role for enzyme immobilizing functioning and its bio functional bioelectrocatalytic system operating principle in biosensor and biofuel cells as well as its involvement in electron transfer mechanism as a bio electrode to create an advanced bioelectronics device from power generating system to extreme analyte detecting system. Copyright © VBRI Press.

Bhavna H. Meshram; Subhash B. Kondawar
Abstract
Fabrication of nanocomposite film of electrically conducting polypyrrole (PPy) and functionalized multi-walled carbon nanotubes (MWCNTs) on a stainless steel electrode by electro-deposition method and immobilization of urease onto the nanocomposite film to obtain a nanobiocomposite electrode as a sensitive ...
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Fabrication of nanocomposite film of electrically conducting polypyrrole (PPy) and functionalized multi-walled carbon nanotubes (MWCNTs) on a stainless steel electrode by electro-deposition method and immobilization of urease onto the nanocomposite film to obtain a nanobiocomposite electrode as a sensitive electrochemical urease biosensor is reported. Cross-linking by glutaraldehyde (0.1%) method for the immobilization of urease (2 mg/mL) in a phosphate buffer solution of 0.1 molarity at a pH of 7.0 was used. The Characterization of the nanocomposite and nanobiocomposite film thus obtained was done by Scanning Electron Microscopy (SEM), Fourier Transform Infrared spectroscopy (FTIR), Cyclic Voltammetry (CV), and Electrochemical Impedance Spectroscopy (EIS). The increased size of the Cyclic voltammogram and shifting of anionic peaks towards the lower voltage indicates the incorporation of MWCNTs into the growing film during the electro-deposition of PPy on electrode. Reduction of the oxidation potential due to MWCNTs leads to lowering of potential for the electro-catalytic reduction of urea. The incorporation of functionalized MWCNT also made possible increased amount of enzyme concentration, an extended lifetime, long time stability and improved response times of the enzyme electrode. This modified nanobiocomposite electrode showed a good linear response to the urea concentration change in the range of 10 mM to 50 mM. The results obtained from Michaelis–Menten constant K´m, maximum current (Imax), detection limit, sensitivity, response time and shelf-life of electrochemical biosensor indicating good sensing for urea detection.

Ritu P. Mahore; Devendra K. Burghate; Subhash B. Kondawar; Ashish P.Mahajan; Deoram V. Nandanwar
Abstract
Due to the ever growing demand of energy for various applications attention of researchers is aroused by Supercapacitors due to its superior power, energy density and cyclic life. Electrode material mainly determines the performance of Supercapacitors. Conducting polymers, metal oxides and carbon based ...
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Due to the ever growing demand of energy for various applications attention of researchers is aroused by Supercapacitors due to its superior power, energy density and cyclic life. Electrode material mainly determines the performance of Supercapacitors. Conducting polymers, metal oxides and carbon based materials are mainly used as electrode materials in Supercapacitors. Among these three categories of materials, Conducting polymers and metal oxides shows pseudo-capacitance. This paper reported the synthesis of Pure Polypyrrole (PPy) and Polypyrrole/Manganese dioxide (PPy/MnO2) nanocomposites by in-situ chemical oxidative polymerization. The synthesized materials were tested as potential candidates for the electrodes of supercapacitor. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) revealed that nanoparticles of MnO2 are well incorporated into PPy matrix. Cyclic Voltammetry (CV) indicated that PPy/MnO2 nanocomposites have an ideal capacitive behaviour and an excellent cyclibility. Electrochemical impedance spectroscopy (EIS) and Galvanostatic charge-discharge (GCD) measurements proved that nanocomposite electrode with 10% MnO2 composition showed the smallest charge transfer resistance and highest specific capacitance compared to other compositions. The electrochemical studies of PPy/MnO2 nanocomposites showed that PPy/MnO2 nanocomposites are suitable advanced materials for electrodes of the supercapacitors. Copyright © 2018 VBRI Press.

Gazala Ruhi; Haritma Chopra;Sundeep K. Dhawan; Pradeep Sambyal; Hema Bhandari
Abstract
In a novel approach, Polypyrrole/Gum Acacia composites (PPy/GA) were synthesized by in-situ oxidative polymerization of pyrrole on the Gum Acacia (GA) surface by using FeCl3 as oxidant. The 1 HNMR and FTIR confirms the presence of peaks of Polyprrole and Gum Acacia in the composite. The microstructural ...
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In a novel approach, Polypyrrole/Gum Acacia composites (PPy/GA) were synthesized by in-situ oxidative polymerization of pyrrole on the Gum Acacia (GA) surface by using FeCl3 as oxidant. The 1 HNMR and FTIR confirms the presence of peaks of Polyprrole and Gum Acacia in the composite. The microstructural analysis of the composite reveals uniform layer of Polypyrrole on the surface of GA particles. The X-ray Diffraction pattern reveals the amorphous nature of the composite. Powder coating technique was used to design the composite coatings. The electrochemical studies like Open Circuit Potential (OCP) variation with time, Potentiodynamic Polarization and Electrochemical Impedance Spectroscopy (EIS) were conducted in 3.5% NaCl solution to evaluate the corrosion resistance of the coatings. The composite coatings demonstrated superior corrosion resistance in salt spray fog of 5.0% NaCl (under accelerated test conditions in salt spray chamber). The synergistic combination of the corrosion inhibition properties of Gum Acacia and the redox properties of Polypyrrole is the reason for the occurrence of high corrosion resistance of the composite coatings. The present coating composition has shown excellent corrosion resistance and can be a potential coating formulation for mild steel substrate used in various applications under saline conditions.

Jyoti Srivastava; Pawan Kumar Khanna; Priyesh V More; Neha Singh
Abstract
Silver/Polypyrrole/Polyvinylalcohol polymer nanocomposite films were prepared by in-situ polymerization of pyrrole with variable loading of silver nanoparticles from 0.5-10%. The conducting films prepared from the nanocomposite solution were flexible, light weight, thermally stable and showed high ...
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Silver/Polypyrrole/Polyvinylalcohol polymer nanocomposite films were prepared by in-situ polymerization of pyrrole with variable loading of silver nanoparticles from 0.5-10%. The conducting films prepared from the nanocomposite solution were flexible, light weight, thermally stable and showed high hydrophobicity/hydrophilicity ratio. X-Ray diffraction measurement showed formation of fcc silver nanoparticles with particle size in the range of about 20-40 nm. UV-visible spectroscopy revealed the characteristic bands of Ag nanoparticles and polypyrrole in the so obtained co-polymer nanocomposites. The SEM studies of the nanocomposite films showed that the filler material was well conjugated in the Polymer matrix. Vector Network Analyser showed Electromagnetic shielding efficiency (EMI) efficiency as high as -35 dB in the X band (8-12GHz).
Ritu P. Mahore; Devendra K. Burghate; Subhash B. Kondawar
Abstract
Supercapacitors are recognized as one of the most promising energy storage devices for a wide range of civilian and military applications in electric vehicles, uninterruptible power supplies. Conducting polymer nanocomposites are new functional materials suitable for supercapacitors due to synergistic ...
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Supercapacitors are recognized as one of the most promising energy storage devices for a wide range of civilian and military applications in electric vehicles, uninterruptible power supplies. Conducting polymer nanocomposites are new functional materials suitable for supercapacitors due to synergistic effect of individual components. In present work, polypyrrole/CNT nanocomposites have been prepared by an in-situ chemical polymerization method and studied for supercapacitor. CNTs were well functionalized using 3:1 ratio of H2SO4 and HNO3 before polymerizing the pyrrole. Analytical techniques such as SEM, UV-VIS and FTIR were used to characterize the synthesized materials. The SEM images reveal that the materials have rough and granular morphology. The composites showed good interaction based on the shift to longer wavelengths in the electronic transition, indicating the interaction between PPy and functionalized CNTs as observed in their UV-VIS and FTIR spectra. The electrochemical performance was evaluated by using cyclic voltammetry (CV) in 1M Na2SO4 electrolyte and specific capacitance was obtained at 0.5 V/s for pure polypyrrole and PPy/CNT nanocomposites. Nanocomposite showed the enhanced electrochemical performance as compared to that of pure polypyrrole. The specific capacitance obtained at the scan rate 0.5V/s was found to be 0.825 F/cm -2 for pure polypyrrole and 1.0619 F/cm -2 for PPy/CNT nanocomposite material respectively, indicates that PPy/CNT nanocomposite is suitable material as electrode for supercapacitor as compoared to pure polypyrrole.