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ABSTRACT Development of thin, flexible, light-weight, renewable, low-cost, and environmentally friendly electrode materials are highly feasible in era of modern disposable electronic technology. This article presents the synthesis and dielectric studies of polypyrrole (PPy) coated pulp fibers, directly collected from wasted egg holder's tray. PPy coated pulp fibers converted into compact sheet for the development of potential renewable and low-cost electrode materials. The morphology, chemical structure, and thermal stability of naked and PPy coated pulp fibril sheets were investigated by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) and thermogravimetric analysis (TGA), respectively. PPy coated pulp fibers revealed better thermal stability and compactness of sheet morphology. Impedance measurements showed a high value of dielectric constant of 1.15 × 106 at 0.5 Hz and conductivity of 7.45 × 10−4 S/cm at room temperature for PPy coated pulp fibril sheet. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42422. [ABSTRACT FROM AUTHOR]

Composites of polypyrrole (PPy) and Cladophora nanocellulose, reinforced with 8 μm-thick chopped carbon filaments, can be used as electrode materials to obtain paper-based energy-storage devices with unprecedented performance at high charge and discharge rates. Charge capacities of more than 200 C g−1 (PPy) are obtained for paper-based electrodes at potential scan rates as high as 500 mV s−1, whereas cell capacitances of ∼60-70 F g−1 (PPy) are reached for symmetric supercapacitor cells with capacitances up to 3.0 F (i.e.,0.48 F cm−2) when charged to 0.6 V using current densities as high as 31 A g−1 based on the PPy weight (i.e., 99 mA cm−2). Energy and power densities of 1.75 Wh kg−1 and 2.7 kW kg−1, respectively, are obtained when normalized with respect to twice the PPy weight of the smaller electrode. No loss in cell capacitance is seen during charging/discharging at 7.7 A g−1 (PPy) over 1500 cycles. It is proposed that the nonelectroactive carbon filaments decrease the contact resistances and the resistance of the reduced PPy composite. The present straightforward approach represents significant progress in the development of low-cost and environmentally friendly paper-based energy-storage devices for high-power applications. [ABSTRACT FROM AUTHOR]

Flexible, lightweight, and environment friendly energy storage devices are in high demand of modern disposable technology. This study presents the coating of directly collected lignocelluloses fibers from self‐growing plant, Monochoria vaginalis with conducting layers of polypyrrole and polyaniline. Fabricated paper electrodes were conductive, electroactive, all‐organic constituents, flexible, and can be cut with help of scissor in any shape. Paper electrodes were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis for morphology, structural, and thermal characteristics, respectively. Furthermore, fabricated paper electrodes were characterized by cyclic voltammetry to confirm the electroactive behavior and showed excellent electrochemical performance. Paper sheets comprising lignocelluloses fibers and polypyrrole coating (LC/PPy) were employed as electrodes of symmetric cell and showed specific capacitance of 230.35 Fg−1 at current density 0.25 mA g−1 for LC/PANI, while LC/PPy showed 9.042 W h kg−1 and 91.33 W kg−1 energy density and power density, respectively. This paper electrodes are highly feasible for environmentally safe and flexible energy storage applications, particularly in era of modern disposable technology. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47282. [ABSTRACT FROM AUTHOR]

Abstract: The electrochemical properties of a novel composite paper material of high surface area consisting of polypyrrole (PPy) deposited on cellulose derived from Cladophora sp. algae have been investigated in electrolytes containing different concentrations of nitrate, chloride and p-toluene sulfonate, as well as in solutions containing both p-toluene sulfonate and chloride. The oxidation mechanism and the dependence of the oxidation behavior of the polypyrrole, which was obtained by oxidation of pyrrole with iron(III) chloride, on the anion type and concentration have been studied. Current nucleation maxima, appearing at different times depending on the anion concentration, were obtained during the oxidation of the reduced polymers as a result of the combined action of the formation and growth of conducting polymer strands and anion diffusion. No loss of capacity was seen during repeated oxidation and reduction of the polymer indicating that trapping of anions in the reduced polymer did not limit the electroactivity of the present material. The latter can be explained by the thin polymer layer present on the cellulose substrate. During the oxidation of the polymer, the anions most likely first cover most of the surface of the composite before diffusing into the bulk of the polymer. The estimated distance between these surface sites was also found to match the size of the anions. For electrolytes containing a mixture of anions, the oxidation charge depends on the concentration and size of the different anions. The combination of the thin polymer coating and the large specific surface area of the composite give rise to a high ion absorption capacity even for large anions. Hence, the investigated material should be well-suited for use in biotechnological applications involving, e.g., desalting and extraction of proteins and DNA from biological samples. [Copyright &y& Elsevier]