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For modern high‐tech flexible energy storage devices, it becomes important to synthesize micro‐/nanostructures as per the required shape and morphology with superior physical and electro‐active characteristics. This work shares the fabrication and characterization of ZnSn(OH)6 (Zinc hydroxystannate [ZHS]) prepared by facile microwave‐assisted technique and furthermore converted into flexible sheets by employing lignocelluloses (LC) known as natural fibers, collected from Carica papaya leaf petiole as a substrate to provide the flexible matrix. X‐ray diffraction measurements confirm the successful crystalline structure of ZHS. Scanning electron microscopy and transmission electron microscopy showed the solid spherical structure of ZHS microspheres. Fourier transform infrared spectrometry and Raman spectroscopy confirmed the composite formation of ZHS and LC‐based composite sheets (ZHS/LC sheets). Electrochemical measurements that is, cyclic voltammetry (CV), Galvanostatic charge/discharge, and electrochemical impedance (EIS) spectroscopy revealed the electroactive behavior of ZHS/LC paper sheets as working electrode for energy storage applications. CV measurements revealed the specific capacitance of 100 F/g and EIS measurements confirmed the decrease in the resistance of LC fiber after the growth of ZHS microspheres. Presented flexible ZHS based paper sheets will be highly feasible for the modern bendable/flexible/disposable energy storage applications. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) nanostructures were synthesized via a one‐step solid‐state reaction approach in ammonia (NH3) gas environment with different temperature ramp rates. The so‐formed nanostructures were characterized using X‐ray diffraction (XRD) for phase identification, where the typical wurtzite hexagonal structure was observed. Scanning electron microscopy (SEM) confirmed the particle size to be in the range 45–50 nm, the same as calculated by the XRD pattern for the ramp rate of 10 °C/min. Energy dispersive X‐ray (EDX) spectroscopy and X‐ray photoelectron spectroscopy (XPS) confirmed the chemical purity of the samples. The photoluminescence (PL) spectrum indicated multiple near‐band‐edge emissions and energy‐band emissions. Then, these ZnO nanomaterials were used for the degradation of crystal violet (CV) dye under UV light irradiation. The CV solution was completely degraded in 2 hr. The initial photocatalyst and dye amounts of 0.2 g/100 ml and 0.5 mg/L, respectively, were found to be the optimum values for maximum degradation efficiency. The ZnO‐based photocatalyst was stable up to three cycles of reuse. These results indicate that the high surface area and porosity of the nanomaterials are responsible for the high efficiency, which was confirmed by specific surface area analysis. [ABSTRACT FROM AUTHOR]

Abstract: Surface morphology induced electrical conductivity and specific surface area of a material play a significant role to facilitate electrochemical behavior for supercapacitor application. Therefore, the synthesis step for controlling such parameters becomes very imperative and challenging. Herein, a ZnS nanoweb is deposited directly onto Ni foam with a pre‐deposited thin layer of hydrothermally prepared graphene oxide. The structure and surface morphology of the deposited ZnS is observed using XRD and SEM, respectively. The electrical conductivity of the graphene oxide supported ZnS nanoweb, determined using the four probes method, is 100.15 S cm−1. The specific surface area is 104.42 m2 g−1 as determined by BET measurements. Pseudocapacitive behavior is monitored by cyclic voltammetry, and the excellent specific capacity of 3052 Fg−1 has been found at a scan rate of 2 mV s−1, while it is 2400.30 Fg−1 according the galvanostatic charge‐discharge profile at a current density of 3 mA cm−2. Both values are significantly higher than those measured for bare GO or ZnS layers. The energy and power densities of GO supported ZnS nanoweb are determined in a three electrode setup, are 120 Wh Kg−1 at 3 mA cm−2 and 4407.73 Wkg−1, respectively. In a symmetric two electrode setup, an energy density of 20.29 Wh Kg−1 at 2 mA cm−2 is observed. Hence, both symmetric and asymmetric measurements suggest that GO supported ZnS nanoweb can be applied as a suitable electrode for supercapacitors. [ABSTRACT FROM AUTHOR]

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]

ABSTRACT Direct use of lignocelluloses fibers as substrate for fabrication of conductive, electroactive, biodegradable, and low-cost electrode materials are in demand for high-tech applications of ion-exchange and energy storage devices. This article presents the preparation and characterizations of conductive and electroactive lignocelluloses-polyaniline (cellulose/PANI) composite paper. Lignocelluloses fibers were directly collected from the stem of self-growing plant, Typha Angusitfolia, and subsequently coated with the conductive and electroactive layer of PANI through chemical synthesis. Individual PANI-coated lignocelluloses fibers were converted into sheet and further characterized with Scanning Electron Microscopy, Fourier Transform Infrared, Thermogravimetric Analysis, electronic conductivity, and Cyclic Voltammetry. Cellulose/PANI composite paper revealed superior thermal characteristics and used as a working electrode in three different electrolytes for ion-exchange properties. Conductive composite paper (CCP) showed the charge storage capacity of ∼52 C/g at scan rate of 5 mV/s in 2 M HCl solution. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42293. [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]

ABSTRACT Reduced size dual band patch antenna is designed on pulp fibers-based substrate, obtained from a self-growing plant, Typha angustifolia. The proposed design is low cost and has <10 dB return loss at 2.4 and 5.7 GHz, with 6.9 dBi antenna gain and also has potential for conformal designs. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2146-2148, 2016 [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]