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In the present work, the synthesis of novel nanocomposite adsorbent based on graft copolymer of Poly(AA)/GG incorporated silver nanoparticles (AgNPs) has been carried out for the elimination of Methylene blue (MB) dye from the aqueous phase. The characterization of synthesized nanocomposite has been carried out by using various analytical techniques such as UV–Vis, FTIR, XRD, FE-SEM, EDX, DLS and BET studies. The UV–Vis, DLS and XRD studies revealed the stable formation of AgNPs inside the polymer matrix with an average size of 100 ± 1 nm. The − 26.40 mV value of Zeta potential also confirms the stability of AgNPs inside the polymer matrix. Furthermore, the resultant adsorbent with an improved adsorption capacity is used to eliminate the MB dye from liquid phase. The parameters such as adsorbent dose and pH of dye solution in adsorption process are optimized. Moreover, the study of the adsorption kinetics and isotherm indicate that the pseudo-second-order kinetics and Langmuir isotherm model is more suitable for describing the experimental adsorption data having maximum adsorption capacity of 833.33 mg/g. Further, the positive values of enthalpy and entropy change specify that the adsorption of MB dye onto the surface of AgNPs/GG/Poly(AA) is endothermic, spontaneous and favorable process. Hence, In-situ synthesis of AgNPs inside polymer and grafting of AA as monomer onto GG has proven to be accountable for the substantial changes in adsorption capacity for removal of MB dye from aqueous phase. Therefore, the resultant AgNPs/GG/Poly(AA) nanocomposite may prove to be a noble adsorbent for the removal of MB dye from the liquid phase.

Polyaniline (PANI) film synthesized by cyclic voltammetry method. Rectangular strip of stainless steel (SS) is used to construct low cost electrode for Supercapacitors. PANI films are characterized by Field-emission scanning electron microscopy (FE-SEM), X-ray diffraction analysis (XRD). Chemical structure and electronic behavior of PANI film is carried out by Fourier transform infrared (FTIR), and ultraviolet-visible (UV-Vis) spectroscopy, respectively. The electrochemical performance of PANI film carried out by cyclic voltammetry in 1M H2SO4 giving specific capacitance of 346 Fg-1 at sweep rate 10 mVs-1 with 63% capacitance retention after 1000 cycles at sweep rate 100 mVs-1.

A novel ecofriendly microwave-assisted xanthan gum-cl-poly (acrylic acid)/AgNPs (MW-XG-cl-pAA/AgNPs) hydrogel nanocomposite has been synthesized by using free radical graft polymerization method. Xanthan gum (XG) acts as stabilizer to produce stable uniform AgNPs in the presence of stem extract of Nepeta leucophylla inside the polymer network. The evidence of incorporation of AgNPs inside the polymer matrix, grafting of acrylic acid (AA) onto backbone XG, surface morphology, crystallinity, thermal properties and effective loading of KCl inside the synthesized hydrogel nanocomposite are attained by using various analytical techniques, such as ultraviolet–visible, Fourier transform infrared, field emission scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction and thermogravimetric analysis. The influence of incorporation of silver nanoparticles inside polymer matrix is also examined. Moreover, in order to explore the swelling and releasing kinetic behavior of synthesized nanocomposite mathematical modeling (Fick’s law) has been used here. Here, the resulting nanocomposite is used for the application of water retention potential of different soil samples and controlled release of KCl. It is evident from the studies that the synthesized nanocomposite acts as water reservoir in different types of soil and maintains the moisture for more than 60 days. Further, the high value of initial diffusion coefficient ( $$ 5.458 \times 10^{ - 6}\,{\text{m}}^{2} /{\text{h}} $$ ) as compared to late diffusion coefficient ( $$ 1.453 \times 10^{ - 7} {\text{m}}^{2} /{\text{h}} $$ ) represents the controlled release of KCl. Hence, the synthesized nanocomposite with controlled release and decent water retention can prevent the serious environmental hazards.

2 D materials show fascinating properties for their applications in advanced technology. Tungsten Diselenide (WSe2), a family of transition-metal dichalcogenides, has greatly inspired researchers to take up challenges in energy storage, optoelectronic and electronic applications. We have synthesized WSe2 using hydrothermal technique via the reaction of sodium tungstate and selenium power with the assistance of sodium borohydride, a reducing agent and N, N- dimethylformamide (DMF) and deionized water have been utilized as double solvent. The structural and the surface morphological properties of WSe2 have been studied using X-ray diffraction and Field Emission Scanning Electron Microscope (FESEM) which approve the high crystallinity and reveal the most thermodynamically stable Hexagonal phase of WSe2. The successful synthesis of this new class of 2D material motivated us to perform ion beam bombardment experiments for modifying its properties especially for energy applications.

Zirconia (ZrO2) has a unique property of changing the crystalline phase from monoclinic to cubic at a higher temperature. This leads to its versatile applications in the fields of nuclear reactors, oxygen detectors, solid oxide fuel cells etc. Yttria doped zirconia has been studied extensively for transformation and stabilization of its cubic phase at room temperature. Whereas, the reports on such accounts with calcium doping are rare. In present study, the crystalline structure of Ca-doped zirconia (8 mol % Ca) as prepared by the solid-state reaction technique and sintered at 1000 °C in air, is compared with that of pure zirconia. From the X-ray diffractometer patterns recorded in θ-2θ geometry, it is evident that the pure zirconia exists only in the monoclinic phase. Further, the XRD of Ca-doped zirconia and its Rietveld refinement revealed the stabilization of zirconia in the monoclinic and cubic phase. The cubic phase stabilization in zirconia at room temperature with calcium doping opened up the possibilities of tailoring its properties more precisely via ion implantation.

Bio-fabrication of silver nanoparticles, using stem extracts of Nepeta leucophylla and their photocatalytic degradation activity, has been undertaken. The synthesized silver nanoparticles are chara...

Silver nanoparticles containing superabsorbent nanocomposite based on grafted copolymer of Guar gum/polyacrylic acid (GG/Poly(AA)) have been are synthesized by two step free radical graft copolymerization using ammonium persulphate (APS) as initiator and N, N′–methylenebisacrylamide (MBA) as cross-linking agent. The synthesized nanocomposite superabsorbent is characterized using various analytical techniques, such as, ultraviolet–visible spectroscopy, Fourier transformed infrared spectroscopy, X-ray diffractometry, Field Emission Scanning Electron Microscopy, Energy dispersive X-ray spectroscopy and thermal gravimetric analysis. The UV–vis, EDX and XRD studies revealed that silver nanoparticles (AgNPs) are successfully incorporated inside the polymer of GG/Poly(AA). The grafted crosslinking of backbone guar gum with acrylic acid and incorporation of silver nanoparticles are confirmed from the FTIR spectrogram. In addition to this, effect of several synthesis parameters, such as, concentration of guar gum, concentration of monomer, initiator and cross-linker are also studied. Furthermore, under optimized reactions conditions the influence of several parameters like pH, temperature and time on swelling behavior of superabsorbent nanocomposite is studied in double deionized water and found to be 1700%. The swelling behavior of nanocomposite has been also inspected in various saline solutions. It is evident that the AgNPs/GG/Poly(AA) nanocomposite superabsorbent may be used for water absorption purpose in many applications.

Bioinspired silver nanoparticles were synthesized using nontoxic, eco-friendly, and novel root extract of Nepeta leucophylla. The reduction of silver nitrate salt into nanoparticles is perf...

We demonstrated a facile electrochemical and photocatalytic degradation of MB dye using eco-friendly nanocomposites based on reduced graphene oxide/silver nanowires (rGO/AgNWs). The deposition of rGO onto stainless steel (SS) has been performed by an electroplating method and then AgNWs are decorated onto rGO with uniform distribution and strong interactions. The synthesized nanocomposite has been characterized by various analytical techniques such as UV–Vis, XRD, FTIR, FESEM, EDX, Raman and TGA/DSC. The rGO/AgNWs nanocomposite is used as anode in electrochemical and as photocatalyst in photocatalytic degradation experiment. The effect of various parameters, type of electrolyte, pH, voltage applied, concentration of electrolyte on electrochemical degradation of MB dye is also investigated. Various nanocomposites with different wt.% of Ag is synthesized in order to explore the influence of AgNWs onto percentage degradation. The rGO/AgNWs with 9.5 wt% shows maximum percentage degradation for electrochemical and photocatalytic degradation of about 99 and 98.36%, respectively, due to the presence of AgNWs which enhance the conductivity and surface area. The rate constant and activation energy are also calculated from degradation kinetics studies. Hence, it is expected that the rGO/AgNWs nanocomposite is promising photocatalyst and electrode which may prove to be a noble material for environment remedial application.

In the present study, the green microwave assisted synthesis of gold nanoparticles imbedded in XG/Poly(AA) biodegradable nanocomposite for controlled delivery of amoxicillin has been reported. The evidence of in-situ synthesis of gold nanoparticles by plant extract of Nepeta leucophylla as reducing agent inside the polymer matrix, grafting of acrylic acid (AA) onto backbone XG, surface morphology, crystallinity, thermal properties and loading of amoxicillin inside the MW-AuNPs/XG/Poly(AA) nanocomposite are investigated using various characterization techniques, such as, UV–Vis, XRD, FTIR, TGA/DSC, FE-SEM, EDX, TEM, DLS and Nitrogen adsorption-desorption isotherms (BET studies). The biodegradation test of synthesized nanocomposite has been performed by soil burial method for 75 days. The evidence of biodegradability of MW-AuNPs/XG/Poly(AA) nanocomposite is confirmed by FTIR and FE-SEM micrographs. The release profiles of amoxicillin drug from synthesized nanocomposite has been investigated for different pH (2.4, 7.0 and 9.2) at 37 °C using Korsmeyer–Peppas model. Here, the maximum drug loading efficiency is found to be about 85% and release of drug is large in basic medium as compare to acidic and neutral. It is expected that the present work may provide a noble method for synthesis of biodegradable nanocomposite with decent antioxidant potential for controlled release of amoxicillin.

The general aim of this work was to study the effects of swift heavy ions on the properties of electrochemically synthesized Ag-polypyrrole composite thin films. Initially, polypyrrole (PPy) films were electrochemically synthesized on indium tin oxide coated glass surfaces using a chronopotentiometery technique, at optimized process conditions. The prepared PPy films have functioned as working electrodes for the decoration of submicron Ag particles on the surface of the PPy films through a cyclicvoltammetry technique. Towards probing the effect of swift heavy ion irradiation on the structural and morphological properties, the composite films were subjected to a 40 MeV Li 3+ ion beam irradiation for various fluences (1 × 10 11 , 1 × 10 12 and 1 × 10 13 ions/cm 2 ). Comparative microstructural investigations were carried out after the different ion fluences using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy and micro-Raman spectroscopy techniques. Raman and SEM studies revealed that the structure of the films became disordered after irradiation. The SEM studies of irradiated composite films show significant changes in their surface morphologies. The surface was smoother at lower fluence but craters were observed at higher fluence.

A facile electrochemical synthesis of Au-polypyrrole (Au-PPy) composite films has been reported. The synthesized composite films were irradiated with a 1.25 MeV Co-60 gamma radiation with doses ranging from 500 to 1500 kGy and the corresponding changes in structural properties of the composites were studied. The structural investigation of Au-PPy composite films were performed by using X-ray diffraction (XRD), scanning electron microscopy (SEM) and micro-Raman spectroscopic techniques. XRD studies showed the variation in peak intensities after gamma irradiation. Different parameters like crystallite size, micro strain, dislocation density and distortion parameters were calculated from XRD spectra. Observed results indicate the formation of an ordered system in the irradiated composite films. SEM micrograph showed significant interactions between the Au-particles and PPy film after gamma irradiation. Raman spectra show an overall increase in peak intensity after gamma irradiation.

In this work, polypyrrole (PPy) microspheroidals were synthesized by chronopotentiometry on conducting indium tin oxide (ITO) substrate. These prepared PPy microspheroidals were subjected to surface modification by Ag nanostructures using cyclic voltammetery (CV). The decoration of Ag nanostructures on PPy surface was characterized by UV–visible spectroscopy (UV–vis), X-ray diffraction (XRD), Fourier transform infrared (FTIR), energy dispersion X-ray spectroscopy (EDX) and scanning electron microscopy (SEM). SEM images show nanostar like structures with slight aggregation of Ag nanostructures on the PPy surface. The average particle size of PPy was found to increase from 7.3 to 30 nm after decoration with Ag nanostructure. Further, the XRD patterns shows a decrease in interchain separation and inter planar distance after the impregnation of Ag nanostructures in the PPy film when compared with pure PPy film. FTIR and Raman spectra displayed main vibrational bands; including the characteristic peaks. Raman spectra also show the signature of polaron and bipolaron states. Electrical conductivity of the Ag nanostructure decorated PPy microspheroidals has been measured by the two probe method. A possible mechanism for the formation of Ag-PPy nanostructure has been proposed.

We have electrochemically synthesized polyaniline nano fibers with optimized process parameters (viz. concentration of monomer and dopant, applied current density, deposition time, etc.) on ITO coated glass substrate. The nano fibers of polyaniline were subjected to UV Visible, SEM and Raman spectroscopy. UV Vis spectra show two prominent peaks at 317 and 418 nm, which confirm the presence of different forms of polyaniline. Raman spectra confirm the formation of polyaniline. SEM image of synthesized nano fibers showed a flower like structure with an isotropic growth rate. Copyright © 2012 VBRI press.

Total mass attenuation coefficient, total photon interaction cross-section, effective atomic numbers ( Z eff ) and electron densities ( N e ) of Aniline (C 6 H 5 NH 2 ), Cyclohexane (C 6 H 12 ), Glycerine (C 3 H 5 (OH) 3 ), Butyl alcohol N-(C 4 H 9 OH), DMSO – dimethyl sulfoxide (C 2 H 6 OS), Methyl ethyl-ketone (C 4 H 8 O), Xylene (C 8 H 10 ), Acetophenone (C 8 H 8 O) and Triethyl amine (C 6 H 15 N) have been measured at 59.54 keV energy photon emitted by 100 mCi 241 Am point source employing narrow beam transmission geometry. Obtained results have been compared with theoretically calculated values of XCOM (Berger and Hubbel, 1987) and FFAST ( Chantler et al., 2005 ). Mixture rule was employed to calculated theoretical mass attenuation coefficient values for each sample. Good agreement has been observed between experimental and theoretical values within experimental uncertainties.

In this report, a two step electrochemical synthesis of Au-polyaniline composite is explored. In the first step polyaniline film was deposited on the ITO coated glass substrate by using chronopotentiometery technique. Later, using CV the surface of as prepared film was decorated by Au particles to fabricate Au-polyaniline composite. The composite is characterized by Raman spectroscopy, XRD and SEM. The SEM analysis shows a uniform dispersion of Au particles on the porous polyaniline film. A Raman spectrum confirms the existence of polyaniline in different oxidation states, which are attributed to specific signatures of delocalized charge carriers. XRD spectra confirmed Bragg's reflection at various planes.

We report the effects of heavy ion irradiation on the optical, structural, and chemical properties of polyethylene terephthalate (PET) film used in commercial bottled water. PET bottles were exposed with 120 MeV Ni ions at fluences varying from 3 × 1010 to 3 × 1012 ion/cm2. The modifications so induced were analyzed by using UV-Vis, X-ray diffraction (XRD) and Fourier Transform Infrared (FTIR) spectroscopy. Substantial decrease in optical band gap is observed with the increase in ion fluence. In the FTIR spectra, most of bands are decreased due the degradation of the molecular structure. XRD measurements show the decrease in peak intensity, which reflects the loss of crystallinity after irradiation.

Investigations were conducted in 1960 to study effects of fast electron and gamma radiations and packaging films on respiratory rate, control of fungal deterioration, and subsequent refrigeration life of peaches. The fungi responsible for deterioration of peaches were also studied in vitro to determine if they were susceptible or resistant to ionizing (fast electron and gamma) radiations. Respiratory behavior of the fruits under normal as well as modified conditions was assessed with a Claypool and Keefer-type respirometer and Orsat-type gas analyzer. Two kinds of polyethylene films were used for packaging fruits. The fruits after treatments and packaging were stored at 40°F and 85 per cent relative humidity and at 75°F and 35 per cent relative humidity. Effects of ionizing radiations Peaches (var. Elberta) Fast electron and gamma radiation increased respiration and controlled fungus growth. A fungus study in vitro was conducted at ambient (75°F) temperature and relative humidity (35 per cent). The results obtained with fast electron radiation showed that the fungus inhibition effect of radiation was directly proportional to the dosage applied. Effects of ionizing radiations and packaging films Peaches (vars. Elberta and Gem) Peaches (var. Elberta) were packaged in Duratite (type of polyethylene) film and then were irradiated with fast electrons, while peaches (var. Gem) were irradiated with gamma rays before they were packaged in Duratite and another polyethylene film. In fast electron radiation experiments the CO2 accumulation inside the Duratite bags increased with the increasing radiation dosages; whereas in gamma radiation, dosages applied behaved similarly for both the films except that the levels of CO2 maintained in polyethylene film were lower than in Duratite film. At radiation dosage of 5 × 105 rad, injuries on peaches (var. Gem) were shown as brown areas on the surface of the fruit. Fast electron radiation dosages of 1 × 105 and 3 × 105 rad were effective in controlling fugus growth and in keeping fruit for longer periods of time than in controls and 5 × 105 rad treatment. The evaluation of marketable quality of the fruits in gamma radiation experiments was similar to that obtained with fast electron radiation with the exception that the gamma radiation dosage of 3 × 105 rad was best in controlling spoilage by fungi while the fast electron treatment of 1 × 105 rad was the best protective dosage. In general, fruits packaged in polyethylene seemed to be better protected than fruits packaged in Duratite bags. The fungi observed on peaches were predominantly Penicillium and Rhizopus species. In general it can be summarized that ionizing radiations (dose 1 to 3 × 105 rad) in conjunction with packaging in polyethylene bags increased the refrigerated life of fresh peaches by 15 to 20 days.