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Introduction: Polymetallic sulfides and heterostructures like CdIn2S4, CdZnS2, CuxS‐NiySz, Cu2CoSnS4, CoNi2S4, Zn0.76Co0.24S have been fabricated with various shapes and forms for new applications. Ternary copper cadmium sulfides (CuCdS2) are a p‐type semiconductor with a direct band gap of about 2.4 eV forms very good nanocrystals like copper sulfide could be potentially applied to optical and electronic applications. Knowing that the SILAR synthesis, optical, paramagnetic, dielectric properties, and annealing of copper cadmium sulfides have not been sufficiently investigated, they are extensively analyzed and studied in the present work. Objectives: CuxCd1−xS (x = 0, 0.5, and 1) nanoparticles have been synthesized on the base of functionalized nitrile butadiene rubber by SILAR method and characterized using scanning electron microscopy, x‐ray diffractometer, UV–visible spectroscopy, Fourier‐transform infrared spectroscopy, electron paramagnetic resonance spectroscopy, and Raman spectroscopy. Effects of cycles, reaction time, and precursor concentration on the particle size, crystal growth and structure, bandgap energy, dielectric and paramagnetic properties, elemental composition, and morphology were investigated. Methods: The synthesis of CuxCd1−xS nanocrystals was carried out into the obtained functional polymer matrix by SİLAR method. The functional polymer (FNBR) is a dark brown powder which contains ‐PO(OH)2 and ‐OPO(OH)2 functional groups and does not dissolve in organic and inorganic solvents, can be used as a very good stabilizer of nanostructures. The synthesis of CuxCd1−xS/FNBR nanocompsite was carried out in 3, 5, and 15 cycles. Results and discussion: In the process of ternary sulfide formation, the nucleation rate of CdS was high at the beginning of the reaction, while the growth rate and stability of CuS were high in the later course of the reaction. The average crystallite size of the nancrystallites has been increased from 1.13 nm to 7.39 nm by the increasing of the number of cycles from 5 to 15, respectively. It is explained by the inclusion of copper in the composition and getting more stable material. Copper cadmium sulfide nanostructures demonstrate wide band gap energy (~3.7 eV) in this work which is explained by the formation of nanosized particles in a limited volume of FNBR matrix. Conclusions: The synthesis of CuxCd1‐xS nanocrystals was carried out into the obtained functional polymer matrix by SİLAR method. Strong diffraction peaks corresponding to cubic CdS are found with low SILAR cycles. SEM images of CuxCd1−xS/FNBR nanocomposite show that the atomic percentage of Cu and Cd into the ternary sulfide is 20.19% and 0.61%, respectively. It is explained by the inclusion of copper in the composition and getting more stable material with low solubility products (Ksp) which is in good agreement with XRD results. The calculated band gaps are higher than that of bulk CdS, CuS, and CuCdS2. Larger band gap is usually reported for defects or structural disorders, which is in good agreement with XRD and Raman results. [ABSTRACT FROM AUTHOR]

CdxZn1−xS nanoparticles have been synthesized on the base of functionalized nitrile butadiene rubber (FNBR) by SILAR method and characterized by various techniques. Both binary and ternary sulfide nanocrystals have been obtained in the cubic phase with very high purity at room temperature. The average particle size decreased from 2.49 nm to 2.22 nm and then increased to 2.44 nm by the increasing of zinc concentration from 25 % to 50 % and 75 %. The calculated Young's modulus for (111), (220) and (311) planes are 97.84, 78.51 and 64.33 m2 N−1 for CdS and 95.84, 69.68, 53.42 m2 N−1 for ZnS, respectively. The band corresponding PO32− (977 cm−1) shifted to 969, 975, 972, 973, and 972 cm−1 upon the formation of CdS, ZnS, Cd0.5Zn0.5S, Cd0.75Zn0.25S and Cd0.25Zn0.75S nanoparticles into FNBR matrix, which is explained by Hooke's Law. EPR spectra of CdS/FNBR nanocomposite show broad and singlet asymmetric, isotropic symmetry (gx=gy=gz). The appearance of a new line in the 3518 G magnetic field is observed in both CdS and Cd0.5Zn0.5S compounds' spectra.The total mass loss of the samples NBR, FNBR, Cd2+ and Zn2+ ions containing FNBR are 93.76, 59.77, 60.03 and 57.79 %, respectively. High crystallinity is caused by complete interaction of metal ions with functional groups during the nucleation. [ABSTRACT FROM AUTHOR]

Zinc-aluminum-based layered double hydroxide-polyvinyl alcohol (ZnAl-LDH/PVA) nanocomposite has been synthesized by one-pot co-formation method. An intercalation approach was realized using (ZnAl LDH/PVA) nanocomposite as adsorbent and photocatalyst for adsorption and solar photodegradation of hazardous food dyes—tartrazine, ponceau 4R and patent blue V. The characterization of synthesized nanocomposite was carried out by XDR, SEM, FTIR and UV-Vis. The adsorption of dyes onto the synthesized adsorbent was carried out under different initial dye concentrations, pH, adsorbent weight and three different temperatures. The optimal pH for tartrazine, ponceau 4R and patent blue V was determined as 2.0, 7.0 and 2.0, respectively. The optimal temperature at optimal pH was 303 K after 40 min. Pseudo-first-order kinetic model, Langmuir and Temkin isotherm models were represented well for the definition of the adsorption mechanism of tartrazine. The adsorption of ponceau 4R and patent blue V on the ZnAl-LDH/PVA nanocomposite follows the Freundlich isotherm. The value of the slope of 1/n for ponceau 4R and patent blue V is more close to the unit (1/n = 0.668 and 0.768, respectively), which indicates the possibility of the adsorption process according to the Freundlich model. Because the adsorbent shows a photocatalytic property, after high effective sorption, the cyclic reusability of the sorbent was ensured by keeping the sample in its dye solution at 308 K in bright sunlight for 5 hours. The completely decolorized sorbent has shown high efficiency in subsequent sorption experiments. The prepared ZnAlLDH/PVA nanocomposite exhibited high effectivity in adsorption and photocatalytic experiment. The effect of pH condition, tartrazine concentration and temperature on adsorbance and photocatalysis performance was studied by XRD, FTIR and UV-Vis technics in detail. Using ZnAl-LDH/PVA nanocomposite, the sorption time of tartrazine was reached to 40 min. Cyclic reusability of adsorbent was achieved by the photodegradation of adsorbed dye compound from the nanocomposite. Most importantly, the photodegradable nanocomposite after sorption showed higher efficiency in the subsequent sorption process. This is explained by the layered structure of the nanoparticles and the anion exchange intercalation of the high molecular weight dye compounds. [ABSTRACT FROM AUTHOR]

In this study one-pot synthesis of zinc-aluminum mixed oxide/polyvinyl alcohol (ZnAl mixed oxide/PVA) nanocomposite and its adsorption behavior for efficient removal of lead (II) ions from aqueous solution were investigated. The synthesized nanocomposite was characterized by X-ray diffraction (XDR), Scanning electron microscopy (SEM), Fourier transform infrared (FTIR) and Ultraviolet-visible spectroscopes (UV-Vis) to study structural, optical properties, morphology and elemental composition. Two characteristic reflections of ZnO and Zn6Al2O9 phases were shown by the XRD pattern of the nanocomposite. Due to PVA strongly caped the particles, the subsequent growth of the nanoparticle was prevented and estimated as 10.5 and 7.8 nm for ZnO and Zn6Al2O9 crystallites, respectively. The concentration of Pb(II) in a solution was investigated by Inductively coupled plasma - optical emission spectrometry (ICP-OES). The optimum pH for the uptake of Pb(II) on ZnAl mixed oxide/PVA was 5.0. The removal efficiency of Pb(II) reached up to ∼97% after 180 min when 0.03 g ZnAl mixed oxide/PVA was added in 10 mL Pb(II) solutions which the concentration was 331.4 mg/L (10-3 M) at the condition of neutral pH and 298 K. Pseudo-second-order kinetic model and Freundlich isotherm were found to be the most suitable models to define the adsorption mechanism in this process. Thermodynamic parameters like ΔH°, ΔS°, ΔG° and Ea of the adsorption of Pb(II) ions onto ZnAl mixed oxide/PVA are estimated -72.98, −0.222, −6.737 and 25.956 kJ/mol at the condition of neutral pH and 298 K. After 9 cycles the % removal of Pb(II) ions reduced to 63.177%. [ABSTRACT FROM AUTHOR]

The synthesis of lead(II) sulfide nanocomposite based on nickel–chromium layered double hydroxide was accomplished by the mechanochemical method at room temperature. The obtained nanocomposites were characterized by powder X-ray diffraction, UV-VIS spectroscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy to estimate structural, optical and morphological properties. The PbS nanoparticles expanded the interlayer space of the layered double hydroxide, its crystal structure was destroyed, and the PbS nanoparticles attached to the surface affected the XRD result. [ABSTRACT FROM AUTHOR]

Introduction: Layered double hydroxides (LDHs) are widely studied anionite clays consisting of positively‐charged hydroxide nanosheets which is described by the general formula: [M(II)1−xM(III)x(OH)2][An−·mH2O], where M(II) and M(III) are the divalent (e.g., Mg2+, Zn2+, Ca2+, Co2+, Ni2+, etc.) and trivalent (e.g., Al3+, Fe3+, Cr3+, etc.) metal ions, An− and H2O is the interlamellar anion (e.g., Cl¯, Br¯, NO3¯, CO32¯, SO42¯, SeO42¯) for charge‐neutralization and hydrated state, respectively. They have been widely used in different industry sectors, in materials science and research. Polymer/LDH nanocomposites have gained significant attention in recent years. Carbon‐based nanomaterials, like fullerene, carbon nanotubes (CNT), graphene and graphene oxide have attracted significant attention. Fullerene molecules (C60, C70) are used as reinforcing material for polymers to improve their mechanical, thermal, optical, energy storage and charge transport properties. Objectives: C60‐doped ZnAl‐layered double hydroxide/polyvinyl alcohol nanocomposites were successfully synthesized and their photocatalytic activity for photodegradation of methylene blue (MB) synthetic dye was quantitatively analyzed by ultraviolet (UV) spectroscopy. The effect of C60 on the optical, structural, morphological properties, and photocatalytic activity of LDHs was investigated, and the impact of C60/LDH mass ratio and aging time on the properties was also studied. Methods: Fullerene‐doped ZnAl‐LDH/PVA nanocomposites were synthesized via urea hydrolysis and coprecipitation‐coformation method. First, 10 wt% PVA/water solution (40 mL) is added into the mixed solution containing 0.015 mol of Zn(NO3)2·6H2O and 0.005 mol of Al2(SO4)3·9H2O and titrated by 2 M of NaOH and 1 M of NaHCO3 mixed base solution to adjust pH 9. The obtained white slurry was shaken very hard and aged for 1 year. The obtained samples were marked by the mass percentage of C60 as 1% C60@LDH/PVA, 10% C60@LDH/PVA, 20% C60@LDH/PVA, and 60% C60@LDH/PVA. Results and Discussion: The basal spacing of C60‐doped ZnAl‐LDH was estimated to be 9.217 Å which is wide enough from the general LDH (~7.0 Å). The crystallite size of nanoparticles is 9.217 nm and ~6 nm by Scherrer's equation and Williamson–Hall method from the XRD data, respectively. Rice‐shaped 2D morphology was formed with 100 nm–2 μm width and 500 nm–10 μm in length by SEM. The maximal photodegradation efficiency was found with 20% of C60 doping (PD% = 96.98) after 360 min, where the sorption efficiency with this compound is very high (R% = 85.55). Conclusions: In the presented work, the effect of C60 on the optical, structural, morphological properties, and photocatalytic activity of LDHs was investigated, and the impact of C60/LDH mass ratio and aging time on the properties was also studied. For the identification of the photocatalytic activity of obtained C60/LDH nanocomposites, MB was used as a model pollutant and the efficiency of the Zn/Al LDH nanocomposite, with various quantities of fullerene, is also evaluated. [ABSTRACT FROM AUTHOR]

β-NiS nanoparticles (NPs) grown through SILAR technique into functionalized nitrile butadiene rubber (FNBR) were used for the synthesis of CuS-NiS/FNBR and Cu 1.8 S-Ni 3 S 4 /FNBR nanocomposites (NCs). The evaluated band gap decreased from 2.8 eV to 2.3 eV and 2.21 eV using 0.25 M of CuSO 4 × 5H 2 O and 0.5 M of CuCl 2 × 2H 2 O, respectively. The effect of copper precursors and concentration of Cu 2+ ions on the particle size, chemical composition of NCs and properties has been discussed in detail. Different structural phases of nickel sulfide and copper sulfide were obtained using NiS/FNBR nanocomposites as a precursor for ion exchange reaction by Cu 2+ ions. Properties of Cu x S-Ni y S z /FNBR and CuS-Ni y S z /FNBR nanocomposites obtained after modification have been studied and compared with initial nanocomposite of NiS/FNBR. The average particle size increased from 8.5 nm to 13.5 nm and 15 nm after ion exchange modification. By EPR spectrum the superhyperfine splitting is seen in the spectrum of CuS-Ni y S z /FNBR, A Cu = 107.3 G. In perpendicular section the bandwidth of the spectrum (ΔH) is equal to 930 G. Recording to SEM images very clearly imaged spherical nanoparticles have been observed. [ABSTRACT FROM AUTHOR]

This work covers the effects of annealing temperature on crystalline size, surface morphology, optical, structural and paramagnetic properties of NiS and Ni 3 S 4 nanostructures grown through SILAR technique into FNBR matrix. Annealing at low temperature was performed in air and vacuum for 8 h. X-ray diffraction results confirm structural phase transitions (like NiS→Ni 7 S 6 and Ni 3 S 4 →Ni 9 S 8 ) and oxidation processes (by the formation of NiO-SO 4 -H 2 O) after thermal annealing of nanocomposites (NCs) in a vacuum and in air, respectively. By EDX spectrum the average Ni:S atomic ratio is approximately 1:1 for as-prepared NiS, 1:0.89 for NiS annealed in a vacuum and 1:0.91 for NiS annealed in air. [ABSTRACT FROM AUTHOR]

Cu x S-Ni y S z /FNBR and CuS-Ni y S z /FNBR nanocomposites (NCs) were prepared from β-NiS/FNBR by ion exchange method and dielectric characterized. Dielectric properties of NCs were investigated at the temperature of 26 °C–120 °C in 120–10 6 Hz frequency range. With measuring electric capacity and resistance of the samples at different frequency we have studied the dielectric permittivity, dielectric loss tangent, dielectric modulus, conductivity, relaxation times and Cole-Cole plots were obtained. At 120 °C measurement temperature, some of the destruction processes in polymers affect to interfacial interaction between the polymer and particles surface. After high temperature measurement all three samples were cooled to room temperature and their dielectric measurements were carried out at room temperature. It is observed that at high measurement temperature some of carriers transfer from one energy level to another and the dipole orientation did not return completely to the previous situation. [ABSTRACT FROM AUTHOR]

Nickel sulfide nanostructures have been successfully prepared with two different sulfur sources like thiourea (S C(NH 2 ) 2 ) and sodium sulfide by the successive ionic layer adsorption and reaction (SILAR) method. The functionalized nitrile-butadiene rubber (F-NBR) was used as stabilizing agent for formation of nickel sulfide semiconductor nanoparticles. The nanoparticle sizes correspond to 8.5 nm and 7 nm using thiourea and sodium sulfide respectively. The as-synthesized NiS and Ni 3 S 4 nanostructures were characterized by XRD, SEM, EDX, UV–vis and FTIR spectroscopy methods. A systematic investigation of the final end products has been done to elucidate the formation mechanism at different experimental parameters. Using thiourea the optical band gap of NiS for 4, 6 and 8 cycles were determined to be 3.12, 2.93 and 2.81 eV, respectively. The optical band gap of Ni 3 S 4 for 6 and 8 cycles were determined to be 2.8 and 2.15 eV, respectively. [ABSTRACT FROM AUTHOR]

Convenient and environmentally friendly synthesis of Co 9 S 8 /PVA, Co x S y /EG and Co x S y /3-MPA nanocomposites were carried out in the presence of ultrasonic irradiation by the liquid phase synthesis of the sonochemical method. For the synthesis, cobalt acetate tetrahydrate [Co(CH 3 COO) 2 ·4H 2 O] and sodium sulfide (Na 2 S·9H 2 O) were used as a cobalt and sulfur precursor, respectively. Polyvinyl alcohol (PVA), ethylene glycol (EG) and 3-mercaptopropionic acid (3-MPA) were used as a capping agent and surfactant. The structural, optical properties and morphology of nanocomposites were characterized using X-ray diffractometer (XRD), Ultraviolet/Visible Spectroscopy (UV–Vis), Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The optical band gap of Co 9 S 8 /PVA is 1.81 eV and for Co x S y /EG is 2.42 eV, where the direct band gap of bulk cobalt sulfide is (0.78–0.9 eV). The wide band gap indicates that synthesised nanocomposites can be used in the fabrication of optical and photonic devices. The growth mechanisms of the Co 9 S 8 , CoS 2 and Co 3 S 4 nanoparticles were discussed by the reactions. The effects of sonication time and annealing temperature on the properties of the nanoparticles have been studied in detail. [ABSTRACT FROM AUTHOR]

Abstract: In this research work, we have presented a chemical method to elaborate the PbS, CuS nanocrystals embedded in a polymer composites matrix. We have used polyethylene and nitrile butadiene rubber PE/NBR as a support for synthesis of lead sulfide (PbS) and copper sulfide (CuS) nanocrystals. The size control and morphology of these (PbS and CuS) nanoparticles have been applied by the method of “layer by layer”. The obtained nanoparticles were characterized by X-ray diffraction (XRD), UV–Vis and Atomic Force Microscopy (AFM). UV–Vis spectroscopy was used to determine simple optical responses, getting the biggest transmittances of CuS and PbS nanoparticles. Measured size of CuS nanoparticles is approximately 5.5–90nm in different dose. X-ray diffraction (XRD) study confirmed the formation of cubic phase of PbS nanocrystals into the composite matrix. The size of PbS was estimated ∼9nm. The surface morphology and crystallite sizes were determined by Atomic Force Microscopy measurements. [Copyright &y& Elsevier]

In the present study the thermal behavior of phosphorus- and phosphorus/nitrogen-containing functional polymers was studied. The polymers were synthesized via oxidative chlorophosphorylation reaction of butadiene rubber and were subsequently subjected to hydrolysis, aminolysis and/or alcoholysis in order to introduce appropriate functionalities. The successful modifications of the polymer and presences of the respective functional groups were determined using Fourier transform infrared spectroscopy. It was found that the product of hydrolysis of the modified butadiene rubber contains acidic groups in its structure while the products of aminolysis and alcoholysis contain both acidic and amine and/or alcohol-derived moieties. The kinetic analyses of the thermal decomposition reaction were evaluated using thermogravimetric analysis and subsequently Friedman and Ozawa-Flynn-Wall methods revealing three-stage degradation process. Calorimetric measurements were performed for the studied polymers, and mass spectrometric analyses were used to identify the decomposition products for phosphorus-containing polymer. The overall results allowed to reveal the influence of the attached phosphorus- and phosphorus/nitrogen-containing functional groups to the thermal degradation of the cross-linked polymers. [ABSTRACT FROM AUTHOR]

The main goal of this study was the preparation of materials containing phosphoric func-tionalities on the base of industrial polymer - divinyl rubber and the assessment of their removal efficiency of heavy metals from aqueous solutions. The new method concerns the oxidative chlo-rophosphorylation of divinyl rubber by PCl3 with the following modifi cation of obtained inter-mediates to create -PO(OH)2, -OPO(OH)2 groups in the polymer chain. The obtained modifi ed polymers get some new properties such as complex formation and capability for ion exchange. The nature and distribution of phosphoric functionalities in the polymer were studied by the methods of NMRand FTIR- spectroscopy, thermal analysis and scanning electron microscopy. The sorption properties of synthesized polymers towards some cations (Cu+2, Ni+2, Co+2 and Zn+2) from water solutions have been tested. It has been shown that the metal removal efficiency of prepared material depends on pH of medium, initial concentration and type of metal ions. [ABSTRACT FROM AUTHOR]