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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]

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]

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]

Zinc-aluminum based layered double hydroxide (ZnAl-LDH), -oxide (ZnO), -mixed oxide (Zn6Al2O9), and zinc-aluminum mixed oxide/polyvinyl alcohol (ZnAl-mixed oxide/PVA) nanocomposite have been synthesized. The samples were characterized using some analytical methods: Ultraviolet-visible spectroscopy, Fourier transforms infrared (FTIR) spectroscopy, x-ray diffraction (XRD), scanning electron microscopy, and energy-dispersive x-ray spectroscopy. The XRD patterns of ZnAl-LDH5M and ZnAl-LDH2M show the characteristic reflections of ZnO phase beside the hydrotalcite-like structure. Using NaHCO3 in the experiment, the precipitation speed of the sample was high and in this regard, the particle size of ZnAl-LDHurea(1) was 22.37 nm. ZnAl-LDH2M and ZnAl-LDH5M describe three optical band gaps with three different energies. For ZnAl-mixed oxide/PVA, there are two types of electronic transitions could exist at ZnO which attributed to the filled O2p orbital and that associated to the empty Zn 4s orbital, with the possibility of some Zn 4p orbital. Another electronic transition could exist for Zn6Al2O9 between the filled O 2p orbital and the empty Al 3s orbitals, with the additional possibility of some Al 3p orbital. The intense FTIR band at very low wavenumber is observed for only ZnAl-LDHurea(2) which attributed to the Zn-O-bound for brucite-like LDH structures. [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]