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Cadmium zinc aluminum layered double hydroxides (CdZnAl-LDH) were synthesized by urea hydrolysis and co-precipitation method in polyvinyl alcohol (PVA) solution. Cadmium - zinc sulfide (CdZnS) nanoparticles were synthesized on the obtained nanocomposites by the direct sulfidation method both at room temperature (250C) and 400C, and the photocatalytic degradation was studied for the removing of m-cresol from aqueous solutions under visible light. Ultraviolet (UV) spectra, X-ray diffractograms (XRD), Energy-dispersive X-ray (EDX) and Fourier transform infrared (FTIR) spectra of the obtained nanocomposites were characterizated and the average size of nanoparticles was determined according to the Scherrer formula. The average crystallite size of CdZnAl-LDH/PVA, CdZnS@CdZnAl-LDH/PVA (250C), and CdZnS@CdZnAl-LDH/PVA (400C) nanocomposites is 14.25 nm, 19.05 nm and 16.5 nm, respectively. It was found that the degree of photocatalytic degradation of m-cresol from water was 18% with CdZnAl-LIH/PVA, 25% with CdZnS@CdZnAl-LIH/PVA (250C), CdZnS@CdZnAl-LIH/PVA (40°C) is 29% under visible light for 3 hours. [ABSTRACT FROM AUTHOR]

In this work fullerene (C60) was noncovalently doped to zinc–aluminum layered double hydroxide/polyvinyl alcohol (ZnAl–LDH/PVA) nanocomposites and the obtained samples were used for the photodegradation of methylene blue and congo red dyes from water solution. The structural, optical properties, surface morphology, specific surface area and chemical composition of C60 doped LDH were characterized by XRD, UV–Vis, PL, SEM, TEM and BET technique. The average crystallite size is increased from 8 to ~ 20 nm, and the dislocation density (δ) decreased from 0.0127 to ~ 0.003 nm2 by the increasing the amount of C60 doping 1% to 10%, 20% and 60%. Fullerene was used as a dopant and support material to improve the photocatalytic activity of LDH. The photodegradation parameters were determined with 1%, 10%, 20% and 60%wt of C60 doped LDH under visible-light. A complete photodegradation of MB (PD% = ~ 99%) on the nanocomposites occurred during 10 h irradiation The photodegradation rate constant (kapp) is 0.024 min−1 for CR onto 1% C60 doped ZnAl–LDH/PVA. The results show that noncovalent doped C60 into ZnAl–LDH/PVA matrix reduces the recombination of electron–hole pairs and increases the efficiency of the photocatalyst. [ABSTRACT FROM AUTHOR]

In the present investigation, pure and different concentrations (2%, 4%, 6%, 10%) of Ag-doped Co3O4 nanoparticles have been synthesized by the sonochemical method and subsequent calcination at different high temperatures. Structural, optical, morphological properties and elemental composition of synthesized nanoparticles have been characterized using X-ray diffraction, UV–visible spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, transmission electron microscopy and energy-dispersive X-ray spectroscopy. According to X-ray diffraction results, no peaks related to silver or silver oxide were observed in the diffractograms of doped samples. Blue shift was observed in the absorption curve of Ag-doped Co3O4 nanoparticles compared to undoped Co3O4 nanoparticles. From transmission electron microscopy measurements, 2%, 4% and 6% Ag-doped Co3O4 nanoparticles thermal annealed at 500 °C exhibit sphere-like and irregularly structured morphology, while 10% Ag-doped Co3O4 nanoparticles have a rhombohedral-like, hexagonal and spherical morphology. The dielectric constant value (ɛʹ) was found to decrease with increasing frequency and it can be explained by Maxwell–Wagner model. The value of the dielectric constant increased with increasing of temperature from 25 to 100 °C and the highest value was observed for Ag0.1Co2.9O4/PVA sample at 100 °C temperature. [ABSTRACT FROM AUTHOR]

Cotton growing, being an important agro-industrial object, is being improved through the introduction of new mechanisms to increase resistance to various external stress factors. Taking into account the previously studied phytohormones, the purpose of our study was to identify the effect of the salicylic acid derivative, dinitrosalicylic acid (DNSA), on the biochemical processes in the common cotton AP-317 genotype. It was established that low concentrations of DNSA-0.01 mM decreased production of NO radical, catalase and PPO activity, as well as absorption of phosphorus-anions from the nutrient medium, while higher doses of them has led to the stimulation of NO radical production, increased peroxidase activity, stabilized absorption of phosphorus anions. It was also found that at low concentrations of DNSA took place slightly activation of SOD activity, but not at relatively high concentration of DNSA. Electron paramagnetic resonance analysis of the root and leaf tissue of the plant showed an increase in the concentration of magnesium and iron ions when exposed to DNSA. It was also found that DNSA increased the concentration of lipid peroxide radicals at 0.1 mM in both tissues. [ABSTRACT FROM AUTHOR]

We have prepared cobalt sulfide (CoxSy) nanoparticles through a successive ionic layer adsorption and reaction (SILAR) method at room temperature. Co(NO3)2 ? 6H2O aqueous solution was used as a cobalt precursor, Na2S ? 9H2O and thiourea [(NH2)2CS] aqueous solutions were used as sulfur precursors. Functionalized nitrile butadiene rubber (FNBR) was used as a stabilizing agent for the formation of nanoparticles and contains -PO(OH)2 and -(O)PO(OH)2 acid groups. Obtained CoxSy/FNBR nanocomposites were annealed at 100°C in a vacuum for 6 h. The prepared nanocomposites were characterized by XRD, SEM, EDX, UV-Vis and FT-IR spectrometer. In case thiourea is used as asulfur source, mixed phases of Co3S4, CoS1.097 and CoS2 were obtained with the dominance of Co3S4 phase. A possible formation mechanism, physical and chemical stabilization into the functional polymer matrix (FNBR) for the growth processes have been discussed. [ABSTRACT FROM AUTHOR]

This paper described the synthesis of lead(II)sulfide (PbS) based nanocomposite on polyvinyl alcohol/magnesium-aluminum--layered double hydroxide (PVA/Mg-Al-LDH) composite film by a successive ionic layer adsorption and reaction (SILAR) method. To characterize the prepared sample was carried out using X-ray powder diffraction analysis (XRD), Ultraviolet-visible (UV-Vis) spectroscope, Scanning electron microscope (SEM), Energy-dispersive X-ray (EDX) spectroscope, and Fourier transform infrared (FT-IR) spectroscope was used. The optical absorption study confirmed when the PbS nanoparticles are dispersed in the PVA polymer matrix, they can well fit the interstitial spaces between the polymer chains and thus an increase in the optical conductivity. [ABSTRACT FROM AUTHOR]

In the present investigation, Cu x Co 3- x O 4 ( x = 0, 0.02, 0.04, 0.06, 0.1) nanoparticles have been synthesized by the sonochemical method and subsequent calcination at high temperature. The synthesized nanoparticles were further characterized using X-ray diffraction, UV-vis spectroscopy, FT-IR spectroscopy, Raman spectroscopy, transmission electron microscopy and energy-dispersive X-ray spectroscopy. The analysis results showed that nanoparticle size, band gap and photocatalytic activity of Cu x Co 3- x O 4 compounds change by altering the Cu doping content. According to the XRD study, no impurity peaks associated with copper or copper oxide phases were observed in the diffractograms of doped samples. The highest degradation of methylene blue dye under visible light was observed in the presence of Cu 0.02 Co 2.98 O 4 nanoparticles and found to be 87.51% after 330 minutes. This value increased with increasing the amount of photocatalyst and with decreasing dye concentration., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)