[Show abstract][Hide abstract] ABSTRACT: CuInS2 (CIS) nanoparticles (nps) were synthesized via a microwave approach by adding eight sulfur sources with a new copper precursor, [bis(acetylacetonato)copper(II)]; [Cu(acac)2]. The products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, ultraviolet–visible and photoluminescence spectroscopy. Band gap of as-synthesized nps was 2.1 eV that showed about 0.55 eV blue shift in comparison to its bulk type. As observed in other semiconductor systems, the optical absorption blue shift is associated with quantum confinement effects. Thin film of CIS was prepared by doctor’s blade technique and solar cell made from indium transparent oxide/CIS/CdS/Pt layers. I–V characterization was investigated for this cell and fill factor, open-circuit voltage (V
oc) and short-circuit current (I
sc) were achieved.
[Show abstract][Hide abstract] ABSTRACT: Sr2CuMgFe28O46 nanoparticles, a novel X-type hexagonal ferrite, were synthesized by a Green sol gel method. The reduced graphene oxide (RGO)/Sr2CuMgFe28O46 nano-composite was fabricated without any reduction agent. The Sr2CuMgFe28O46 nanoparticles and RGO/Sr2CuMgFe28O46 nanocomposite were characterized by XRD, EDS, FE-SEM, SEM, PSA and VSM. Sr2CuMgFe28O46 nanoparticles were spherical shaped with hexagonal ferrite structure and grain size of 7-27 nm, approximately. The magnetic measurements revealed that their hard ferrite character at room temperature and the saturation magnetization (M-s) and coercivity (H-c) of Sr2CuMgFe28O46 nanoparticles were 43.3 emu g(-1) and 3787 Oe, respectively. As expected, the magnetic response of the (RGO)/Sr2CuMgFe28O46 nanocomposite was lower than for Sr2CuMgFe28O46 nanoparticles.
Ceramics International 09/2014; 40(8):11957-11961. DOI:10.1016/j.ceramint.2014.04.032 · 2.61 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In this work, poly vinyl alcohol–ZnO nanocomposites were synthesized via two different in situ and ex-situ methods. In ex-situ, at first zinc oxide nanostructures were synthesized by one-step precipitation reaction between zinc acetate and sodium hydroxide. The effect of different surfactants such as poly vinyl pyrrolidone, poly vinyl alcohol and poly ethylene glycol on the morphology of ZnO nanostructures was investigated. Nanostructures were characterized by X-ray diffraction, scanning electron microscopy. The influence of ZnO nanostructures on the flame retardancy of the poly vinyl alcohol matrix was studied using underwriter laboratories UL-94 analysis.
[Show abstract][Hide abstract] ABSTRACT: We propose an innovative approach to impart graphene properties to the surface of thin-film composites polyamide. Specifically, biocidal properties were obtained by covalently binding graphene to the polyamide surface. Grafting of polymer onto graphene generate nanocomposites, which heighten anti-bacterial property by changing on morphology and graphene structure. Purpose of this survey is studying the degradation of bacteria wall by grafted graphene to polyamide. In this study, the graphene should be functionalized in order to boost the side activities, antitoxin property and dispersion in solution. Then, the covalent bonds are established between graphene and polyamide by a linkage function such as ethylendiamine. The result of grafting polymer has been characterized by TGA, SEM and XRD and evaluated for the anti-bacterial property of grafted polymer by analysis on E.Coil bacteria cells. The test of bacteria in present of grafted polyamide lead to destruction of 62% of bacteria in 1 hr.
[Show abstract][Hide abstract] ABSTRACT: Copper indium sulfide, CuInS2, nanocrystals were synthesized by a new precursor complex, [bis(2-hyroxyacetophenato)copper(ΙΙ)], [Cu(HAP)2], via a microwave method. The effects of sulfur sources, solvents, heating time and microwave power on morphology of product were investigated. The as-synthesized CuInS2 nanoparticles were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet–visible (UV–vis) spectroscopy, and room temperature photoluminescence (PL) spectroscopy. The nanoparticles of CuInS2 were used to prepare CuInS2 film by doctor's blade technique. The fill factor (FF), open circuit voltage (Voc), and short circuit current (Isc) were obtained by I–V characterization.
[Show abstract][Hide abstract] ABSTRACT: Magnetic nanoparticles were prepared by the aqueous co-precipitation method. The magnetic nanoparticles obtained were characterized systematically through the use of an X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), scanning electron microscope (SEM), transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FT-IR) and a vibrating sampling magnetometer (VSM). The results revealed that the magnetic nanoparticles were spherical shaped with inverse spinel structure. The size of Fe3O4 and Nd-Co doped Fe3O4 magnetic nanoparticles were approximately 15 nm. Magnetic measurement revealed that the nanoparticles were super paramagnetic at room temperature. It was found that the magnetic response of the Fe3O4 increased when it was doped with Nd3+ and Co2+. However, the magnetic response of the Fe3O4 decreased when it was doped with Nd3+ or Ce3+ or Cr3+or Ni2+. KEYWORDS: Fe3O4, Magnetic nanoparticles, Superparamagnetic, Magnetite, Fe3O4 doped Bull. Chem. Soc. Ethiop. 2013, 27(1), 49-56.DOI: http://dx.doi.org/10.4314/bcse.v27i1.5
Bulletin of the Chemical Society of Ethiopia 12/2012; 27(1). DOI:10.4314/bcse.v27i1.5 · 0.58 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In the title compound, C(16)H(22)N(3)OP·H(2)O, the P atom adopts a distorted tetra-hedral environment with the bond angles around the P atom in the range 99.98 (7)-116.20 (7)°. The P-N bond length in the [(CH(3))(2)N]P(O) fragment [1.6392 (14) Å] is slightly shorter than two other P-N bonds [1.6439 (15) and 1.6530 (14) Å]. In the (CH(3))(2)NP(O) fragment, one of the methyl groups is syn to the P=O bond, whereas the other one is anti to the P=O bond [C-N-P=O torsion angles = 4.80 (17) and -174.57 (15)°]. In the crystal, the water mol-ecules form hydrogen bonds to the O atoms of the P=O bond of two different mol-ecules and act as acceptors for the two amino H atoms of the same mol-ecule. As a result, chains parallel to  are formed.
[Show abstract][Hide abstract] ABSTRACT: The polyethylene fibers containing Ag nanoparticles were prepared through the chemical reduction under ultrasound irradiation. The effect of reducing reagent, power of ultrasound irradiation, reaction time and temperature in growth of the nanometric Ag were studied. Particle sizes and morphology of nanoparticle are depending on power of ultrasound irradiation. Results show a decrease in the particles size as increasing power of ultrasound irradiation. Also, an increase in temperature led to increase of particle size. The polyethylene fibers containing Ag nanoparticles were characterized with powder X-ray diffraction (XRD) and scanning electron microscopy (SEM).
[Show abstract][Hide abstract] ABSTRACT: PbS and Bi2S3 nanostructures were synthesized successfully via a microwave approach. For synthesis of PbS nanoparticles, a new precursor, [bis(salisylate) lead (ΙΙ)]; [Pb(Hsal)2] was used. The products were characterized by X-ray diffraction, scanning electron microscopy, and photoluminescence spectroscopy. Thin film of Bi2S3 was prepared by doctor’s blade technique and solar cell made from ITO/Bi2S3/PbS/Pt layers. I–V characterization was investigated for this cell and fill factor, open circuit voltage and short circuit current values were obtained.
[Show abstract][Hide abstract] ABSTRACT: The growth of silver bromide nanoparticles on polyester fiber was achieved by sequential dipping steps in alternating bath of potassium bromide and silver nitrate under ultrasound irradiation. The effects of ultrasound irradiation, concentration and sequential dipping steps in growth of the AgBr nanoparticles have been studied. Particle sizes and morphology of nanoparticle are depending on power of ultrasound irradiation, sequential dipping steps and concentration. These systems depicted a decrease in the particles size accompanying an increase in the sonication power. Results suggest that an increasing of sequential dipping steps and concentration led to an increasing of particle size. The physicochemical properties of the nanoparticles were determined by powder X-ray diffraction (XRD) and scanning electron microscopy (SEM).
[Show abstract][Hide abstract] ABSTRACT: Zeolite framework stabilized erbium(III) and thulium(III) complex nanoparticles was prepared for the first time by using a two step procedure: the ion exchange of Ln3+ (Ln: Er and Tm) with the extra framework Na+ ions in zeolite-Y, the template synthesis of 2,6-diformyl-4-methylphenol with different diamines. Analysis of the data indicated that the Ln(III) complexes has been encapsulated within the nanocavity of zeolite Y and exhibit different property from those of the free complexes, which can arise from distortions caused by steric effects due to the presence of sodium cations, or from interactions with the zeolite matrix.
[Show abstract][Hide abstract] ABSTRACT: In the title compound, C(14)H(18)N(3)OP, a crystallographic mirror plane bis-ects the mol-ecule (the C,N,C atoms of the dimethyl-amido moiety and the P=O unit lie on the mirror plane). The P atom has a distorted tetra-hedral geometry; the bond angles at P are in the range 98.98 (11)-115.28 (7)°. In the crystal, the O atom of the P=O group acts as a double hydrogen-bond acceptor for two symmetry-equivalent N-H⋯O hydrogen bonds, building  chains containing R(2) (1)(6) loops.
[Show abstract][Hide abstract] ABSTRACT: Dibutylphthalate has been prepared via esterification reaction in the presence of some solid acidic catalysts. Transition metal polyoxometalates with Keggin (K3[PMo6W6O40], K 3[PMo12O40], K4[SiMo 12O40], K4[SiW12O40], Na7[PW11O39]), Wells-Dawson (K 6[P2W18O62]), and Preyssler structures (K14[NaP5W30O110]) have been synthesized and characterized. The reactivity of these catalysts has been studied for the preparation of dibutylphtalate by esterification reaction of phthalic anhydride and 1-butanol. Among the various acidic catalyst used, K 3[PMo6W6O40] showed the best reactivity and efficiency compared to other catalysts.
[Show abstract][Hide abstract] ABSTRACT: The crystal structure of the title compound, (C6H12N5O)(4)-[W-12(SiO4)O-36]center dot 6H(2)O, consists of an alpha-Keggin-type [W-12(SiO4)O-36](4-) polyoxidoanion, four [(2H-tetrazol-5-yl)methyl]morpholinium cations and six uncoordinated water molecules. In the cations, the morpholine rings display chair conformations. Extensive N-H center dot center dot center dot O, N-H center dot center dot center dot N, O-H center dot center dot center dot O and O-H center dot center dot center dot N hydrogen bonds are present in the crystal structure.