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Çoban, Mustafa Burak (Balikesir Author), CdO and CdO:F films were prepared by ultrasonic spray pyrolysis method on glass substrates at temperature of 250 +/- 5 degrees C. The structural and optical properties of pure and fluorine doped CdO films were characterized by XRD measurements and UV-VIS spectra, respectively. X-ray diffraction patterns show that the films have the polycrystalline structure with preferred orientation along (111) plane. Scherrer Method and Williamson Hall Method were used for calculating of the crystalline grains and strains of films. It is observed that the films at 8% F doped has better crystallinity level, and F doping decreases the defects in CdO films and improves crystallite quality. By UV-VIS spectra, it is revealed that the film with 8% F doped has a high transmittance about 65% in the visible region together with a direct band gap of 2.70 eV. Thicknesses, refractive indices and extinction coefficient values are determined by spectroscopic ellipsometry technique using Cauchy-Urbach model., Research Fund of Dumlupinar University, Kutahya, Turkey 2011-5

Nano- and meso-porous SnO2 powders doped with and without 1-10 wt% MoO3 have been synthesized by an ultrasonic spray-pyrolysis method employing a precursor aqueous solution containing tin (IV) chloride pentahydrate (SnCl4·5H2O), ammonium heptamolybdate and polymethylmethacrylate (PMMA) microspheres as a template, and the effects of MoO3-doping and the addition of PMMA microspheres on the structural, morphological and gas-sensing properties of SnO2 were investigated in this study. It is confirmed that control of the amounts of PMMA microspheres in the precursor solution was effective in realizing well-developed nano- and meso-porous structures of SnO2 by X-ray diffraction analysis, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and the measurement of specific surface area and pore size distribution using a N2 adsorption isotherm. Gas-sensing properties of their thick films (about 50 μm thick), which were fabricated by screen-printing to various gases (NO2, C2H5OH and H2) were tested in ambient air. The doped thick films showed a high response and selectivity to 5 ppm NO2 gas in the case of 10 wt% MoO3-doping in both nano- and meso-porous structures of SnO2. We observed that the presence of Mo species in SnO2 lattice can improve the sensor response and selectivity towards NO2 gas. The effect of the MoO3-doping on the sensing characteristics of these films towards NO2 was discussed., Sensors and Actuators B: Chemical, 147(2), pp.554-560; 2010

The solid-state pyrolysis of acetylenedicarboxylic acid, monopotassium salt at 300 degrees C in air results in bulk quantities of a micron-sized yet macroporous oxidized carbon, which inherently possesses high content of metal-binding sites, such as carboxylate groups, free radicals, and ether/hydroxyl units. Besides its high oxygen content, the solid is stable in water and does not leach or disorient, while it also exhibits an appreciable thermal stability, at temperature exceeding 200 degrees C in air. Several techniques including TEM/SEM, TGA, Raman/FT-IR, XPS, EPR, and potentiometric titrations were employed for the characterization of the solid. Furthermore, liquid phase adsorption experiments revealed that the material is an efficient heavy metal adsorbent due to the presence of diverse surface-accessible binding sites, showing unusually high metal uptake capacities for Pb(2+) and Cu(2+) ions (ca. 4.5 mmol g(-1)). Journal of Materials Science