Yu. M. Yukhin

Carbon monoxide semiconductor sensors based on SnO2-Bi2O3

Gas-sensitive (sensory) properties of bismuth-tin oxide materials, including ceramic films with the Bi2Sn2O7 composition and pyrochlore structure, were considered, as applied to the determination of H2, CO, and CH4 in an air mixture.

Fluorite-related phases in the Bi2O3–SO3 system

Abstract An investigation of the Bi 2 O 3 −SO 3 system with Bi 2 O 3 /SO 3 ratio (3–12):1 was carried out using X-ray powder diffraction, infrared spectroscopy and impedance measurements. New bismuth oxysulfate phases Bi 9 SO 16.5 (4.5:1) and Bi 15 SO 25.5 (7.5:1) are found. Their structures are interpreted as fluorite-related superstructures with lattice parameters: a 0 =11.024 A, c 0 =28.262 A and a 0 =16.440 A, c 0 =28.835 A for Bi 9 SO 16.5 and Bi 15 SO 25.5 , respectively. Some physical and chemical properties of these compounds were investigated including impedance and ionic conductivity.

Synthesis of silver nanoparticles via reduction of silver carboxylates by ethylene glycol

The products formed within the reduction of silver butyrate, capronate, caprylate, and stearate by ethylene glycol are explored via chemical, X-ray phase and differential thermogravimetric analysis, as well as electron microscopy and X-ray photoelectronic spectroscopy. It is shown that the reduction of these silver carboxylates by ethylene glycol is a promising method for synthesis of silver nanoparticles.

Precipitation of bismuth(III) salicylates from mineral acid solutions

Powder X-ray diffraction, IR spectroscopy, Raman spectroscopy, thermogravimetry, and chemical analysis were used to study the precipitation of bismuth(III) salicylates from perchloric, nitric, and hydrochloric acid solutions as dependent on the salicylate ion concentration, temperature, and pH. Depending on the synthesis parameters, precipitation from perchloric and nitric acid solutions yields monosalicylate BiOC7H5O3 or disalicylate Bi2O(C7H5O3)4.

Conductive inks for inkjet printing based on composition of nanoparticles and organic silver salt

In this article, conductive inks for inkjet printing with high content of silver nanoparticles with the addition of organic silver salt and polymer additives are developed and investigated. Silver nanoparticles are shown to be stably dispersed in a solvent and the presence of a silver salt and a polymeric surfactant ensures the viscosity necessary for printing. A print of test images is performed using a laboratory inkjet printer equipped with an industrial small-droplet printhead followed by annealing of printed patterns at 150–250°C, and their structural and electrical properties are investigated. Simultaneous presence of polymer additives and silver salt is found to influence the structure of the forming conductive layer and the conducting properties.

Tunneling of 6s 2 electrons in PbO and Bi2O3: XANES spectroscopy and DFT calculations

The results of XANES spectroscopy and DFT calculations are evidence for the occurrence of anomalous 2p2/3→6s1/2 electronic transitions in lead(II) and bismuth(III) oxides. The observed transitions may be due to the tunneling of outer 6s2 electrons.

Synthesis and structure of bismuth(III) oxohydroxocarboxylates

The structure and thermal transformation of bismuth(III) oxohydroxocarboxylates Bi6O4(OH)4(CnH2n − 1O2)6, where (CnH2n − 1O2) is a carboxylate ion and n = 2 (2–9, 11), were studied by X-ray powder diffraction, thermogravimetry, IR spectroscopy, and chemical analysis. The conditions of precipitation of bismuth carboxylates from perchlorate solutions were determined. The compounds have a layered structure and undergo the same phase transformations on heating.

Morphologic characteristics of bismuth and silver particles formed upon the reduction of metal stearates with benzyl alcohol

The products of the reduction of individual and mixed bismuth oxohydroxostearate and silver stearate with benzyl alcohol are studied by electron microscopy and X-ray powder diffraction. The reduction of mixed bismuth and silver carboxylates with benzyl alcohol is a promising route to both individual submicronzised bismuth and silver metal powders and to their alloys.

Specific features of polyol synthesis of silver nanoparticles with the use of solid carboxylates as precursors

Electron microscopy, X-ray diffraction, and chromatography-mass spectrometry have been employed to investigate the reduction of solid silver caprylate in ethylene glycol with the formation of silver nanoparticles. The structural characteristics of silver nanoparticles have been studied as depending on the conditions of their synthesis, including temperature, reduction time, and silver salt concentration. It has been found that, in the studied range of parameters under the conditions, when solid silver caprylate is dispersed in ethylene glycol, the characteristics of resulting nanoparticles are almost independent of the synthesis temperature. This peculiarity is related to the fact that the formation and growth of nanoparticles occur on the surface of silver salt crystals and are accompanied by gradual dissolution thereof. In this system, ethylene glycol plays the roles of a reductant and a solvent for liquid reaction products.

Interaction of bismuth(III) oxide with formic acid solutions

The interaction of bismuth(III) oxide with formic acid solutions at 22 and 55°C was studied using X-ray powder diffraction, thermogravimetry, electron microscopy, IR spectroscopy, and chemical analysis. Solubility curves were found to comprise two branches due to formates of compositions Bi(COOH)3 and BiOCOOH forming in the system. Thermal decomposition of bismuth formates is shown to be a promising route for the synthesis of metallic bismuth, as well as of tetragonal (β) and monoclinic (α) bismuth oxides.