V. V. Zagorskii

Sensor activity of thin polymer films containing lead nanoparticles

Thin poly(p-xylylene) films containing lead nanoparticles were prepared by vacuum deposition technique. The vapors of p-xylylene monomer and lead were condensed onto the surfaces cooled down to 80 K. Films thus obtained were characterized by electric conductivity measurements during film samples formation. Such metallopolymer films exhibit sensor activity in the presence of ammonia in the atmospheric air. The influence of air humidity and the co-operative effect of ammonia together with water vapors on film resistance were studied.

Cryosynthesis and properties of metal-organic nanomaterials

Abstract Materials containing metal nanoparticles have been obtained by co-deposition of metal and organic compound vapors onto a surface at 77 K. A new method to encapsulate the metal nanoparticles and mesogenic cyanobiphenyls in a polymer matrix has been developed. Co-condensates of metal vapors (Ag, Mg, Cd, Zn, Pb, Sm, Mn, Sn) with the p-xylylene monomers lead to the polymers at low temperatures. Globular metal particles of 5–8 nm in size encapsulation polymer films have been obtained. The particles size was estimated by means of transmission electron microscopy (TEM). UV-vis, IR and NMR spectroscopy were used to control the processes of nanomaterial preparation. Bimetallic Ag/Pb cryoorganodispersions with particle size of about 5 nm have been obtained. Properties of bimetallic mixed clusters have been computed by ab initio quantum chemistry techniques.

Cryochemical synthesis and physical-chemical properties of nano-dispersed metallopolymers

Abstract New nanodispersed metallopolymer (Ag, Na, Mg, Pb, Mn, Ca, Sm) films have been obtained via low temperature codeposition of metal and reactive paraxylylene monomer vapours at 100 K. Electric conductivity of the films were studied during the components codeposition,upon the samples annealing at 80–300 K and maintaining at constant temperature. With a rise in nanoparticle concentration in the polymer matrix, the conductivity tends to increase. The conductivity may be determined by tunnel transfer of charge carriers from one nanoparticle to another through a thin dielectric layer (up to 50 nm) of polymer matrix.

The kinetics of low temperature transformations of samarium complexes with 1,3,5-tri-tert-butylbenzene in the solid phase

Abstract Zerovalent samarium complexes with 1,3,5-tri-tert-butylbenzene were obtained by low temperature codeposition of metal and ligand vapours on the cold (77 K) surface under vacuum. The formation of two complexes was stated. The kinetics of thermal decomposition of complex with characteristic band at 967 cm−1 was investigated. It was shown that the retarded kinetics takes place. An effective activation energy was calculated from the initial rates. Its value is 8 kJ/mol, which is typical for diffusion controlled reaction.

Solid state interaction of butyl halides with magnesium

Abstract The Mg – n-BuCl, Mg – n-BuBr and Mg – n-BuI systems by electrical conductivity, gas chromatography (GC) and UV-spectral method was investigated. The systems were obtained by chemical vapour deposition (CVD) method.

The cryosynthesis and gas sensitive properties of nanostructural sulfidized lead films

Nanostructured sulfidized lead films were prepared by cryoformation with modification of the surface by hydrogen sulfide and lead sulfide. Such films were compared with oxidized lead films. Sulfidized nanosystems had higher sensitivity to water vapor. The influence of water vapor on the electrical conductivity of condensates was studied. The morphology and microstructure of condensates were found to influence gas sensing properties.

Reactions of Solid Organic Compounds with Metal Species

Abstract The results on chemical reactions of metal atoms, small clusters and nanoparticles with different organic and inorganic substances in the temperature range 12–300 K are presented. Complexation and reactions of atoms and clusters of magnesium, samarium and silver with alkyl halides, carbon dioxide, ethylene and some mesogenic cyanophenyls were studied by the technique of matrix isolation and low temperatrure co-condensation of metal and ligands vapours, low temperature UV-Vis, IR-and ESR-spectroscopy in the combination with quantum chemistry calculations. In some cases the reaction products were analysed by high performance gas chromatography. It was shown that cryochemical reactions of metal particles of different size reflected the system redundant energy.