The scientific cooperation of the Boreskov Institute of Catalysis with the catalytic communities from various countries is effected in accordance with various forms
of cooperation: conducting joint seminars on catalysis, exchanging the information and appropriate materials, exchanging research fellows, visiting scientific centers,
and participating in congresses and symposia on theoretical and applied catalysis.
According to research programs, projects and grants, the fundamentals of catalysis are studied jointly with researchers from various universities, institutions,
research laboratories and companies. BIC collaborates fruitfully on a commercial basis with the leading companies from more than 20 countries, sells licenses,
know-how and performs research projects according to client requests.
Academician Valentin N. Parmon is the Russian representative in the European Federation of Catalytic Societies (EFCATS), Member of the International Association
of the Catalysis Societies (IACS).
Australia |
1 |
Greece |
2 |
Netherlands |
9 |
Austria |
4 |
Hungary |
1 |
Poland |
5 |
Belarus |
8 |
India |
4 |
Republic of Korea |
16 |
Belgium |
11 |
Ireland |
1 |
Slovenia |
1 |
Bulgaria |
7 |
Israel |
4 |
Spain |
4 |
Canada |
2 |
Italy |
16 |
Switzerland |
2 |
China |
25 |
Japan |
12 |
Sweden |
1 |
Czechia |
1 |
Kazakhstan |
3 |
Taiwan |
1 |
Denmark |
1 |
Lithuania |
2 |
Thailand |
1 |
Egypt |
2 |
Malta |
50 |
Tunisia |
1 |
Finland |
8 |
Mexico |
1 |
Ukraine |
6 |
France |
19 |
Mongolia |
1 |
UK |
5 |
Germany |
33 |
Montenegro |
1 |
USA |
8 |
Visits of foreign specialists to the Boreskov Institute of Catalysis in 2008
Belarus |
2 |
Hungary |
1 |
Serbia and Montenegro |
2 |
Bulgaria |
1 |
India |
3 |
Spain |
1 |
China |
7 |
Japan |
4 |
Republic of Korea |
6 |
Czechia |
1 |
Kazakhstan |
1 |
Ukraine |
3 |
France |
11 |
Netherlands |
6 |
UK |
3 |
Germany |
5 |
Saudi Arabia |
1 |
USA |
14 |
ITALY
The cooperation in the frame of the agreement between Russian Academy of Sciences (RAS) and National Council on the Scientific Research of Italy with The Istituto di Tecnologie Avanzate per l'Energia "Nicola Giordano"(CNR Institute of Advanced Energy Technologies "Nicola Giordano"), Messina on the Project “Materials with Enhanced Properties for Energy Conversionâ€. Coordinators: Prof. Yu. Aristov (BIC) and
Prof. G. Restuccia (Istituto di Tecnologie Avanzate per l'Energia "Nicola Giordano").
FRANCE
According to the agreement between RAS and CNRS BIC collaborates with the Institute de Recherches sur la Catalyse (Research Institute on Catalysis), Villeurbanne in the frame of the Russian-French European associated Laboratory on Catalysis headed by Acad. V. Parmon and Dr. M. Lacroix. The Laboratory was established by an agreement signed December 6, 2004 in Moscow by RAS and CNRS. Four areas of research were identified:
INDIA
In the frame of Indo-Russian Integrated Long Term Programme of cooperation in science and technology (ILTP) BIC collaborates with:
Coordinators on the Program "Catalysis" are Acad. V. Parmon and Dr. S. Sivaram.
GERMANY
The cooperation in the frame of the agreement between RAS and German Scientific Research Society (GSRS) with Fritz-Haber-Institut der Max-Planck-Gesellschaft, Berlin on the 27 Project "Development of in situ Methods for Study of Solid Surfaces" . Coordinators: Prof. V. Bukhtiyarov (BIC) and Prof. R. Schlögl (Fritz-Haber-Institut der MPG).
JAPAN
Bilateral agreement BIC - Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, on the Project "Adsorption and Chemical Reactions for Heat Transformation". Coordinators: Prof. Yu. Aristov (BIC), Prof. Y. Kato (Research Laboratory for Nuclear Reactors)
CHINA
The cooperation in the frame of Associated Research Laboratory which was established by an agreement signed December 4, 2004 by the
Boreskov Institute of Catalysis and Heilongjiang University, Harbin. Chief Executive officers of Laboratory are:
Prof. V. Bukhtiyarov (BIC) and Fu Hong-Gang (Heilongjiang University). Project "Synthesis and Modification of
ZSM-12 Zeolites. Zeolite ZSM-12 in Reaction of Naphthalene Alkylation with Methanol".
Coordinators: Prof. Wu Wei (Heilongjiang University), Prof. G. Echevsky (BIC).
KOREA
In the frame of the agreement between RAS and Korea Science and Engineering Foundation (KOSEF) BIC cooperates with Korea Institute of Science and Technology, Seoul,
Korea.
COOPERATION IN THE FRAME OF PROJECTS FINANCED BY INTERNATIONAL FOUNDATIONS
INTAS - SB RAS Supported Project
Electromagnetic Response Properties of Carbon Onions and Carbon Onion-Based Composites
Project Coordinator:
Dr. Ph. Lambin, Facultes Universitaires Notre-Dame de la Paix, Namur, Belgium
Participants:
Belarus State University, Minsk, Belarus; University of Joensuu, Finland; Institute for Technical
Physics and Materials Science, Budapest, Hungary; The Boreskov Institute of Catalysis,
Novosibirsk, Russia (Dr. V. Kuznetsov), Nikolaev Institute of Inorganic Chemistry,
Novosibirsk, Russia.
CRDF Project
Carbon Nanoreactor for Solid-State Synthesis of Novel Nanoscale Materials Based on
Nanocrystalline Oxides
Project Coordinators:
Prof. A. Volodin, The Boreskov Institute of Catalysis, Novosibirsk, Russia
Prof. K.J. Klabunde, Kansas State University, Manhattan, Kansas, USA.
EUROPEAN COMMUNITY SIXTH FRAMEWORK PROGRAM
I. International Partnership for a Hydrogen Economy for Generation of New Ionomer Membranes
Coordinator: Dr. R. Mallant, Energy Research Centre of The Netherlands, Petten, The Netherlands
Partners:
Daimler Chrysler; FuMA-Tech GmbH; CNRS Montpellier; Dohgyue Chenzhou New Materials Company; Shanghai Jiao Tong University, Shanghai, China; The Boreskov Institute of Catalysis, Novosibirsk, Russia (Prof. V. Bukhtiyarov).
II. Co-Processing of Upgraded Bio-Liquids in Standard Refinery Units
Coordinator: Dr. Y. Solantausta, VTT Processes, Espoo, Finland
Partners:
Rijksuniversiteit Groningen, The Netherlands; The Boreskov Institute of Catalysis, Novosibirsk, Russia (Prof. V. Kirillov); Uhde Hochdrucktechnik GmbH, Germany; BTG Biomass Technology Group BV, The Netherlands; University of Twente, The Netherlands; STFI-PACKFORSK AG, Sweden; Institute of Wood Chemistry, Hamburg, Germany; Slovenian Institute of Chemistry, Slovenia; Arkema SA, France; Helsinki University of Technology, Finland; ALMA Consulting Group SAS, France; Centre National de la Recherche Scientifique, France; Chimar Hellas SA, Greece; Albermarle Catalysts Company BV, The Netherlands; Metabolic Explorer, France; Shell Global Solutions International, The Netherlands.
III. Non-Noble Catalysts for Proton Exchange Membrane Fuel Cell Anodes
Coordinator:
Dr. G. Tsotridis, Institute for Energy, Joint Research Centre, Petten, The Netherlands
Partners:
Technical University of Denmark, Lyngby, Denmark; The Boreskov Institute of Catalysis, Novosibirsk, Russia (Acad. V. Parmon, Dr. O. Pestunova); Southampton University, UK; Technical University of Munich, Germany; Bavarian Center for Applied Energy Research; Umicore, AG & Co KG, Germany.
IV. Novel Materials for Silicate-Based Fuel Cells
Coordinator: Dr. Ch. Arguirusis, Technische Universität Clausthal, Clausthal, Germany
Partners:
University of Aveiro, Aveiro, Portugal; Foundation of Research and Technology Hellas, Greece; Katholieke University of Leuven, Belgium; Max-Plank Institute of Colloids and Interfaces, Munchen, Germany; The Boreskov Institute of Catalysis, Novosibirsk, Russia (Prof. V. Sadykov); Ceramics and Refractories Technological Development Company, Greece; Ceramiques Techniques et Industrielles, France.
EUROPEAN COMMUNITY SEVENTH FRAMEWORK PROGRAM
Reforming of Crude Glycerine in Supercritical Water to Produce Methanol for Re-Use in Biodiesel Plants
Coordinator: J. Vos, BTG BiomassTechnology Group BV, The Netherlands
Partners:
Acciona Servicios Urbanos, Spain; The Boreskov Institute of Catalysis, Novosibirsk, Russia (Prof. V. Kirillov); Rijksuniversiteit Groningen, The Netherlands; University of Maribor, Slovenia; UHDE High Pressure Technologies GmbH, Germany; SPARQLE International BV, The Netherlands.
NATO PROGRAMME: SCIENCE FOR PEACE
I. Solid Oxide Fuel Cells for Energy Security
NATO Country Project Director:
Prof. N. Orlovskaya, Drexel University, Philadelphia, USA
Partner Country Project Director:
Prof. O. Vasiliev, Frantcevych Institute for Problems of Material Science, Kiev, Ukraine
Project Co-Directors:
Prof. V. Sadykov, The Boreskov Institute of Catalysis, Novosibirsk, Russia
Prof. J. Irvine, University of St. Andrews, St. Andrews, UK|
Prof. N. Sammes, University of Connecticut, Storrs, USA
Prof. R. Hasanov, Azerbaijan State Oil Academy, Baku, Azerbaijan
Dr. A. Schokin, State Committee for Energy Saving of Ukraine, Kiev, Ukraine
Prof. John Kilner, Imperial College, London, UK.
II. Mixed Conducting Membranes for Partial Oxidation of Natural Gas to Synthesis Gas
NATO Country Project Director:
Prof. J. Frade, Departamento de Engenharia Cerâmica e do Vidro, Universidade de Aveiro, Aveiro, Portugal
Partner Country Project Director:
Dr. V. Kharton, Institute of Physicochemical Problems, Belarus State University, Minsk, Belarus
Project Co-Directors:
Dr. J. Irvine, School of Chemistry, University of St. Andreas, Scotland, UK
Dr. T. Norby, SMN, Universitetet i Oslo, Oslo, Norway
Dr. J. Jurado, Instituto de Cerámica y Vidrio, CSIC, Madrid, Spain
Prof. V. Sobyanin, The Boreskov Institute of Catalysis, Novosibirsk, Russia
Prof. V. Kozhevnikov, Institute of Solid State Chemistry, Yekaterinburg, Russia
Dr. L. Boginsky, Institute for Personal Development and Staff Retraining in New Areas of Techniques, Technologies
and Economics of the Belarus Ministry of Education, Minsk, Belarus.
III. Development of Electromagnetic Wave Absorbing Coatings Based on Carbon Onions
NATO Country Project Director:
Prof. Ph. Lambin, Facultés Universitaires Notre-Dame de la Paix, Namur, Belgium
Partner Country Project Director:
Dr. O. Shenderova, International Technology Center Raleigh, USA
Project Co-Directors:
Dr. V. Kuznetsov, The Boreskov Institute of Catalysis, Novosibirsk, Russia
Dr. I. Larionova, Real-Dzerzhinsk Ltd., Dzerzhinsk, Russia
Dr. S. Maksimenko, Belarus State University, Minsk, Belarus
Prof. A. Okotrub, Nikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia
NATO PROGRAMME: SCIENCE FOR PEACE AND SECURITY
Capture and Decontamination of Chemical & Biological Agents by Novel Catalysts and Millisecond Jet Reactors
Project Coordinator from a NATO Country:
Prof. P. Smirniotis, University of Cincinnaty, Cincinnaty, USA
Project Coordinator from a Partner Country:
Prof. A. Vorontsov, The Boreskov Institute of Catalysis, Novosibirsk, Russia.
INTERNATIONAL SCIENCE AND TECHNOLOGY CENTER (ISTC)
I. Development of Catalysts and Reactors for Syn-Gas Production from Diesel Fuel and for Selective NO>x Reduction with Syn-Gas in Diesel Exhausts
Project Manager from BIC Prof. V. KirillovII. Development of High-Performance Oxygen-Containing Membranes and Compact Syn-Gas Generators on Their Base
Project Manager from BIC Prof. V. SadykovIII. Synthesis and Investigation of the Metal Oxide Catalysts for Photocatalytic Degradation of Harmful Gases Resulted from Terrorist Acts and Man-Caused Catastrophes
Project Manager from BIC Prof. A. VorontsovIV. Catalytic Production of SO3 for Conditioning of Electrostatic Precipitators Using in Russia and the Newly Independent States (NIS)
Project Manager from BIC Prof. A. ZagoruikoV. Development of an Integrated Separator for Direct Reforming of Hydrocarbons in High-Temperature Fuel Cells
Project Manager from BIC Prof. Z. IsmagilovVI. Synthesis, Formation and Modification of (In)Organic Nanoparticles in Supercritical Fundamentals and Applications
Project Manager from BIC Prof. V. Anikeev.Страницы 4 - 4 из 14
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THE STATE OF THE COMPONENTS IN Cu-CeO2-ZrO2 CATALYSTS FOR SELECTIVE OXIDATION OF CO
V.P. Kolko, R.I. Gulyaev, E.M. Moroz, A.I. Boronin, G.R. Kosmambetova*, A.V. Guralsky*, P.Y. Strizhak*
(*Pisarzhevskii Institute of Physical Chemistry, Kiev, Ukraine)
Bull. Russ. Acad. Sci.: Phys., 72(8) (2008) pp. 1098-1103.
Cu–CeO2 catalysts deposited on a commercial ZrO2 support have been investigated. The catalyst composition has been optimized: the optimum copper content was found to be 5–10 wt % at a cerium oxide content of 23 wt %. The catalysts were investigated by X-ray diffraction analysis and X-ray photoelectron spectroscopy. According to the X-ray diffraction data, the support consists of the monoclinic ZrO2 phase and cubic CeO2 phase with an enlarged lattice parameter, while the catalysts contain CuO. The X-ray photoelectron data indicate the presence of a highly dispersed CuO2 phase interacting with cerium oxide and zirconia on the surface of the catalyst having the optimum copper content.
ACTIVITY AND STABILITY OF Ni/Al2O3 CATALYSTS IN CARBON DIOXIDE CONVERSION OF METHANE AS INFLUENCED BY ALKALI METAL OXIDE ADDITIVES (K2O, Na2O, Li2O)
S.A. Solov’ev*, R.N. Zatelepa*, E.V. Gubaren*, P.E. Strizhak*, E.M. Moroz
(*Pisarzhevskii Institute of Physical Chemistry, Kiev, Ukraine)
Russ. J. Appl. Chem., 80(11) (2007) pp. 1883-1887.
Properties of Ni/Al2O3 composites supported by synthetic cordierite ceramic block matrices of honeycomb structure in carbon dioxide conversion of methane in the presence of alkali metal oxides (K2O, Na2O, Li2O) were studied in comparison with those of GIAP-18 granulated catalyst.
THE PRODUCT OF THERMOBARIC TREATMENT OF Pt0.25Os0.75
S.A. Gromilov*, T.V. D’yachkova**, A.P. Tyutyunnik**, Yu.G. Zainulin**, A.I. Gubanov*, S.V. Cherepanova
(*Nikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia; **Institute of Solid State Chemistry, Yekaterinburg, Russia)
J. Struct. Chem., 49(2) (2008) pp. 382-385.
The products obtained from the Pt0.25Os0.75 nonequilibrium solid solution treated by the thermobaric procedure (1.5–2 GPa, 2000°C, 3 min) were investigated by X-ray powder diffraction. The phase compositions were evaluated from quantitative X-ray phase analysis, energy dispersion spectroscopy, and crystal-chemical analysis data for known Pt x Os1−x phases.
STRUCTURE OF NANOCRYSTALLINE PARTICLES OF METALLIC COBALT FORMED DURING THE REDUCTION OF Co3O4 OXIDE
S.V. Cherepanova, O.A. Bulavchenko, S.V. Tsybulya
J. Struct. Chem., 49(3) (2008) pp. 512-516.
X-ray diffraction is applied to investigate metallic cobalt obtained by the reduction of nanocrystalline particles of Co3O4. The particles of metallic cobalt have a high concentration of stacking faults, i.e., violations of the layer packing sequence ABABAB..., which is seen in X-ray diffraction patterns as anisotropic broadening of diffraction peaks. Simulation of the diffraction patterns of α-Co with a different concentration of stacking faults is carried out.
NANOCOMPOSITES INTERMETALLICS/OXIDES, PRODUCED BY MA SHS
N.Z. Lyakhov*, P.A. Vityaz*, T.F. Grigoryeva*, T.L. Talako*, A.P. Barinova*, I.A. Vorsina*, A.I. Letzko*, S.V. Cherepanova
(*Institute of Solid State Chemistry and Mechanochemistry, Novosibirsk, Russia)
Rev. Adv. Mater. Sci., 18(4) (2008) pp. 326-328.
MA SHS was used for preparation of oxide/intermetallics nanocomposites. Mechanochemical reduction of Fe2O3 was investigated in conditions of high dilution by iron and aluminium. It shows that excess of Al content significantly alters the process. Mechanical activation of mixture 60.9 wt % Fe + 26.6 wt % Al + 12.5 wt % Fe2O3 leads to formation of nanocomposite Al2O3/Fe/Al, and following SHS creates nanocomposite Al2O3/FeAl. XRD-patterns were obtained with URD-63 diffractometer. Microstructure was studied by scanning electron microscopy (a Camscan scanning electron microscope with a Link Analytical AN10000 energy dispersive X-ray analyzer, Link ZAF4-FLS software was used for quantitative analysis), and transmission electron microscopy (a JEM 1000x microscope).
VACANCIES ORDERING IN La3+1-xBa2+xFeO3-δ PEROVSKITES
A.N. Nadeev, S.V. Tsybulya, G.N. Kryukova*, I.S. Yakovleva, L.A. Isupova
(*GNF e. V., Berlin, Germany)
Z. Kristallogr. Suppl., 26 (2007) pp. 381-386.
Using powder X-ray diffraction the La3+1-xBa2+xFeO3-δ perovskite related solid solutions were investigated. A morphotropic phase transition from orthorhombic to cubic was shown for the sample with x ~0.3. High temperature XRD patterns of La0.2Ba0.8FeO3-δ obtained under air and vacuum revealed new diffraction peaks related to local ordering of the oxygen vacancies. Such ordering remained at room temperature only after cooling in vacuum.
WEAKLY BOUND OXYGEN AND ITS ROLE IN STABILITY OF SOLID SOLUTIONS La1-x Srx FeO3−δ
A.N. Nadeev, S.V. Tsybulya, V.D. Belyaev, I.S. Yakovleva, L.A. Isupova
J. Struct. Chem., 49(6) (2008) pp. 1077-1083.
In the present study high-temperature X-ray diffraction, thermal analysis, and mass-spectrometry have been employed for investigation of samples in the
La1-x Srx FeO3−δ family
NANOCRYSTALLINE TRANSITION ALUMINAS: NANOSTRUCTURE AND FEATURES OF X-RAY DIFFRACTION PATTERNS OF LOW-TEMPERATURE Al2O3 POLYMORPHS
S.V. Tsybulya, G.N. Kryukova*
Phys. Rev. B: Condens. Matter, 77(2) (2008) 024112-024125.
Low-temperature γ-, η-, and χ-Al2O3 polymorphs were studied by high resolution transmission electron microscopy and X-ray powder diffraction along with computer simulation of the diffraction patterns. Planar defects lying on the {111}, {110}, and {100} planes, which are the origin of the broadening of X-ray diffraction peaks in different forms of aluminium oxide, were revealed. In addition to providing strong experimental support for the imperfect character of the specimen structures, these results demonstrate the possibility of using nanosized crystalline domains with a spinel-type arrangement, which are regularly shaped and have a specified, developed face and bounding surfaces, for the description of the nanostructure of a whole variety of low-temperature Al2O3 derivatives. It was found that different ways of domain packing in the oxide particles with a subsequent formation of planar defects contribute to specific kinds of line-shape broadening observed in the X-ray diffraction patterns of these materials. The mechanism of the vacancy generation upon propagation of the shear-type defect in the {110} plane of the spinel structure, which changes the Al2O4 stoichiometry to Al2O3, is also discussed.
SYNTHESIS AND STUDY OF THE THERMAL STABILITY OF SrFe1-xMxO3-z (M=Mo, W) PEROVSKITES
O.A. Savinskaya*, A.P. Nemudry*, A.N. Nadeev, S.V. Tsybulya
(*Institute of Solid State Chemistry and Mechanochemistry, Novosibirsk, Russia)
Solid State Ionics, 179(21-26) (2008) pp. 1076-1079.
In the present work, solid solutions of the composition SrFe1-xMxO3-z, where M = Mo, W and 0 <x< 0.5, are synthesized. The structure of the new materials depending on the composition and on oxygen stoichiometry is studied; the results of high-temperature X-ray diffraction measurements, thermal stability and phase transformations in various environments are presented.
SOFT ACTIVATION OF THE C-S BOND: X-RAY DIFFRACTION AND SPECTROSCOPIC STUDY OF THE CLUSTER Ru4 (μ4-S)(μ,η3-C3H5)2(CO)12
I.Yu. Prikhod’ko*, V.P. Kirin*, V.A. Maksakov*, A.V. Virovets*, A.V. Golovin
(*Nikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia)
J. Struct. Chem., 49(4) (2008) pp. 719-723.
The complex Ru4(μ4-S)(μ,η3-C3H5)2(CO)12 is prepared and examined by IR and NMR spectroscopy; its crystal structure is determined (an automatic Bruker-Nonius X8 Apex four-circle diffractometer equipped with a 2-D CCD-detector, 100 K, graphitemonochromated molybdenum source, e = 0.71073 A). The crystal belongs to the orthorhombic crystal system with unit cell parametersa = 19.3781(9) A, b = 12.2898(7) A,c = 10.1726(4) A,V = 2422.6(2) A3, space group Pnma, Z = 4, composition C18H10O12Ru4S, d x = 2.343 g/cm3. The molecule of point symmetry C1 is situated on the mirror plane of the space group Pnma, two carbonyl groups at Ru2 and Ru3 atoms overlapping with the allylic ligand with a weight of 50% so that carbon atoms coincide. Thus, one has a racemic structure with two overlapping enantiomers of the molecule of Ru4(μ4-S)(μ,η3-C3H5)2(CO)12.
X-RAY PHOTOELECTRON STUDY OF THE INTERACTION OF H2 AND H2+O2 MIXTURES ON THE Pt/MoO3 MODEL CATALYST
A.V. Kalinkin, A.V. Pashis, V.I. Bukhtiyarov
J. Struct. Chem., 49(2) (2008) pp. 255-260.
The effects of H2 and H2 + O2 gas mixtures of varying composition on the state of the surface of the Pt/MoO3 model catalyst prepared by vacuum deposition of platinum on oxidized molybdenum foil were investigated by X-ray photoelectron spectroscopy (XPS) at room temperature and a pressure of 5–150 Torr. For samples with a large Pt/Mo ratio, the XP spectrum of large platinum particles showed that the effect of hydrogen-containing mixtures on the catalyst was accompanied by the reduction of molybdenum oxide. This effect results from the activation of molecular hydrogen due to the dissociation on platinum particles and subsequent spillover of hydrogen atoms on the support. The effect was not observed at low platinum contents in the model catalyst (i.e., for small Pt particles). It is assumed for the catalyst that the loss of its hydrogen-activating ability is a consequence of the formation of platinum hydride. Possible participation of platinum hydride as intermediate in hydrogen oxidation to H2 + O2 is discussed.
USE OF THE DIFFERENTIAL CHARGING EFFECT IN XPS TO DETERMINE THE NATURE OF SURFACE COMPOUNDS RESULTING FROM THE INTERACTION OF A Pt/BaCO3/Al2O3 MODEL CATALYST WITH NOx
M.Yu. Smirnov, A.V. Kalinkin, A.A. Dubkov, E.I. Vovk, A.M. Sorokin, A.I. Nizovsky, B. Carberry*, V.I. Bukhtiyarov
(*Ford Forschungszentrum, Aachen, Germany)
Kinet. Catal., 49(6) (2008) pp. 831-839.
A Pt/BaCO3/Al2O3 model NOx storage–reduction catalyst, which was prepared as a thin film (~100 A) on the surface of tantalum foil, was studied by X-ray photoelectron spectroscopy (XPS). It was found that the Pt/BaCO3 and Pt/Al2O3 catalyst constituents acquired different surface charges in the course of photoelectron emission; that is, differential charging occurred. An analysis of this effect allowed to determine the nature of the products formed in the interaction of the catalyst with a mixture of NO (260 Pa) +O2 (2600 Pa) + H2O (525 Pa) at 250°C followed by reduction with a mixture of CO (2100 Pa) + H2O (525 Pa) at 450°C. It was found that barium carbonate was converted into barium nitrate as a result of reaction with NOx on the surface of BaCO3. Simultaneously, platinum supported on both BaCO3 and Al2O3 was oxidized. The reduction of the catalyst treated with a mixture containing NO resulted in nitrate decomposition and regeneration of a carbonate coating on the surface of BaCO3; this is accompanied by the reduction of oxidized platinum particles to platinum metal.
COMPARATIVE STUDY OF RUBIDIUM AND CESIUM AS PROMOTERS IN CARBON-SUPPORTED RUTHENIUM CATALYSTS FOR AMMONIA SYNTHESIS
Yu.V. Larichev, D.A. Shlyapin*, P.G. Tsyrul'nikov*, V.I. Bukhtiyarov
(*Institute of Hydrocarbons Processing, Omsk, Russia)
Catal. Lett., 120(3-4) (2008) pp. 204-209.
Sibunit-supported Ru-catalysts promoted with cesium or rubidium compounds have been comparatively studied with XPS. The cesium promoter interacts both with support and with active component. The absence of the promoter-support interaction in the case of rubidium provides a stronger interaction between promoter and active component compared to the cesium-based catalysts. These differences in the promoter-support and promoter-metal interactions are exhibited when a sequence of ruthenium and alkali introduction are changed.
NEW OPPORTUNITIES FOR THE IDENTIFICATION OF OXIDE CLUSTERS IN SUPPORTED Ru/MgO CATALYSTS
Yu.V. Larichev, S.E. Malykhin
Kinet. Catal., 49(4) (2008) pp. 581-586.
The Ru/MgO systems were studied using XPS, transmission electron microscopy, and X-ray diffraction analysis. It was found that from 25 to 75% of the supported metal can occur in an X-ray amorphous form with a particle size of smaller than 3 nm. The insertion of supported metal ions into the support structure was absent. A comparison between the valence band XPS spectra and the corresponding densities of states calculated by quantum-chemical methods indicated that the X-ray amorphous portion of the metal can occur as both metal and oxide clusters depending on the precursor of ruthenium.
PHOTOELECTRON STUDIES OF ADSORPTION AND CATALYSIS ON THE SURFACE OF METAL SINGLE CRYSTALS AND POLYCRYSTALS
A.I. Boronin
J. Struct. Chem., 49 (Supplement) (2008) pp. 138-158.
The potential of photoelectron spectroscopy (XPS) and its use in studies of the state of the surface and adsorption processes on bulk metal samples (disk single crystals, polycrystalline foil and plates) are discussed. Methods for determining the electronic state of the surface layer and geometrical localization of adsorbed atoms on the metal surface using angle-resolved photoelectron spectroscopy are described. The spectrokinetic use of the dynamic mode of XPS with high accuracy and time resolution for kinetic studies of fast processes on the surface (adsorptiondesorption, reconstruction, reaction, diffusion-segregation) is considered in detail.
XPS, UPS, AND STM STUDIES OF NANOSTRUCTURED CuO FILMS
A.I. Stadnichenko, A.M. Sorokin, A.I. Boronin
J. Struct. Chem., 49(2) (2008) pp. 341-347.
A Cu1O1.7 oxide film containing a large amount of superstoichiometric oxygen was obtained by low-temperature oxidation of metallic copper in the oxygen plasma. An STM study of the film structure showed that ~ 10 nm planar copper oxide nanocrystallites are formed with particles packed parallel to the starting metal surface. In an XPS study, the spectral characteristics of the Cu2p and O1s lines indicated that particles with a CuO lattice formed (Ebnd(Cu2p3/2) = 933.3 eV and the presence of a shake-up satellite, Ebnd(O1s) = 529.3 eV). The additional superstoichiometric oxygen is localized at the sites of contact of nanoparticles in the interunit space and is characterized by a state with the binding energy Ebnd(O1s) = 531.2 eV. Due to the formation of a nanostructure in the films during low-temperature plasma oxidation, the resulting copper oxide has a much lower thermal stability than crystalline oxide CuO.
CHEMICAL VAPOR DEPOSITION AND CHARACTERIZATION OF HAFNIUM OXIDE FILMS
T.P. Smirnova*, L.V. Yakovkina*, V.N. Kitchai*, V.V. Kaichev, Yu.V. Shubin**, N.B. Morozova**, K.V. Zherikova**
(*Nikolaev Institute of Inorganic Chemistry, Novosibirsk Russia; **Tomsk State University, Tomsk, Russia)
J. Phys. Chem. Solids, 69(2-3) (2008) pp. 685-687.
HfO2 layers were grown on silicon by metalorganic chemical vapor deposition using (C5H5)2Hf(CH3)2, (C5H5) 2Hf(N(C2H5) 2) 2 and Hf(dpm)4 as volatile precursors and were characterized by IR, XP, ED-spectroscopy, X-ray diffraction, ellipsometry and electrophysical methods. The films were shown to consist of monoclinic HfO2 and to contain hafnium silicide and silicate at the HfO2/Si interface. The presence of hafnium silicide was attributed to oxygen deficiency induced by argon ion sputtering of the film during XPS analysis. Hafnium silicate was formed as a result of the reaction between hafnia and silicon oxides during annealing. Current-voltage and capacitance-voltage measurements on Al/HfO2/Si test structures were used to determine the dielectric permittivity and electrical resistivity of the films: k = 15-20, p = 1015Ω cm.
COMPOSITION AND STRUCTURE OF HAFNIA FILMS ON SILICON
T.P. Smirnova*, V.V. Kaichev, L.V. Yakovkina*, V.I. Kosyakov*, S.A. Beloshapkin**, F.A. Kuznetsov*, M.S. Lebedev*, V.A. Gritsenko***
(*Nikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia; **University of Limerick, Limerick, Ireland;***Institute of Semiconductor Physics, Novosibirsk, Russia)
Inorg. Mater., 44(9) (2008) pp. 965-970.
Ellipsometry, electron microscopy, and X-ray photoelectron spectroscopy data indicate that, during HfO2 deposition onto silicon, the native oxide reacts with the HfO2 deposit to form an amorphous intermediate layer which differs in refractive index (=1.6) from both HfO2 (1.9–2.0) and SiO2 (1.46). Thermodynamic analysis of the Si–SiO2–HfO2–Hf system shows that Si is in equilibrium with Si/HfO2-y only at low oxygen pressures. Starting at a certain oxygen pressure (equivalent to the formation of a native oxide layer), the equilibrium phase assemblage is Si/HfSiO4/HfO2-y.
PLASMA-CHEMICAL DEPOSITION OF SiCN FILMS FROM VOLATILE N-BROMHEXAMETHYLDISILAZANE
T.P. Smirnova*, A.M. Badalian*, V.O. Borisov*, L.F. Bakhturova*, V.V. Kaichev, T.A. Podgorbunskaya**, V.I. Rakhlin**
(*Nikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia; **Favorskii Institute of Chemistry, Irkutsk, Russia)
Inorg. Mater., 44(12) (2008) pp. 1312-1318.
Process of silicon-carbonitride (SiCN) film production from a new volatile organosilicon, N-bromhexamethyldisilazane, is developed. The use of this chemical comprising the relatively week N–Br bond makes it possible to increase the film growth velocity in the plasma-chemical process with remote plasma in comparison with the processes in which hexamethyldisilazane and hexamethylcyclotrisilazane are used. The chemical composition of the films is determined using a complex of spectroscopic methods. It is found that inorganic SiCN films containing Si–N, Si–C, and C–N bonds are deposited at temperatures 570–870 K. The C–N bonds are formed already at a temperature of about 470 K. It is shown that the use of this volatile organosilicon material makes it possible to synthesize silicon carbonitrides with various ratios of the Si–N, Si–C, and C–N bonds. This enriches the possibilities of producing films and coatings with various functional parameters. The nanohardness of 100-nm films prepared at T > 770 K is 17 GPa.
PHOTOLUMINESCENCE STUDY OF THE ELECTRONIC STRUCTURE OF HfO2 FILMS
A.A. Rastorguev, V.I. Belyi*, T.P. Smirnova*, L.V. Yakovkina*
(*Nikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia)
J. Struct. Chem., 49(1) (2008) pp. 21-30.
A method was developed for investigating hafnium dioxide films; this procedure uses a hydrogen-deuterium lamp as a source of photoluminescence (PL) excitation. Photoluminescence in HfO2 films was investigated. An analysis of the PL spectra of the films showed that they coincided with the spectra described in the literature and recorded using more powerful sources (synchrotron radiation or ArF laser). A comparison of obtained results with the literature data confirmed that the PL spectra of the films weakly depended on the type of the substrate used for the synthesis. The PL band intensity depends on the synthetic conditions and the annealing temperature. The authors analyzed the PL and excitation spectra and revealed an emission band at an energy E ~ 4 eV with a narrow excitation maximum at Emax =~ 4.25 eV, which was assigned to the vibronic resonance transition A 2Σ+ ↔ X 2Πi in the OH•* excited radical. Water was detected in the PL spectra of the HfO2 films; it is trapped as an impurity after thermal decomposition of Hf(dpm)4 in the course of film growth. The detection of water in the PL spectra of these films provides new insight into the problem of the effect of this impurity on the leakage currents and the importance of control over its content in the films.
LUMINESCENCE OF THE INTRINSIC AND EXTRINSIC DEFECTS IN HAFNIA FILMS
A.A. Rastorguev, V.I. Belyi*, T.P. Smirnova*, L.V. Yakovkina*, M.V. Zamoryanskaya**, V.A. Gritsenko***, H. Wong***
(*Nikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia;**Ioffe Physicotechnical Institute, St. Petersburg, Russia; ***Institute of Semiconductor Physics, Novosibirsk,
Russia; ****Department of Electronic Engineering, City University of Hong Kong, Kowloon, Hong Kong)
Phys. Rev. B: Condens. Matter, B76(23) (2007) pp. 235315-1-23515-6.
Both intrinsic and extrinsic defects of hafnium oxide films are investigated based on photoluminescence (PL) and cathodoluminescence (CL) measurements. Instead of using the high-power synchrotron radiation or ArF excimer laser sources, a hydrogen-deuterium lamp (HDL) was used for the PL measurements to avoid the possible generation of active oxygen and hydroxyl ions. Results show that the HDL PL spectra generally agree with those registered using the conventional high-power excitation sources. CL spectra also agree with the PL ones. Narrow emission band at peak energy of 4.0 eV, which is ascribed to the vibronic transition of excited OH·* radical, was found using photoluminescence excitation and at energy of 4.25 eV.
LUMINESCENCE OF HAFNIUM DIOXIDE FILMS PRODUCED FROM HAFNIUM DIPIVALOYLMETHANATE
V.I. Belyi*, A.A. Rastorguev
(*Nikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia)
Russ. Phys. J., 50(4) (2007) pp. 374-378.
A technique is developed for measuring luminescence spectra of hafnium dioxide using a hydrogen lamp as an excitation source. The luminescence spectra of the as-grown and annealed hafnium dioxide films prepared by chemical deposition from volatile hafnium dipivaloylmethanate on the Si(111) substrates are measured at room temperature. Intense luminescence at λ ~ 280 nm is characteristic of nanocrystallites of monoclinic modification. The band gap width is found to be ~ 5.76 eV. It is shown that the film composition significantly deviates from the stoichiometric one.
EXAFS STUDY OF THE LOCAL STRUCTURE AND CATION DISTRIBUTION IN V-Mo-Nb OXIDE
T.Yu. Kardash, D.I. Kochubey, L.M. Plyasova, V.M. Bondareva
J. Struct. Chem., 49(Supplement) (2008) pp. 116-123.
The local structure and cation distribution in Mo-Nb and V-Mo-Nb oxides with M5O14 type structures, which are active in the oxidative transformations of ethane, were studied by EXAFS spectroscopy. In the amorphous (or nanocrystalline) state, the oxides have fragments of the M5O14 structure in the form of stars of pentagonal MO7 bipyramids connected with MO6 octahedra along edges and arranged in a disordered matrix of octahedra. Possible crystallographic positions occupied by vanadium cations were revealed.
REFINEMENT OF THE CATION DISTRIBUTION IN Nb-Mo DOUBLE OXIDE
T.Yu. Kardash, L.M. Plyasova, V.M. Bondareva, A.N. Shmakov
J. Struct. Chem., 49(4) (2008) pp. 701-707.
The structure of Nb2Mo3O14 double oxide is refined from powder data using synchrotron radiation and the anomalous scattering effect; space group
P 421 m is found for the material. It is demonstrated that in the tetragonal unit cell with parameters a = 23.173 A,c = 4.0027 A Nb5+
and Mo6+ ions are stochastically distributed in MO6 octahedra and MO7 pentagonal bipyramids of the polygonal network structure of the Mo5O14 type.
GENESIS OF THE ACTIVE-COMPONENT PRECURSOR IN THE SYNTHESIS OF Pt/ Al2O3 CATALYSTS: I. TRANSFORMATION OF THE [PtCl6]2- COMPLEX IN THE INTERACTION BETWEEN CHLOROPLATINIC ACID AND THE γ-Al2O3 SURFACE
O.B. Bel’skaya*, R.Kh. Karymova*, D.I. Kochubey, V.K. Duplyakin*
(*Institute of Hydrocarbons Processing, Omsk, Russia)
Kinet. Catal., 49(5) (2008) pp. 729-736.
Gradient elution experiments have revealed the difference between platinum complexes in terms of the strength of their interaction with the alumina surface. A considerable part (30–40%) of the supported platinum is nondesorbable via competitive ion exchange reactions or upon changes in the charge state of the support surface. The surface platinum complexes can be divided into ion-exchangeable and coordinatively fixed species according to the nature of their bonding with aluminum oxide. Combining desorption and spectroscopic methods (EXAFS and diffuse reflectance spectroscopy) has made it possible to characterize the surface complexes. The strongest metal–support interaction takes place in the fixation of hydrolyzed platinum species.
INVESTIGATION OF POLYCRYSTALLINE COPPER(II) CHLORIDE–1.5DIMETHYLTETRAZOLE COMPLEX COMPOUND WITH X-RAY ABSORPTION SPECTROSCOPY
L.S. Ivashkevich*, A.Yu. Kuz’min**, D.I. Kochubey, V.V. Kriventsov, A.N. Shmakov, A.S. Lyakhov*, V.V. Efimov***, S.I. Tyutuynnikov***, O.A. Ivashkevich*
(*Research Institute of Physicochemical Problems, Belarussian State University, Minsk, Belarus; **Institute of Solid-State Physics of Latvia University, Riga, Latvia; ***Joint Institute for
Nuclear Research, Dubna, Russia)
J. Surf. Invest. X-Ray, Synchrotron Neutron Tech., 2(4) (2008) pp. 641–645.
The polycrystalline copper(II) chloride–1.5dimethyltetrazole (CuCl2L, where L is 1.5-dimethyltetrazole) complex compound is investigated with the methods of extended X-Ray absorption fine-structure (EXAFS) and X-Ray absorption near-edge structure (XANES) spectroscopy at the K absorption edge. The data on the complex structure are compared to the results of X-Ray diffraction study.
THE STRUCTURE STUDY OF AMORPHOUS NANOCRYSTALLINE NANOCOMPOSITE FILMS OF GERMANIUM BY AFM AND EXAFS METHODS
R.G. Valeev*, A.N. Deev*, D.V. Surnin*, V.V. Kriventsov, O.V. Karban*, V.M. Vetoshkin*, O.I. Pivovarova*
(*Physical-Technical Institute, Izhevsk, Russia)
Surf. Interface Anal., 40(3-4) (2008) pp. 547-551.
Nanocomposites based on nanocrystallites in amorphous matrix of semiconductor material involved increasing interest. Such structures allow not only to avoid charge transfer between separate quantum dots by means of spatial division of elements, but also to protect nanostructures from external influences. Moreover using of an amorphous matrix enables greatly raise a quantum yield of a luminescence of nanocomposites in case of their application in light-emitting devices as formation of “environment” of the amorphous semiconductor with the large width of the band gap around nanocrystalline core. It allows to avoid non-radiating recombination of excitons on a crystallite surface. One of the main aspects of technological application of materials on the basis of semiconductor nanocomposites, is their use as new generation of nanoelectronic devices (diodes, switches) because the phenomena occurring on the amorphous semiconductor – nanocrystalline semiconductor border has undressed in many respects are similar to effects of system metal-semiconductor.In the given work researches of structure of amorphously-nanocrystaline composite germanium films by methods of X-Ray Diffraction and EXAFS-spectroscopy are carried out. Films were obtained by a method of thermal evaporation of a material in ultrahigh vacuum. It is shown, that the nanocrystallites sizes in an amorphous matrix essentially vary depending on obtaining conditions (according to XRD-data), their percentage vary from 10 up to 90 % (according to EXAFS).
LOCAL ATOMIC STRUCTURE OF ZINC SELENIDE FILMS: EXAFS DATA
R.G. Valeev*,**, A.N. Deev*, F.Z. Gilmutdinov*, S.G. Bystrov*, O.I. Pivovarova*,**, E.A. Romanov**, V.V. Kriventsov, M.P. Sharafutdinov, A.A. Eliseev***
(*Physical-Technical Institute, Izhevsk, Russia; **Udmurtia State University, Izhevsk, Russia; ***Moscow Lomonosov State University, Moscow, Russia)
J. Struct. Chem., 49(Supplement) (2008) pp. 124-128.
This paper presents the results of the study of the structural state and local atomic structure of zinc selenide films obtained by thermal evaporation in supervacuum at condensation temperatures of −150°C, 0, and 150°C. Structure-sensitive methods such as X-ray diffraction, atomic force microscopy, and EXAFS spectroscopy were used. The parameters of the local atomic environment (interatomic distances, coordination numbers) of zinc and selenium atoms were obtained by Fourier transformation.
INFLUENCE OF THE NUCLEARITY OF COPPER(II) CHLORIDE COMPLEXES ON THEIR ACTIVITY IN CATALYTIC C-Cl BOND METATHESIS
E.N. Golubeva*, V.I. Pergushov*, A.I. Kokorin**, D.I. Kochubey, V.V. Kriventsov, N.A. Zubareva*
(*Moscow Lomonosov State University, Moscow, Russia; **Semenov Institute of Chemical Physics, Moscow, Russia)
Kinet. Catal., 49(5) (2008) pp. 737-742.
Catalytic systems containing mainly mononuclear (CuCl 42-) or dinuclear (Cu2Cl62-) tributylbenzylammonium chlorocuprates are prepared by adsorption on silicar surfaces of different structures (Aerosil and Silokhrom). Using ESR, XANES, and electronic spectroscopy, the CuCl 42- ions are shown to be reduced rapidly under conditions of C–Cl bond metathesis, whereas the dinuclear chlorocuprates are relatively stable. A correlation between the number of copper ions in the chlorocuprate anion and its catalytic activity is established: the mononuclear complexes are several times more active than their dinuclear counterparts.
NMR STUDIES OF INTERACTIONS IN SOLUTIONS DURING THE SYNTHESIS OF MoVTeNb OXIDE CATALYSTS
R.I. Maksimovskaya, V.M. Bondareva, G.I. Aleshina
Eur. J. Inorg. Chem., 11(31) (2008) pp. 4906-4914.
Aqueous solutions used for the synthesis of MoVTeNb oxide catalysts have been studied using125Te, 95Mo, 51V and 17O NMR. Polyoxometalate (POM) anion V9TeO285– (I) of the decavanadate structure, containing Te6+ in one of its two central positions, has been for the first time identified in VV-TeVI solutions. In ternary MoVI-VV-TeVI solutions, the following POMs were observed: TeMo6O246– (II) (pH ~7.8–2), previously unknown complexes of proposed compositions TeV3Mo3O249– (III) (pH ~ 8–5) and TeMo3V5O275– (IV) (pH ~ 6–1). In addition to the above complexes, VO2+ and MoO22+ oxalates form in the presence of oxalic acid. Upon adding niobium oxalate, Nb2O5 gel forms without any Nb containing species in solution.
PRACTICAL ASPECTS OF 51V AND 93Nb SOLID-STATE NMR SPECTROSCOPY AND APPLICATIONS TO OXIDE MATERIALS
O.B. Lapina, D.F. Khabibulin, A.A. Shubin, V.V. Terskikh
Progr. NMR Spectr., 53(3) (2008) pp. 128-191.
Advantages and restrictions of various solid-state NMR techniques as applied to vanadium and niobium are discussed with illustrations from a variety of vanadium and niobium containing oxide materials, including individual highly-crystalline compounds, solid solutions, glasses and catalysts. The main purpose of this work is to provide readers with the latest comprehensive compilation of 51V and 93Nb NMR data in oxide materials, and to demonstrate the great potential of 51V and 93Nb NMR in solid-state chemistry.
RADIATION-CHEMICAL SYNTHESIS OF PHOSPHORUS- AND SULFUR-CONTAINING POLYMERS
N.P. Tarasova*, Yu.V. Smetannikov*, A.N. Lupanov*, L.N. Gal’**, O.B. Lapina, D.F. Khabibulin
(*Mendeleev University of Chemical Technology, Moscow, Russia; **St. Petersburg State Polytechnical University, St. Petersburg, Russia)
Theor. Found. Chem. Eng., 42(5) (2008) pp. 657-661.
Phosphorus- and sulfur-containing polymers were obtained by radiation-chemical synthesis from elementary phosphorus and sulfur in benzene. The structure and composition of the products were studied by solid-phase 31P NMR spectroscopy, MALDI mass spectroscopy, and other physicochemical analytical methods. The reactivity ratios of inorganic monomers, phosphorus and sulfur, were determined.
STRUCTURAL AND REACTIVE RELEVANCE OF V+Nb COVERAGE ON ALUMINA OF V–Nb–O/Al2O3 CATALYTIC SYSTEMS
A.E. Lewandowska*,**, M.A. Banares*, M. Ziolek**, D.F. Khabibulin, O.B. Lapina
(*Instituto de Catdlisis y Petroleoquimica, CSIC, Madrid, Espagne; **A. Mickiewicz University, Faculty of Chemistry, Poznan, Poland)
J. Catal., 255(1) (2008) pp. 94-103.
Vanadium and niobium species (together and separately) were loaded onγ-alumina, and the resulting catalysts were run in the methanol conversion. This reaction was studied by both GC analysis and FTIR study in the flow system. The catalytic properties are discussed based on the combined FTIR and 27Al, 51V and 1H MAS NMR studies. The NMR studies revealed a different mechanism of interaction between Nb and Al2O3 than that between V and Al2O3. This predetermines the structure of vanadium sites in bimetallic VNb/Al samples. The effect of coverage was considered for various metal loadings ranging from below to above monolayer. One of the most interesting findings is that the surface Nb oxide species exhibited a redox character below monolayer but were acidic above monolayer. 27Al MAS NMR revealed a strong alumina-Nb interaction that may account for its redox performance. Moreover, the role of sulfate from vanadium precursor is evidenced.
129Xe NMR SPECTROSCOPY OF ADSORBED XENON: POSSIBILITES FOR EXPLORATION OF MICROPOROUS CARBON MATERIALS
A.V. Romanenko, O.B. Lapina, X. Py*, J. Fraissard**
(*CNRS-PROMES, Rambla de la Thermodynamique, Perpignan Cedex, France; **Laboratoire de Physique Quantique, Ecole Superieure de Physique et de Chimie Industrielles, Paris, France)
Russ. J. General Chem., 78(11) (2008) pp. 2171-2181.
Despite the extensive use of 129Xe NMR for characterization of high surface-to-volume porous solids, particularly zeolites, this method has not been widely used to explore the properties of microporous carbon materials. In this study, commercial amorphous carbons of different origin (produced from different precursors) and a series of activated carbons obtained by successive cyclic air oxidation/pyrolysis treatments of a single precursor were examined. Models of 129Xe chemical shift as a function of local Xe density, mean pore size, and temperature are discussed. The virial coefficient arising from binary xenon collisions,δXe–Xe, varied linearly with the mean pore size given by N2 adsorption analysis;δXe–Xe appeared to be a better probe of the mean pore size than the chemical shift extrapolated to zero pressure,δS.
MULTINUCLEAR MRI OF SOLIDS: FROM STRUCTURE TO TRANSPORT
I.V. Koptyug*, A.V. Khomichev*, A.A. Lysova, R.Z. Sagdeev*
(*International Tomography Center, Novosibirsk, Russia)
Appl. Magn. Reson., 32(3) (2007) pp. 1-11.
Direct multinuclear imaging of rigid solids has been performed using the conventional two-pulse spin-echo pulse sequence and liquids magnetic resonance imaging (MRI) hardware. Two-dimensional 27Al and 51V images of an Al2O3-V2O5-glass composite sample and 11B, 23Na, 27Al and 29Si images of glass have been detected, extending the range of nuclei and solid materials that can be studied by this approach. For a spinning cylinder packed with Al2O3 powder, quantitative velocity maps have been obtained by directly detecting the 27Al nuclear magnetic resonance signal of the solid phase. The two velocity components in the imaging plane transverse to the rotation axis have been mapped using the three-pulse stimulated echo sequence. Some possibilities to improve sensitivity in the MRI experiments on rigid solids have been considered. In particular, inversion of the satellite transitions by a double frequency sweep adiabatic passage has led to a signal enhancement by a factor of two in 27Al MRI of a glass sample despite a short repetition time (0.5 s) of the imaging pulse sequence.
MONITORING TRANSPORT PHENOMENA OF PARAMAGNETIC METAL-ION COMPLEXES INSIDE CATALYST BODIES WITH MAGNETIC RESONANCE IMAGING: TUNING THE COBALT DISTRIBUTION FROM EGG-SHELL OVER EGG-WHITE AND EGG-YOLK TO UNIFORM BY THE ADDITION OF CITRATE
J.A. Bergwerff*, A.A. Lysova, L. Espinosa Alonso*, I.V. Koptyug**, B.M. Weckhuysen*
(*Inorganic Chemistry and Catalysis Group, Utrecht University, Utrecht, The Netherlands; **International Tomography Center, Novosibirsk, Russia)
Chem. Eur. J., 14 (2008) pp. 2363-2374.
An indirect magnetic resonance imaging (MRI) method has been developed to determine in a noninvasive manner the distribution of paramagnetic Co2+ complexes inside Co/ Al2O3 catalyst extrudates after impregnation with Co2+/citrate solutions of different pH and citrate concentrations. UV/Vis/NIR microspectroscopic measurements were carried out simultaneously to obtain complementary information on the nature of the Co2+ complexes. In this way, it could be confirmed that the actual distribution of Co2+ inside the extrudates could be derived from the MRI images. By combining these space- and time-resolved techniques, information was obtained on both the strength and the mode of interaction between [Co(H2O)6]2+ and different Co2+ citrate complexes with the Al2O3 support. Complexation of Co2+ by citrate was found to lead to a stronger interaction of Co with the support surface and formation of an eggshell distribution of Co2+ complexes after impregnation. By addition of free citrate and by changing the pH of the impregnation solution, it was possible to obtain the rather uncommon egg-yolk and egg-white distributions of Co2+ inside the extrudates after impregnation. In other words, by carefully altering the chemical composition and pH of the impregnation solution, the macrodistribution of Co2+ complexes inside catalyst extrudates could be fine-tuned from eggshell over egg white and egg yolk to uniform.
BIOPOLYMER AND WATER DYNAMICS IN MICROBIAL BIOFILM EXTRACELLULAR POLYMER SUBSTANCE
J.A. Hornemann*, A.A. Lysova, S.L. Codd*, J.D. Seymour*, S.C. Busse*, P.S. Steward*, J.R. Brown*
(*Montana State University, Bozeman, MT)
Biomacromol., 9(9) (2008) pp. 2322-2328.
Nuclear magnetic resonance (NMR) is a noninvasive and nondestructive tool able to access several observable quantities in biofilms such as chemical composition, diffusion, and macroscale structure and transport. Pulsed gradient spin echo (PGSE) NMR techniques were used to measure spectrally resolved biomacromolecular diffusion in biofilm biomass, extending previous research on spectrally resolved diffusion in biofilms. The dominant free water signal was nulled using an inversion recovery modification of the traditional PGSE technique in which the signal from free water is minimized in order to view the spectra of components such as the rotationally mobile carbohydrates, DNA, and proteins. Diffusion data for the major constituents obtained from each of these spectral peaks demonstrate that the biomass of the biofilm contains both a fast and slow diffusion component. The dependence of diffusion on antimicrobial and environmental challenges suggests the polymer molecular dynamics measured by NMR are a sensitive indicator of biofilm function.
THE FIRST (31P, 17O, AND 103Rh) NMR OBSERVATION COMPLEX FORMATION OF RHODIUM(III) WITH PHOSPHORIC ACID
M.A. Fedotov, A.V. Belyaev*
(*Nikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia)
Russ. J. Inorg. Chem., 53(5) (2008) pp. 761-764.
31
P, 17O, and 103Rh NMR spectroscopy shows that rhodium(III) reacts with phosphoric acid to generate polynuclear aquaphosphate complexes in which phosphate ions mostly have a bridging function. Assignment of 103Rh NMR signals in dominant rhodium complexes is suggested.THE STATE OF Al(III) IN ALCOHOL SOLUTIONS OF ALUMINUM ALKOXIDE AS PROBED BY 27Al AND 13C NMR AND SMALL-ANGLE X-RAY SCATTERING
M.A. Fedotov, V.V. Molchanov, R.N. Zotov, F.V. Tuzikov
Russ. J. Inorg. Chem., 53(10) (2008) pp. 1621-1627.
Solutions of aluminum alkoxides obtained by interaction of aluminum metal with methyl, ethyl, and isopropyl alcohols were studied by 27Al and 13C NMR and small-angle X-ray scattering. Alkoxides with a tetrahedral environment of aluminum prevail in methanol solutions, and those with an octahedral environment of aluminum predominate in ethanol solutions. In isopropyl alcohol at 293 K, polynuclear alkoxides with tetrahedral, octahedral, and pentacoordinated aluminum environments coexist. The structure of polynuclear complexes was refined by comparison of their calculated dimensions with small-angle X-ray scattering data.
EFFECT OF TEMPERATURE ON THE STRUCTURAL CHARACTERISTICS OF ZIRCONIUM DIOXIDE NANOPARTICLES PRODUCED UNDER CONDITIONS OF MICROWAVE TREATMENT
P.E. Strizhak*, A.I. Tripol’sky*, T.N. Gurnik*, F.V. Tuzikov, E.M. Moroz, T.E. Konstantinova**, N.A. Tuzikova, V.P. Kolko, I.A. Danilenko**, O.A. Gorban**
(*Pisarzhevskii Institute of Physical Chemistry, Kyiv, Ukraine; **Galkin Donets’k Physicotechnical Institute, Donets’k, Ukraine)
Theor. Exp. Chem., 44(3) (2008) pp. 144-149.
The effect of the sintering temperature on the structural characteristics of nanosized zirconium dioxide particles treated by microwave radiation during the drying process was investigated by small-angle X-ray scattering and the BET method. It was shown that the specific surface area, particle size, polydispersivity index, and surface and mass fractal dimensionality of zirconium dioxide depend on its heat treatment conditions.
A STUDY OF SOLID-STATE RHODIUM(III) SULFATES
S.N. Shagabutdinova*, M.A. Fedotov, A.V. Belyaev*, V.D. Il’yashevich**, E.I. Pavlova**
(*Nikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia; **JSC Krastsvetmet, Krasnoyarsk, Russia)
Russ. J. Coord. Chem., 34(12) (2008) pp. 917-923.
Solid-state rhodium(III) sulfates and their aqueous solutions were examined by IR and electronic absorption spectroscopy, thermogravimetry, X-ray powder diffraction analysis, and 103Rh and 17O NMR spectroscopy. A study of the spontaneous aquation of freshly prepared solutions showed that this process results in an equilibrium between the subsystems of monomeric and oligomeric complexes. It was found that solid-state rhodium(III) sulfates vary in phase composition, basically consisting of dimeric and trimeric complexes.
WATER DYNAMICS IN BULK AND DISPERSED IN SILICA CaCl2 HYDRATES STUDIED BY 2H NMR
D.I. Kolokolov, I.S. Glaznev, Yu.I. Aristov, A.G. Stepanov, H. Jobic* (*Institut de Recherches sur la Catalyse, CNRS, France)
J. Phys. Chem. C, 112(33) (2008) pp. 12853-12860.
The mobility of water in deuterated analogues of CaCl2xnH2O (n = 2, 4, 6) hydrates has been studied by solid-state2H NMR spectroscopy. The dynamics of water molecules in the hydrates dispersed in the mesopores of silica are compared with the bulk state. Analysis of the 2H NMR line shape and T1 and T2 relaxation times allowed to characterize the dynamics of water in a wide temperature range (120-493 K). In both crystalline and melted hydrates, the mobility of water molecules is governed by O-D...Cl hydrogen bonding. Both the bulk and dispersed hydrates have been found to exhibit three types of molecular motion. Two of them represent fast internal and local motions performed on a time scale of 10-10-10-11 s. The third slow isotropic reorientation occurs on a time of 10-610-7 s. The dispersed hydrates become involved in the slow isotropic motion at a temperature 50-130 K lower than the corresponding bulk hydrates. The temperature TNMR at which the dispersed hydrates is involved in isotropic motion represents the melting point of the hydrates located in the silica pores. The decrease of the melting point for the dispersed hydrates is in a good accordance with Gibbs-Thompson effect for dispersed materials. In the dispersed hydrates, the water molecules reorient isotropically one order of magnitude faster in the temperature range 230-490 K, that is water is more mobile in the dispersed hydrates. The slow isotropic reorientation of water molecules is influenced by both the quantity of water in the hydrate and the dispersibility of the hydrates. In the case of the hydrate with n = 4, the activation energy of this motion decreases by ca. 3 times when the hydrate becomes dispersed in the silica pores.
1H NMR SIGNAL BROADENING IN SPECTRA OF ALKANE MOLECULES ADSORBED ON MFI-TYPE ZEOLITES
E.E. Romanova*, C.B. Krause*, A.G. Stepanov, U. Wilczok**, W. Schmidt**, J.M. van Baten***, R. Krishna***, A. Pampel****, J. Kaerger*, D. Freude*
(*Universitat Leipzig, Leipzig, Germany; **Max-Planck-Institut fur Kohlenforschung, Mulheim, Germany; ***University of Amsterdam, Amsterdam, The Netherlands; ****Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany)
Solid State NMR, 33(4) (2008) pp. 65-71.
The anisotropic behavior of C1–C6 alkane molecules adsorbed in MFI zeolite was studied by1H nuclear magnetic resonance (NMR) using single-pulse excitation, Carr–Purcell–Meiboom–Gill (CPMG) pulse sequence, Hahn echo (HE) pulse sequence, and magic-angle spinning. The molecular order parameter was obtained by both static 2H NMR spectroscopy and molecular simulations. This yields an order parameter in the range of 0.28–0.42 for linear alkanes in MFI zeolite, whereas the parameter equals zero for FAU zeolite with a cubic symmetry. Thus, in the case of a zeolite with a non-cubic symmetry like MFI, the mobility of the molecules in one crystallite cannot fully average the dipolar interaction. As a consequence, transverse nuclear magnetization as revealed in the echo attenuation notably deviates from a mono-exponential decay. This information is of particular relevance for the performance of pulsed field gradient (PFG) NMR diffusion experiments, since the occurrence of non-exponential magnetization attenuation could be taken as an indication of the existence of different molecules or of molecules in different states of mobility.
OBSERVATION OF PARAHYDROGENINDUCED POLARIZATION IN HETEROGENEOUS HYDROGENATION ON SUPPORTED METAL CATALYSTS
K.V. Kovtunov*, I.E. Beck, V.I. Bukhtiyarov, I.V. Koptyug*
(*International Tomography Center, Novosibirsk, Russia)
Angew. Chem. Int. Ed., 47(8) (2008) pp. 1492–1495.
It was demonstrated for the first time that heterogeneous hydrogenation of an alkene (propylene) with supported metal catalysts (Pt/ Al2O3, Pd/ Al2O3) leads to an observation of enhanced signals in the 1H NMR spectra of the reaction product (propane) when hydrogen enriched in the para-H2 spin isomer is used in the reaction. This observation indicates that hydrogen addition occurs pairwise to a measurable extent.
TEMPERATURE EFFECTS ON THE IR SPECTRA OF CRYSTALLINE AMINO ACIDS, DIPEPTIDES, AND POLYAMINO ACIDS: II. L-AND DL-SERINES
Yu.A. Chesalov, G.B. Chernobai*,**, E.V. Boldyreva*,**
(*Novosibirsk State University, Novosibirsk, Russia; **Institute of Solid State Chemistry and Mechanochemistry, Novosibirsk, Russia)
J. Struct. Chem., 49(4) (2008) pp. 627-638.
The IR spectra of L-and DL-serines H3+-CH(CH2OH)-COO− (without diluents) were investigated in the temperature range 93–413 K; the changes in the IR spectra due to temperature variations were correlated with previously obtained diffraction data on anisotropic compression of structure and changes in the geometrical parameters of the hydrogen bonds.
STUDY OF THE TEMPERATURE EFFECT ON IR SPECTRA OF CRYSTALLINE AMINO ACIDS, DIPEPTIDS, AND POLYAMINO ACIDS: III.α-GLYCYLGLYCINE
Yu.A. Chesalov, G.B. Chernobai*,**, E.V. Boldyreva*,**
(*Novosibirsk State University, Novosibirsk, Russia; **Institute of Solid State Chemistry and Mechanochemistry, Novosibirsk, Russia)
J. Strut. Chem., 49(6) (2008) pp. 1012-1021.
The IR spectra of α-glycylglycine (H3+N-CH2-CO-NH-CH2-COO−) are studied in the temperature range of 93 to 413 K. Changes in the spectra due to temperature variation are correlated with the previously obtained X-ray diffraction data on anisotropic compression of the structure and changes in the parameters of hydrogen bonding. Changes in the vibrational frequencies of NH3+ and COO groups in the IR spectrum of α-glycylglycine are compared to changes in the vibrational frequencies of the same groups in the IR spectra of polymorphs of glycine, L- and DL-serine.
STUDY OF THE TEMPERATURE EFFECT ON IR SPECTRA OF CRYSTALLINE AMINO ACIDS, DIPEPTIDES, AND POLYAMINO ACIDS: IV. L-CYSTEINE AND DL-CYSTEINE
V.S. Min’kov*,**, Yu.A. Chesalov, E.V. Boldyreva*,**
(*Novosibirsk State University, Novosibirsk, Russia; **Institute of Solid State Chemistry and Mechanochemistry, Novosibirsk, Russia)
J. Struct. Chem., 49(6) (2008) pp. 1022-1034.
A study of the IR spectra of L-and DL-cysteine is carried out in a range of frequencies from 4000 cm−1 to 600 cm−1 and temperatures from 333 K to 83 K. Changes in the spectra of L- and DL-cysteine (NH3+CH(CH2SH)-COO−) on cooling are analyzed in comparison with the spectra of L- and DL-serine (NH3+CH(CH2OH)-COO−) and three polymorphs of glycine (NH3+CH2-COO−) previously studied under temperature variation. Changes in the IR spectra at variable temperatures are correlated with previously obtained diffraction data on anisotropic compression of the structure and changes in the geometric parameters of hydrogen bonds. Special attention is paid to temperature regions in which anomalies were detected by vibrational spectroscopy, X-ray diffraction, and calorimetry.
FT-IR AND FT-RAMAN SPECTRA OF FIVE POLYMORPHS OF CHLORPROPAMIDE. EXPERIMENTAL STUDY AND ab initio CALCULATIONS
Yu.A. Chesalov, V.P. Baltakhinov, T.N. Drebushchak*, E.V. Boldyreva*, N.V. Chukanov**, V.A. Drebushchak***
(*Institute of Solid State Chemistry, Novosibirsk, Russia; **Novosibirsk Institute of Organic Chemistry, Novosibirsk, Russia; ***Institute of Geology and Mineralogy, Novosibirsk, Russia)
J. Mol. Struct., 891(1-3) (2008) pp. 75-86.
IR- and Raman spectra were studied for five polymorphs of chlorpropamide (α, β, γ, δ and ε) (phase purity proved by DSC, X-ray single-crystal and powder diffraction). The equilibrium geometry and the vibrational spectra for different molecular conformations were calculated ab initio (DFT, B3LYP approximation). The assignment of the vibrational bands was made on the basis of the theoretical calculations and a comparison of the experimentally measured spectra for the crystalline polymorphs and the melt. The differences in the experimental vibrational spectra of the five chlorpropamide polymorphs were correlated with the X-ray structural data, and shown to be mainly due to the intermolecular interactions effect, and only to a smaller extent – to the conformational changes.
PHOTOCATALYTIC OXIDATION OF TABUN SIMULANT-DIETHYL CYANOPHOSPHATE: FTIR IN SITU INVESTIGATION
P.A. Kolinko, D.V. Kozlov
Environ. Sci. Technol., 42(12) (2008) pp. 4350-4355.
Gas phase photocatalytic oxidation of diethyl cyanophosphate vapor in a static reactor using TiO2 and modified TiO2 as the photocatalyst was studied with the FTIR in situ method. The transition metals Pt, Au, and Ag were used for TiO2 modification by the chemical and photochemical deposition methods as well as the mechanical mixture of TiO2 with manganese oxide to improve its adsorption and catalytic activity. Photocatalytic oxidation of diethyl cyanophosphate in a static reactor results in its complete mineralization with carbon dioxide, phosphoric and nitric acids, and water as the major final products. HCN was demonstrated to be the only toxic gaseous intermediate of diethyl cyanophosphate photocatalytic oxidation, formed as a result of diethyl cyanophosphate hydrolysis. Diethylphosphate and acetic and formic acids were registered as the surface intermediates. It was found that cyanhydric acid is oxidized slowly with the use of unmodified TiO2. The formation of surface cyanide complexes with Ag and Au ions could be responsible for the fast removal of HCN from the gas phase and its further photooxidation in the case of using TiO2 with deposited Au and Ag.
ISOPROPANOL DIFFUSION AND DEHYDRATION IN ZEOLITE HZSM-5. SPECTROKINETIC STUDY
T.S. Glazneva, V.P. Shmachkova, E.A. Paukshtis
React. Kinet. Catal. Lett., 94(1) (2008) pp. 11-20.
The isopropanol diffusion and dehydration in zeolite HZSM-5 were studied by FTIR spectroscopy. The alcohol dehydration was shown to start at the temperature above 60°C. It was found that at temperatures above 350°C, the isopropanol dehydration was limited by diffusion in the mesopores of zeolite. The method developed allows studying the kinetics of interactions of the reagent molecules with the OH-groups at the external surface of the zeolite and inside its channels.
BRONSTED ACIDITY OF GLASS FIBER MATERIALS
T.S. Glazneva, E.A. Paukshtis
Chem. Sustain. Devel., 16(4) (2008) pp. 473-478.
The results of investigation of acid properties of glass fiber materials by IR spectroscopy using the adsorption of ammonia, H/D exchange and isopropanol dehydration, are given. It is shown that the catalysts contain a large amount of Bronsted acid sites (BAS) with the strength comparable with that of BAS of zeolite HZSM-5. Number of BAS is proportional to Al content in the glass fiber. It is revealed that BAS are located in the bulk of the glass fiber. The centers located at up to 100 nm depth of a glass fiber are accessible for the reagent molecules of isopropanol.
SURFACE ACIDITY AND BASICITY OF OXIDE CATALYSTS: FROM AQUEOUS SUSPENSIONS TO IN SITU MEASUREMENTS
T.S. Glazneva, N.S. Kotsarenko, E.A. Paukshtis
Kinet. Catal.,
49(6) (2008) pp. 859–867.
The review covers the achievements of recent decades in the investigation of the acid–base properties of oxide catalyst surfaces. Both conventional and new investigation techniques are reviewed, including SSITKA for H/D exchange.
REVERSIBLE MODIFICATION OF MAGNETIC PROPERTIES OF Fe3C NANOPARTICLES BY CHEMISORPTION OF CO
N.A. Ivanova*, A.A. Onischuk*, S.V. Vosel*,**, P.A. Purtov*,***, N.T. Vasenin, V.F. Anufrienko, V.N. Ikorski****
(*Institute of Chemical Kinetics and Combustion, Novosibirsk, Russia; **Institute of Geology and Mineralogy, Novosibirsk, Russia; ***Novosibirsk State University, Novosibirsk, Russia; ****International Tomography Center, Novosibirsk, Russia)
Appl. Magn. Reson., 33(3) (2008) pp. 285-291.
The paper is devoted to the electron spin resonance and magnetic measurements of Fe3C nanoparticles covered by a carbon structure. There is a reversible modification of the magnetic properties by the chemisorption of CO and O2. The CO chemisorption results in the transition of the majority of the Fe3C nanoparticles from the ferromagnetic to the superparamagnetic state. The O2 chemisorption results in the backward transition.
FORMATION OF DISPERSE FERROMAGNETIC NANOPARTICLES IN ZEOLITES IN THE COURSE OF THERMAL ACTIVATION IN OXYGEN
O.N. Martyanov, V.F. Yudanov
J. Struct. Chem., 49(3) (2008) pp. 421-426.
Samples of synthetic high-silica zeolites after high-temperature activation in oxygen are studied by ferromagnetic resonance. Observation of the fine structure of ferromagnetic resonance (FMR FS) indicates the formation of magnetic iron oxide nanoparticles in the course of thermal treatment of zeolites in oxygen. Features of the formation of a dispersed ferromagnetic phase in zeolites, geometric and magnetic characteristics of constituent nanoparticles are discussed.
STEPWISE MAGNETIZATION OF DISPERSED FERROMAGNETS DUE TO MAGNETIC INTERPARTICLE INTERACTIONS
S.N. Trukhan, O.N. Martyanov, V.F. Yudanov
Phys. Solid State, 50(3) (2008) pp. 456-462.
The main features of stepwise magnetization of dispersed ferromagnets caused by magnetic interparticle interactions are studied using a two-particle model. The ranges of values of the magnetic anisotropy constants of particles and of the dipole– dipole interaction between them are determined over which a reproducible jumpwise change in the magnetization of the system occurs in an external positive magnetic field. The proposed model is shown to explain the main specific features of the fine structure of the ferromagnetic resonance spectra.
FMR FINE STRUCTURE OF DISPERSED MAGNETS. PHYSICAL ORIGIN AND APPLICATIONS
O.N. Martyanov, S.N. Trukhan, V.F. Yudanov
Appl. Magnet. Resonance, 33 (2008) pp. 57-71.
An original approach is proposed to study the dipole-dipole interparticle interactions in dispersed magnets. This is the registration and analysis of the noise-like ferromagnetic resonance fine structure (FMR FS), which is caused by the magnetic dipole-dipole interaction between magnetic domains. The peculiarities of fine structure formation are discussed. The experimental examples of the possible FS method applications are summarized.
INFLUENCE OF Pd CODEPOSITION ON THE MAGNETIC PROPERTIES OF Co PARTICLES ON ALUMINA/NiAl(110)
O.N. Martyanov, T. Risse*, H.-J. Freund*
(*Fritz-Haber-Institut der Max-Planck Gesellschaft, Berlin, Germany)
J. Phys. Chem. B, 129(11) (2008) pp. 104705-104712.
Changes of the magnetic properties of ferromagnetic Co particles deposited at room temperature on a thin alumina film grown on a NiAl(110) substrate were investigated as a function of Pd coverage by subsequent deposition of Pd onto deposited Co particles. From previous X-ray photoelectron spectroscopy, IR, and temperature programmed desorption experiments it was concluded that Pd forms a shell on top of Co particles. However, the current experiments indicate that Pd does induce structural rearrangements within the Co particles which may also involve the intermixing of small amounts of Pd into the Co particles. The latter is inferred from a change in the -value for small particles. The impact of a larger intermixture of Co and Pd on the magnetic properties will be emphasized by a reversed deposition order where Pd particles were deposited first and subsequently covered by Co. The reversal of the deposition order increases the magnetic anisotropy of the particles considerably.
PREPARATION, MICROSTRUCTURE, MAGNETIC AND TRANSPORT PROPERTIES OF BULK TEXTURED Bi1.8Pb0.3Sr1.9Ca2Cu3Ox AND Bi1.8Pb0.3Sr1.9Ca2Cu3Ox +Ag CERAMICS
M.I. Petrov*, I.L. Belozerova**, K.A. Shaikhutdinov*, D.A. Balaev*, A.A. Dubrovskii*, S.I. Popkov*, A.D. Vasiliev*, O.N. Martyanov
(*Kirensky Institute of Physics, Krasnoyarsk, Russia; **Reshetnev Siberian State Aerospace University, Krasnoyarsk, Russia)
Supercond. Sci. Technol., 21(10) (2008) 105019.
A new method of preparation of bulk textured Bi2223 ceramics and Bi2223+Ag composites, based on room temperature pressing of foamed precursor (Bi2223, Bi2223+Ag) in a liquid medium, is proposed. SEM and XRD data prove a high degree of texture of the bulk samples obtained. Magnetic measurements performed in directions H || C–axis and H || a-b-planes of Bi2223 crystallites demonstrates anisotropy of magnetization confirming the texture of the ceramics. The materials obtained possess large diamagnetic response in the direction H || a-b-planes of Bi2223 crystallites at both 77.4 and 4.2 K.
FORMATION OF HOLLOW SPHERES UPON OXIDATION OF SUPPORTED COBALT NANOPARTICLES
P.A. Chernavskii*, G.V. Pankina*, V.I. Zaikovsky, N.V. Peskov*, P. Afanasiev**
(*Moscow Lomonosov State University, Moscow, Russia; **Institut de Recherche sur la Catalyse et Environnement, Villeurbanne, Cedex, France)
J. Phys. Chem. C, 112(26) (2008) pp. 9573-9578.
Oxidation of cobalt nanoparticles supported on montmorillonite was studied using transmission electron microscopy and temperature programmed reduction of the oxide particles. It has been shown that hollow shells of cobalt oxide were formed in this process, consisting of the mixture of CoO and Co3O4 oxides. A linear relationship between the thickness of shells and the initial particles size was established which suggests that both diffusion of cobalt ions through the oxide layer and diffusion of the oxygen into cobalt occur, but particles sintering is negligible compared with the reverse diffusion of cobalt. The lower critical diameter of cobalt particles was estimated, above which formation of hollow shells occurred. The hollow shells formation is suggested to be the reason for cobalt redispersion upon oxidation−reduction cycling of supported heterogeneous catalysts.
FORMATION OF SPHERICAL VOIDS IN THE OXIDATION OF Co NANOPARTICLES
P.A. Chernavskii*, G.V. Pankina*, V.I. Zaikovsky, N.V. Peskov*, V.V. Lunin*
(*Moscow Lomonosov State University, Moscow, Russia)
Russ. J. Phys. Chem. A, 82(4) (2008) pp. 690-693.
A high-resolution transmission microscopy study showed that the oxidation of Co nanoparticles deposited on montmorillonite resulted in the formation of nanoshells consisting of cobalt oxides and containing spherical voids. A linear dependence was found between the initial diameter of Co particles and the oxide shell thickness.
FORMATION OF MAGNETIC NANOCRYSTALS IN GERMANATE GLASSES DOPED WITH Fe AND Dy
I.S. Edel’man*, O.S. Ivanova*,**, V.N. Zabluda*, R.D. Ivantsov*, G.V. Bondarenko*, V.I. Zaikovsky, S.A. Stepanov***
(*Kirensky Institute of Physics, Krasnoyarsk, Russia; ** Siberian Federal University, Krasnoyarsk, Russia; ***Vavilov State Optical Institute, All-Russia Research Center, St. Petersburg, Russia)
Nanotech. Russ., 3(11-12) (2008) pp. 722-728.
Magnetic nanocomposites were synthesized from germanate glasses doped with iron and dysprosium oxides at low concentrations. The formation of nanoparticles (~5–20 nm in size) in glasses subjected to heat treatment under different conditions was observed using high-resolution electron microscopy. Nanoparticles had a well-resolved crystal structure. X-ray fluorescence microprobe analysis showed that iron and dysprosium are concentrated in particles. The examination of the field dependences of the magneto-optical effect revealed magnetic ordering in particles. A comparison of the interplanar distances obtained using electron microdiffraction with those of the known iron oxide compounds did not lead to unambiguous results. Almost all specific features in the magnetic circular dichroism spectra of the glasses corresponded to the features previously observed in the spectra of garnet ferrites. On this basis, it was assumed that the particles formed in the germanate glasses have a distorted garnet structure.
STABILIZATION OF COPPER NANOPARTICLES IN Cu-ZSM-5
S.A.Yashnik, V.F. Anufrienko, V.I. Zaikovsky, V.A. Rogov, S.Ph. Ruzankin, Z.R. Ismagilov
Stud. Surf. Sci. Catal., 174A (2008) pp. 177-180.
The copper nanoparticles formed during reduction of Cu-ZSM-5 in hydrogen at temperature 150 – 400oC were studied by UV-Vis spectroscopy and HRTEM. The plasmon resonance (PR) absorption at 1600017500 cm-1 was used for copper nanoparticles identification. It was shown that the chain-like and square-plain copper-oxide clusters stabilized in Cu-ZSM-5 during its preparation are the precursors of copper nanoparticles 2-10 nm.
FORMATION AND EVOLUTION OF MAGNETIC NANOPARTICLES IN BORATE GLASS SIMULTANEOUSLY DOPED WITH Fe AND Mn OXIDES
J. Kliava*, I. Edelman**, O. Ivanova**, R. Ivantsov**, O. Bayukov**, E. Petrakovskaja**, V.I. Zaikovsky, I. Bruckental***, Y. Yeshurun***, S. Stepanov****
(*CPMOH, Universite Bordeaux, Talence Cedex, France; **Kirensky Institute of Physics, Krasnoyarsk, Russia; ***Department of Physics, Bar-Ilan University, Ramat-Gan, Israel; ****Vavilov State Optical Institute, St. Petersburg, Russia)
J. Appl. Phys., 104(10) (2008) 103917 (11 pp.).
Evolution of the phase state of paramagnetic additions at various stages of synthesis and subsequent thermal treatment of glasses of the system Al2O3– K2O–B2O3 simultaneously doped with Fe2O3 and MnO is studied by means of a combination of experimental techniques: Faraday rotation (FR), electron magnetic resonance (EMR), transmission electron microscopy (TEM), Mossbauer spectroscopy, and magnetic measurements. Both FR and EMR show that magnetically ordered clusters occur already at the first stage of the glass preparation. In particular, for the ratio of the Fe andMn oxides in the charge close to 3:2, fine magnetic nanoparticles are formed with characteristics similar to those of manganese ferrite. By computer simulating the EMR spectra at variable temperatures, a superparamagnetic nature of these nanoparticles is confirmed and their mean diameter is estimated as approximately 3.2 nm. In the thermally treated glasses larger magnetic nanoparticles are formed, giving rise to FR spectra, characteristic of magnetically ordered systems, and the EMR spectra different from those in as-prepared glasses but also showing superparamagnetic narrowing. The Mossbauer spectroscopy corroborates the manganese ferrite structure of the nanoparticles and indicates their coexistence in the ferrimagnetic and superparamagnetic states. The TEM shows the presence of polydisperse nanoparticles on the background of the glass matrix, and electron diffraction of a selected region containing larger particles indicates a crystal structure close to that of MnFe2O4. Energy-dispersive atomic X-ray spectra confirm that the major part of Fe and Mn introduced to the glass composition is gathered in the particles, with the concentration ratio close to 2:1, characteristic of bulk MnFe2O4. Magnetic hysteresis loops of samples subjected to an additional thermal treatment demonstrate a strong increase in the coercive force, remnant magnetization, and high-field magnetic susceptibility with temperature decrease. The consistent results obtained using various techniques demonstrate that the formation of nanoparticles with characteristics close to those of MnFe2O4 confers to these glasses magnetic and magneto-optical properties typical of substances possessing magnetic order.
STRUCTURE OF HETEROGENEOUS STATES IN NANOCRYSTALLINE CoPd FILMS
E.M. Artem’ev*, V.I. Zaikovsky
(*Krasnoyarsk State University, Krasnoyarsk, Russia)
Bull. Russ. Academy Sci.: Phys., 72(10) (2008) pp. 1330-1332.
Thin films of equiatomic alloy CoPd have been produced by condensation at high substrate temperatures. The films obtained are characterized by microdiffraction patterns in the form of diffuse halo in the initial state. This is polymorphic martensitic transient state, formed during martensitic transformation of the low-temperature hcp phase to the high-temperature fcc phase. The metastable crystal structures arising in these alloy films are identified.
STRUCTURE OF GLASS SURFACES TREATED WITH THE NEW GLASS FROSTING PASTE SURFACE
O.N. Sidelnikova*, A.N. Salanov
(*Institute of Solid State Chemistry and Mechanochemistry, Novosibirsk, Russia)
Glass Technol., A, 49(4) (2008) pp. 179-182.
The paper is concerned with an investigation using scanning electron microscopy (SEM) of morphologies of frosted glass surfaces produced by using a new frosting paste. The new paste produces its effect by the physical process of surface ionic exchange and does not contain hydrofluoric acid or its compounds. The frosting process occurs at a temperature similar to 300oC and is characterized by the appearance of a system of microblocks (similar to 50-150μm in size) and microcracks (similar to 100-200 nm wide) at the glass surface. The microblock boundaries are essentially smooth and the front surfaces of the blocks are smooth. The surface morphology after the metal deposition on frosted glass carried out by chemical reduction in solution is also demonstrated. In particular, silver deposition was carried out by the chemical reduction of Ag+ to metallic Ag using a silvering solution based on ammoniac silver complexes in the presence of glucose as a reducing agent. Micrographs of the surface structures obtained with chemical etching and Sand blasting are compared in this paper with those of the structures formed diving frosting by the new frosting paste. This comparison indicates that the glass surface morphology after glass frosting with the new glass frosting paste differs substantially from that obtained with well known chemical etching and sand blasting processes.
PROPERTIES OF A GLASS SURFACE MODIFIED BY A NEW FROSTING PASTE. DISPERSION OF LIGHT IN THE GLASS NEARSURFACE LAYER
O.N. Sidelnikova*, G.A. Pozdnyakov**, A.N. Salanov, E.A. Suprun, E.M. Pozdnyakov***
(*Institute of Solid State Chemistry and Mechanochemistry, Novosibirsk, Russia; **Khristianovich Institute of Theoretical and Applied Mechanics, Novosibirsk, Russia; ***Institute of Mining, Novosibirsk, Russia)
Glass Ceram., 11-12 (2008) pp. 384-389.
The results of an investigation of the optical properties of a 50-µm thick glass surface layer modified by a new frosting paste are presented. The action of the paste is based on a surface ion-exchange process that results in the formation of a system of microblocks and microcracks. The size distribution function of nonuniform scattering centers and the partial depolarization of the initially linearly polarized light are examined. It is noted that the light scattering characteristics of the modified glass layer are much different from the analogous characteristics of a glass surface which is frosted by chemical etching with a fluorine-containing etchant.
PERFORATED CENOSPHERE-SUPPORTED pH-SENSITIVE SPIN PROBES
E.V. Fomenko*, A.A. Bobko**,***, A.N. Salanov, I.A. Kirilyuk****, I.A. Grigoriev****, V.V. Khramtsov***, A.G. Anshits*
(*Institute of Chemistry and Chemical Technology, Krasnoyarsk, Russia; **Institute of Chemical Kinetics and Combustion, Novosibirsk, Russia; ***Dorothy M. Davis Heart and Lung Research Institute, Ohio State University, Columbus, USA; ****Novosibirsk Institute of Organic Chemistry, Novosibirsk, Russia)
Russ. Chem. Bull., 57(3) (2008) pp. 493-498.
Porous supports with an accessible internal volume and a shell providing the diffusive migration of pH-sensitive spin probes were obtained for the first time from hollow aluminosilicate cenospheres isolated from the coal fly ash. Using the methods of scanning electron microscopy and electron spin resonance, the morphology of different porous cenosphere modifications and its influence on the diffusion of spin probes from the internal volume were studied. When supporting aqueous solutions of a radical, the characteristic diffusion time for the mesoporous structure of the support is longer by a factor of 3–5 than that for the macroporous structure. Ferrospinel in a content of 6 wt % do not virtually affect the diffusion rate of spin probes. A constant rate of radical migration of ~1μmol min−1, determined by radical solubility in water, is achieved when a radical in the solid aggregate state is supported on the magnetic cenospheres.
ELECTRONIC FINGERPRINTING OF ADSORBED SPECIES BY MEANS OF THE SUBSTRATE CORE LEVEL EXCITATION
A.R. Cholach
In “Chemical Reactions on Surfaces”,
Eds. J.I. Duncan, A.B. Klein,
Nova Sci. Publishers, Inc., 2008, Ch. 8, pp. 263-287.
The conjugate electron excitation as a novel kind of electron-solid interaction was developed recently in model studies. This phenomenon enables to fingerprint the electronic valence state structure and thus to ascertain the chemical nature of adsorbed species of any complexity. It also gives potentiality to determine an exact location of adsorbed particle on the composite substrate surface. Disappearance potential spectra duly reveal another substrate electronic peculiarity such as surface and bulk plasmon excitations in addition to regular data on density of the vacant state structure. Besides, the comparison of experimental data and results of adequate quantum-chemical calculations can reveal the location of adsorbed atoms with respect to the top substrate layer, and provides reliable information on the bond nature of adsorbed species. Presented results on the whole evidence for the considerable unity of substrate and adsorbate electronic structures as an essential quality of adsorptive system.
ADVANCED POWER OF DISAPPEARANCE POTENTIAL SPECTROSCOPY IN THE ADSORBED SPECIES IDENTIFICATION
A.R. Cholach
Chem. Phys. Res. J., 2(3-4) (2008) ch. 2, 28 pp.
Advanced power of Disappearance Potential Spectroscopy for fundamental studies of adsorption and surface reaction mechanisms at the molecular level is highlighted. Electronic peculiarities of the adsorbed species can be characterized properly from an extended spectral structure processing due to following reasons. First, because of the pronounced sensitivity of this technique to precious few top sample layers those are exactly responsible for the course of surface reaction. Second, due to availability of the novel kind of electron-solid interaction, namely the conjugate electron excitation developed recently from the model studies. The latter phenomenon consists of ordinary substrate core level excitation accompanied by electron transition from the valence state of adsorbed particle to vacuum level. This is displayed experimentally as a set of spectral satellites localized by the respective ionization potential above the Fermi level of a given substrate component
CONTROL OF PARTICLE SIZE VIA CHEMICAL COMPOSITION: STRUCTURAL AND MAGNETIC CHARACTERIZATION OF Ni-Co ALLOY NANOPARTICLES ENCAPSULATED IN LAMELLAR MIXED OXIDES
K.A. Tarasov*, V.P. Isupov*, B.B. Bokhonov*, Y.A. Gaponov*, B.P. Tolochko*, M.M. Yulikov, V.F. Yudanov, A. Davidson**, P. Beaunier**, E. Marceau**, M. Che**
(*Institute of Solid State Chemistry and Mechanochemistry, Novosibirsk, Russia; **Laboratoire de Reactivite de Surface, Universite Pierre et Marie Curie, Paris, France)
Microporous Mesoporous Mater., 107(1-2) (2008) pp. 202-211.
Nanoparticles of Co-Ni alloys were prepared by thermal decomposition of layered double hydroxides (LDH) containing co-intercalated complexes of two metals. The precursor compounds [LiAl2 (OH)6] 2{Ni1-xCox(EDTA)}·4H2O (where EDTA is ethylenediaminetetraacetate) obtained by anion exchange from [LiAl2(OH)6]Cl·1.5H2O were treated at 450 °C in vacuum. The microstructure of the thermal products was studied using local (TEM, SAED, EDX) as well as integral (XRD, SAXS) methods. It was found that Ni-Co alloy nanoparticles are formed uniformly dispersed in the carbonized matrix of lamellar mixed oxides, and the increase of the relative cobalt content in Ni1-xCOx from x = 0 to 0.86 leads to gradual enlargement of the average alloy particle size from 9 to 16 nm. According to magnetic measurements by SQUID magnetometry and FMR, all alloys, except Ni0.14Co0.86, are superparamagnetic at room temperature. The results on particle size obtained by different techniques are in good agreement. The variation of nanoparticle size via chemical composition in alloys and the use of LDH intercalation matrices is a promising way to synthesize nanocomposites with target properties.
NOVEL CARBONYL COMPLEXES OF RUTHENIUM WITH α-SUBSTITUTED OXIME DERIVATIVES OF TERPENES
I.Yu. Shabalina, V.P. Kirin*, V.A. Maksakov*, A.V. Virovets*, A.V. Golovin, A.M. Agafontsev**, A.V. Tkachev**
(*Nikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia; **Novosibirsk Institute of Organic Chemistry, Novosibirsk, Russia)
Russ. J. Coord. Chem., 34(4) (2008) pp. 286-294.
The reactions of Ru3(CO)12 with 1R,4S,6S-4dimethylamino-4,7,7-trimethylbicyclo[4.1.0]heptane3-one oxime (dimethylaminocaraneoxime) (I), 1R,4S,6S-4-methylamino-4,7,7-trimethylbicyclo [4.1.0]heptane-3-one oxime (methylaminocarane oxime) (II), and 1R, 2R,5R-2-benzylthio-2,6,6trimethylbicyclo[3.1.1]heptane-3-one oxime (benzylthiopinaneoxime) (III) were studied. The binuclear complex Ru2 (CO)4{μ-η3(O,N,X)-L}2 was formed as the main product in every reaction, when Ru3(CO)12 was heated with terpenoid to 80°C. In the above complex, two terpene ligands are coordinated in the form of 'head-to tail' bridge by the oxime groups at a binuclear metal fragment Ru–Ru. The heteroatom of the second functional group of every bridging ligand (nitrogen of amino group in I and II, sulfur of the thio group in III) is additionally coordinated to the ruthenium atom to give the chelate five-membered ring. Also the reactions of terpenoids I, II, III with Ru3(CO)12 were performed at room temperature using Me3NO. In this case, as in the thermal reactions, the main product was the binuclear complex. However, in the reactions of Ru3(CO)12 with I and II, the trinuclear clusters were isolated that readily transformed to binuclear complexes in a solution. The complexes synthesized can exist as two diastereomers due to their chiral metal core. However, in all the cases, only one diastereomer was isolated, which indicates stereospecific nature of the above reactions. The compounds obtained were characterized by IR, 1H-, 13C{1H}-, COSY, and HXCOBI-NMR spectroscopy, the specific optical rotation angles were measured. For the binuclear complexes with ligands I, III and for trinuclear cluster with ligand II, single crystals were obtained and studied by X-ray diffraction.
HIGH VOLUME SYNTHESIS OF SILICON NANOPOWDER BY ELECTRON BEAM ABLATION OF SILICON INGOT AT ATMOSPHERIC PRESSURE
S.P. Bardakhanov*, V.A. Volodin**, M.D. Efremov**, V.V. Cherepkov***, S.N. Fadeev***, A.I. Korchagin***, D.V. Marin**, M.G. Golkovskiy***, Yu.Yu. Tanashev, V.I. Lysenko*,
A.V. Nomoev****, M.D. Buyantuev****, D. Sangaa*****
(*Khristianovich Institute of Theoretical and Applied Mechanics, Novosibirsk, Russia; **Institute of Semiconductor Physics, Novosibirsk, Russia; ***Budker Institute of Nuclear Physics,
Novosibirsk, Russia; ****Buryatian State University, Ulan Ude, Russia; *****Institute of Physics and Technology of Mongolian Academy of Sciences, Ulaanbaatar, Mongolia)
Jpn. J. Appl. Phys., 47(9) (2008) pp. 7019–7022.
The evaporation of high purity silicon ingot was performed in Ar, N2, and air atmospheres using a power electron accelerator. The obtained powders with primary particle sizes of 10-500 nm were investigated using Brunauer-Emmett-Teller analysis (BET), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), photoluminescence measurement, and Raman spectroscopy. The structure and photoluminescence properties of Si(Ar) nanopowder obtained at a large quenching rate differ substantially from those of Si(Ar) and Si(N2) obtained at a smaller quenching rate. Photoluminescence peaks in the visible region of the spectrum are detected at room temperature for the Si(Ar) nanopowders.
STOICHIOGRAPHY AND CHEMICAL METHODS OF PHASE ANALYSIS OF MULTIELEMENT MULTIPHASE SUBSTANCES AND MATERIALS
V.V. Malakhov, I.G. Vasilyeva*
(*Nikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia)
Russ. Chem. Rev., 77(4) (2008) pp. 351-372.
The problems and achievements in the determination of the phase composition of multielement multiphase inorganic solid substances are considered. The problems of theory, methodology and practical use of two chemical methods of phase analysis, viz., selective dissolution and reference-free stoichiographic dissolution are discussed. The unique potential of stoichiography and differential dissolution method, which allows one to overcome many limitations and difficulties typical of modern phase analysis techniques, are demonstrated. Examples of using differential dissolution for the phase analysis of diverse substances and functional materials are given.
LASER-INDUCED LUMINESCENCE OF MODEL Fe/Al2O3 AND Cr/Al2O3 CATALYSTS
V.N. Snytnikov, V.O. Stoyanovsky, T.V. Larina, O.P. Krivoruchko, V.A. Ushakov, V.N. Parmon
Kinet. Catal., 49(2) (2008) pp. 291-298.
The laser-induced luminescence of Cr3+ impurity ions in model Fe/Al2O3 and Cr/Al2O3 catalysts with different calcination temperatures was studied. It was found that an additional luminescence band at 770 nm appeared in the luminescence spectra of low-temperature samples as a result of the interaction of octahedrally coordinated Cr3+ ions with Fe3+ impurity ions. In the θ-Al2O3 phase with a concentration of Cr3+ ions higher than 0.1 wt %, the interaction of the Cr3+- Cr3+ ion pairs in the immediate surroundings resulted in the appearance of N θ lines due to the splitting of R θ lines. The differences of these lines from the Nα lines ofα-Al2O3 were related to the individuality of the crystal lattice of the θ phase and the coordination of Cr3+ impurity ions in the immediate surroundings, which is different from that in the a phase. Based on the laser-induced luminescence spectroscopic data, it was found that regions with a local Cr3+ concentration higher than the average Cr3+ concentration in the bulk of a catalyst by one order of magnitude were formed in theα-Al2O3-Fe2O3 system with the bulk Fe and Cr concentrations of 2.5 and 0.04 wt %, respectively, which was calcined at 1220oC, as a result of the diffusion of chromium and iron ions.
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