Publications by authors named "Tamara Krieger"

Synthesis and study of materials based on bismuth cerates and titanates were carried out. Complex oxides BiYTiO were synthesized by the citrate route; BiCeO and BiYCeO-by the Pechini method. The structural characteristics of materials after conventional sintering at 500-1300 °C were studied.

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The mesoporous MgAlO support is promising for the design of efficient and stable to coking catalysts for natural gas and biofuel reforming into syngas. This work aims at doping this support with transition metal cations (Fe, Cr, Ti) to prevent the incorporation of Ni and rare-earth cations (Pr, Ce, Zr), loaded by impregnation, into its lattice along with providing additional sites for CO activation required to prevent coking. Doped MgAlMeO (Me = Fe, Ti, Cr) mesoporous supports prepared by the one-pot evaporation-induced self-assembly method with Pluronic P123 triblock copolymers were single-phase spinels.

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A series of 5%Ni/CeTiO catalysts was prepared with nickel impregnation of mixed Ce-Ti oxides obtained via synthesis in supercritical isopropanol. All oxides have a cubic fluorite phase structure. Ti is incorporated into the fluorite structure.

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Two series of Ni/Ce(Ti/Nb)ZrO catalysts were prepared using citrate route and original solvothermal continuous flow synthesis in supercritical isopropanol and studied in dry reforming of methane (DRM). TEM, XPS and FTIRS of adsorbed CO confirm influence of support composition and preparation method on the catalysts' morphology and surface features. The oxygen mobility was studied by isotope heteroexchange with CO.

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Lanthanide tungstates and molybdates are promising materials for hydrogen separation membranes due to their high protonic conductivity. A promising approach to fabricating ceramics based on these materials is radiation thermal sintering. The current work aims at studying the effect of radiation thermal sintering on the structural morphological and transport properties of (Nd,Ln)(W,Mo)O as promising materials for hydrogen separation membranes.

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Nd tungstates and molybdates are promising materials for hydrogen separation membranes due to their high protonic conductivity. This work aims at elucidating the structural, textural and oxygen transport features of NdWO, NdWMoO and (NdLa)WO and their composites with NiCuO synthesized by mechanical activation. The oxide materials obtained were distorted double fluorites but their composites with NiCuO possess a complex phase composition.

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Metal-organic frameworks (MOFs) possess unique flexibility of structure and properties, which drives them toward applications as water adsorbents in many emerging technologies, such as adsorptive heat transformation, water harvesting from the air, dehumidification, and desalination. A deep understanding of the surface phenomena is a prerequisite for the target-oriented design of MOFs with the required adsorption properties. In this work, we comprehensively study the effect of functional groups on water adsorption on a series CAU-10- substituted with both hydrophilic ( = NH) and hydrophobic ( = NO) groups in the linker.

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Nickel-containing mixed ceria-zirconia oxides also doped by Nb and Ti have been prepared by a citrate route and by original solvothermal continuous flow synthesis in supercritical alcohols. Nickel was subsequently deposited by conventional insipient wetness impregnation. The oxides are comprised of ceria-zirconia solid solution with cubic fluorite phase.

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Thermochemical energy storage (TES) provides a challenging approach for improving the efficiency of various energy systems. Magnesium hydroxide, Mg(OH)2, is known as a suitable material for TES at temperature T>300 °C. In this work, the thermal decomposition of Mg(OH)2 in the absence and presence of sodium nitrate (NaNO3) is investigated to adapt this material for TES at T<300 °C.

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