Sökning: "Heterogeneous reactions"

Visar resultat 6 - 10 av 146 avhandlingar innehållade orden Heterogeneous reactions.

  1. 6. Electrocatalysts for sustainable hydrogen energy : disordered and heterogeneous nanomaterials

    Författare :Joakim Ekspong; Thomas Wågberg; Ludvig Edman; Tomas Edvinsson; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Water splitting; Electrochemistry; Nanomaterials; Density functional theory; Hydrogen evolution; MoS2; Fuel cell; nanomaterials; nanomaterial; fysik; Physics; Physical Chemistry; fysikalisk kemi;

    Sammanfattning : With the current global greenhouse gas emissions, our remaining carbon budget is depleted in only 7 years. After that, several biophysical systems are predicted to collapse such as the arctic ice, coral reefs and the permafrost, leading to potentially irreversible consequences. LÄS MER

  3. 7. Metal-Organic Frameworks (MOFs) for Heterogeneous Catalysis : Synthesis and Characterization

    Författare :Mikaela Gustafsson; Xiaodong Zou; Pascal Van Der Voort; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; metal-organic frameworks; zeolitic imidazolate frameworks; functionalized linkers; structural transformation; heterogeneous catalysis; Structural Chemistry; strukturkemi;

    Sammanfattning : Metal-organic frameworks (MOFs) are crystalline hybrid materials with interesting chemical and physical properties. This thesis is focused on the synthesis and characterization of different MOFs and their use in heterogeneous catalysis. LÄS MER

  4. 8. Homogeneous and Heterogeneous Cluster-Based Catalysts for Asymmetric Reactions

    Författare :Ahmed Fawzy; Kemisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Asymmetric synthesis; hydrogenation; ruthenium; osmium; rhenium; phosphine ligands; chirality.;

    Sammanfattning : Synthesis and characterization of new transition metal carbonyl clusters has been undertaken, and evaluation of the new clusters to act as catalysts/catalysts precursor in asymmetric reactions has been carried out. The catalytic hydrogenation of tiglic acid under relatively mild conditions, using diastereomeric clusters of the general formula [(µ-H)2Ru3(µ3-S)(CO)7(µ-1,2-L)] (L= chiral diphosphine of the ferrocene-based Walphos and Josiphos families) as catalysts, reveal different catalytic behavior in terms of conversion and enantioselectivity. LÄS MER

  5. 9. Advances in Stereoselective Palladium(ΙΙ)-Catalyzed Oxidative Transformations of Allenes

    Författare :Daniels Posevins; Jan-Erling Bäckvall; Troels Skrydstrup; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Synthesis; Palladium Catalysis; Allenes; Biomimetic; Carbocyclization; Borylation; Carbonylation; Oxidation; Heterogeneous; organisk kemi; Organic Chemistry;

    Sammanfattning : Palladium(ΙΙ)-catalyzed carbon-carbon and carbon-heteroatom bond formation via selective C-H bond oxidation constitutes a step-economical and versatile approach towards complex target molecules. This thesis has been focused on the development of new selective palladium(ΙΙ)-catalyzed transformations of allenes under oxidative conditions catalyzed by either homogenous or heterogeneous palladium(ΙΙ) catalysts. LÄS MER

  7. 10. Water splitting by heterogeneous catalysis

    Författare :Henrik Svengren; Mats Johnsson; Tomas Edvinsson; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Faradaic efficiency; electrocatalysis; electrolysis; water oxidation; hydrogen reduction; H2; O2; mass spectrometry; Inorganic Chemistry; oorganisk kemi;

    Sammanfattning : A sustainable solution for meeting the energy demands at our planet is by utilizing wind-, solar-, wave-, thermal-, biomass- and hydroelectric power. These renewable and CO2 emission-free energy sources are highly variable in terms of spatial and temporal availability over the Earth, introducing the need for an appropriate method of storing and carrying energy. LÄS MER