Sökning: "Heterogeneous catalyst"

Visar resultat 21 - 25 av 100 avhandlingar innehållade orden Heterogeneous catalyst.

  1. 21. Operando X-ray Absorption Spectroscopy Studies of Methane Oxidation Catalysts

    Författare :Johan Nilsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; operando spectroscopy; XAS; palladium; heterogeneous catalysis; methane oxidation; XAFS;

    Sammanfattning : Operando spectroscopy is an experimental method in catalysis that combines measurements of catalytic activity and selectivity with simultaneous in situ spectroscopic characterization of the catalyst. Since the structure and composition of the catalyst are probed under reaction conditions, the method can provide valuable information to elucidate the mechanism of the studied reaction. LÄS MER

  2. 22. Studies of Molecular Interactions with Single Nanoparticles: Combining in Situ Plasmonic Nanospectroscopy with Transmission Electron Microscopy

    Författare :Sara Nilsson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; oxidation; plasmonic nanospectroscopy; heterogeneous catalysis; localized surface plasmon resonance sensing; grain boundary; transmission electron microscopy; single nanoparticle; palladium hydride; dark-field scattering spectroscopy;

    Sammanfattning : The cyclic methanol and hydrogen economies are two viable options in the strive for clean energy production. Industrial methanol synthesis is conducted over copper (Cu)-based catalysts. However, Cu is prone to oxidation, which leads to Cu catalyst deactivation. LÄS MER

  3. 23. Catalytic and Electrocatalytic Transformations with Palladium and Nickel : Scope and mechanistic investigations

    Författare :Alejandro Valiente Sánchez; Belén Martín-Matute; King Kuok (Mimi) Hii; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Organic Chemistry; Heterogeneous Catalysis; Metal-organic frameworks; Nickel; Palladium; Electrocatalysis; Cross-coupling; Hydrogenation; organisk kemi; Organic Chemistry;

    Sammanfattning : The work presented in this thesis is based on methodology development and mechanistic investigations using heterogeneous palladium and nickel catalysts. Following the introduction (Chapter 1), Chapter 2 presents a summary of the synthesis and characterization of the MOF-supported Pd catalysts (Pd @ MOF) that are used in this thesis. LÄS MER

  4. 24. Surface structure and catalytic activity of Pd and Fe oxide surfaces and thin films

    Författare :Mikhail Shipilin; Synkrotronljusfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Surface X-ray diffraction SXRD ; Heterogeneous catalysis; Pd; PdO; Fe; FeO; Thin films; Fysicumarkivet A:2016:Shipilin;

    Sammanfattning : The present work is devoted to atomic scale structural studies of the surfaces of model heterogeneous catalysts relevant to oxidation reactions. A novel approach using high-energy surface X-ray diffraction combined with mass-spectrometry measurements is employed to perform in situ structural characterization of Pd(100) and Pd(553) single crystal surfaces acting as catalysts in the process of CO oxidation under semirealistic conditions. LÄS MER

  5. 25. Kinetics of Nanoparticle Catalysis from First Principles

    Författare :Mikkel Jørgensen; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Density functional Theory; Mean field approximation; Acetylene hydrogenation; Kinetic Monte Carlo; CO oxidation; Entropy; Methane oxidation; Heterogeneous catalysis; Kinetic modeling; Nanoparticles;

    Sammanfattning : Modern society depends heavily on heterogeneous catalysis, which creates strong economical and environmental incentives to improve catalyst efficiency. Heterogeneous catalysts are often realized as metal nanoparticles (NPs) supported on oxide surfaces, and catalysts are traditionally developed by trial and error approaches. LÄS MER