Search for dissertations about: "transition metal oxides"

Showing result 16 - 20 of 73 swedish dissertations containing the words transition metal oxides.

  2. 16. Resonant Soft X-Ray Emission Spectroscopy of Vanadium Oxides and Related Compounds

    Author : Thorsten Schmitt; Joseph Nordgren; Laurent Duda; Stefan Eisebitt; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics; vanadium oxides; Li-battery; cathode materials; copper oxides; soft X-ray absorption; soft X-ray emission; resonant inelastic X-ray scattering; cluster model calculations; Fysik; Physics; Fysik;

    Abstract : This thesis addresses the electronic structure of vanadium and copper oxides using soft X-ray absorption (SXA) spectroscopy and resonant inelastic X-ray scattering (RIXS) at high brightness synchrotron radiation sources. In RIXS incident photons, tuned to the energy of specific absorption resonances, are inelastically scattered leaving behind a low energy valence excitation in the system studied. READ MORE

  4. 17. Quantum aspects of hydrogen in metals and oxides from density-functional calculations

    Author : Per G. Sundell; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; diffusion; density functional theory; hydrogen; quantum tunneling; electronic structure; perovskite oxide; metal; first-principles; DFT.; ab-initio;

    Abstract : Atomic hydrogen dissolved in a solid or adsorbed on a solid surfacedisplays many remarkable features, and is a subject ofgreat technological interest.An increased understanding of hydrogen/solid systems can supportthe development of areas as diverse asproton exchange membranes for fuel cells,heterogeneous catalysis, and growth of semiconductor devices. READ MORE

  5. 18. Mesoporous transition metal oxides for oxygen electrocatalysis in energy conversion technologies

    Author : Zhixing Wu; Emma Björk; Magnus Odén; Mikhail Vagin; Freddy Kleitz; Linköpings universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Abstract : Electrocatalysis, the foundation of electrical to chemical energy transformation, enables the mitigation of the electrical energy losses during reactions and the control of selectivity of the process to certain chemical products. The slow rate and the multi-step complexity of oxygen-associated reactions, namely oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), motivate the use of platinum group metals (PGM) catalysts, which significantly increase the price of the technologies due to the cost and scarcity of PGM-based materials. READ MORE

  6. 19. Aqueous Exfoliation of Transition Metal Oxides for Energy Storage and Photocatalysis Applications : Vanadium Oxide and Molybdenum Oxide Nanosheets

    Author : Ahmed S. Etman; Junliang Sun; Yury Gogotsi; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; aqueous exfoliation; vanadium oxide nanosheets; molybdenum oxide nanosheets; energy storage; photocatalysis; Inorganic Chemistry; oorganisk kemi;

    Abstract : Two-dimensional (2D) transition metal oxides (TMOs) are a category of materials which have unique physical and chemical properties compared to their bulk counterparts. However, the synthesis of 2D TMOs commonly includes the use of environmental threats such as organic solvents. READ MORE

  7. 20. Structure and Dynamics in Transition Metal Perovskites — An Optical Spectroscopy Study

    Author : Johan Bielecki; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; multiferroics; colossal magnetoresistance; magnetism; proton-conduction; spin-state transition; structure; Ultrafast spectroscopy; high temperature superconductivity; dynamics; Raman;

    Abstract : Transition metal oxides with the perovskite structure exhibit a vast number of exotic properties due to the large number of competing degrees of freedom at the Fermi surface. Together with couplings between and correlations within these degrees of freedom, this class of materials is of high interest from both a practical and theoretical point of view. READ MORE