Search for dissertations about: "Hydrogen Diffusion"

Showing result 1 - 5 of 123 swedish dissertations containing the words Hydrogen Diffusion.

  2. 1. Hydrogen in nano-sized metals : Diffusion and hysteresis effects

    Author : Wen Huang; Björgvin Hjörvarsson; Max Wolff; Gavin Walker; Uppsala universitet; []
    Keywords : Hydrogen; diffusion; hysteresis; optical technique; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Abstract : Metal hydrides can be used as hydrogen storage materials for fuel cells and batteries, and as sensors for detecting hydrogen gas. The use of metal hydrides for hydrogen storage can be hindered by poor kinetics and low capacity. Moreover, poor sensitivity, long recovery and response time, limit the applications of metal hydrides as hydrogen sensors. READ MORE

  4. 2. Theory of Hydrogen Quantum Diffusion

    Author : Thomas Mattsson; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; path-integrals; isotope effect; transition state theory; quantum; diffusion; hydrogen; first-principles calculations; nickel;

    Abstract : Atomic hydrogen adsorbed on a metal surface is one of the simplest possible examples of chemisorption, yet it is very challenging. The adsorption and the very elementary process of surface diffusion, a single atomic jump, have been investigated theoretically using several methods. READ MORE

  5. 3. Insights into Materials Properties from Ab Initio Theory : Diffusion, Adsorption, Catalysis & Structure

    Author : Andreas Blomqvist; Rajeev Ahuja; Christopher Wolverton; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Density functional theory; Molecular dynamics; Diffusion; Catalysis; Adsorption; Random structure search; Hydrogen-storage materials; Phase-change materials; Defects and diffusion; Defekter och diffusion; Surfaces and interfaces; Ytor och mellanytor; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Abstract : In this thesis, density functional theory (DFT) calculations and DFT based ab initio molecular dynamics simulations have been employed in order to gain insights into materials properties like diffusion, adsorption, catalysis, and structure. In transition metals, absorbed hydrogen atoms self-trap due to localization of metal d-electrons. READ MORE

  6. 4. Transition state theory from path-integrals, application to hydrogen diffusion on Ni(100)

    Author : Thomas R. Mattson; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; polaron; hydrogen; quantum; diffusion; monte carlo; path-integrals;

    Abstract : .... READ MORE

  7. 5. Metal Hydrogen Interaction and Structural Characterization of Amorphous Materials from first principles

    Author : Robert Johansson; Ralph Scheicher; Olle Eriksson; Rajeev Ahuja; Peter Mohn; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; hydrogen; vanadium; zintl; laves; strain; diffusion; amorphous; dft; molecular dynamics; md; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Abstract : In this thesis, first-principles calculations based on density functional theory have been employed to investigate metal hydrogen interaction in transition, p-block and rare earth metals. Furthermore, the accuracy of the stochastic quenching method was tested in describing the structure of amorphous Fe(1-x)Zrx. READ MORE