Search for dissertations about: "point defects, DFT"

Showing result 1 - 5 of 16 swedish dissertations containing the words point defects, DFT.

  2. 1. On hydrogen point defects in perovskite oxides

    Author : Erik Jedvik Granhed; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; density functional theory; oxyhydride; phonon; point defects; chemical expansion; polaron; BaZrO3; proton conductor; BaTiO3;

    Abstract : Oxides based on the perovskite structure exhibit a surprisingly large diversity in materials properties and are found in many different applications, several related to clean energy technologies, such as solar cells, batteries and fuel cells. Many properties in materials are the result of lattice imperfections, commonly denoted \emph{defects}, and much effort is devoted to fine tuning materials properties through controlling the defects therein. READ MORE

  4. 2. Point defects and ion conduction in solid oxides: a first-principles case study of La2Zr2O7

    Author : Joakim Nyman; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; proton; self compensation; hydrogen economy; DFT; La2Zr2O7; acceptor doping; lanthanum zirconate; oxygen vacancy; SOFC; pyrochlore; point defect; trapping; computational methods; solid oxide; charge compensation; first principles; ion conduction; solid oxide fuel cell; ceramic electrolyte; defect cluster; fuel cell; hydrogen;

    Abstract : In the endeavor to attain a clean environment and sustainable energy consumption, the notion of a future hydrogen economy stands out as one of the grandest visions. Striving for this vision, a critical task lies in optimizing the performance of the fuel-cell devices responsible for extracting electric power from the energy stored in hydrogen molecules. READ MORE

  5. 3. First principles study of tungsten-based alloys: From defect thermodynamics to phase diagrams

    Author : Leili Gharaee; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; structural materials; first-principles calculations.; point defects; tungsten alloys; irradiation;

    Abstract : Nuclear fusion is a very attractive option for energy production as it is clean, safe and efficient. The major obstacle in construction of fusion power plants is the development of materials that can tolerate the extreme operational condition especially high-energy neutron flux. READ MORE

  6. 4. On the defective origin of conductive and structural properties of oxides: insights from first principles

    Author : Anders Lindman; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; point defects; thermodynamic modeling; proton conductors; oxyhydrides; density-functional theory; BaZrO3; polarons; grain boundaries; space charges; oxides;

    Abstract : Oxides are versatile materials with applications in many different research fields; especially those related to clean energy technologies, such as fuel cells, batteries and solar panels. Many functional properties of these materials derive from lattice imperfections, or defects, and a lot of effort has been put into fine tuning these materials by modifying their structure on the atomic scale. READ MORE

  7. 5. Ab initio based modeling of defects and disorder in industrial materials

    Author : Yunguo Li; Pavel Korzhavyi; Tony Paxton; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Teknisk materialvetenskap; Materials Science and Engineering;

    Abstract : The study of defects and disorder in condensed matter remains a central subject of materials science. Newly emerging experimental and theoretical techniques promote our understanding in this field, and reveal many interesting phenomena in which the atomic picture plays a crucial role. READ MORE