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Showing result 1 - 5 of 48 swedish dissertations matching the above criteria.

  1. 1. Structure and Properties Investigations of the La2Co1+z(Ti1-xMgx)1-zO6 Perovskite System

    Author : Samrand Shafeie; Gunnar Svensson; Mari-Ann Einarsrud; Mats Johnsson; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; solid oxide fuel cell; SOFC; LaCoO3; cobaltates; cobalt oxide; perovskite; XANES; XRD; Neutron powder diffraction; thermal expansion; electronic conductivity; magnetism; citrate; electron diffraction; synthesis; phase diagram; spin state; fast fas oxid bränslecell; LaCoO3; koboltoxid; perovskit; XANES; XRD; neutron diffraktion; elektron diffraktion; termisk expansion; elektrisk ledningsförmåga; magnetism; citrat; SOFC; syntes; fasdiagram; spin tillstånd; Solid state chemistry; Fasta tillståndets kemi; Materials chemistry; Materialkemi; Structural Chemistry; strukturkemi; Materials Chemistry; materialkemi;

    Abstract : Perovskite based materials have great potentials for various energy applications and the search for new materials for uses in SOFCs has largely been concentrated to this class of compounds. In this search, we have studied perovskite phases in the system La2Co1+z(Ti1-xMgx)1-zO6, with 0  x 0.9 and z = 0.0, 0. READ MORE

  2. 2. Properties in New Complex Perovskite-Related Materials, a Matter of Composition and Structure

    Author : Samrand Shafeie; Gunnar Svensson; Jekabs Grins; John T. S. Irvine; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Perovskite; XANES; XRPD; NPD; TEC; TEM; SEM; TGA; SAED; HREM; thermal expansion; Seebeck coefficient; electronic conductivity; SOFC materials; magnetic susceptibility; Perovskit; XANES; XRPD; NPD; TEC; TEM; SEM; TGA; SAED; HREM; termisk expansion; Seebeck koefficient; elektrisk ledningsförmåga; SOFC material; magnetiska egenskaper; Materials Chemistry; materialkemi;

    Abstract : This PhD thesis presents investigations of perovskite-related compounds in systems of interest for applications in components in solid oxide fuel cells. The compound compositions derive from substitutions in the parent compounds LaCoO3, LaCrO3 and SrFeO3. READ MORE

  3. 3. Preparation and Characterization of Lead Halide Perovskites : Towards sustainable, cost-effective and upscalable solar cell manufacture

    Author : Kári Sveinbjörnsson; Erik Johansson; Pablo Docampo; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; perovskite solar cells; perovskite; photoconductivity; carbon nanotubes; transparent contact; ambient processing; water-based; Chemistry with specialization in Physical Chemistry; Kemi med inriktning mot fysikalisk kemi;

    Abstract : The perovskite solar cell (PSC) is a recent contender within the photovoltaic research field. In a matter of a few years, the power conversion efficiency (PCE) of the PSC has catapulted from 4% to above 22%, which represents one of the fastest developments in the field. READ MORE

  4. 4. Electron-Phonon Interactions in Transition Metal Oxides Studied by Resonance Raman Scattering

    Author : Jakob Andreasson; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Franck-Condon; Fr ohlich interaction; higher order scattering; perovskite; transition metal oxide; two-phonon; oxygen breathing mode; Raman spectroscopy;

    Abstract : In this thesis, studies of strong electron-phonon interactions in a number of transition metal oxides are presented. Two different electron-phonon interaction mechanisms are identified; Franck-Condon scattering and infrared active longitudinal optical (IR LO) two-phonon activation. READ MORE

  5. 5. Beyond average crystal structures: understanding extended and local environments in proton-conducting Sc-substituted BaTiO3 perovskites

    Author : Nico Torino; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; proton conducting oxide; IR; thermogravimetry; perovskite; neutron scattering; Raman; Reverse Monte Carlo; ordering; BaTiO3;

    Abstract : Proton conducting ceramics are very promising for applications concerned with energy sourcing with cleaner, safer, more abundant and cheaper alternatives to fossil fuels. These materials are still in development and advances in the field depend on a better understanding of the role of defects, their identification and location in the host framework, and the assessment of their short- and long-range dynamics and kinetics. READ MORE