Sökning: "Kemi med inriktning mot materialkemi"

Visar resultat 1 - 5 av 37 avhandlingar innehållade orden Kemi med inriktning mot materialkemi.

  1. 1. Carbothermal synthesis of nano-structured metal, carbides and nitrides, using solution processed precursors; from precursor to product

    Författare :Sarmad Naim Katea; Gunnar Westin; Hilmar Vidarsson; Sanjay Mathur; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Solution-based chemical processing; sol-gel; ceramic powders; transition metal carbides and nitrides; sintering; nickel binder; mechanical properties; Chemistry with specialization in Inorganic Chemistry; Kemi med inriktning mot oorganisk kemi;

    Sammanfattning : This thesis describes how solution chemical based carbothermal syntheses can be used for the synthesis of nanostructured zirconium carbide and nitride nanophase powders as well as a nickel-metal coating on NbC for use as a sintering agent. The focus is on the development of novel synthesis routes using atomic or small nanoscale level mixing of the metal oxide and carbon source in the starting precursors, enabling the use of lower synthesis temperatures and non-agglomerated nanosized powders. LÄS MER

  2. 2. Transition metal and alloy catalysts in the light of computational materials modelling

    Författare :Ageo Meier de Andrade; Peter Broqvist; Jolla Kullgren; Elsebeth Schröder; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; density functional theory; dispersion corrections; density functional analysis; transition metal; alloys; work function; lignin valorization; keto-enol tautomerization; Kemi med inriktning mot materialkemi; Chemistry with specialization in Materials Chemistry;

    Sammanfattning : This thesis is built around two pillars. One is heterogeneous catalysis in the broader context of green chemistry. The focus here is on identifying catalytically active materials suitable for the valorization of renewable feedstocks. LÄS MER

  3. 3. Insights in Li-ion Battery Interfaces through Photoelectron Spectroscopy Depth Profiling

    Författare :Bertrand Philippe; Kristina Edström; Danielle Gonbeau; Hakan Rensmo; Rémi Dedryvère; Rosa Palacin; Maria Alfredsson; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Lithium-ion batteries; negative electrodes; silicon; MnSn2; SEI; PES; XPS; synchrotron; Chemistry with specialization in Inorganic Chemistry; Kemi med inriktning mot oorganisk kemi;

    Sammanfattning : Compounds forming alloys with lithium, such as silicon or tin, are promising negative electrode materials for the next generation of Li-ion batteries due to their higher theoretical capacity compared to the current commercial electrode materials.An important issue is to better understand the phenomena occurring at the electrode/electrolyte interfaces of these new materials. LÄS MER

  4. 4. Characterization of Reaction Products in the Li-O2 Battery Using Photoelectron Spectroscopy

    Författare :Reza Younesi; Kristina Edström; Patrik Johansson; Fredrik Björefors; Gabriel Veith; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Li-O2 Battery; Surface Characterization; Lithium-Air Battery; Photoelectron Spectroscopy; XPS; Kemi med inriktning mot materialkemi; Chemistry with specialization in Materials Chemistry; Chemistry with specialization in Physical Chemistry; Kemi med inriktning mot fysikalisk kemi;

    Sammanfattning : The rechargeable Li-O2 battery has attracted interest due to its high theoretical energy density (about 10 times better than today’s Li-ion batteries). In this PhD thesis the cycling instability of the Li-O2 battery has been studied. LÄS MER

  5. 5. The Electronic Structure of Organic Molecular Materials : Theoretical and Spectroscopic Investigations

    Författare :Iulia Emilia Brumboiu; Barbara Brena; Biplab Sanyal; Olle Eriksson; Jakob Schiøtz; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; NATURAL SCIENCES; materials theory; electronic structure; photoelectron spectroscopy; near-edge X-ray absorption fine structure; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik; Materialvetenskap; Materials Science;

    Sammanfattning : In the present thesis the electronic properties of two organic molecules were studied by means of density functional theory (DFT) in connection to their possible applications in organic photovoltaics and molecular spintronics respectively.The first analysed system is the C60 derivative PCBM extensively used in polymer solar cells for the charge separation process. LÄS MER