Sökning: "fotosyntes kemi"

Visar resultat 1 - 5 av 10 avhandlingar innehållade orden fotosyntes kemi.

  1. 1. (Photo)electrochemical Water Oxidation: From Catalysis to Functional Device

    Författare :Hao Yang; Licheng Sun; Marc Koper; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; artificial photosynthesis; solar fuels; water oxidation; nucleophilic attack; conjugated microporous polymer; host-guest chemistry; photoanode; perovskites; artificiell fotosyntes; solbränslen; vattenoxidation; nukleofil attack; konjugerad mikroporös polymer; värd-gästkemi; fotoanoder; perovskiter; Kemi; Chemistry;

    Sammanfattning : The key challenge within artificial photosynthesis is achieving efficient electro- or photo-driven water oxidation catalysis, a necessary process to supply the protons for the reduction reactions, thereby enabling solar fuel production. To facilitate efficient water (photo)electrolysis for solar fuel production, this thesis focuses on two aspects: 1) elucidating the O-O bond formation mechanism and developing efficient, stable, and economical water oxidation catalysts (WOCs); 2) exploring stable, low-cost, light-absorbing photoanode materials that have suitable band structures and excellent charge diffusion properties. LÄS MER

  3. 2. Towards Artificial Photosynthesis: Exploration of Efficient First-Row Transition Metal-Based Water Oxidation Catalysts

    Författare :Lizhou Fan; Licheng Sun; Thomas Wågberg; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Artificial photosynthesis; Water oxidation; Heterogeneous catalyst; Electrochemistry; Electronic structure; Kemi; Chemistry;

    Sammanfattning : Artificial photosynthesis provides a promising strategy for sustainable energy harvesting, yet its overall efficiency is limited by the water oxidation reaction. The subject of this thesis focuses on the exploration of highly efficient cost-effective heterogeneous catalysts for water oxidation, and the investigation of essential catalyst structure-activity relationships. LÄS MER

  4. 3. Computational Studies on Homogeneous Water Oxidation Catalysts

    Författare :Ge Li; Mårten S. G. Ahlquist; Moyses Araujo; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Computational studies; homogeneous; water oxidation catalysts; ruthenium; iron; mechanisms; Teoretisk kemi och biologi; Theoretical Chemistry and Biology;

    Sammanfattning : To combat the increasing energy demand and climate change, artificial photosynthesis is a promising approach to producing renewables by storing energy into chemicals and fuels. Water oxidation, responsible for offering electrons and protons to the reduction reactions, suffers from slow kinetics. LÄS MER

  5. 4. Photophysics and Photochemistry of Iron Carbene Complexes

    Författare :Linnea Lindh; NanoLund: Centre for Nanoscience; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; tidsupplöst spektroskopi; täthetsfunktionalteori; järn-komplex; färgämne; grätzelsolcell; fotokatalys; elektronöverföringsreaktion; time-resolved spectroscopy; density functional theory; earth-abundant; iron-complex; photosensitiser; dye-sensitised solar cell; photocatalysis; electron transfer;

    Sammanfattning : Nature captures sunlight via light-absorbing molecules.Similarly, photosensitisers are used in applications of solar cells and artificial photosynthesis to absorb sunlight, and transfer the excited electron. LÄS MER

  7. 5. Xanthophyll Cycle in the Light of Thylakoid Membrane Lipids - Membrane Packing, Curvature Elastic Stress and Enzyme Binding

    Författare :Anna Szilagyi; Biokemi och Strukturbiologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; steroider; Lipids; steroids; membranes; Lipider; enzymologi; HPLC; laurdan; fluorescence spectroscopy; Proteins; enzymology; Proteiner; curvature elastic stress; enzyme binding; thylakoid membrane; membrane fluidity; lipid packing; histidine; VDE; zeaxanthin; xanthophyll cycle; mebran;

    Sammanfattning : The xanthophyll cycle involves the light-dependent and reversible conversion of violaxanthin to zeaxanthin. The enzyme, violaxanthin de-epoxidase (VDE) catalyses the conversion of violaxanthin to zeaxanthin, via the intermediate antheraxanthin. VDE is a membrane-hosted enzyme during its activity. LÄS MER