Search for dissertations about: "pt"

Showing result 11 - 15 of 345 swedish dissertations containing the word pt.

  2. 11. Using Light to Probe Surface Electrochemical Processes

    Author : Weronica Linpe; NanoLund: Centre for Nanoscience; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Electrochemistry; X-ray methods; In situ; synchrotron radiation; Ex situ; Single crystal; polycrystalline; aluminium oxide; Au; Pd; Pt; Sn; Super duplex stainless steel.; Fysicumarkivet A:2021:Linpé;

    Abstract : This thesis shows how various light-based in situ techniques can be used to follow different surface electrochemical processes such as electrochemical deposition into Nanoporous Anodic Aluminium Oxide (NP-AAO) templates and the surface structure of electrodes. Techniques based on both x-rays and visible light were used to follow surface structures and compositions, in situ. READ MORE

  4. 12. Nanostructured Catalysts and Electrode Materials for PEM Fuel Cells

    Author : Kjell Wikander; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; PEMFC; mesoporous; alkylthiol; alkylamine; carbon; microemulsion; Fuel cell; surfactants; nanoparticles; electron microscopy; Pt; nanocasting; silica; cathode; phase transfer method; oxygen reduction;

    Abstract : The Polymer Electrolyte Membrane Fuel Cell (PEMFC) is a promising energy converting technology for powering automotives and electrical equipment using hydrogen gas as fuel and producing water as the only exhaust. The active carbon-supported platinum catalyst present in the electrodes limits the maximum power generation in state-of-the-art PEMFCs due to platinum’s poor activity for the oxygen reduction reaction (ORR) taking place at the cathode. READ MORE

  5. 13. Processing and characterization of thin film field effect gas sensors

    Author : Anna Elisabeth Åbom; Linköpings universitet; []
    Keywords : MISFET; Field effect chemical gas sensors; long-term stability; sputtering; Pt; TiN;

    Abstract : At Applied Physics, Linköping University, the main interest for sensor research has been the focused on MISFET (Metal-Insulator-Semiconductor Field-Effect Transistors) and related devices. The gas sensitivity of MISFET’s was first reported by Lundström et al. in 1975. Today a lot of work is being done in this field. READ MORE

  6. 14. Infrared spectroscopy of O2 and N2 adsorption on the clean and hydrogen covered Pt(111) surface

    Author : Kristian Gustafsson; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Infrared Spectroscopy; Adsorption; Hydrogen; Nitrogen; Pt 111 ; Oxygen;

    Abstract : This thesis is devoted to the investigation of O2and N2 adsorption on the clean and the hydrogen covered Pt(111) surface. Using infrared reflection absorption spectroscopy (IRAS) both physisorbed and chemisorbed molecular adsorptionstates have been identified and characterized via theircharacteristic internal vibration spectra. READ MORE

  7. 15. Low-Energy Modes of Molecules and Atoms Chemisorbed on a Metal Surface. CO and O on Pt(111) Studied by Infrared Spectroscopy

    Author : Ulrika Engström; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; dipole-allowed modes; low-energy modes; carbon monoxide; Infrared spectroscopy; dipole-forbidden modes; Pt 111 ; anti-absorption; Fermi resonance; atomic oxygen;

    Abstract : This thesis is devoted to the investigation of low-energy metal-adsorbate vibrational modes of CO molecules and O atoms chemisorbed on a Pt(111) surface using infrared spectroscopy (IRS). The infrared selection rule states that only vibrational modes having a non-vanishing component of its dynamical dipole moment perpendicular to the surface can be directly excited using IRS, known as dipole-allowed modes. READ MORE