Search for dissertations about: "Electrochemically Active Surface Area"

Showing result 1 - 5 of 7 swedish dissertations containing the words Electrochemically Active Surface Area.

  1. 1. Bioaccessibility of Stainless Steels Importance of Bulk and Surface Features

    University dissertation from Stockholm : KTH

    Author : Gunilla Herting; KTH.; [2008]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Stainless steel; iron; chromium; nickel; corrosion; metal release; artificial rain; synthetic body fluids; acetic acid; surface oxide; surface finish; NATURAL SCIENCES Chemistry Physical chemistry Surface and colloid chemistry; NATURVETENSKAP Kemi Fysikalisk kemi Yt- och kolloidkemi;

    Abstract : With increasing environmental awareness, the desire to protect human beings and the environment from adverse effects induced by dispersed metals has become an issue of great concern and interest. New policies, such as REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) within the European Community, have been implemented to reduce hazards posed by the use of chemicals on producers and downstream users. READ MORE

  2. 2. The Impact of Hydrocarbon and Carbon Oxide Impuritiesin the Hydrogen Feed of a PEM Fuel Cell

    University dissertation from Stockholm : KTH Royal Institute of Technology

    Author : Katrin Kortsdottir; KTH.; [2016]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fuel Cell; Hydrogen Impurities; Carbon Monoxide; Carbon Dioxide; Ethene; Propene; Methane; Propane; Toluene; Electrochemically Active Surface Area; Cyclic Voltammetry; Mass Spectrometry; bränslecell; vätgasföroreningar; kolmonoxid; koldioxid; eten; propen; metan; propan; toluen; elektrokemisk aktiv yta; cyklisk voltammetri; masspektrometri; Chemical Engineering; Kemiteknik;

    Abstract : The proton exchange membrane fuel cell generates electricity from hydrogen and oxygen (from air) through electrocatalytic reactions in an electrochemical cell. The Pt/C catalyst, commonly used in PEM fuel cells, is very sensitive to impurities that can interact with the active catalyst sites and limit fuel cell performance. READ MORE

  3. 3. Electrochemical Reactions in Polymer Electrolyte Fuel Cells

    University dissertation from Stockholm : KTH

    Author : Maria Wesselmark; KTH.; [2010]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fuel cell; model electrodes; oxygen reduction; methanol oxidation; formic acid oxidation; hydrogen oxidation; CO oxidation; degradation; tungsten oxide; carbon support; Bränslecell; modellelektroder; syrgasreduktion; metanoloxidation; myrsyraoxidation; vätgasoxidation; CO oxidation; degradering; wolfram oxid; kolsupport; TECHNOLOGY Chemical engineering; TEKNIKVETENSKAP Kemiteknik;

    Abstract : The polymer electrolyte fuel cell converts the chemical energy in a fuel, e.g. hydrogen or methanol, and oxygen into electrical energy. The high efficiency and the possibility to use fuel from renewable sources make them attractive as energy converters in future sustainable energy systems. READ MORE

  4. 4. MEMS-based electrochemical gas sensors and wafer-level methods

    University dissertation from Stockholm : KTH Royal Institute of Technology

    Author : Hithesh K Gatty; KTH.; [2015]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MEMS; gas sensors; electrochemical; nitric oxide; hydrogen sulphide; nafion; nano;

    Abstract : This thesis describes novel microel ectromechanical system (MEMS) based electrochemical gas sensors and methods of fabrication.This thesis presents the research in two parts. In the first part, a method to handle a thin silicon wafer using an electrochemically active adhesive is described. READ MORE

  5. 5. Electrode degradation in proton exchange membrane fuel cells

    University dissertation from Stockholm : KTH Royal Institute of Technology

    Author : Alejandro Oyarce; KTH.; [2013]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; PEMFC; PEFC; Porous electrodes; Carbon corrosion; Carbon nanotubes; Carbon fibers; Polyhedral carbon nanofoams; Phosphonated hydrocarbon ionomer; Mass-transport losses; Electrode morphology; Electrode collapse; Start-up and shut-down; System strategies; Stainless steel; Bi-polar plates; In-situ contact resistance.;

    Abstract : The topic of this thesis is the degradation of fuel cell electrodes in proton exchange membrane fuel cells (PEMFCs). In particular, the degradation associated with localized fuel starvation, which is often encountered during start-ups and shut-downs (SUs/SDs) of PEMFCs. At SU/SD, O2 and H2 usually coexist in the anode compartment. READ MORE