An Oxygen Reduction Reaction Kinetic Model for Proton Exchange Membrane Fuel Cells Based on Free Energies of Activation and Adsorption

• Author / Creator

  Ezquerra Silva, Elena

• Polymer electrolyte membrane fuel cells (PEMFCs) are a promising alternative technology
  to internal combustion engines used on vehicles. However, improvements on durability and
  performance are needed in order to boost the commercialization of this technology. The
  oxygen reduction reaction (ORR) is the greatest source of voltage losses, and several studies
  have identified that the catalyst degradation on the cathode is the main contributor to the
  loss of electrochemical surface area (ECSA). Therefore, understanding degradation pathways
  in the ORR kinetics and the activity of the catalyst layer (CL) are a priority for improving
  the performance and durability of PEMFC.
  Three well-known phenomena occur in the oxygen electrochemistry on platinum catalyst:
  i) oxygen reduction reaction (ORR), ii) platinum oxide growth and iii) peroxide formation.
  Many of the elementary steps are common to the three reaction pathways, even though, the
  kinetics of these mechanisms are usually modelled separately. This MSc thesis first analyzes
  and studies novel unified micro kinetic models on ORR available in the literature. Then, it
  derives and implements a new ORR kinetic model that depends only on the activation and
  adsorption energies. Kinetic parameters were estimated by fitting the model to Pt electrode
  experimental data. Comparison between experimental data and proposed model as well as
  other models show that the model is able to capture key steady state characteristics of the
  ORR, and some transient trends.

• Subjects / Keywords

  • Oxygen reduction reaction (ORR)
  • Kinetic model
  • Proton exchange membrane fuel cells (PEMFCs)

• Graduation date

  Spring 2023

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-xgjh-j936

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.