Proton exchange membrane fuel cells Energy conversion Chemical Engineering
Proton-exchange membrane fuel cells (PEMFCs) are promising as high-efficiency energy conversion devices, but the need for expensive noble metal catalysts such as Pt has hindered commercialization. An alternative is the alkaline membrane fuel cell (AMFC), which intrinsically possesses faster kinetics at the cathode, enabling noble metals to be replaced by Co, Ag, Fe, or Ni. In order to compete with PEMFCs (i.e. achieve 1.0 W/cm2 power density), AMFCs require improved membranes. In particular, membranes must achieve conductivities of ~0.1 S/cm and be thermally, chemically, and mechanically stable. The membrane mass transport phenomena governing conduction should be clearly understood in order to efficiently develop new materials. In particular, there is need for an improved, molecularlevel understanding of the relationship between membrane water content and membrane conductivity, as well as an elucidation of the kinetic mechanism causing membrane carbonation. The dependency of conductivity on membrane water content is explored using Fourier Transform Infrared Attenuated Total Reflectance (FTIR-ATR) spectroscopy with twodimensional correlation techniques, and Electrochemical Impedance Spectroscopy (EIS). The particular role that specific water cluster states play during transport is elucidated, and the transient behavior associated with membrane carbonation is explored.
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Title
Transport in fuel cell ion exchange membranes
Creators
Erich J. Mace - DU
Contributors
Yossef A. Elabd (Advisor) - Drexel University (1970-)
Awarding Institution
Drexel University
Degree Awarded
Master of Science (M.S.)
Publisher
Drexel University; Philadelphia, Pennsylvania
Resource Type
Thesis
Language
English
Academic Unit
Chemical (and Biological) Engineering [Historical]; College of Engineering (1970-2026); Drexel University