Simulator for Chemical Membrane Degradation in LT-PEMFCs

This page allows modelling chemical membrane degradation in low temperature proton exchange membrane fuel cells based on the following set of chemical equations:

The set of reactions starts with the Fenton reaction (Equation (1)) in which a ferrous ion reacts with hydrogen peroxide to form a hydroxyl radical. Equations (2) – (13) describe the formation of additional radical species, the reactions of the radical species with other constituents of the system or with each other. The last 4 equations ((14) – (16) and (unzipping)) express the reactions of hydroxyl radicals with the ionomer membrane.

Temperature-dependence of the rate constants is expressed via the Arrhenius law

with k_n = rate constant for the n-th reaction [L mol^-1 s^-1] or [s^-1], A_n = pre-exponential factor for the n-th reaction [L mol^-1 s^-1] or [s^-1], E_a,n = activation energy for the n-th reaction [J mol^-1], R = gas constant (8.314 J K^-1 mol^-1) and T = temperature [K].

The concentrations of iron contaminants (Fe²⁺ and Fe³⁺) as well as the concentration of H₂O₂, H₂ and O₂ can be chosen freely. Furthermore, the concentration of the head groups (SC-SO₃H) can be set to a desired value. Kinetic data (activation energies, pre-exponential factor) are set to fixed values.

Graphs showing the concentrations of the individual species versus time are received as output. In addition, the input file for COPASI and the result files (concentrations and fluoride emission rates) can be downloaded.