Simulation of the catalyst layer in PEMFC based on a novel two-phase lattice model

A lattice model of catalyst layer in proton exchange membrane fuel cells (PEMFCs), consisting of randomly distributed catalyst phase (C phase) and mixed ionomer-pore phase (IP phase), was established by means of Monte Carlo method. Transport and electrochemical reactions in the model catalyst layer were calculated. The newly proposed C-IP model was compared with previously established pore-solid two phase model. The variation of oxygen level and reaction rate along the thickness of catalyst layer with cell current was discussed. The effect of ionomer distribution across catalyst layer was studied by comparing profiles of oxygen level, reaction rate and overpotential, as well as corresponding polarization curves.

► We propose a novel two phase lattice model of catalyst layer in PEMFC.
► The model features a catalyst phase and a mixed ionomer and pores phase.
► Transport and electrochemical reaction in the lattice are simulated.
► The model enables more accurate results than pore-solid two phase model.
► Profiles of oxygen level and reaction rate across catalyst layer vary with cell current.