Modeling nanostructured catalyst layer in PEMFC and catalyst utilization

Abstract

A lattice model of the nanoscaled catalyst layer structure in proton exchange membrane fuel cells (PEMFC) was established by Monte Carlo method. The model takes into account all the four components in a typical PEMFC catalyst layer: platinum (Pt), carbon, ionomer and pore. The elemental voxels in the lattice were set fine enough so that each average sized Pt particulate in Pt/C catalyst can be represented. Catalyst utilization in the modeled catalyst layer was calculated by counting up the number of facets of Pt voxels where “three phase contact” are met. The effects of some factors, including porosity, ionomer content, Pt/C particle size and Pt weight percentage in the Pt/C catalyst, on catalyst utilization were investigated and discussed.

Key words： catalyst layer; PEM fuel cell; lattice model; Monte Carlo method; catalyst utilization

Acknowledgment

This research was financially supported in part by funds from the National Natural Science Foundation of China (Grant No. 20606025) and the Project of Creative Research Groups from Universities (IRT0641).

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