Molecular Dynamics Simulations on Structural and Mass Transport Properties in the Catalyst Layer of PEMFCs

Abstract

Fuel cells are representative eco-friendly electrochemical devices that convert chemical energy into electrical energy using hydrogen as an energy source. We investigated various factors affecting the performance of the fuel cell in the catalyst layer of polymer electrolyte membrane fuel cell using molecular dynamics simulations. Since the catalyst layer is a key factor in which the electrochemical conversion reaction required for operating the fuel cell occurs, it is essential to understand the molecular transport mechanism in the catalyst layer to optimize the fuel cell performance. In this study, the ionomer film models were constructed based on two types of hydration levels to analyze the effect of the ionomer film thickness and hydration level on the internal nanostructure. In addition, the mechanisms by which these changes in internal nanostructures affect the development of water transport pathways and the transport properties of water molecules, protons, and oxygen were studied.