Premium
Non–Pt Catalyst Layer Operation in a PEM Fuel Cell: A Variable‐thickness Regime
Author(s) -
Kulikovsky A.
Publication year - 2016
Publication title -
fuel cells
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.485
H-Index - 69
eISSN - 1615-6854
pISSN - 1615-6846
DOI - 10.1002/fuce.201500207
Subject(s) - proton exchange membrane fuel cell , polarization (electrochemistry) , catalysis , adsorption , cathode , current density , oxygen , chemistry , materials science , fuel cells , current (fluid) , membrane , chemical engineering , analytical chemistry (journal) , thermodynamics , chromatography , physics , organic chemistry , quantum mechanics , engineering , biochemistry
A recently pubilshed experimental polarization curve of a PEM fuel cell with the non–Pt cathode catalyst layer (CCL) exhibits unusual feature: in the region of small current densities, the curve is close to linear. We report a model for the CCL performance which explains this effect. The model includes finite rate of the oxygen adsorption on the catalyst surface. Qualitatively, due to a very high exchange current density of the non–Pt catalyst, the ORR rate close to the membrane is determined by the potential–independent oxygen adsorption rate. This leads to a specific regime of the CCL operation, when only part of the CCL thickness contributes to current production, while the rest part is completely inactive. With the growth of the cell current, the active part increases in width, while the inactive part shrinks. The resulting polarization curve appears to be close to linear.