Dynamic electrochemical impedance spectroscopy of Pt/C-based membrane-electrode assemblies subjected to cycling protocols

作者：Darab Mahdi; Dahlstrom Per Kristian; Thomassen Magnus Skinlo; Seland Frode; Sunde Svein^*

来源：Journal of Power Sources, 2013, 242: 447-454.

DOI：10.1016/j.jpowsour.2013.05.105

• Electrocatalyst
• PEMFC
• Pt nanoparticles
• dEIS
• Activation

A PEM fuel cell membrane electrode assembly (MEA) was characterized by dynamic electrochemical impedance spectroscopy (dEIS) before and after cycling in a single cell configuration. The cell was subjected to 100 cycles between 0.6 V and 1.5 V vs. RHE in N-2/5% H-2 and 80 degrees C and 100% RH. Initially, the impedance-plane plots contained first- and fourth-quadrant behavior, which is resulting from a reaction mechanism at the cathode involving adsorbed intermediates. After the cycling, the impedance spectra changed to display first-quadrant behavior only. This is suggested to be due to particle growth and possibly the formation of edges between agglomerated particles. The results show that dEIS is a sensitive technique to detect even very moderate changes in electrocatalyst structure.

• 出版日期2013-11-15