The influence of catalyst layer morphology on the electrochemical performance of DMFC anode
South Africa Institute for Advanced Material Chemistry, Department of Chemistry, University of the Western Cape, Private Bag X17, Bellville, 7535 Cape Town, South Africa
The anodes with different morphology for DMFC were prepared, and the influences of the microstructure of anode catalyst layer on their electrochemical performance were investigated by scanning electrochemical microscopy (SECM), scanning electron microscopy (SEM), proton induced X-ray emission (PIXE) and electrochemical methods, respectively. The surface morphology of catalyst layer was observed by SEM, and the elements dispersion status and its distribution of activity intensity on electrode catalyst layer were mapped by PIXE and SECM, respectively. Electrochemical impedance spectroscopy (EIS) and anode polarization experiment were employed to analyze the electrochemical properties of anode. The results reveal that the anode with a relative smooth surface of catalyst layer and less cracks shows good interfacial properties and the lower resistance on the electrode reaction of methanol, and its maximum power of MEA as a single cell was about 178 mW cm-2 at 70 °C. © 2006 Elsevier B.V. All rights reserved.
Anodes; Electrochemistry; Fuel cells; Scanning electron microscopy; Spectroscopy; X ray analysis; DMFC; Electrode reaction; Scanning electrochemical microscopy (SECM); Catalysts