Effect of a thermal treatment on the activity of carbon-supported Pt, Pt+W and Pt+Mo electrocatalysts for methanol oxidation reactions

Date

2001-12-01

Author

Gokagac, G
Leger, JM
Hahn, F

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Previous studies on carbon supported Pt, Pt+W and Pt+Mo indicated that Pt+Mo was the most active electrocatalyst at low potentials and that Pt+W has similar properties as pure Pt in methanol oxidation. Those samples were thermally treated at 900 degreesC in a hydrogen gas atmosphere for 6 hours to observe the effect on metal particle sizes and on their distribution on carbon support. It was found that thermally treated Pt+Mo/XC-72 remains the most active catalyst at all potentials compared to the other heated samples. The heat treatment caused the sintering of small particles leading to a decrease in activity of the catalysts except Pt+Mo/XC-72. The heat treated samples were characterised by voltammetry, X-ray diffraction, transmission electron microscopy and energy dispersive X-ray analysis techniques. The methanol oxidation reaction was followed by in-situ FTIR spectroscopy to identify products and adsorbed species on the surface of electrode.

Subject Keywords

Methanol oxidation, Infrared reflectance spectroscopy, Carbon-supported catalysts

URI

https://hdl.handle.net/11511/67015

Journal

ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES

Collections

Department of Chemistry, Article

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Citation Formats

G. Gokagac, J. Leger, and F. Hahn, “Effect of a thermal treatment on the activity of carbon-supported Pt, Pt+W and Pt+Mo electrocatalysts for methanol oxidation reactions,” ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES, pp. 1306–1314, 2001, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/67015.