Modification of surface activity of Cu-Zr amorphous alloys and Cu metal by electrochemical methods

M. Janik-Czachor, A. Kudelski, M. Dolata, M. Varga, A. Szummer, J. Bukowska, Á Molnár

Research output: Contribution to journalArticle

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Abstract

This paper summarizes our attempts to use some strictly controlled electrochemical processes of dissolution/redeposition of Cu (including disproportionation of Cu+ to Cu metal and Cu2+) to modify Cu surfaces, as well as surfaces of Cu base amorphous alloys (AA), to produce active substrates for various phenomena of adsorption and catalytic reactions. We developed some new methods of activation of the Cu substrate for in situ investigations of adsorbates with SERS (Surface Enhanced Raman Spectroscopy). The first method developed produced an oxidized Cu surface. A distinct spectral shift of the bands characteristic of the adsorbate was observed, due to its interaction with Cu2O instead of interacting with metallic Cu. The second method produced a substrate with a clean surface and large specific surface area which resulted in a high quality SERS spectrum exhibiting a 10-fold increase in the signal-to-noise ratio, compared to the results for the surface pretreated by commonly used methods of surface roughening (oxidation-reduction cycling). The third method included an irreversible, diffusion-controlled Cu deposition onto a substrate and resulted in a rather complex, partially oxidized substrate with Cu clusters exhibiting a variety of SERS activities. The second method appeared also useful for the modification of the surface activity of Cu-Zr amorphous alloys. This method was combined with an ageing process of the AA to produce a partial devitrification of the substrate. The electrochemical pretreatment was then applied after this partial devitrification. The catalytic efficiency for dehydrogenation of 2-propanol on such a pretreated Cu-Zr substrate increased by a factor of two. A correlation has been found between the SERS activity of an electrochemically pretreated substrate and its catalytic efficiency. A tentative mechanism of surface activation is discussed.

Original languageEnglish
Pages (from-to)227-234
Number of pages8
JournalMaterials Science and Engineering A
Volume267
Issue number2
Publication statusPublished - Jul 31 1999

Fingerprint

Amorphous alloys
Metals
metals
Substrates
Raman spectroscopy
Adsorbates
Chemical activation
activation
crystallization
2-Propanol
Propanol
Dehydrogenation
Specific surface area
Surface properties
dehydrogenation
Signal to noise ratio
Dissolution
pretreatment
Aging of materials
dissolving

Keywords

  • Adsorption
  • Catalytic activity
  • Cu metal
  • Cu-Zr amorphous alloys
  • Dissolution/redeposition
  • SERS activity
  • Surface activation

ASJC Scopus subject areas

  • Materials Science(all)

Cite this

Janik-Czachor, M., Kudelski, A., Dolata, M., Varga, M., Szummer, A., Bukowska, J., & Molnár, Á. (1999). Modification of surface activity of Cu-Zr amorphous alloys and Cu metal by electrochemical methods. Materials Science and Engineering A, 267(2), 227-234.

Modification of surface activity of Cu-Zr amorphous alloys and Cu metal by electrochemical methods. / Janik-Czachor, M.; Kudelski, A.; Dolata, M.; Varga, M.; Szummer, A.; Bukowska, J.; Molnár, Á.

In: Materials Science and Engineering A, Vol. 267, No. 2, 31.07.1999, p. 227-234.

Research output: Contribution to journalArticle

Janik-Czachor, M, Kudelski, A, Dolata, M, Varga, M, Szummer, A, Bukowska, J & Molnár, Á 1999, 'Modification of surface activity of Cu-Zr amorphous alloys and Cu metal by electrochemical methods', Materials Science and Engineering A, vol. 267, no. 2, pp. 227-234.
Janik-Czachor M, Kudelski A, Dolata M, Varga M, Szummer A, Bukowska J et al. Modification of surface activity of Cu-Zr amorphous alloys and Cu metal by electrochemical methods. Materials Science and Engineering A. 1999 Jul 31;267(2):227-234.
Janik-Czachor, M. ; Kudelski, A. ; Dolata, M. ; Varga, M. ; Szummer, A. ; Bukowska, J. ; Molnár, Á. / Modification of surface activity of Cu-Zr amorphous alloys and Cu metal by electrochemical methods. In: Materials Science and Engineering A. 1999 ; Vol. 267, No. 2. pp. 227-234.
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