Untersuchung von Widerstandsänderungen polykristalliner Dünnschichtelektroden bei Schwermetallabscheidungen
Untersuchung von Widerstandsänderungen polykristalliner Dünnschichtelektroden bei Schwermetallabscheidungen
The lateral resistance of a thin metal film depends an the presence or absente of other species at the film surface. This phenomenon has been investigated regarding possible analytical applications for the determination of heavy metals in aqueous solutions. Microstructured polycrystalline noble meta...
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Personal Name(s): | Glück, O. (Corresponding author) |
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Contributing Institute: |
Publikationen vor 2000; PRE-2000; Retrocat |
Imprint: |
Jülich
Forschungszentrum Jülich, Zentralbibliothek, Verlag
1999
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Physical Description: |
IV, 125 p. |
Document Type: |
Report Book |
Research Program: |
ohne Topic |
Series Title: |
Berichte des Forschungszentrums Jülich
3713 |
Link: |
OpenAccess OpenAccess |
Publikationsportal JuSER |
The lateral resistance of a thin metal film depends an the presence or absente of other species at the film surface. This phenomenon has been investigated regarding possible analytical applications for the determination of heavy metals in aqueous solutions. Microstructured polycrystalline noble metal electrodes (film thickness $\sim$ 20 nm) were fabricated by silicon planar technology and their resistance-potential behavior was recorded during the electrochemical deposition and dissolution of selected heavy metals (Cd, Pb, Ni, Tl, Zn). The deposition causes an increase of the lateral electrode resistance. During the subsequent dissolution of the deposited heavy metal species the resistance decreases to its initial value. The magnitude of the resistance change depends linearly an the heavy metal content of the solution over a wide concentration range from a few ppb ($\mu$g/l) to some ppm (mg/l). Corresponding to voltammetric methods, the resistance measurements show a species selectivity in the electrode potentials of thermodynamic equilibrium between the deposited, i.e. reduced, and the dissolved, i.e. oxidized, form of the species. Thus, different species can be identified and simultaneously determined. Corresponding results with Cd-EDTA containing solutions indicate that this can also occur for organically complexed heavy metal species. |