Projects per year
Abstract
Bipotentiostatic control of micro-and nano-trench sensor systems provides new opportunities for enhancing signals (employing feedback currents) and for improved selectivity (by "chemical filtering"). In this study both phenomena are exploited with a gold-gold micro-trench electrode with ca. 70 μm width and ca. 800 μm trench depth. In "generator-collector mode", feedback current enhancement is demonstrated for the hydroquinone/benzoquinone redox system. Next, a "modulator-sensor mode" experiment is developed in which one electrode potential is stepped into the negative potential region (employing the normal pulse voltammetry method) to induce an oscillating pH change locally in the micro-trench. The resulting shift in the hydroquinone/benzoquinone reversible potential causes a Faradaic sensor signal (employing chronoamperometry). This method provides a "chemical filter" by selecting pH-sensitive redox processes only, and by showing enhanced sensitivity in the region of low buffer capacity. The results for the chemically reversible hydroquinone/benzoquinone system are contrasted to the detection of the chemically irreversible ammonia oxidation.
Original language | English |
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Pages (from-to) | 349-359 |
Number of pages | 11 |
Journal | Faraday Discussions |
Volume | 164 |
Early online date | 12 Mar 2013 |
DOIs | |
Publication status | Published - 1 Nov 2013 |
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Dive into the research topics of 'Pulse electroanalysis at gold-gold micro-trench electrodes: chemical signal filtering'. Together they form a unique fingerprint.Projects
- 1 Finished
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Nanogap Electrochemistry and Sensor Technology at the Molecular Limit
Marken, F. (PI)
Engineering and Physical Sciences Research Council
1/11/11 → 30/04/15
Project: Research council
Equipment
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MC2-Electron Microscopy (EM)
Material and Chemical Characterisation (MC2)Facility/equipment: Technology type