Abstract
A rotating disc gold electrode, either bare or modified with an alkanethiol self-assembled monolayer, was used to measure the simultaneous square wave voltammetric differential current response of the electrochemical reduction of the two ordnance-related compounds (ORCs) 2,4,6-trinitrotoluene (TNT) and 2,4-dinitrotoluene (DNT). On bare electrodes, background currents limited sensitivity to ppm levels. In order to suppress these interfering currents, the gold electrodes were modified with alkanethiols of various chain lengths, from 3 to 12 carbons, with hydrophilic (hydroxyl) or hydrophobic (methyl) end groups presented to the electrolyte. Gold electrodes endowed with hydroxyl-terminated monolayers enabled clear detection of TNT and DNT from mixtures of these two compounds. In addition, longer alkanethiols allowed extension of the working potential range to more negative values than achieved with shorter alkanethiols.
Original language | English (US) |
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Pages (from-to) | 509-515 |
Number of pages | 7 |
Journal | Sensors and Actuators, B: Chemical |
Volume | 133 |
Issue number | 2 |
DOIs | |
State | Published - Aug 12 2008 |
Keywords
- 2,4,6-Trinitrotoluene
- 2,4-Dinitrotoluene
- Alkanethiol self-assembled monolayers
- Square wave voltammetry
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Instrumentation
- Condensed Matter Physics
- Surfaces, Coatings and Films
- Metals and Alloys
- Electrical and Electronic Engineering
- Materials Chemistry