Electrochemical determination of nitroaromatic explosives at boron-doped diamond/graphene nanowall electrodes: 2,4,6-trinitrotoluene and 2,4,6-trinitroanisole in liquid effluents
Abstract
The study is devoted to the electrochemical detection of trace explosives on boron-doped diamond/graphene nanowall electrodes (B:DGNW). The electrodes were fabricated in a one-step growth process using chemical vapour deposition without any additional modifications. The electrochemical investigations were focused on the determination of the important nitroaromatic explosive compounds, 2,4,6-trinitrotoluene (TNT) and 2,4,6-trinitroanisole (TNA). The distinct reduction peaks of both studied compounds were observed regardless of the pH value of the solution. The reduction peak currents were linearly related to the concentration of TNT and TNA in the range from 0.05–15 ppm. Nevertheless, two various linear trends were observed, attributed respectively to the adsorption processes at low concentrations up to the diffusional character of detection for larger contamination levels. The limit of detection of TNT and TNA is equal to 73 ppb and 270 ppb, respectively. Moreover, the proposed detection strategy has been applied under real conditions with a significant concentration of interfering compounds – in landfill leachates. The proposed bare B:DGNW electrodes were revealed to have a high electroactive area towards the voltammetric determination of various nitroaromatic compounds with a high rate of repeatability, thus appearing to be an attractive nanocarbon surface for further applications.
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- Articles
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- artykuły w czasopismach
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JOURNAL OF HAZARDOUS MATERIALS
no. 387,
pages 1 - 9,
ISSN: 0304-3894 - Language:
- English
- Publication year:
- 2020
- Bibliographic description:
- Dettlaff A., Jakóbczyk P., Ficek M., Wilk B., Szala M., Wojtas J., Ossowski T., Bogdanowicz R.: Electrochemical determination of nitroaromatic explosives at boron-doped diamond/graphene nanowall electrodes: 2,4,6-trinitrotoluene and 2,4,6-trinitroanisole in liquid effluents// JOURNAL OF HAZARDOUS MATERIALS -Vol. 387, (2020), s.1-9
- DOI:
- Digital Object Identifier (open in new tab) 10.1016/j.jhazmat.2019.121672
- Bibliography: test
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- Sources of funding:
-
- Project DIAMSEC - ultrasensitive sensing platform for rapid detection of epidemiological and pandemic threats
- Project 2D phosphorene nanostructures - synthesis and analysis of opto-electrochemical properties towards biosensing systems
- Statutory activity/subsidy
- Science for Peace Programme of NATO [Grant no. G5147]
- Verified by:
- Gdańsk University of Technology
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