Electrochemical detection of explosive compounds in an ionic liquid in mixed environments: Influence of oxygen, moisture, and other nitroaromatics on the sensing response
From a security point of view, detecting and quantifying explosives in mixed environments is required to identify potentially concealed explosives. Electrochemistry offers a viable method to detect nitroaromatic explosive compounds owing to the presence of easily reducible nitro groups that give ris...
| Main Authors: | , |
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| Format: | Journal Article |
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CSIRO Publishing
2019
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| Online Access: | http://purl.org/au-research/grants/arc/FT170100315 http://hdl.handle.net/20.500.11937/74142 |
| _version_ | 1848763191821074432 |
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| author | Lee, Junqiao Silvester, Debbie |
| author_facet | Lee, Junqiao Silvester, Debbie |
| author_sort | Lee, Junqiao |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | From a security point of view, detecting and quantifying explosives in mixed environments is required to identify potentially concealed explosives. Electrochemistry offers a viable method to detect nitroaromatic explosive compounds owing to the presence of easily reducible nitro groups that give rise to a current signal. However, their reduction potentials can overlap with interfering species, making it difficult to distinguish particular compounds. We have therefore examined the effect of oxygen, moisture, and other nitroaromatic species on the cyclic voltammetry and square wave voltammetry of nitroaromatic compounds of a range of mixed environments, focussing on 2,4,6-trinitrotoluene (TNT) and 2,4-dinitrotoluene (DNT) as model analytes, and using the hydrophobic room-temperature ionic liquid (RTIL) [P14,6,6,6][NTf2] as the solvent. Oxygen (0-20 % vol.) minimally affected the current of the first reduction peak of TNT in [P14,6,6,6][NTf2], but significantly affects the current for DNT. The impact of water (0 to 86 % relative humidity), however, was much more dramatic-even in the hydrophobic RTIL, water significantly affected the currents of the analyte peaks for TNT and DNT, and gave rise to additional reduction features, further contributing to the current. Additionally, the voltammetry of other related di- and tri-nitro compounds (2,6-dinitrotoluene, 1,3-dinitrobenzene, 2,4,6-trinitrotoluene, 1,3,5-trinitrobenzene, and musk xylene) was also studied to understand how different substituents on the aromatic ring may affect the reduction potentials. A 50: 50 mixture of TNT and DNT revealed that both analytes could be separately identified and quantified using square wave voltammetry. Overall, this information is useful in determining the effect of other species on the current signals of electrochemical explosive sensors, and reveals that it may be necessary to dry the aprotic RTIL electrolyte when used in humid environments. |
| first_indexed | 2025-11-14T10:59:33Z |
| format | Journal Article |
| id | curtin-20.500.11937-74142 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T10:59:33Z |
| publishDate | 2019 |
| publisher | CSIRO Publishing |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-741422023-06-07T05:56:57Z Electrochemical detection of explosive compounds in an ionic liquid in mixed environments: Influence of oxygen, moisture, and other nitroaromatics on the sensing response Lee, Junqiao Silvester, Debbie From a security point of view, detecting and quantifying explosives in mixed environments is required to identify potentially concealed explosives. Electrochemistry offers a viable method to detect nitroaromatic explosive compounds owing to the presence of easily reducible nitro groups that give rise to a current signal. However, their reduction potentials can overlap with interfering species, making it difficult to distinguish particular compounds. We have therefore examined the effect of oxygen, moisture, and other nitroaromatic species on the cyclic voltammetry and square wave voltammetry of nitroaromatic compounds of a range of mixed environments, focussing on 2,4,6-trinitrotoluene (TNT) and 2,4-dinitrotoluene (DNT) as model analytes, and using the hydrophobic room-temperature ionic liquid (RTIL) [P14,6,6,6][NTf2] as the solvent. Oxygen (0-20 % vol.) minimally affected the current of the first reduction peak of TNT in [P14,6,6,6][NTf2], but significantly affects the current for DNT. The impact of water (0 to 86 % relative humidity), however, was much more dramatic-even in the hydrophobic RTIL, water significantly affected the currents of the analyte peaks for TNT and DNT, and gave rise to additional reduction features, further contributing to the current. Additionally, the voltammetry of other related di- and tri-nitro compounds (2,6-dinitrotoluene, 1,3-dinitrobenzene, 2,4,6-trinitrotoluene, 1,3,5-trinitrobenzene, and musk xylene) was also studied to understand how different substituents on the aromatic ring may affect the reduction potentials. A 50: 50 mixture of TNT and DNT revealed that both analytes could be separately identified and quantified using square wave voltammetry. Overall, this information is useful in determining the effect of other species on the current signals of electrochemical explosive sensors, and reveals that it may be necessary to dry the aprotic RTIL electrolyte when used in humid environments. 2019 Journal Article http://hdl.handle.net/20.500.11937/74142 10.1071/CH18396 http://purl.org/au-research/grants/arc/FT170100315 CSIRO Publishing fulltext |
| spellingShingle | Lee, Junqiao Silvester, Debbie Electrochemical detection of explosive compounds in an ionic liquid in mixed environments: Influence of oxygen, moisture, and other nitroaromatics on the sensing response |
| title | Electrochemical detection of explosive compounds in an ionic liquid in mixed environments: Influence of oxygen, moisture, and other nitroaromatics on the sensing response |
| title_full | Electrochemical detection of explosive compounds in an ionic liquid in mixed environments: Influence of oxygen, moisture, and other nitroaromatics on the sensing response |
| title_fullStr | Electrochemical detection of explosive compounds in an ionic liquid in mixed environments: Influence of oxygen, moisture, and other nitroaromatics on the sensing response |
| title_full_unstemmed | Electrochemical detection of explosive compounds in an ionic liquid in mixed environments: Influence of oxygen, moisture, and other nitroaromatics on the sensing response |
| title_short | Electrochemical detection of explosive compounds in an ionic liquid in mixed environments: Influence of oxygen, moisture, and other nitroaromatics on the sensing response |
| title_sort | electrochemical detection of explosive compounds in an ionic liquid in mixed environments: influence of oxygen, moisture, and other nitroaromatics on the sensing response |
| url | http://purl.org/au-research/grants/arc/FT170100315 http://hdl.handle.net/20.500.11937/74142 |