Oxidation of Several p-Phenylenediamines in Room Temperature Ionic Liquids: Estimation of Transport and Electrode Kinetic Parameters
The electrochemical oxidation of N,N,N‘,N‘-tetramethyl-p-phenylenediamine (TMPD) has been studied by cyclic voltammetry and potential step chronoamperometry at 303 K in five ionic liquids, namely [C2mim][NTf2], [C4mim][NTf2], [C4mpyrr][NTf2], [C4mim][BF4], and [C4mim][PF6] (where [Cnmim]+ = 1-alkyl-...
| Main Authors: | , , , , , , |
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| Format: | Journal Article |
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American Chemical Society
2008
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| Online Access: | http://hdl.handle.net/20.500.11937/43925 |
| _version_ | 1848756849373872128 |
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| author | Long, J. Silvester, Debbie Barnes, A. Rees, N. Aldous, L. Hardacre, C. Compton, R. |
| author_facet | Long, J. Silvester, Debbie Barnes, A. Rees, N. Aldous, L. Hardacre, C. Compton, R. |
| author_sort | Long, J. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | The electrochemical oxidation of N,N,N‘,N‘-tetramethyl-p-phenylenediamine (TMPD) has been studied by cyclic voltammetry and potential step chronoamperometry at 303 K in five ionic liquids, namely [C2mim][NTf2], [C4mim][NTf2], [C4mpyrr][NTf2], [C4mim][BF4], and [C4mim][PF6] (where [Cnmim]+ = 1-alkyl-3-methylimidazolium, [C4mpyrr]+ = N-butyl-N-methylpyrrolidinium, [NTf2]- = bis(trifluoromethylsulfonyl)imide, [BF4]- = tetrafluoroborate, and [PF6]- = hexafluorophosphate). Diffusion coefficients, D, of 4.87, 3.32, 2.05, 1.74, and 1.34 × 10-11 m2 s-1 and heterogeneous electron-transfer rate constants, k0, of 0.0109, 0.0103, 0.0079, 0.0066, and 0.0059 cm s-1 were calculated for TMPD in [C2mim][NTf2], [C4mim][NTf2], [C4mpyrr][NTf2], [C4mim][BF4], and [C4mim][PF6], respectively, at 303 K. The oxidation of TMPD in [C4mim][PF6] was also carried out at increasing temperatures from 303 to 343 K, with an activation energy for diffusion of 32.3 kJ mol-1. k0 was found to increase systematically with increasing temperature, and an activation energy of 31.4 kJ mol-1 was calculated. The study was extended to six other p-phenylene-diamines with alkyl/phenyl group substitutions. D and k0 values were calculated for these compounds in [C2mim][NTf2], and it was found that k0 showed no obvious relationship with the hydrodynamic radius, r. |
| first_indexed | 2025-11-14T09:18:44Z |
| format | Journal Article |
| id | curtin-20.500.11937-43925 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T09:18:44Z |
| publishDate | 2008 |
| publisher | American Chemical Society |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-439252017-09-13T13:42:27Z Oxidation of Several p-Phenylenediamines in Room Temperature Ionic Liquids: Estimation of Transport and Electrode Kinetic Parameters Long, J. Silvester, Debbie Barnes, A. Rees, N. Aldous, L. Hardacre, C. Compton, R. The electrochemical oxidation of N,N,N‘,N‘-tetramethyl-p-phenylenediamine (TMPD) has been studied by cyclic voltammetry and potential step chronoamperometry at 303 K in five ionic liquids, namely [C2mim][NTf2], [C4mim][NTf2], [C4mpyrr][NTf2], [C4mim][BF4], and [C4mim][PF6] (where [Cnmim]+ = 1-alkyl-3-methylimidazolium, [C4mpyrr]+ = N-butyl-N-methylpyrrolidinium, [NTf2]- = bis(trifluoromethylsulfonyl)imide, [BF4]- = tetrafluoroborate, and [PF6]- = hexafluorophosphate). Diffusion coefficients, D, of 4.87, 3.32, 2.05, 1.74, and 1.34 × 10-11 m2 s-1 and heterogeneous electron-transfer rate constants, k0, of 0.0109, 0.0103, 0.0079, 0.0066, and 0.0059 cm s-1 were calculated for TMPD in [C2mim][NTf2], [C4mim][NTf2], [C4mpyrr][NTf2], [C4mim][BF4], and [C4mim][PF6], respectively, at 303 K. The oxidation of TMPD in [C4mim][PF6] was also carried out at increasing temperatures from 303 to 343 K, with an activation energy for diffusion of 32.3 kJ mol-1. k0 was found to increase systematically with increasing temperature, and an activation energy of 31.4 kJ mol-1 was calculated. The study was extended to six other p-phenylene-diamines with alkyl/phenyl group substitutions. D and k0 values were calculated for these compounds in [C2mim][NTf2], and it was found that k0 showed no obvious relationship with the hydrodynamic radius, r. 2008 Journal Article http://hdl.handle.net/20.500.11937/43925 10.1021/jp800235t American Chemical Society restricted |
| spellingShingle | Long, J. Silvester, Debbie Barnes, A. Rees, N. Aldous, L. Hardacre, C. Compton, R. Oxidation of Several p-Phenylenediamines in Room Temperature Ionic Liquids: Estimation of Transport and Electrode Kinetic Parameters |
| title | Oxidation of Several p-Phenylenediamines in Room Temperature Ionic Liquids: Estimation of Transport and Electrode Kinetic Parameters |
| title_full | Oxidation of Several p-Phenylenediamines in Room Temperature Ionic Liquids: Estimation of Transport and Electrode Kinetic Parameters |
| title_fullStr | Oxidation of Several p-Phenylenediamines in Room Temperature Ionic Liquids: Estimation of Transport and Electrode Kinetic Parameters |
| title_full_unstemmed | Oxidation of Several p-Phenylenediamines in Room Temperature Ionic Liquids: Estimation of Transport and Electrode Kinetic Parameters |
| title_short | Oxidation of Several p-Phenylenediamines in Room Temperature Ionic Liquids: Estimation of Transport and Electrode Kinetic Parameters |
| title_sort | oxidation of several p-phenylenediamines in room temperature ionic liquids: estimation of transport and electrode kinetic parameters |
| url | http://hdl.handle.net/20.500.11937/43925 |