Full metadata record
DC Field | Value | Language |
---|---|---|
dc.contributor.author | 박준우 | * |
dc.contributor.author | 이종목 | * |
dc.date.accessioned | 2016-08-28T11:08:40Z | - |
dc.date.available | 2016-08-28T11:08:40Z | - |
dc.date.issued | 2001 | * |
dc.identifier.issn | 0022-0728 | * |
dc.identifier.other | OAK-693 | * |
dc.identifier.uri | https://dspace.ewha.ac.kr/handle/2015.oak/218792 | - |
dc.description.abstract | The chemistry of the two-electron reduction product of viologen (1,1′-dialkyl-4,4′-bipyridinium, V2+) neutral species, is important in understanding the electrochemical behavior of viologens and their utilization. The kinetics for the reactions of neutral methyl viologen (V0) in the presence of H+ (from HCl), CH3COOH (pKa = 4.75), ClCH2CH2COOH (pKa = 4.00), HCOOH (pKa = 3.75) in aqueous media was examined by cyclic voltammetry according to the EECi mechanism. To avoid the electrodeposition of V0, we used a 9:1 (v/v%) H2O + DMF mixture as the solvent medium. To evaluate the rate constants for the chemical reaction followed by the second electron transfer step of V2+, the ratio of the anodic and cathodic peak current (Ipa2/Ipc2) corresponding to V0-e-⇄V·+ was plotted against log τ, where τ is the time between E1/2 and the switching potential, at various scan rates of 0.02-3.5 V s-1. The chemical reaction was found to be a parallel reaction consisting of H+-catalyzed and general-acid (HA) catalyzed reactions. The second-order rate constants are determined as kH+ = 3.5 × 103 M-1 s-1, kCH3COOH = 5.7 M-1 s-1, kHCOOH = 4.6 × 101 M-1 s-1, and kClCH2CH2COOH = 3.2 × 101 M-1 s-1 using the Nicholson-Shain method and kH2O was estimated as < 3 × 10-6 M-1 s-1. The CVs were digitally simulated under the assumption of a two-step reaction of V0 following the two-step electrode reactions of V2+ to V0. The simulated CVs show good agreement with those obtained experimentally, when the first-step reaction of V0 is a relatively fast reversible reaction and the second-step reaction is a slow irreversible one. Based on these results, we propose that V0 is in pseudo-equilibrium with H+ or HA to produce VH+ which undergoes a reaction with H2O. © 2001 Published by Elsevier Science B.V. | * |
dc.language | English | * |
dc.title | The kinetics of neutral methyl viologen in acidic H2O + DMF mixed solutions studied by cyclic voltammetry | * |
dc.type | Article | * |
dc.relation.issue | 1 | * |
dc.relation.volume | 504 | * |
dc.relation.index | SCOPUS | * |
dc.relation.startpage | 104 | * |
dc.relation.lastpage | 110 | * |
dc.relation.journaltitle | Journal of Electroanalytical Chemistry | * |
dc.identifier.doi | 10.1016/S0022-0728(01)00417-X | * |
dc.identifier.wosid | WOS:000168710800011 | * |
dc.identifier.scopusid | 2-s2.0-0035324650 | * |
dc.author.google | Ji Yoen Kim | * |
dc.author.google | Lee C. | * |
dc.author.google | Joon Woo Park | * |
dc.contributor.scopusid | 박준우(35332923800) | * |
dc.contributor.scopusid | 이종목(55812178500) | * |
dc.date.modifydate | 20240415121732 | * |