title: Interfacial behavior of sulforhodamine 101 at the polarized water/1,2-dichloroethane interface studied by spectroelectrochemical techniques.
abstract: The transfer mechanism of an amphoteric rhodamine, sulforhodamine 101 (SR101), across the polarized water/1,2-dichloroethane (DCE) interface was investigated using cyclic voltammetry, differential voltfluorometry and potential-modulated fluorescence (PMF) spectroscopy. The voltammetric response for the ion transfer of SR101 monoanion from water to DCE was observed as the diffusion-controlled transfer process. An unusual voltammetric response was found at 0.15 V more negative than the formal transfer potential of SR101(-) (deltaW(O)phi degrees') in the cyclic voltammogram and voltfluorogram. The frequency dependence of the PMF responses confirmed the presence of the adsorption processes at negative potentials. In addition, a further transient adsorption step was uncovered at deltaW(O)phi degrees'. The interfacial mechanism of SR101 is discussed by comparing the results obtained from each technique.
authors.affiliation: Department of Applied Chemistry, Faculty of Engineering, Nagasaki University, Bunkyo, Nagasaki, 852-8521, Japan. nagatani@nagasaki-u.ac.jp
authors.forename: Hirohisa
authors.initials: H
authors.lastname: Nagatani
authors.forename: Shingo
authors.initials: S
authors.lastname: Suzuki
authors.forename: David J
authors.initials: DJ
authors.lastname: Fermín
authors.forename: Hubert H
authors.initials: HH
authors.lastname: Girault
authors.forename: Kiyoharu
authors.initials: K
authors.lastname: Nakatani
mesh_terms: D004396:Coloring Agents / Q000737:chemistry; D004563:Electrochemistry; D005025:Ethylene Dichlorides / Q000737:chemistry*; D015394:Molecular Structure; D012235:Rhodamines / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013499:Surface Properties; D014867:Water / Q000737:chemistry
chemical_list: D004396:Coloring Agents; D005025:Ethylene Dichlorides; D012235:Rhodamines; D014867:Water; C024565:ethylene dichloride; C050829:sulforhodamine 101