Alternative or Simultaneous Electrochemical Access with Micro Water/Oil Phases in a Middle Phase Microemulsion Based on the Hydrophilic/Lipophilic Balance on Electrode Surfaces

Abstract

The electrochemical contact with the micro aqueous phase and the micro organic solvent phase in the “middle phase” microemulsion, in which the water phase and the oil phase bicontinuously coexist on a microscopic scale, was alternatively or simultaneously achieved by controlling the hydrophilicity and lipophilicity on electrode surfaces.

The Formation of Middle‐Phase Microemulsions of Polar Oils

“…[17][18][19][20] To do this, it is important to precisely understand the phase behavior of the water/oil/surfactant system, as well as understand the selforganizing interfacial structure at the molecular level. By deepening our understanding, further development of the present field can be expected.…”

Mesostructured Polymer Materials Based on Bicontinuous Microemulsions

“…Schematic representation of BME solution structures at solid/oil/saline interfaces (a) and typical cyclic voltammograms measured using ITO (b), polished Au disk (c), polished GC (d), and cleaved HOPG (e) electrodes in BME in the presence of K 3 Fe(CN) 6 and ferrocene. 41 The amphiphilic electrode (Au) revealed redox peak couples for both K 3 Fe(CN) 6 and ferrocene in BME solutions simultaneously. 45 In contrast, strong hydrophilic or lipophilic electrodes (ITO and HOPG) produced only one of the peak couples of K 3 Fe(CN) 6 or ferrocene, depending on the affinities for the detecting electrodes.…”

“…The electrochemical contact with the micro aqueous and organic solution phases in a BME is alternately or simultaneously achieved by controlling the hydrophilicity and lipophilicity of the electrode surfaces. 45,46 Fig. 5.…”

“…Two factors are expected to influence formation of an LC phase from a BME during polymerization. A hydrophilic silica surface tends to trap water near the surface, 45,46 and the decrease in the water content of the ME causes enrichment of surfactants in the ME. The shift of the HLB of the surfactants resulting from the changes in the oil phase of the ME during polymerization, and hence changes in the monomer/polymer ratio and the degree of polymerization, might induce a phase change from a BME phase to an LC phase.…”

Middle Phase Electrochemistry of Two Pentacyano(L)Ferrates(II)

“…In this case the electrochemistry of a particular cyanoferrate may be studied even in the "middle phase", even if this "middle phase" is highly dynamic and even if the surface of the working electrode is, simultaneously in time but alternatively in space, in direct contact with the "organic film" and with "aqueous film" (which constitutes the "middle phase") in a statistical fashion and dynamic way. 10 The electroactive species is chosen in order to have a simple, reversible electrochemistry, high solubility in water and low solubility in toluene (the electroactive species being very hydrophilic) or, on the contrary, low solubility in water and high solubility in toluene (the electroactive species being very lipophilic). In addition, both redox forms are sufficiently soluble in water in contrast with other redox couples in which electroactive species can be oil soluble or both in water and organic phases.…”