From introduction: The aim of this special issue is to show, through recent updated significant examples, how the electrochemical techniques allow the unique characterization of specific properties of micro- and nanostructured materials that offer varied possibilities of uses and the preparation of specific types of ordered materials that take advantage of electrochemical synthetic methods such as structuring nanosized wires and dots, to cite only two examples

Bedioui, Fethi

Nyokong, Tebello

Zagal, Jose H

International Journal of Electrochemistry

Fethi Bedioui

Tebello Nyokong

José H. Zagal

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Surface Electrochemistry: Structured Electrode, Synthesis, and Characterization

Bedioui, F.

Nyokong, T.

Zagal, J.H.

SEALS Digital commons

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Hindawi Publishing CorporationInternational Journal of ElectrochemistryVolume 2012, Article ID 405825, 2 pagesdoi:10.1155/2012/405825EditorialSurface Electrochemistry: Structured Electrode, Synthesis,and CharacterizationFethi Bedioui,1 Tebello Nyokong,2 and José H. Zagal31 Unité de Pharmacologie Chimique et Génétique et Imagerie, UMR CNRS 8151-U INSERM 1022,Chimie ParisTech and Université Paris Descartes, 11 rue Pierre et Marie Curie, 75231 Paris, France2 Department of Chemistry, Rhodes University, Grahamstown 6140, South Africa3 Departamento de Quı́mica de los Materiales, Facultad de Quı́mica y Bioloǵıa, Universidad de Santiago de Chile, Casilla 40,Sucursal Matucana, Santiago 9170022, ChileCorrespondence should be addressed to Fethi Bedioui, fethi-bedioui@chimie-paristech.frReceived 1 December 2011; Accepted 1 December 2011Copyright © 2012 Fethi Bedioui et al. This is an open access article distributed under the Creative Commons Attribution License,which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Electrochemistry has become a multidisciplinary science,and a growing emphasis in the last decades has been focusedon the chemical control of the structure of the electrode/solution interface in order to achieve desired reactivity forelectron transfer processes involving target molecules. Thus,modified electrode surfaces have become a wide topic thatcovers several issues of interfacial electrochemistry, nano-technology, material science, sensors for biology and envi-ronmental sciences, and so forth.The aim of this special issue is to show, through recentupdated significant examples, how the electrochemical tech-niques allow the unique characterization of specific proper-ties of micro- and nanostructured materials that offer variedpossibilities of uses and the preparation of specific typesof ordered materials that take advantage of electrochemicalsynthetic methods such as structuring nanosized wires anddots, to cite only two examples.Five original research articles are presented in this issueand illustrate some of the efforts in developing electro-chemical strategies related to structured surfaces. Threethemes are concerned: electrochemical analysis of electrodesurfaces upon specific chemical treatments, electrochemicaldeposition of structured metal deposits and electrochemicalcharacterization of polymer-coated electrodes. In the paperentitled “Surface of alumina films after prolonged break-downs in galvanostatic anodization” by C. Girginov and S.Kozhukharov, the authors investigated the breakdown phe-nomena at continuous isothermal (20◦C) and galvanostatic(0.2–5 mA cm−2) anodizing of aluminum in ammoniumsalicylate in dimethylformamide (1 M AS/DMF) electrolyte.Data on topography and surface roughness parameters of theelectrode after electric breakdowns are obtained as a functionof anodization time. The results are discussed on the basisof perceptions of avalanche mechanism of the breakdownphenomena, due to the injection of electrons and their multi-plication in the volume of the film.In the paper entitled “Surface potential of polycrystalinehematite in aqueous medium” by T. Preočanin et al., the sur-face potential of polycrystalline hematite in aqueous sodiumperchlorate environment as a function of pH was examined.Surface potential of hematite was obtained from measuredelectrode potential of a nonporous polycrystalline hematiteelectrode, and interpretation of the equilibrium data wasperformed by applying the surface complexation model.In the paper entitled “Zinc-nickel codeposition in sulfatesolution combined effect of cadmium and boric acid” by Y.Addia and A. Khouider, the combined effect of cadmiumand boric acid on the electrodeposition of zinc-nickel froma sulfate has been investigated. It is shown that the pres-ence of cadmium ion decreases zinc in the deposit. Lowconcentration of CdSO4 reduces the anomalous nature ofZn-Ni deposit while boric acid decreases current density andshifts potential discharge of nickel and hydrogen to morenegative potential.In the paper entitled “Size and shape control of gold nan-odeposits in an array of silica nanowells on a gold electrode”by A. E. Rue and M. M. Collinson, ordered arrays of hemi-spherical nanowells were formed in a sol-gel derived silicafilm on a gold electrode using 500 nm diameter polystyrenelatex spheres as templates. The conductive domain located2 International Journal of Electrochemistryat the bottom of each nanowell upon template removalwas enlarged via electroless deposition from a gold platingsolution. The structured electrodes thus formed were char-acterized using scanning electron microscopy and atomicforce microscopy. Electroless deposition in the nanowellsproduced (near) sphere-like nanostructures of gold, thesize of which depended on the incubation time in theplating solution and the size of the conductive domain.Longer exposure times yielded nanostructures that filledthe nanowell whereas smaller exposure time yielded muchsmaller structures. Significantly larger, rougher deposits wereformed in nanowells with large conductive domains. Theelectrochemical response observed at these electrodes wasstrongly dependent on the extent of long-range packing, thepresence of defect sites in the film and their relative spacing,and the redox species in solution.Finally, in the paper entitled “Cyclic voltammetry andimpedance spectroscopy behavior studies of polyterthio-phene modified electrode” by N. Maouche and B. Nessark,a study of the electrochemical behaviour of terthiophene andits corresponding polymer, which is obtained electrochemi-cally as a film by cyclic voltammetry (CV) on platinum elec-trode, is presented. The analysis focuses essentially on theeffect of two organic solvents acetonitrile and dichloro-methane on the electrochemical behaviour of the obtainedpolymer. The electrochemical behavior of this materialwas investigated by cyclic voltammetry and electrochemicalimpedance spectroscopy (EIS). The impedance plots showthe semicircle which is characteristic of charge transfer resis-tance at the electrode/polymer interface at high frequencyand the diffusion process at low frequency.Fethi BediouiTebello NyokongJosé H. Zagal

Surface electrochemistry : structured electrode, synthesis, and characterization

South East Academic Libraries System (SEALS)

Hindawi Publishing CorporationInternational Journal of ElectrochemistryVolume 2012, Article ID 405825, 2 pagesdoi:10.1155/2012/405825EditorialSurface Electrochemistry: Structured Electrode, Synthesis,and CharacterizationFethi Bedioui,1 Tebello Nyokong,2 and Jose´ H. Zagal31Unite´ de Pharmacologie Chimique et Ge´ne´tique et Imagerie, UMR CNRS 8151-U INSERM 1022,Chimie ParisTech and Universite´ Paris Descartes, 11 rue Pierre et Marie Curie, 75231 Paris, France2Department of Chemistry, Rhodes University, Grahamstown 6140, South Africa3Departamento de Quı´mica de los Materiales, Facultad de Quı´mica y Biolog´ıa, Universidad de Santiago de Chile, Casilla 40,Sucursal Matucana, Santiago 9170022, ChileCorrespondence should be addressed to Fethi Bedioui, fethi-bedioui@chimie-paristech.frReceived 1 December 2011; Accepted 1 December 2011Copyright © 2012 Fethi Bedioui et al. This is an open access article distributed under the Creative Commons Attribution License,which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Electrochemistry has become a multidisciplinary science,and a growing emphasis in the last decades has been focusedon the chemical control of the structure of the electrode/solution interface in order to achieve desired reactivity forelectron transfer processes involving target molecules. Thus,modified electrode surfaces have become a wide topic thatcovers several issues of interfacial electrochemistry, nano-technology, material science, sensors for biology and envi-ronmental sciences, and so forth.The aim of this special issue is to show, through recentupdated significant examples, how the electrochemical tech-niques allow the unique characterization of specific proper-ties of micro- and nanostructured materials that oﬀer variedpossibilities of uses and the preparation of specific typesof ordered materials that take advantage of electrochemicalsynthetic methods such as structuring nanosized wires anddots, to cite only two examples.Five original research articles are presented in this issueand illustrate some of the eﬀorts in developing electro-chemical strategies related to structured surfaces. Threethemes are concerned: electrochemical analysis of electrodesurfaces upon specific chemical treatments, electrochemicaldeposition of structured metal deposits and electrochemicalcharacterization of polymer-coated electrodes. In the paperentitled “Surface of alumina films after prolonged break-downs in galvanostatic anodization” by C. Girginov and S.Kozhukharov, the authors investigated the breakdown phe-nomena at continuous isothermal (20◦C) and galvanostatic(0.2–5mA cm−2) anodizing of aluminum in ammoniumsalicylate in dimethylformamide (1M AS/DMF) electrolyte.Data on topography and surface roughness parameters of theelectrode after electric breakdowns are obtained as a functionof anodization time. The results are discussed on the basisof perceptions of avalanche mechanism of the breakdownphenomena, due to the injection of electrons and their multi-plication in the volume of the film.In the paper entitled “Surface potential of polycrystalinehematite in aqueous medium” by T. Preocˇanin et al., the sur-face potential of polycrystalline hematite in aqueous sodiumperchlorate environment as a function of pH was examined.Surface potential of hematite was obtained from measuredelectrode potential of a nonporous polycrystalline hematiteelectrode, and interpretation of the equilibrium data wasperformed by applying the surface complexation model.In the paper entitled “Zinc-nickel codeposition in sulfatesolution combined eﬀect of cadmium and boric acid” by Y.Addia and A. Khouider, the combined eﬀect of cadmiumand boric acid on the electrodeposition of zinc-nickel froma sulfate has been investigated. It is shown that the pres-ence of cadmium ion decreases zinc in the deposit. Lowconcentration of CdSO4 reduces the anomalous nature ofZn-Ni deposit while boric acid decreases current density andshifts potential discharge of nickel and hydrogen to morenegative potential.In the paper entitled “Size and shape control of gold nan-odeposits in an array of silica nanowells on a gold electrode”by A. E. Rue and M. M. Collinson, ordered arrays of hemi-spherical nanowells were formed in a sol-gel derived silicafilm on a gold electrode using 500 nm diameter polystyrenelatex spheres as templates. The conductive domain located2 International Journal of Electrochemistryat the bottom of each nanowell upon template removalwas enlarged via electroless deposition from a gold platingsolution. The structured electrodes thus formed were char-acterized using scanning electron microscopy and atomicforce microscopy. Electroless deposition in the nanowellsproduced (near) sphere-like nanostructures of gold, thesize of which depended on the incubation time in theplating solution and the size of the conductive domain.Longer exposure times yielded nanostructures that filledthe nanowell whereas smaller exposure time yielded muchsmaller structures. Significantly larger, rougher deposits wereformed in nanowells with large conductive domains. Theelectrochemical response observed at these electrodes wasstrongly dependent on the extent of long-range packing, thepresence of defect sites in the film and their relative spacing,and the redox species in solution.Finally, in the paper entitled “Cyclic voltammetry andimpedance spectroscopy behavior studies of polyterthio-phene modified electrode” by N. Maouche and B. Nessark,a study of the electrochemical behaviour of terthiophene andits corresponding polymer, which is obtained electrochemi-cally as a film by cyclic voltammetry (CV) on platinum elec-trode, is presented. The analysis focuses essentially on theeﬀect of two organic solvents acetonitrile and dichloro-methane on the electrochemical behaviour of the obtainedpolymer. The electrochemical behavior of this materialwas investigated by cyclic voltammetry and electrochemicalimpedance spectroscopy (EIS). The impedance plots showthe semicircle which is characteristic of charge transfer resis-tance at the electrode/polymer interface at high frequencyand the diﬀusion process at low frequency.Fethi BediouiTebello NyokongJose´ H. Zagal

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Surface electrochemistry : structured electrode, synthesis, and characterization

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