Scanning electrochemical microscopy investigated

Zoski, C. G. Scanning electrochemical microscopy Investigation of hydrogen oxidation at polycrystal-hne noble metal electrodes. J. Phys. Chem. B 2003, 107, 6401—6405. 

Ciani, I., Burt, D. R, Daniele, S., Unwin, R R. Effect of surface pressure on oxygen transfer across molecular monolayers at the air/water interface Scanning electrochemical microscopy investigations using a mercury hemispherical microelectrode probe. J. Phys. Chem. B 2004, 108, 3801. 

Jensen, M. B., J. M. Karels, A. F. Guerard, and D. E. Tallman, Video microscopy and scanning electrochemical microscopy investigations of the mediated electrodeposition of polypyrrole on aluminum alloy AA 2024-T3, Electrochimica Acta, 2011 (Unpublished results, manuscript in preparation). 

Fonseca, S., Barker, A., Ahmed, S., Kemp, T., Unwin, P. Scanning electrochemical microscopy investigation of the photodegradation kinetics of 4-chlorophenol sensitized by TiOj films. Phys. Chem. Chem. Phys. 2004, 6, 5218-5224. 

A variety of other techniques have been used to investigate ion transport in conducting polymers. The concentrations of ions in the polymer or the solution phase have been monitored by a variety of in situ and ex situ techniques,8 such as radiotracer studies,188 X-ray photoelectron spectroscopy (XPS),189 potentiometry,154 and Rutherford backscatter-ing.190 The probe-beam deflection method, in which changes in the density of the solution close to the polymer surface are monitored, provides valuable data on transient ion transport.191 Rotating-disk voltammetry, using an electroactive probe ion, provides very direct and reliable data, but its utility is very limited.156,19 193 Scanning electrochemical microscopy has also been used.194... 

For the investigation of electrode reaction parameters and chemistry at these dimensions, another approach is necessary, in order to make the system species-selective through monitoring the electrochemistry. This involves making tip and substrate into independent electrodes the tip is thus a microelectrode. The microelectrode tip is scanned over the surface this is known as scanning electrochemical microscopy (SECM) [43] and due to its local probe nature can be used to probe microvolumes. 

The scanning electrochemical microscopy (SECM) technique introduced in recent years by Allen Bard is another area where the smallness of the electrode is essential [38]. The principle in SECM is a mobile UME inserted in an electrolyte solution. The UME is normally operated in a potentiostatic manner in an unstirred solution so that the current recorded is controlled solely by the spherical diffusion of the probed substance to the UME. The current can be quantified from Eqs. 48, 49, or 89 as long as the electrode is positioned far from other interfaces. However, if a solid body is present in the electrolyte solution, the diffusion of the substance to the UME is altered. For instance, when the position of the UME is lowered in the z direction, that is, towards the surface of the object, the diffusion will be partially blocked and the current decreases. By monitoring of the current while the electrode is moved in the x-y plane, the topology of the object can be graphed. The spatial resolution is about 0.25 pm. In one investigation carried out by Bard et al, the... 

Scanning tunnelling microscopy, scanning electrochemical microscopy, and AFM-surface potential measurements have also been used to investigate Nafion films. Scanning electrochemical microscopy reveals a domain-like structure containing circular features ca. 1-2 nm in diameter made up of a conductive center (presumed to be ion-rich regions) surrounded by a much less conductive zone. " Atomic force microscopy surface potential measurements detect features that were interpreted as ion channels in Nafion membranes. The size of the claimed ion channels was... 

Endres F, Freyland W (1998) Electrochemical scanning tunneling microscopy investigation of HOPG and silver electrodeposition on HOPG from the acid room temperature molten salt aluminium chloride - l-methyl-3-butylimidazolium chloride. J Phys Chem B 102 10229-10236... 

I Kapui, RE Gyurcsanyi, G Nagy, K Toth, M Area, E Area. Investigation of styrene-methacrylic acid block copolymer micelle doped polypyrrole films by scanning electrochemical microscopy. J Phys Chem B 102 9934-9939, 1998. 

Scanning Electrochemical Microscopy (SECM) Investigations of ECPs... 

Scanning electrochemical microscopy (SECM) is a scanning probe technique in which the probe is a disk ultramicroelectrode (typical radius in the 5 to 25 pm range) that scans the surface of the investigated sample facing it [157]. SECM measurements are carried out in... 

G. Wittstock, T. Asmus, and T. Wilhelm, Investigation of ion-bombarded conducting polymer films by scanning electrochemical microscopy (SECM). Fresenius J. Anal. Chem., 367, 346 (2000). 

N.J. Yang and C.G. Zoski, Polymer films on electrodes Investigation of ion transport at poly(3,4-ethylenedioxythiophene) films by scanning electrochemical microscopy. Langmuir, 22, 10338 (2006). 

It is not necessary to deal with these techniques in detail here, since there are several books and monographs on the subject. The fundamental theory and practice of electrochemical and spectroelectrochemical methods can be found in [1,2] and also in [3-5], where investigations of polymeric surface layers are emphasized. Excellent monographs on EQCM [6-9] and PBD [10] are also recommended for further studies. Infrared, Mdssbauer spectroscopy, ellipsometry, etc., are described in [I I], while electron spin resonance is discussed in [12], radiotracer in [13], scanning tunneling microscopy in [14], and scanning electrochemical microscopy in [15]. The fundamentals of electrochemical impedance spectroscopy are treated in [1,2,16] however, the different models elaborated for electrochemically active films and membranes can be found in various papers (see later), while the most important methods for analyzing impedance spectra, as reported before 1994, are well summarized in [3]. Nevertheless, the essential elements of these techniques are briefly discussed here, in order to help the reader to understand the experimental material presented in this book. 

Amphlett, J.L. and Denuault, G. (1998) Scanning electrochemical microscopy (SECM) an investigation of the effects of tip geometry on amperometric tip response. Jourtud of Physical Chemistry B, 102, 9946-9951. 

Dobrzeniecka A, Zeradjanin A, Masa J, Stroka J, GoralM, SchuhmannW, Kulesza PJ. Scanning electrochemical microscopy for investigation of multi-component bioelectrocatalytic films. ECS Trans 2011 35 33-44. 

Scanning Electrochemical Microscopy (SECM) (53) is an electroanalytical technique that has been used to smdy the kinetics of electron transfer in a variety of substrates (54-58). However, there are very few reports about its use in investigating the SEI (23, 59-64). A detailed description of SECM is given in Chapter 12. There are also many review articles that deal extensively with this technique (65-68). 

Cornut, R., A. Bhasin, S. Lhenry, M. Etienne, and C. Lefrou, Accurate and simplified consideration of the probe geometrical defaults in scanning electrochemical microscopy Theoretical and experimental investigations. Anal. Chem., Vol. 83, 2011 pp. 9669-9975. 

Kanoufi, R, C. Cannes, Y. B. Zu, and A. J. Bard, Scanning electrochemical microscopy. 43. Investigation of oxalate oxidation and electrogenerated chemiluminescence across the liquid-liquid interface, J Phys Chem B, Vol. 105, (2001) p. 8951. 

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