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Electrochemical AFM (EC-AFM) is a particular type of Scanning probe microscopy (SPM), which combines the classical Atomic force microscopy (AFM) together with electrochemical measurements. EC-AFM allows to perform in-situ AFM measurements in an electrochemical cell, in order to investigate the actual changes in the electrode surface morphology during electrochemical reactions. The solid-liquid interface is thus investigated. This technique was developed for the first time in 1996 by Kouzeki et al., who studied amorphous and polycrystalline thin films of Naphthalocyanine on Indium tin oxide in a solution of 0.1 M Potassium chloride (KCl). Unlike the Electrochemical scanning tunneling microscope, previously developed by Itaya and Tomita in 1988, the tip is non-conductive and it is easily steered in a liquid environment.
Raman spectroelectrochemistry (Raman-SEC) is a technique that studies the inelastic scattering or Raman scattering of monochromatic light related to chemical compounds involved in an electrode process. This technique provides information about vibrational energy transitions of molecules, using a monochromatic light source, usually from a laser that belongs to the UV, Vis or NIR region. Raman spectroelectrochemistry provides specific information about structural changes, composition and orientation of the molecules on the electrode surface involved in an electrochemical reaction, being the Raman spectra registered a real fingerprint of the compounds.
References
- ↑ Liu, H.Y.; Fan, F.-R.F; Lin, C.W.; Bard, A.J. (1986). "Scanning electrochemical and tunneling ultramicroelectrode microscope for high-resolution examination of electrode surfaces in solution". J. Am. Chem. Soc. 108: 3838.
- ↑ Itaya, Kingo; Tomita, Eisuke (1988). "Scanning tunneling microscope for electrochemistry - a new concept for the in situ scanning tunneling microscope in electrolyte solutions". Surface Science. 201 (3): L507–L512. Bibcode:1988SurSc.201L.507I. doi:10.1016/0039-6028(88)90489-X. ISSN 0039-6028.
- ↑ Allen J. Bard; Michael V. Mirkin (16 April 2012). Scanning Electrochemical Microscopy, Second Edition. CRC Press. pp. 1–. ISBN 978-1-4398-3112-0.
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