Integrated electrochemical-atomic force

High-Resolution Dissolution Imaging with Integrated Electrochemical-Atomic Force Microscopy... 

Jones, C. E., Macpherson, J. V., Unwin, P. R. In-situ observation of the surface processes involved in dissolution from the (010) surface of potassium ferrocyanide trihydrate in aqueous solution using an integrated electrochemical-atomic force microscope. J. Phys. Chem. B 2000,104, 2351. 

A highly significant recent development is the integration of atomic force microscopy with SECM (AFM-SECM) [220]. Further details are described in Chapter 3.2 of this volume. An etched Pt wire was flattened and then insulated with electrophoretic paint. This probe acts as the cantilever in AFM and as the SECM tip providing dual force-sensing and electrochemical capabilities. Submicron resolution for SECM and for topography by AEM was achieved for test samples of track-etched polycarbonate membranes and ionic crystal surfaces. As the resolution of the technique improves and it is combined with other scanning probes, it seems likely that SECM can be applied in an ever-wider spectrum of scientific fields. 

Sklyar, O., Kueng, A., Kranz, C. et al. (2005) Numerical simulation of scanning electrochemical microscopy experiments with frame-shaped integrated atomic force microscopy-SECM probes using the boundary element method. Analytical Chemistry, 77, 764-771. 

Modified electrodes can be characterized by electrochemical methods, spectroscopic methods (such as X-ray photoelectron spectroscopy), and microscopy methods (such as atomic force microscopy and scanning electron microscopy). These techniques when combined give a good idea of the effectiveness of the modification, the properties of the layer and the integrity of the surface coverage. A description of a selection of characterization techniques follows. 

Atomic force microscopy (AFM) was the principal technique u.sed to visualize structural changes occurring on the surfaces of A and B as a result of the above electrochemical experiments. A Topometrix Explorer AFM was employed, with a probe having an integral standard pyramidal tip. A relatively low force constant was used to avoid damage to the soft" surface film. Figures 16a-g show a scries of images obtained for A" and B alloys which had been polished initially to a mirror finish and were treated electrochemically as de.scribed above. Surfaces were analyzed in air immediately after their removal from solution. 

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