The working principle of the ElProScan |
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| The ElProScan is an electrochemical probe scanner related to the familiar scanning tunneling and atomic force microscopes. ElProScan allows observation and influence of very local electrochemical reactions, therefore, it is an excellent instrument for surface characterization and modification with high flexibility. In the Electrochemical Probe Scanner an ultramicroelectrode (=UME) or nanode is scanned in a liquid electrolyte closely above the surface of a sample. The reaction of redoxactive dissolved species at the UME results in a Faradaic current. When the UME is far away from the surface in the bulk solution the current is driven by the hemispherical diffusion of redoxactive species from the bulk solution to the surface of the UME. |
When the tip is approached near the surface of a substrate, a change in the measured current
can be observed. An electrochemical inert surface inhibits the diffusion of redoxactive substance
to the tip surface resulting in the measurement of a reduced tip current (Negative Feedback
current).
The current is increased by an electrochemically active surface, because some of the reacted redoxspecies regenerates at the electro-chemically active surface and can again react at the tip (Positive Feedback). price list | manual | brochure | home |