Scanning electrochemical microscopy (SECM) is a scanning probe technique in which an ultramicroelectrode (UME) is poised in close proximity to another electrode’s surface to obtain information about its reactivity—such as through feedback of a redox mediator in solution between the UME and surface (Figure 1)—or to modify the surface. The UME is attached to highly sensitive motors that can adjust the distance of the UME from the surface or move it laterally to obtain an image of the topography and/or reactivity of the surface. Our SECM system from CH Instruments (Figure 2) is used to probe the activity of electrode surfaces, such as graphene and photocatalysts.Our group has also combined SECM capabilities with in situ mass spectrometry for characterizing electrocatalysts.
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