Electrochemistry/near-field microscopy couplings

In order to enrich and complete its capabilities for local electrochemical characterization of electrochemical reactivity, and to further enhance its role in the development of nanosciences, electrochemistry very quickly had to call upon, or even join forces with, high-performance surface analysis techniques enabling, if possible simultaneously, local in situ physico-chemical analysis, with optimum spatial resolution, of electrochemical interfaces of the conductor/solution type, and more generally solid/solution. It should be noted that these different requirements have often led to the exclusion of electron microscopies, sometimes because of their lack of resolution, and sometimes because they operate in a primary vacuum. It is against this backdrop that so-called "probe scanning" techniques have gradually become indispensable in the study of interfacial electrochemical processes, initially on the micrometric scale, then, in a second phase, on the nanometric or even atomic scale.

Considerable effort has gone into bringing electrochemistry into line with the two scanning probe techniques (SPM) that are only slightly older than SECM: scanning tunnelling microscopy (STM) and atomic force microscopy (AFM). The aim was to show how these two techniques have boosted electrochemistry's contribution to nanoscience tenfold, by providing the means to generate, modify and, above all, characterize nanostructured or nanofunctionalized electrochemical interfaces and electrogenerated nano-objects, not globally but very locally, with nanometric or even atomic resolution, depending on the working conditions and technique used. The characterizations thus made accessible are then physical, and more specifically, morphological, mechanical, electrical or even physico-chemical (surface forces) depending on the technique and its operating mode used.

This chapter provides a detailed introduction to AFM/electrochemistry and STM/electrochemistry couplings and their most advanced applications.