Surface reactivity imaging, scanning electrochemical microscopy

Under appropriate conditions, the faradaic current may be used to form images of the electrochemical reactivity of a surface. This is known as scanning electrochemical microscopy (SECM), where the transport and heterogeneous redox activity of species within the junction mediate the tip-substrate interaction. This subject has been thoroughly reviewed [43,44], and an excellent paper demonstrating the transition from STM to SECM is available [45]. The possible contribution of confined redox species to resonant tunneling has also been examined [19,46,47]. 

Scanning electrochemical cell microscopy (SECCM) also allows acquisition of high-resolution images of the reactivity of an electrode surface. 

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