Local electrochemical impedance spectroscopy: A review and some recent developments

Abstract

a b s t r a c tLocal electrochemical impedance spectroscopy (LEIS), which provides a powerful tool for exploration of electrode heterogeneity, has its roots in the development of electrochemical techniques employing scanning of microelectrodes. The historical development of local impedance spectroscopy measurements is reviewed, and guidelines are presented for implementation of LEIS. The factors which control the limiting spatial resolution of the technique are identified. The mathematical foundation for the technique is reviewed, including definitions of interfacial and local Ohmic impedances on both local and global scales. Experimental results for the reduction of ferricyanide show the correspondence between local and global impedances. Simulations for a single Faradaic reaction on a disk electrode embedded in an insulator are used to show that the Ohmic contribution, traditionally considered to be a real value, can have complex character in certain frequency ranges.

Galvanic corrosion between zinc and carbon steel investigated by local electrochemical impedance spectroscopy

“…[22,25,[28][29][30]. This technique is based on the pioneering work of Isaac's group [25,28] and takes into account the recent developments to improve the measurements and interpretation of experimental results [22,29,30].…”

Effect of conductivity and frequency on detection of heterogeneities in solid/liquid interfaces using local electrochemical impedance

“…It is important to note that although this limitation is known and reported in most of the works associated with localized electrochemical techniques [17][18][19][20][21], whose theoretical principles are based on the potential gradients in the electrolyte, it is also true that no work refers to the fact that the effect of the conductivity is not the same around an irregularity with constant potential as around an active irregularity.…”

“…k being the electrolyte conductivity, d the distance between the tip and the ring in the special bi-electrode and ∆V the potential difference in the electrolyte between the surroundings of both the ring and the tip [17][18][19][20][21].…”

Influence of hydrogen-oxidizing bacteria on the corrosion of low carbon steel: Local electrochemical investigations

“…Similarly to the SECM, LEIS consisted in using a micro probe for measuring the local current density [21,[37][38][39]. The two devices require some similar apparatus, in particular for positioning the probe in the vicinity of the substrate.…”

“…The local impedance (z) involves the electrode potential measured with respect to a reference electrode located far from the electrode surface and the local current according to [38][39][40]:…”