Local electrochemical impedance spectroscopy: A window into heterogeneous interfaces

Abstract

The ability to probe surface reactivity on a local scale has led to new insight on the comprehension of the electrochemical reactivity in relation with the microstructure of the surface. Among the different techniques developed in recent years, local electrochemical impedance spectroscopy has the advantage of using a transient approach to locally characterize a stationary electrochemical system without the need to add any redox mediator in solution, which is a great advantage for the study of different systems. In this review, particular attention is paid to the different ways of measuring the local impedance, and the technique implementing a local current measurement in solution is deeply discussed. This local electrochemical impedance spectroscopy journey also encompasses a discussion about technical and experimental limitations.

Electrochemical Impedance Measurements in Scanning Ion Conductance Microscopy

“…7 μm radius, compared to the tip radius of 100 nm. This discrepancy can originate from the displacement of the probe due to thermal drift at low frequencies or/and from the frequency dispersion of the electric field, as reported for local EIS-AFM measurements in the case of small counter electrodes , (vide infra).…”

“…Significant frequency dispersion can be detrimental for the quantification of the local properties of conductive interfaces . For impedance imaging, we thus used a single frequency (320 Hz), which was sufficiently low to be sensitive to the interfacial capacitance but high enough to speed up the analysis at each pixel to avoid thermal drift issues (SI, Figure S3).…”

“…This limitation was removed in local EIS measurements using atomic force microscopy (AFM) with a conductive tip as the counter electrode in a two-electrode mode. − Examples of local EIS-AFM measurements include characterization of the conductive channels of a Nafion membrane surface, intergranular corrosion of AISI 304 stainless steel, and oxygen reduction reaction kinetics at platinum/Nafion contacts . The use of a small counter electrode (i.e., AFM tip), however, complicates the quantitative analysis of impedance spectra because the electric field distribution depends strongly on the frequency of the applied harmonic bias. , …”

Electrochemical impedance spectroscopy

“…These techniques have also been used to evaluate other transfer functions involving electrochemical systems such as thermal impedance spectroscopy, 153 electrohydrodynamic impedance [154][155][156] , modulation of the interfacial capacitance 157-160 and local electrochemical impedance spectroscopy. [161][162][163][164][165] [H2] FIELD-SPECIFIC LIMITATIONS…”

Enhancing the Corrosion Protection of AA2024-T3 Alloy by Surface Treatments Based on Piperazine-Modified Hybrid Sol–Gel Films

“…Local electrochemical impedance mapping (LEIM) can give valuable information on the mechanism of corrosion on a controlled defect made on coated metal samples [49,67,68]. Previous studies have shown that for the correct detection of heterogeneities in solid/liquid interfaces by using local electrochemical impedance, it is necessary to select adequate input AC signal frequency and ranges of electrolyte conductivity [69,70].…”