LAUSR

An important role of the electrochemical impedance spectroscopy (EIS) is the characterization of the electrical double layer formed at the electrode/electrolyte interfaces. The phenomenological double layer studies with an aqueous and ionic liquid electrolytes are reviewed with a conclusion that the double-layer capacitance is frequency dependent as the rule rather than the exception. We discuss the impedance consequences of the non-uniform current distribution along the electrochemical interface, which also contributes to the apparent frequency dependence of the capacitance. Finally, we show recent articles on non-conventional EIS techniques with high lateral resolution or enabling fast measurements.