The first stage of the analysis is implemented in real time during the potential scan and gives variable impedance spectra (in the right part of the screen) and a characteristic 3D surface (PDEIS spectrum), which shows dependences of active and reactive parts of the impedance on the ac frequency and the electrode potential. The dc part of the response is decomposed at this stage and also appears in the PDEIS spectrum, in the form similar to a common cyclic voltammogram. The ac part of the PDEIS spectrum is the multi-frequency analogue of an ac voltammogram. Unlike the common ac voltammogram, PDEIS spectrum contains information on the frequency response, and this allows taking the next step in the analysis of potentiodynamic responses.
Click the 3D spectrum to see higher resolution image and animation.
Genady Ragoisha, 2004 Physico-Chemical Research Institute Belarusian State University |