Ac-Electrogravimetry Study of Electroactive Thin Films. I. Application to Prussian Blue

Abstract

Prussian Blue films were investigated by using ac-electrogravimetry, that is, simultaneous impedance and electrogravimetry spectroscopies at different potentials between the totally reduced form, Everitt's salt, and the mixed-valence compound, Prussian Blue, in KCl solutions. Experimental results allow clear information on the role played by the different ions that are present in the solution to be obtained. It was found that when the film was reduced potassium ions enter the film whereas these are protons that enter at potentials more anodic than the formal potential of the redox process in KCl solutions. It was also proved that potassium ions enter the PB film without water.

Electrochemically induced free solvent transfer in thin poly(3,4-ethylenedioxythiophene) films

“…As it was demonstrated earlier [33,34], species kinetics in thin films depend on their resistance to cross the polymer|solution interface:…”

Identification of electroactive sites in Prussian Yellow films

“…For this purpose electrogravimetric techniques seem the best choice. During the last few years, the development of ac-electrogravimetry techniques (mass impedance) has allowed to identify in a fast way the participation of cations or anions during the electrochemical processes by only looking at the quadrant on which the impedance loop appears [32,[46][47][48]. Basically, a loop on the 1 st quadrant on the mass impedance plot indicates the participation of anions during electrochemical processes, but a loop on the 3 rd quadrant…”

Gravimetric and dynamic deconvolution of global EQCM response of carbon nanotube based electrodes by Ac-electrogravimetry

“…Here, an alternative characterization tool was proposed which couples fast quartz crystal microbalance (QCM) and electrochemical impedance spectroscopy (EIS) (also called acelectrogravimetry) [12][13][14][15]. It was employed to characterize supercapacitive charge storage mechanism of single wall carbon nanotube (SWCNT) based electrodes revealing the unique sensitivity of the ac-electrogravimetry to provide gravimetric and dynamic deconvolution of a global EQCM response.…”