Faradaic and capacitive current estimation by means of Independent Components Analysis and 1kHz sampling

Publication date: 1 August 2017
Source:Talanta, Volume 170
Author(s): Filip Ciepiela, Małgorzata Jakubowska
In this work it was demonstrated for the first time that Independent Components Analysis non-deterministic multivariate strategy enables estimation of the Faradic and double layer charging current components in differential pulse and anodic stripping voltammetry. The signals separation can be realized based on the different shapes of the capacitive and Faradaic current functions. The set of calibration voltammograms measured with the 1kHz sampling frequency is the sufficient data to retrieve signals compatible with the theoretical shapes, with r² greater than 0.987 for Faradaic component and greater than 0.994 for capacitive component. In the effect, DP voltammograms of Pb(II) and Cd(II) recorded on silver annular band electrode were constructed using only Faradaic component. Quantitative analysis was performed and calibration models were calculated by different waiting time and sampling time, what demonstrated the possibility of significant improvement of sensitivity in considered experiments.

Graphical abstract

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