Chaotic, mixed-mode and periodic oscillations during the electro-oxidation of copper in trichloroacetic acid

Abstract

The current oscillations of a copper electrode in trichloroacetic acid solutions were studied in this paper. The Cu/CCl3COOH system is a new electrochemical oscillator, showing rich dynamic behaviour on two controllable parameters: the trichloroacetic acid concentration (CCCl3COOH) and the imposed potential (E). Phase trajectories were reconstructed from time series using time delaymethods in order that the complex oscillations could be analyzed. Five kinds of oscillations, periodic and quasiperiodic mixed-mode, aperiodic, small amplitude and chaotic current oscillations, were observed. The EDS (energy dispersive spectroscopy) technique was used to analyze the elemental composition of the film formed on the surface of the copper electrode after the current oscillations.