Stability of mercury film electrodes under the influence of high frequency (500 kHz) ultrasound

Abstract

The analytical utility of coupling high frequency ultrasound (500 kHz) systems with electrochemical stripping techniques has been investigated. The stability of mercury film electrodes (on either glassy carbon or iridium substrates) under various ultrasound regimes was assessed with cavitational erosion found to occur irrespective of the substrate or position within the cell assembly. Removal of dissolved gas was found to increase the lifetime of the mercury film but only through sacrificing enhancements in mass transport. A second series of experiments investigated the influence of ultrasound frequency (20 and 500 kHz) on the stripping voltammetric determination of lead and cadmium at bare glassy carbon electrodes. The results were compared with silent conditions with the high frequency system shown to significantly enhance the accumulation of the target analyte.