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The fast electrochemical deposition of both mercury and amalgam films, a crucial step in analytical anodic stripping voltammetry, is demonstrated to occur in the presence of power ultrasound emitted from an immersion horn probe which was placed opposite the working electrode in a conventional three electrode cell. Due to considerably enhanced mass transport the rate of deposition is strongly increased compared to 'silent' conditions. The total amount of mercury adhering to a glassy carbon electrode surface, however, is limited to a 'thin film' of microscopically small droplets of mercury as shown by atomic force microscopy and voltammetry. Due to surface forces induced by ultrasound, abrasion of some of the deposit occurs and after a certain period of time the parallel electro-deposition and abrasion processes reach a 'steady state'.

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Voltammetric measurements of the rates of fast homogeneous chemical reactions coupled to heterogeneous electron transfer at macroelectrodes are demonstrated for two systems, the reductive dehalogenations of ortho-bromonitrobenzene and of 3-bromobenzophenone, by the use of power ultrasound to confer fast mass-transport properties so giving the electrodes the kinetic timescale of microelectrodes.