Ultrasound Research Today is a free monthly online journal that collates and summarizes the latest research about Ultrasound, including details on screening, diagnosis, pregnancy, detection.

Electrochemical study of silver thiosulphate reduction in the absence and presence of ultrasound.

Pollet B, Lorimer JP, Hihn JY, Touyeras F, Mason TJ, Walton DJ

School of Science and the Environment, University of Coventry, Coventry CV1 5FB, UK. polleb@matthey.com

The electrochemical reduction of silver thiosulphate was studied potentiostatically on platinum electrodes in the absence and presence of ultrasound (20 kHz). This system is irreversible and the reaction is both diffusion and kinetically controlled. The slowest step is the kinetic reaction especially the chemisorption of ions at the electrode surface. Ultrasound greatly improves the mass transport, which can be explained by changing from diffusion to mainly convection. This paper reports the effect of ultrasound upon electrode kinetic and mass-transport parameters at various RDE rotation speeds and ultrasonic intensities. It was found that the heterogeneous rate constant (kf) is improved in the presence of ultrasound due to the increase in the formal or standard heterogeneous rate constant (k0) (approximately by 10-fold under sonication).

Published 11 October 2004 in Ultrason Sonochem, 12(1): 7-11.
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