Electrode cleaning and activation

A notable benefit of the asymmetric collapse of cavitation bubbles at solid/liquid interfaces is the resulting cleaning effect which may be beneficially exploited in the context of the voltammetry of adsorbing or passivating systems. 

Various workers have reported electrode damage and/or roughening in the presence of ultrasound. Thus insonation of glassy carbon electrodes leads to their activation (Zhang and Coury, 1993) and AFM images of ultrasound-induced surface modifications have been described (Marken et al., 1996b). For the case of platinum electrodes, substantial roughening was found, both 

The benefits of electrode erosion in preserving electrode activity have been seen in the cases of electrogenerated polymers (Madigan et al., 1994), where the ultrasound punches holes through the film, the deposition of reduced methylviologen, which can otherwise passivate an electrode surface under silent conditions (Benahcene et al., 1995), and the oxidation of Cr(CO)6, where insonation counters electrode poisoning (Compton et al., 1994). 

A major future application of sonovoltammetry may well lie in the field of electroanalysis where the ability to maintain electrode activity in dirty or otherwise passivating media may extend the range of applicability of such procedures. Reports of the benefits of insonation in anodic and adsorptive stripping voltammetry are just beginning to appear (Marken et al., 1997a Matysik et al., 1997 Agra-Gutierrez and Compton, 1998). 

---

Sonovoltammetry mass transport effects - further aspects 80 Electrode cleaning and activation 81 Electrode kinetics 82... 

---