Lead dioxide deposition and electrocatalysis at highly boron-doped diamondelectrodes in the presence of ultrasound

Boron-doped diamond (BDD) is a versatile and novel electrode material which , due to its mechanical and chemical robustness, wide potential window, low background interference, and ease of chemical modification, is becoming an interesting alternative to conventional electrodes for a wide range of ele ctrochemical applications. It is shown in this study that BDD is a good sub strate for the ultrasound-enhanced electrodeposition of lead dioxide, produ cing strongly adhered electrically conducting deposits. Power ultrasound is used to enhance both the efficiency of the PbO2 deposition procedure and t he rate of the electrocatalytic ethylene glycol oxidation process at the Pb O2-modified BDD electrode. The presence of high levels of aqueous organic m aterial is shown to interfere with the lead dioxide deposition process. Und er optimized insonation conditions the PbO2 deposit, quantified by using ca thodic shipping voltammetry, is shown to be mechanically stable. When used in conjunction with power ultrasound to perform the electrocatalytic oxidat ion of ethylene glycol two distinct types of oxidation processes at PbO2, c hemically rate limited and electrochemically rate limited, are observed. (C ) 2001 The Electrochemical Society. All rights reserved.