Electrochemical Reduction of Perchlorate Ion on Porous Carbon Electrodes Deposited with Iron Nanoparticles

A method for degradation of the perchlorate anion (ClO4-) has been studied using electrochemically generated zero- valent iron (ZVI) deposited on a porous carbon electrode. The first strategy of this study is to produce the ZVI via the electrochemical reduction of iron (II) on a porous carbon electrode coated with a conducting polymer, instead of employing expensive NaBH4. The present method produced well distributed ZVI on conducting polymer (polypyrrole thin film) and increased surface area. ZVI surface can be regenerated easily for successive reduction. The second strategy is to apply a mild reducing condition (- 0.3 V) to enhance the efficiency of the degradation of perchlorate with ZVI without the evolution of hydrogen. The electrochemically generated ZVI nanoparticles may offer an alternative means for the complete destruction perchlorate without evolution of hydrogen in water with high efficiency and at low cost.