Preparation and characteristics of a nano-PbO2 anode for organic wastewater treatment

A nano-PbO2 anode (PbO2/NT) was prepared by a pulse electrodeposition (PED) method. Self-organized TiO2 nanotube (NT) arrays were produced by electrochemical anodization and used as a substrate to load PbO2 by PED method. The morphological and structural properties were studied by the field-emission scanning electron microscopy and X-ray diffraction revealing successful deposition of lead dioxide nanoparticles on the NT walls. The electrochemical activity of PbO2 loaded on TiO2 nanotube arrays electrode (PbO2/NT) was found to be influenced by the length of electrochemical plating time. Chronoamperometric experiments showed that PbO2/NT anodes possessed stronger oxidation ability than that of traditional PbO2 anodes (PbO2/Ti). PbO2/NT, due to its unique microstructure, could oxidize chlorine effectively under basic conditions. The effect of current density on total organic carbon (TOC) removal by PbO2/NT varied with different organic reactants used. The TOC removal rate of isopropanol was controlled by mass transfer, while the removal rate of 4-chlorophenol (4-CP) was mainly influenced by passivation. The synergistic effects of pH, flow rate, and supporting electrolyte on the TOC removal percentage using PbO2/NT or PbO2/Ti were investigated as well. (C) 2010 Elsevier B.V. All rights reserved.