Lauryl benzene sulfonic acid sodium-carbon nanotube-modified PbO2 electrode for the degradation of 4-chlorophenol

Abstract

The lauryl benzene sulfonic acid sodium (LAS)-carbon nanotube (CNT)-modified PbO2 electrode was fabricated by thermal deposition and electrodeposition methods. Its morphology and composition were compared with those of PbO2, CNT-PbO2, and LAS-PbO2 electrodes. It was found that CNT could be doped into the PbO2 film in the presence of LAS. The [Fe(CN)6]4−/3− redox couple in 0.1M KCl was used for initial evaluation of the electro-catalytic activity of prepared electrodes. The results showed that LAS-CNT-PbO2 electrode exhibited the largest peak current and the smallest ΔEp in [Fe(CN)6]4−/3− redox process. The stability tests showed that the service life of LAS-CNT-PbO2 electrode was 1.8 times longer than that of PbO2 electrode. The electro-catalytic activity of the prepared electrodes was also examined for the electrochemical oxidation of 4-chlorophenol (4-CP) and the LAS-CNT-PbO2 electrode exhibited the highest activity for 4-CP degradation among the four PbO2-based electrodes. Besides, HPLC was employed to identify the products resulting from the electrochemical oxidation of 4-CP and the degradation mechanism of 4-CP was also discussed.