Preparation and characterization of PbO2 electrodes modified with polyvinyl alcohol (PVA)

Abstract

Novel PbO₂ electrodes were successfully synthesized with polyvinyl alcohol (PVA) modification through electro-deposition technology. The morphology and crystalline structure of the electrodes were characterized by SEM and XRD, respectively. In addition, X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and accelerated life stability testing were also carried out to analyze the chemical state, electrochemical performances and stability of the electrodes. The results showed that PVA could refine the grain size and increase the oxygen evolution potential (OEP). After PVA modification, the predominant phase of the PbO₂ electrodes was unchanged and all were pure β-PbO₂. Besides, for modified electrodes, the electrode film impedance reduced and the proportion of adsorbed hydroxyl oxygen (O_ad) on the electrode increased, implying the fast charge transfer and excellent degradation efficiency for organics. In the process of dye oxidation, the PbO₂-2.0 vt% electrode showed the highest electrocatalytic activity for ARG degradation due to its highest OEP and massive O_ad. Moreover, the accelerated service life tests revealed that the PbO₂-2.0 vt% electrode exhibited the highest stability and the accelerated service life was 329.5 h, which was more than 3 times longer than that of the PbO₂-0 vt% electrode (96 h).