Abstract: A novel high-performance PbO₂ electrode modified with Bi³⁺ (Bi-PbO₂) was prepared by electrodeposition. The microstructure and electrochemical properties of the modified electrode were investigated using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), fluorospectrophotometry (FP), Mott-Schottky analysis, electrochemical impedance spectroscopy (EIS), and linear-sweep voltammetry (LSV). The results of SEM, EDS, XPS, XRD, and UV-Vis DRS show that insertion of Bi³⁺ , which is in the form of Bi₂O₃, into the PbO₂ film can reduce its particle size, change its crystal cell parameters, and narrow its bandgap (E_g). FP analysis reveals that the electrocatalytic activity of the Bi-PbO₂ electrode in the degradation of organic materials is higher than that of the PbO₂ electrode because more hydroxyl radicals can be generated on its surface. Electrochemical performance tests show that the modified electrode has a more negative flat-band potential (E_fb), larger active surface area, lower charge-transfer resistance, and higher oxygen-evolution potential; these characteristics promote the electrocatalytic activity of the Bi-PbO₂ electrode in the decomposition of organic materials.

Key words: Bismuth, Lead dioxide, Bandgap, Flatband potential, Electro-catalytic activity