Electrochemical properties of powder-pressed Pb-Ag-PbO2 anodes
(1. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;
2. Zhuzhou Smelter Group Company Limited, Zhuzhou 412004, China;
3. Guizhou R&D Center of Titanium Materials Co., Ltd., Zunyi 563004, China)
2. Zhuzhou Smelter Group Company Limited, Zhuzhou 412004, China;
3. Guizhou R&D Center of Titanium Materials Co., Ltd., Zunyi 563004, China)
Abstract: Pb-Ag-PbO2 composite anodes with different mass fractions (1%, 2%, 3%, 4% and 5%) of β-PbO2 were prepared by powder-pressed (PP) method. The galvanostatic polarization curves, Tafel curves and anodic polarization curves were tested in sulfuric acid solution. The morphologies and phase compositions of the anodic layers formed after galvanostatic polarization were investigated by using scanning electron microscope (SEM) and X-ray diffractometer (XRD), respectively. The results showed that β-PbO2 can improve the electrocatalytic activity of anodic oxide. The anode containing 3% β-PbO2 had the lowest overpotential of oxygen evolution reaction (OER) and the best corrosion resistance. The morphologies of the anode surfaces were gradually transformed from regular crystals to amorphous ones as the content of β-PbO2 increased in anodes.
Key words: power-pressed Pb-Ag-PbO2 anode; oxygen evolution overpotential; electrochemical properties; zinc electrowinning