Search

In this paper, PbO2 anode was prepared by pulse electrodeposition. The effect of temperature and current density on the thickness, micromorphology, crystal structure and grain size, and the deposition process was proposed and demonstrated by XPS. Furthermore, the effect of temperature and current density on the current efficiency, overpotential, and charge transfer resistance was systematically investigated by electrochemical properties, and the corresponding mechanism was analyzed. The results exhibit that the optimized temperature of the plating solution is about 50 °C. The electrode prepared at the current density of 400 A/m2 exhibits the highest current efficiency, while the electrode prepared at the current density of 300 A/m2 presents lower overpotential (0.7548 V) and smaller charge transfer resistance. This work provides a reference for the efficient electrodeposition of PbO2 composite electrodes. [ABSTRACT FROM AUTHOR]

The microstructure of the Pb-Ag alloy is vital to its mechanical, corrosion, and electrochemical properties. In this paper, heat preservation mold is used to control the temperature of cast lead alloy, realizing the regulation of the microstructure of Pb-Ag alloy. The effects of the surface microstructure and the Ag distribution on the mechanical, corrosion-resistant, and electrochemical properties of lead alloy are investigated. The results show that the heat preservation treatment effectively enhances the longitudinal tissue uniformity of the alloy and optimizes the distribution of Ag in the alloy. The alloy shows the best comprehensive performance as the heat preservation temperature reaches 50℃ due to the uniform size of the metallographic structure and the most uniformly distributed Ag. The low-temperature heat preservation treatment (12℃) refines the middle and bottom grains of the alloy and enhances the mechanical properties of the alloy. However, the increased uniform grain size and Ag distribution at the longitudinal level of the alloy led to a decrease in the electrochemical properties and corrosion resistance. [ABSTRACT FROM AUTHOR]

To obtain PbO2 anodes with high oxygen evolution activity and long lifetimes in zinc electrowinning, Ti/Sn-SbOX/β-PbO2 composite electrodes were prepared by pulse electrodeposition. The impact of pulse parameters including pulse duration and duty cycle on the surface morphology, phase composition, and electrochemical performance of Ti/Sn-SbOX/β-PbO2 electrodes was systematically investigated. The electrochemical measurements and accelerated life tests suggested that the composite electrode prepared with a pulse duration of 300 ms exhibited the lowest oxygen evolution potential and longest service life. The crystal size of the PbO2 active layer along the (110), (101), and (211) planes decreased after decreasing the duty cycle. As a result, the PbO2 layer obtained under a pulse duration of 300 ms and 10% duty cycle displayed a small, dense, and uniform crystal size distribution. The oxygen evolution potential was 0.365 V lower than that of the electrode obtained under direct current model, and the accelerated life was increased by 24.4 h. These results provide a promising deposition method for the preparation of composite anode materials in zinc electrowinning. [ABSTRACT FROM AUTHOR]