Preparation Of Lead Dioxide Electrode And Modification Study

Because lead dioxide electrode has good electrical conductivity,corrosion resistance,practice under high current conditions,lower prices and other advantages,lead dioxide ekectrode is widely industrial application.However,there are some flaws in the application of lead dioxide electrode:the adhesion between the coating and the substrate coating is easy to fall off,and the catalytic activity is not high.It is hard to meet the requirement of the development of industrialization.Therefore,lead dioxide electrode is appealing for further exploration and research to improve the stability and catalytic activity.In this thesis,the sol-gel and dip-coating method was used to prepare the mediated layer of tin antimony iridium mixed oxides and the mediated layer of ruthenium iridium titanium mixed oxides,and the electrodeposition method with constant temperature and constant current was employed to prepare Ti/Sn-Sb-Ir/PbO₂ and Ti/Ru-Ir-Ti/PbO₂ electrodes.Through some characterizations including XRD,SEM,LSV,accelerated life tests and the degradation of phenol,the optimal coating numbers for Sn-Sb-Ir intermediate layer and Ru-Ir-Ti intermediate layer were determined.Ti/Sn-Sb-Ir/PbO₂ electrode with the best intermediate layer number of 4 has the phenol removal efficiency of 87.6%,and the accelerated life of61.24 h in 1mol/L H₂SO₄ solution under the current density of 1A/cm²;Ti/Ru-Ir-Ti/PbO₂electrode with the optimal intermediate layer number of 4 has the phenol removal efficiency of 85.6%,and the accelerated life of 65.61h.On the basis of the optimal number of intermediate layers,electrochemical doping modification was applied to improve the performance and stability of the electrodes.After doping nano-TiN,Ti/Sn-Sb-Ir/PbO₂+TiN electrode has the phenol removal rate of 89.3%,and the cell voltage of 4.20V.Ti/Ru-Ir-Ti/PbO₂+TIN electrode has the phenol removal rate of87.2%,the accelerated life of 352.50h.After doping CNT,the removal rates of phenol on Ti/Sn-Sb-Ir/PbO₂+CNT and Ti/Ru-Ir-Ti/PbO₂+CNT electrodes were 93.3%and 89.8%,respectively.3D PbO₂ based on carbon nanotubes coated sponge electrode has a fine and uniform layer.New type of lead dioxide electrode has peak a current density of 4.86mA/cm² for phenol oxidation.The 3D lead dioxide electrode has a phenol removal rate of 93.1%.