Preparation of a Praseodymium Modified Ti/SnO2-Sb/PbO2 Electrode and its Application in the Anodic Degradation of the Azo Dye Acid Black 194

A series of praseodymium modified Ti/SnO 2 -Sb/PbO 2 (Ti/SnO 2 -Sb/PbO 2 -Pr) electrodes were synthesized by doping PbO 2 with praseodymium and the effect of Pr doping on the electrode catalytic activity toward the anodic oxidation of the model dye C.I. Acid Black 194 (AB-194) was examined in aqueous solution. The electrocatalytic activity of a Ti/SnO 2 -Sb/PbO 2 electrode can be greatly improved by adding an appropriate amount of Pr into the PbO 2 layer. Accelerated life tests indicate that Pr doping also dramatically improves the stability of the Ti/SnO 2 -Sb/PbO 2 anode. The introduction of Pr enhanced the formation of oxygen vacancies and surface hydroxyl groups, resulting in better activity and stability of the Ti/SnO 2 -Sb/PbO 2 -Pr electrode. A possible degradation pathway of AB-194 during the anodic oxidation process is proposed based on hydroxyl radical attack of the organic reactant.