Construction of GO/Pr/PbO₂ ternary electrode for highly efficient degradation of organic pollutants

A series of GO/Pr/PbO₂ electrodes were prepared by electrodeposition method, and used for the electrocatalytic degradation of methylene blue (MB) in an electrolytic cell. The characteristic properties of the as-prepared electrodes were systematically characterized via different techniques such as XRD, SEM, and XPS. Interestingly, the ternary electrode was found to possess higher catalytic performance compared with PbO₂ and Pr/PbO₂ electrodes, suggested that synergistic catalytic activity existed between ternary electrode. Moreover, 94.64% of MB degradation was detected over the ternary electrode under the optimized conditions (50 mg/L, pH = 3, 180 min). Besides, when rhodamine B, methyl orange, acid red and tetracycline were respectively used as the model pollutants, with no less than 60% degradation being found. Additionally, hydroxyl radical (•OH) as reactive oxygen species was confirmed according to the free radical capture experiment, whereas, a proper degradation pathway was proposed. According to the DFT calculations, the electrons of the organic pollutants can be transferred to the anode via C-O-Pr bond and Pr-O-Pb bond between the dual interfaces.