Co/Sm-modified Ti/PbO2 anode for atrazine degradation: Effective electrocatalytic performance and degradation mechanism. (April 2021)

• Record Type: Journal Article
• Authors: Chen, Shouxian; He, Ping; Wang, Xuejiao; Xiao, Feng; Zhou, Pengcheng; He, Qihang; Jia, Lingpu; Dong, Faqin; Zhang, Hui; Jia, Bin; Liu, Hongtao; Tang, Bin
• Is Part Of: Chemosphere. Volume 268(2021)
• Publication Date: 2021-04
• Subjects: Atrazine pesticide wastewater -- Electrochemical oxidation -- Ti/PbO2–Co-Sm electrode -- Condition optimization -- Hydroxyl racial -- Mechanism analysis; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2020.128799
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: In this work, Ti/PbO2 –Co-Sm electrode has been successfully prepared using electrodeposition and further applied for the electrocatalysis of atrazine (ATZ) herbicide wastewater. As expected, Ti/PbO2 –Co-Sm electrode displays highest oxygen evolution potential, lowest charge transfer resistance, longest service lifetime and most effective electrocatalytic activity compared with Ti/PbO2, Ti/PbO2 -Sm and Ti/PbO2 –Co electrodes. Orthogonal and single factor experiments are designed to optimize the condition of ATZ degradation. The maximum degradation efficiency of 92.6% and COD removal efficiency of 84.5% are achieved in electrolysis time 3 h under the optimum condition (current density 20 mA cm −2, Na2 SO4 concentration 8.0 g L −1, pH 5 and temperature 35 °C). In addition, Ti/PbO2 –Co-Sm electrode exhibits admirable recyclability in degradation progress. The degradation of ATZ is accomplished by indirect electrochemical oxidation and ∙OH is tested as the main active substance in ATZ oxidation. The possible degradation mechanism of ATZ has been proposed according to the degradation intermediates detected by LC-MS. This research suggests that Ti/PbO2 –Co-Sm is a promising electrode for ATZ degradation. Graphical abstract: Image 1 Highlights: Co/Sm co-modified Ti/PbO2 anode is fabricated by one-step electrodeposition. Ti/PbO2 –Co-Sm anode presents compact pyramidal structure with large surface area. Ti/PbO2 –Co-Sm anode displays high oxygen evolution potential and superb stability. Ti/PbO2 –Co-Sm anode shows excellent catalytic activity for atrazine degradation. Degradation condition is optimized and possible degradation mechanism is proposed.