Co/Sm-modified Ti/PbO2 anode for atrazine degradation: Effective electrocatalytic performance and degradation mechanism

Shouxian Chen; Ping He; Xuejiao Wang; Feng Xiao; Pengcheng Zhou; Qihang He; Lingpu Jia; Faqin Dong; Hui Zhang; Bin Jia; Hongtao Liu; Bin Tang

doi:10.1016/j.chemosphere.2020.128799

Co/Sm-modified Ti/PbO₂ anode for atrazine degradation: Effective electrocatalytic performance and degradation mechanism

Chemosphere. 2021 Apr:268:128799. doi: 10.1016/j.chemosphere.2020.128799. Epub 2020 Nov 6.

Authors

Shouxian Chen¹, Ping He², Xuejiao Wang¹, Feng Xiao¹, Pengcheng Zhou¹, Qihang He¹, Lingpu Jia¹, Faqin Dong³, Hui Zhang⁴, Bin Jia⁵, Hongtao Liu⁶, Bin Tang⁷

Affiliations

¹ State Key Laboratory of Environment-friendly Energy Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang, 621010, PR China.
² State Key Laboratory of Environment-friendly Energy Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang, 621010, PR China; International Science and Technology Cooperation Laboratory of Micro-nanoparticle Application Research, Southwest University of Science and Technology, Mianyang, 621010, PR China. Electronic address: [email protected].
³ Key Laboratory of Solid Waste Treatment and Resource Recycle of Ministry of Education, Southwest University of Science and Technology, Mianyang, 621010, PR China.
⁴ International Science and Technology Cooperation Laboratory of Micro-nanoparticle Application Research, Southwest University of Science and Technology, Mianyang, 621010, PR China; Department of Chemical and Biochemical Engineering, Western University, London, Ontario, N6A 5B9, Canada.
⁵ International Science and Technology Cooperation Laboratory of Micro-nanoparticle Application Research, Southwest University of Science and Technology, Mianyang, 621010, PR China; Key Laboratory of Shock and Vibration of Engineering Materials and Structures of Sichuan Province, Southwest University of Science and Technology, Mianyang, 621010, PR China.
⁶ College of Chemistry and Chemical Engineering, Central South University, Changsha, 410083, PR China. Electronic address: [email protected].
⁷ School of Basic Medical Sciences, Southwest Medical University, Luzhou, 646000, Sichuan, PR China. Electronic address: [email protected].

PMID: 33187658
DOI: 10.1016/j.chemosphere.2020.128799

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, Na₂SO₄ 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.

Keywords: Atrazine pesticide wastewater; Condition optimization; Electrochemical oxidation; Hydroxyl racial; Mechanism analysis; Ti/PbO(2)–Co-Sm electrode.

MeSH terms

Atrazine*
Electrodes
Oxidation-Reduction
Oxides
Titanium
Water Pollutants, Chemical* / analysis

Substances

Oxides
Water Pollutants, Chemical
Titanium
Atrazine