Stable boron and cobalt co-doped TiO2 nanotubes anode for efficient degradation of organic pollutants

Jingju Cai; Minghua Zhou; Xin Xu; Xuedong Du

doi:10.1016/j.jhazmat.2020.122723

Stable boron and cobalt co-doped TiO₂ nanotubes anode for efficient degradation of organic pollutants

J Hazard Mater. 2020 Sep 5:396:122723. doi: 10.1016/j.jhazmat.2020.122723. Epub 2020 Apr 17.

Authors

Jingju Cai¹, Minghua Zhou², Xin Xu¹, Xuedong Du¹

Affiliations

¹ Key Laboratory of Pollution Process and Environmental Criteria, Ministry of Education, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China; Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution, Nankai University, Tianjin 300350, China; Tianjin Key Laboratory of Urban Ecology Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China; Tianjin Advanced Water Treatment Technology International Joint Research Center, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China.
² Key Laboratory of Pollution Process and Environmental Criteria, Ministry of Education, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China; Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution, Nankai University, Tianjin 300350, China; Tianjin Key Laboratory of Urban Ecology Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China; Tianjin Advanced Water Treatment Technology International Joint Research Center, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China. Electronic address: zhoumh@nankai.edu.cn.

PMID: 32344364
DOI: 10.1016/j.jhazmat.2020.122723

Abstract

Anode materials are crucial to anodic oxidation for wastewater treatment. In this regard, stable boron and cobalt co-doped TiO₂ nanotube (B, Co-TNT) was prepared for the first time, and its lifetime was found increased significantly while electrocatalytic activity decreased with the increase of Co(NO₃)₂ in preparation from 1 to 10 mM. Characterized by scanning electron microscope (SEM), X-Ray Diffraction (XRD) and X-ray Photo-electronic Spectroscopy (XPS), B and Co content were optimized and successfully doped on TNT, which was more smooth without ripple with Co content of 0.038 mg/cm² in a valence of +2, and B atomic content of 2.17 at.% in form of Ti-B-O. This optimized anode enhanced electrode lifetime 122.8 times while the electrochemical activity decreased slightly when compared to the undoped TNT. The effects of current density, initial pH and initial 2,4-dichlorophenoxyacetic acid (2,4-D) concentration were investigated, and the mainly responsible radical for degradation was confirmed to be the surface OH on B, Co-TNT anode. This anode had better performance on the TOC removal, mineralization current density (MCE) and energy consumption (Ec) when compared with BDD, PbO₂, DSA and Pt anodes, and it also presented a very stable degradation for 10 cycles oxidation of 20 mg/L 2,4-D with allowable Co leaching. Therefore, B, Co-TNT anode is a promising, stable, safety and cost-effective anode for application in electrochemical advanced oxidation processes (EAOPs).

Keywords: 2,4-dichlorophenoxyacetic acid; Boron and cobalt co-doping; Hydroxyl radical; TiO(2) nanotubes.

Publication types

Research Support, Non-U.S. Gov't