A novel bifunctional cathode for the generation and activation of H2O2 in electro-Fenton: Characteristics and mechanism. (20th October 2022)

• Record Type: Journal Article
• Authors: Xie, Fangshu; Gao, Ying; Zhang, Jingbin; Bai, Huiling; Zhang, Jianfeng; Li, Zhihua; Zhu, Weihuang
• Is Part Of: Electrochimica acta. Volume 430(2022)
• Publication Date: 2022-10-20
• Subjects: Metal-organic framework (MOF) -- Reduced graphene (rGO) -- Modification -- Bifunctional cathode -- H2O2 generation -- H2O2 activation -- Electro-Fenton; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2022.141099
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: External addition of Fe 2+ is commonly required for the sake of activating H2 O2 in electro-Fenton, which limits the reaction continuity and causes the potential secondary pollution. Herein, a novel bifunctional cathode (rGO/MIL-88A/CF) was fabricated for achieving the in-situ H2 O2 generation and activation simultaneously. The rotating disc electrode (RDE) test showed that the average electron transfer number was about 2.01, indicating that selective two-electron reduction of oxygen molecule (2e – ORR) occurred on the as-prepared cathode. The quenching experiments and EPR tests proved that the oxygen-containing reactive species such as OH and O2 – could be efficiently generated on rGO/MIL-88A/CF cathode, which contributed to the pollutant degradation. The obtained rGO/MIL-88A/CF cathode not only obtained the improvement of its charge transfer rate owing to the modification by the reduced graphene (rGO), but also acted as a stable activator for the electro-generated H2 O2 without additional reagents. Moreover, rGO/MIL-88A/CF cathode effectively facilitated the circulation of Fe 2+ /Fe 3+ through cathodic reduction, which consequently enhanced the performance of the electro-Fenton. Our current investigation presented a feasible example of a novel bifunctional cathode applied in electro-Fenton towards efficient pollutant removal without exogenous H2 O2 activator. Graphical abstract: Image, graphical abstract