Coupling anodic and cathodic reactions using an electrocatalytic dual-membrane system actuates ultra-efficient degradation with regulable mechanisms

Yifan Gao; Shuai Liang; Quanbiao Zhang; Kunpeng Wang; Peng Liang; Xia Huang

doi:10.1016/j.watres.2023.119741

Coupling anodic and cathodic reactions using an electrocatalytic dual-membrane system actuates ultra-efficient degradation with regulable mechanisms

Water Res. 2023 Apr 15:233:119741. doi: 10.1016/j.watres.2023.119741. Epub 2023 Feb 14.

Authors

Yifan Gao¹, Shuai Liang², Quanbiao Zhang¹, Kunpeng Wang¹, Peng Liang¹, Xia Huang³

Affiliations

¹ State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China.
² Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China. Electronic address: shuai_liang@bjfu.edu.cn.
³ State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China. Electronic address: xhuang@tsinghua.edu.cn.

PMID: 36804338
DOI: 10.1016/j.watres.2023.119741

Abstract

The versatile reaction possibilities arising from the interaction between the anodic and cathodic reactions naturally contained in electrocatalytic membrane filtration (EMF) systems are of great valuable in meeting the current complex water treatment requirements. But currently, most studies only focus on half-cell reactions with a single electrocatalytic membrane, which limits the research progress of the EMF technology. Here we report a coupling strategy that utilizes the interaction between the anodic and cathodic reactions to actuate ultra-efficient degradation performance with regulable reaction mechanisms. An electrocatalytic dual-membrane filtration (EDMF) system was established. Six typical configurations of the EDMF system were set up and systematically investigated by adjusting the electrode distance and filtration sequence. Based on the obtained results of degradation performance and mechanisms, a regulation strategy which enabled flexible tuning of direct nonradical oxidation (e.g., h⁺) and indirect oxidation (e.g., ¹O₂, ·OH, HO₂·, O₂·^-, etc.) was proposed. In particular, cathodic reactions were found to adversely affect the anodic reactions at the relatively short electrode distance of 0.9 mm. Anodic reactions could inhibit the generation of ¹O₂ at short distance of 0.9 mm but promote its generation at long distances of 9 and 17 mm. The A-C_0.9 configuration achieved the highest degradation performance, while the C-A_9 configuration was revealed to be much more conducive to ¹O₂ production. Overall, our findings demonstrate the versatility and tunability of the reaction mechanism and performance of the EDMF system due to the flexible coupling of the anodic and cathodic reactions, which potentially lays a foundation for future development of ultra-efficient mechanism-adjustable electrocatalysis technologies.

Keywords: Coupling reactions; Dual-membrane system; Electrocatalytic degradation; Electrocatalytic membrane; Reaction interaction; Tuning mechanism.

MeSH terms

Electrodes
Oxidation-Reduction
Water Purification* / methods