Nonradical-dominated nanoconfined iron single-atom catalytic membrane to enhance peroxymonosulfate activation for efficient water decontamination

Peijie Li; Daliang Xu; Xiaoxiang Cheng; Peng Liu; Xinsheng Luo; Jiaxuan Yang; Heng Liang

doi:10.1016/j.watres.2025.124106

Nonradical-dominated nanoconfined iron single-atom catalytic membrane to enhance peroxymonosulfate activation for efficient water decontamination

Water Res. 2025 Jun 24:285:124106. doi: 10.1016/j.watres.2025.124106. Online ahead of print.

Authors

Peijie Li¹, Daliang Xu¹, Xiaoxiang Cheng², Peng Liu¹, Xinsheng Luo², Jiaxuan Yang³, Heng Liang¹

Affiliations

¹ State Key Laboratory of Urban-rural Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
² School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, PR China.
³ State Key Laboratory of Urban-rural Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China. Electronic address: hityangjiaxuan@163.com.

PMID: 40580834
DOI: 10.1016/j.watres.2025.124106

Abstract

Catalytic membrane reactors (CMRs) exhibit significant advantages in the removal of contaminants of emerging concern. However, the impairment inflicted on polymer membranes by radicals and the radical scavenging induced by natural organic matter constrain the advancement of CMRs. Herein, we designed an iron single-atom catalyst (FePc-O-CNT) dominated by nonradical oxidation mechanisms and combined it with peroxymonosulfate (PMS) to develop a CMR system (FePc-O-CNT membrane/PMS). The system exhibited superior degradation activity to multiple pollutants via nonradical pathways. The nanoconfined membrane space facilitated PMS activation and enhanced singlet oxygen generation and mass transfer, resulting in a 9513-fold enhancement for bisphenol A (BPA) degradation kinetics over the heterogeneous suspensions. Moreover, the system performed robustly in complex water matrices even under severe membrane fouling (60 % or 80 % flux declines). Unlike radical-based processes, the FePc-O-CNT membrane/PMS system maintained excellent permeability, with only a 7.4 % flux loss after 84 h filtration. For engineering validation, the FePc-O-CNT membrane was also fabricated through non-solvent induced phase separation, which achieved ∼100 % BPA removal and minimal iron leaching over 48 h operation. This research introduces a nonradical-dominated CMR system that addresses the limitations of radical-dominated catalytic degradation, providing foundational insights for advanced membrane-based water purification processes.

Keywords: Catalytic membrane reactors; Contaminants of emerging concern; Nanoconfinement effect; Nonradical oxidation mechanisms; Peroxymonosulfate activation.