Tubular F-doped porous carbon/CNT membrane with electron redistribution for enhanced self-cleaning and sustainable wastewater treatment

Abstract

A series of self-standing tubular membranes were fabricated by incorporating F-doped polyaniline-derived porous carbon (F-PPC) with carbon nanotubes (CNTs) at systematically varied mass ratios (CNT:F-PPC = 1:2, 1:1, 2:1) for electro-Fenton filtration applications. Comprehensive structural and physicochemical characterization indicated that compositional control can effectively regulate the membrane properties. Specifically, increasing the CNT content can modulate the electrocatalytic performance, microstructure, and electron density distribution of the hybrid membranes. Among the configurations, the C1P1 membrane (CNT:F-PPC = 1:1) achieved an optimal balance, featuring a moderate pore size, appropriate hydrophobicity (94.36°), and satisfactory conductivity (33.1 Ω), indicating synergistic effects between defect-mediated catalytic activity and conductive pathways for reactive oxygen species generation. Under electrochemical assistance, the C1P1 membrane exhibited superior antifouling performance and contaminant removal efficiency, achieving complete bovine serum albumin rejection, along with 33.7% degradation of glucose and 38.6% degradation of humic acid. The enhanced performance can be attributed to the balanced degree of graphitization and defect density resulting from fluorine-induced electron redistribution. This redistribution synergistically promotes both the 2e^– oxygen reduction reaction and the Fenton pathway for the efficient production of ·OH. This work establishes fundamental structure–property relationships in multifunctional carbon membranes and provides a sustainable strategy for integrated wastewater treatment through simultaneous filtration and electro-Fenton processes.

Graphical abstract

Keywords

Fluorine / Polyaniline-derived porous carbon / Electro-Fenton / ·OH / Membrane fouling

Highlight

	● Integrated electro-Fenton filtration was achieved using CNT/F-PPC membranes.
	● The properties were precisely modulated by varying the CNT-to-F-PPC ratio.
	● The C1P1 membrane showed optimal performance with the highest ·OH generation.
	● The membranes enabled both separation and electrocatalytic degradation ability.

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