Self-cleaning nanocomposite membranes based on sulfonated tetrafluoroethylene and g-C₃N₄ for water purification

Water contamination from industrial effluents is a significant environmental challenge due to the presence of organic dyes. This study presents the development of self-cleaning nanocomposite membranes based on sulfonated tetrafluoroethylene and 2D graphitic carbon nitride (g-C₃N₄) nanosheets for efficient water purification. The membranes were synthesized using solution casting with 1 and 5 wt. % g-C₃N₄ as a photocatalytic filler. A comprehensive physicochemical characterization was conducted using XRD, FTIR, SEM, DRS, and adsorption tests. The photocatalytic performance was assessed through the degradation of methylene blue under visible light. Results show that membranes with 5 wt. % g-C₃N₄ exhibit enhanced adsorption efficiency (k = 0.0800 min^-1) and notable photocatalytic activity (k = 0.0083 min^-1), leading to effective dye removal and self-cleaning functionality. These findings highlight the potential of hybrid polymer-nanomaterial membranes for sustainable wastewater treatment. The proposed membranes offer a promising solution for removing hazardous organic pollutants while maintaining long-term operational stability.

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