Engineering MoS₂/Fe₂O₃/graphene oxide–coated PVDF membranes for enhanced self-cleaning and antifouling performance under simulated solar light in dye wastewater treatment
L. Vishoda Samarasinghe, Shobha Muthukumaran, Kanagaratnam Baskaran
Abstract
Membrane separation is extensively used in water treatment; however, the accumulation of contaminants on the membrane surface continues to pose a major challenge in real-world applications. Photocatalytic technology offers an efficient and environmentally friendly approach for pollutant degradation. Here, we report a simple method to prepare MoS 2 /Fe 2 O 3 /GO (MFG) coated PVDF photocatalytic membranes and evaluate their multi-functional abilities for water treatment. Incorporation of MFG increased the surface hydrophilicity and produced a markedly rougher surface. The coated membranes achieved 94.6 % total methylene blue (MB) removal through the combined sequential action of filtration, adsorption and photocatalysis under solar-simulated irradiation, maintaining 90.3 % removal efficiency after three reuse cycles, while the permeate flux decreased only modestly from 74.4 to 68.8 kg·m −2 ·h −1 . Photocatalytic MB degradation by the MFG-coated membranes followed apparent pseudo-first-order kinetics under both UV and solar-simulated light irradiation. All the membranes showed improved performance under simulated solar light compared to UV irradiation due to the efficient charge separation, broadened visible light absorption and redox capability of the heterostructure photocatalyst. Fouling tests showed flux recovery ratios (FRR) >80 % after physical cleaning for all composite membranes, and FRR further improved after light treatment (up to ~97 %). These results demonstrate a practical route for engineering highly efficient, multi-functional, and self-cleaning membranes for sustainable water treatment.