A Novel Multifunctional Photocatalytic Separation Membrane Based on Single-Component Seaweed-Like g-C3N4

Multifunctional separation membrane is usually realized by multi-component collaborative construction, which makes the membrane preparation method complicated and uncontrollable. Herein, a novel multifunctional photocatalytic separation membrane is prepared by vacuum self-assembly of single seaweed-like g-C 3 N 4 photocatalyst. The seaweed-like g-C 3 N 4 gives membrane certain roughness, large specific surface area, excellent hydrophilicity and abundant transport channels. Through a systematic study, the membrane exhibits excellent separation of five oil-in-water emulsions with a maximum flux of 3114.0 ± 113.0 L m −2 h −1 bar −1 for 1, 2-dichloroethane-in-water (Dc/W) emulsion and a maximum efficiency of 97.4 ± 0.1% for chloroform-in-water (C/W) emulsion. In addition, the seaweed-like g-C 3 N 4 with large specific surface area and narrow bandgap render excellent visible light absorption characteristics and accelerate e − -h + pairs transport rate, giving the membrane excellent photocatalytic degradation and antibacterial properties. The membrane shows good degradation for eight different pollutants, among which the degradation effect for rhodamine B (RhB), methylene blue (MB), and crystal violet (CV) were ≈100%. The antibacterial efficiency against E. coli and S. aureus is also close to 100%. After 35 consecutive separations of C/W emulsion and 10 consecutive degradations of RhB, the membrane still maintains excellent separation performance. This long-lasting multifunctional separation membrane exhibits broad application prospects in complex wastewater purification.