Laser microtextured PWF/rGO@PVA photocatalytic membranes with high stability and reusability in wastewater remediation

In this study, a PWF/rGO@PVA photocatalytic membrane with high stability and reusability was successfully prepared by employing a blending-coating method. Through the innovative introduction of high thermal conductivity rGO, the membrane achieved enhanced photothermal conversion, which facilitates molecular diffusion and reduces reaction energy barriers. Simultaneously, rGO acts as an electron bridge to promote charge separation and suppress carrier recombination. With an optimal photocatalyst content of 5 wt%, the PWF/rGO@PVA membrane exhibited excellent degradation rates of 0.0112 min⁻¹ and 0.0101 min⁻¹ under UV and visible light respectively, and maintained over 70% removal efficiency after five cycles. Selective laser texturing was then applied to the membrane surface, achieving degradation rates of 96.7% and 93.6% under UV and visible light respectively, and maintained over 90% removal efficiency after five cycles. On one hand, the created periodic microstructures increased specific surface area which provided additional adsorption sites and reaction interfaces and significantly enhanced the anti-reflective properties of the membrane surface. On the other hand, the laser texturing process disrupts the hydrogen bonding network of PVA, thereby suppressing warpage deformation during photocatalytic cycling and improving structural stability. Finally, the dynamic water experiments verified that at a flow rate of 1.0 mL/min, the photocatalytic membrane retained over 80% degradation efficiency and maintained high photocatalytic stability in dynamic water environments with varying pH and the presence of inorganic anions.