Electrospun PVDF Composite Membranes with V ₂ CT x MXene and ZnO Nanostructures with Antimicrobial Properties and Photothermal Effect for Purification of Water

The development of multifunctional polymer membranes for oil/water separation and contaminant remediation has attracted significant attention; however, many reported systems suffer from limited passive light activation, rapid charge recombination, and reduced catalytic efficiency under low-light or shaded conditions. In this work, we report a multifunctional electrospun polyvinylidene fluoride (PVDF)-based membrane, termed as ZnReef, incorporating vanadium-based MXene (V 2 CT x ) and zinc oxide (ZnO) nanostructures. The developed membrane exhibits dual functionality by enabling efficient oil/water separation alongside sonophotocatalytic degradation of emerging contaminants. The intimate interfacial contact between V 2 CT x and ZnO promotes the formation of a Schottky heterojunction, facilitating charge separation and inhibition of electron–hole recombination under UV irradiation and ultrasonic stimulation. As a result, the membrane generated enhanced reactive oxygen species, enabling efficient catalytic degradation. The ZnReef membrane achieved an oil/water separation efficiency of 98.90% with a permeation flux of 2080 L m –2 h –1 and maintained stable performance over 100 separation cycles. Sonophotocatalytic degradation efficiencies of 91.52% for methylene blue and 88.33% for ciprofloxacin were obtained within 90 min, with corresponding apparent rate constants of 2.77 × 10 –2 min –1 and 2.36 × 10 –2 min –1 respectively. Compared with pristine PVDF and previously reported MXene or ZnO based membranes, ZnReef demonstrated enhanced catalytic activity, antifouling resistance, and long-term operational stability. The membrane also exhibited strong antimicrobial activity against Arthrospira platensis, achieving a high inhibition efficiency in 24 h. In addition, ZnReef displayed a photothermal response of 27.2 to 61.2 °C, tensile strength, and excellent durability under acidic, alkaline, saline, and reactive environments for over 48 h. These results demonstrate that ZnReef integrates efficient oil/water separation, broad-spectrum contaminant degradation, mechanical robustness, and environmental stability within a single platform, illustrating its potential for advanced water purification applications.