Ultrasound-Assisted Rapid Adsorptive PVDF Microfiltration Membranes

Abstract Poly(vinylidene fluoride) (PVDF) membranes, renowned for their exceptional chemical stability and mechanical resilience, are widely utilized in various industrial applications. Nevertheless, conventional PVDF membranes rely solely on size exclusion and therefore can hardly remove dissolved contaminants smaller than the membrane pores. Here, we report a sucrose-modified PVDF membrane that enables the simultaneous removal of particulate and dissolved pollutants by integrating rapid adsorption with conventional microfiltration under ultrasonic irradiation. Under ultrasonic irradiation, the membrane achieved 95.7% removal of rhodamine B within 2 min. This rapid and effective removal was consistently observed for diverse pollutants, including dyes, antibiotics, and perfluorooctanoic acid (PFOA). The performance was further validated in natural water, where the prepared PVDF membrane simultaneously removed particulates and reduced chemical oxygen demand (CODCr), exceeding that of commercial PVDF filters. We also show that integrating piezoelectric nanoparticles into the PVDF membrane further enhanced the pollutant removal efficiency. We propose that the enhanced adsorption arises from the synergistic effects of the porous structure, low surface energy, and ultrasound-induced polarization. This strategy may strengthen the functionality of PVDF-based filtration to reduce pressure on upstream and downstream processes, and shed light on the development of multifunctional materials for separation technologies.