Biobased Antiviral Nonwoven Mask Filter with High Filtration Performance

Abstract

The COVID-19 pandemic has resulted in an increased demand of functional nonwovens for face mask applications. In this study, biobased nonwoven filters (NWFs) loaded with silver nanoparticles (AgNPs) were developed. The AgNPs were prepared by reducing Ag+ with lignin extracted from Miscanthus × giganteus. The effects of AgNO3 concentration, reaction time, and temperature on AgNP synthesis were studied using UV–vis spectroscopy. The AgNPs were incorporated into ethyl cellulose fibers through electrospinning. The resulting composite fibers were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, and X-ray diffraction. The average diameter of AgNPs was 6.54 ± 2.3 nm, while the bead-free electrosopun fibers had diameters ranging from 153 to 184 nm. The filtration efficiency, pressure drop, and quality factor of the NWFs were tested against NaCl aerosol particles (≥0.3 μm). The NWF samples tested had filtration efficiency of higher than 99%, with pressure drop and quality factor values of 86.20–88.25 Pa and 0.0690–0.0772 Pa–1, respectively. The antiviral properties of the AgNP-loaded NWFs were evaluated against a surrogate virus, Pseudomonas bacteriophage Φ6, resulting in a 5 log10 (PFU/mL) reduction beyond the starting viral titer. This study demonstrated the potential of the antiviral NWFs for high-performance mask filter applications.