Electrospun Nanofibers with Antibacterial and Antioxidant Activities for Air Purification

Abstract

The demand for air filtration products has surged as air pollution worsens daily, particularly during the pandemic wave. Traditional air filters frequently require replacement because of the rapid dispersion of electrostatic charge and the buildup of harmful microorganisms. According to the World Health Organization, the majority of deaths related to air pollution are caused by noncommunicable diseases. To tackle these challenges, we have performed a centrifugal spinning experiment under controlled conditions, maintaining a temperature of 21 ± 5 °C and humidity below 36 ± 5%, with the nozzle positioned 10 cm from the collector. Nanofibrous membranes PZCR and PCCR were fabricated using an electrospinning method that offers strong antibacterial properties, effective air filtration, and the ability to be reused. These membranes consist of PAN nanofibers doped with ZnO and Cu nanoparticles and coated with a chitosan solution containing the antibacterial compound. Further, characterization was done by using FESEM, AFM, FTIR, and EDX spectroscopy. The average diameter of the PAN nanofiber before doping was 153 to 184 nm, and after doping, ZnO and Cu NPs were 225 ± 5 nm and 455 ± 5 nm, respectively. There is nearly no impact on the filtering efficiency and percentage of air resistance of the nanofiber mats, even after being treated with isopropyl alcohol, confirming compliance with ISO 16890. The membranes demonstrated a 99.9% bactericidal rate against Escherichia coli and Staphylococcus aureus bacteria, as confirmed by the ruptured bacterial cell membranes. The significant surface area relative to their volume, customizable porous structure, and ease of preparation, electrospun nanofibers make the material an ideal candidate for filtration materials, attracting significant interest in air filtration applications. Furthermore, the straining potential of these sheets remains nearly at the initial level after simple washing, outperforming commercial-grade filters.