Preparation and photocatalytic and antibacterial properties of polyvinyl alcohol/chitosan/TiO2@Ag electrospun nanofibers

Abstract

Polyvinyl alcohol (PVA) is a widely used polymer in the electrospinning technique. It is water-soluble, which limits the application of electrospun PVA matrix. In this study, chitosan (CS) and biosynthesized TiO2@Ag nanoparticles were incorporated into PVA to enhance its antibacterial properties and photocatalysis. The PVA/CS/TiO2@Ag nanofiber mat was prepared using the electrospinning method with a voltage of 20 kV, a needle-collector distance of 15 cm, and a flow rate of 0.5 mL.h−1. The concentrations of the PVA and CS solutions were 10% and 2%, respectively. The TiO2@Ag nanoparticles were synthesized using AgNO3 solution, TiO2 nanoparticles as precursors, and Cleistocalyx operculatus leaf extract as a reducing agent. The morphology and structure of the PVA/CS/TiO2@Ag nanofiber mat were analyzed using scanning electron microscopy and infrared spectroscopy. The PVA/CS/TiO2@Ag nanofibers exhibited an average fibril diameter of 116.4 nm. Additionally, the antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), as well as the photocatalytic properties of these mats, were assessed. The results indicated that the addition of CS and TiO2@Ag led to changes in the hydrophilic properties and antibacterial efficacy of PVA. The inhibition zones of the PVA/CS/TiO2@Ag nanofiber mat against E. coli and S. aureus were measured at 5 and 4 mm, respectively. The water contact angle of PVA/CS/TiO2@Ag nanofiber mat showed a significant increase. The PVA/CS/TiO2@Ag nanofibers were able to degrade 94.56 ± 0.57% and 98.17 ± 0.11% of methylene blue dye under sunlight irradiation after 10 and 20 min of exposure, respectively. These findings suggest that the PVA/CS/TiO2@Ag nanofiber mat has the potential for applications in the textile industry or medicinal field as antibacterial and photocatalytic coatings.