Dilayer micro/nano Ag/TiO₂ membrane <i>via</i> combining centrifugal spinning and electrospinning for air filtration and sterilization

Particulate matter (PM) and airborne bacteria pose severe environmental and health threats. We developed a safe, economical dilayer membrane combining centrifugal spinning and electrospinning. The outer Ag/TiO₂-embedded polystyrene/cellulose acetate (PS/CA) layer via centrifugal spinning provides antibacterial functionality, while the inner electrospun CA porous layer ensures PM filtration. After the optimization of the preparation parameters of the dilayer membrane, the air filtration efficiency could reach 99.26%, the air resistance was 156.9 Pa, and the antibacterial rates against E. coli and S. aureus were 98.9% and 99.13%, respectively. Importantly, the dilayer membrane strategy can result in significant improvements in performance while maintaining safety and economy. Therefore, the dilayer membrane holds promising potential as a high filtration efficiency and antibacterial air filter in the practical purification of the indoor environment or personal air.