Inorganic-organic nanofiber networks with antibacteria properties for enhanced particulate filtration: The critical role of amorphous titania

Abstract

The demand for air filter media at indoor and outdoor is increasing tremendously due to air pollution and especially for problems related to airborne particulate matter (PM). To realize that, here a class nanofiber air filter media with strong antibacterial activity, hydrophobic nature, high filtration efficiency with low pressure drop is prepared. Novel organic-inorganic nanocomposite nanofibers used in this work benefited for the multifunctional performance. Amorphous titanium dioxide (mTiO2) is utilized for air filtration application which exhibits excellent enhancement of PM2.5 filtration properties and antibacterial activity. The unique Poly (vinylpyrrolidone) (PVP)-mTiO2 nanofiber air filter media acquired hydrophobic nature with a large increase in water contact angle of 127° from 36°. The resulting free-standing nanofiber filters exhibit high PM2.5 filtration efficiency of >99.9% and low pressure drop of 39 Pa. Antibacterial activity of nanofibrous membrane has been rationally engineered by titanium oxide as the barrier to bacterial ingression. A long term of 160 h filtration test has proved PVP-mTiO2 nanofibers air filter media holds outstanding 99% filtration efficiency for PM2.5. This work takes forward a significant lead in design and production of high performance and very low pressure drop air filter media with a wide range of functional properties.