Development of a Two‐Tier Fibrous Membrane by Sequential Electrospinning for Effective Air Filtration

Abstract

In the current work, a strategy to fabricate two‐tier structured poly l‐lactide/TiO2 nanoparticles (NPs) incorporated polyvinylpyrrolidone (PLLA/PVP‐TiO2 NPs) fibrous membrane for air filtration via sequential electrospinning technique are reported. Anatase TiO2 NPs ranging from 90 to 105 nm in size were synthesized by the sol–gel method. The diameter of PLLA and PVP‐TiO2 NPs fibers was in the range of 1.15–1.45 and 1.8–2.2 μm, respectively. This two‐tier membrane possessed thermal stability with decomposition temperatures at 364.2 and 447.5 °C for PLLA and PVP‐TiO2, respectively. Gas molecules such as CO, CO2, O2, hydrocarbon (HC) and particulate matter (PM) were adsorbed on the surface of TiO2 nanoparticles as confirmed by IR spectroscopy. The gas adsorption results revealed that 89% of CO2, 80% of CO, 64% of O2, 92% of HC, and 79% of PM were adsorbed after filtration. The pressure drop across the membrane increased from 265 to 341 Pa after filtration. The dust‐loading capacity was quantified by weighing the membrane at regular intervals after exposing it to the exhaust. Adsorption of gases followed the pseudo‐second order kinetic model and intraparticle diffusion mechanism. This two‐tier membrane may be an efficient air filter for domestic and industrial purposes.