Green fabrication of vertical 3D layered PVA Nanofiber/Submicron fiber membrane for High-Performance particulate filtration

Atmospheric suspended particulate matter capable of long-distance diffusion serves as a carrier for pathogenic microorganisms, posing a persistent threat to public health. However, current high-efficiency filtration materials often suffer from high areal density, poor comfort, and environmental concerns. This study proposes a green and controllable strategy to construct an ultralight (17 mg, low areal density 0.63 g m −2 ) composite fibrous membrane with vertically aligned three-dimensional layered architecture for comfortable, antibacterial, and high filtration performance air filter. This study presents two key innovations: (i) the first-time in situ incorporation of silver nanoparticles onto true nanoscale polyvinyl alcohol (PVA) fibers (∼38 nm) via electrostatic spraying; (ii) the design of an optimal vertical 3D layered structure based on both theoretical and experimental approaches. This design achieves an ultra-low pressure drop (< 70 Pa) while delivering a high PM 0.3 interception efficiency of 99.93 %. To achieve filtration stability, we introduce a natural cinnamaldehyde vapor crosslinking method to improve the water resistance of PVA fibrous membranes, ensuring that the filtration efficiency remains about 99 % even under 75 % relative humidity. Furthermore, benefiting from its retained hydrophilicity and low pressure drop, the material exhibits superior thermal dissipation performance, with a temperature reduction of 3–8 °C compared to commercial face masks. Therefore, this work provides valuable insights into the design of a comfortable, antibacterial, and high-performance PVA-based air filter through a sustainable and environmentally friendly method.