Morphology engineering processed nanofibrous membranes with secondary structure for high-performance air filtration

Nanofibers fabricated by electrospinning are attractive in the field of air filtration, but limited by insufficient filtration performance. Furthermore, it still remains a great challenge to regenerate secondary structure in the surface of nanofiber to realize advanced and sustainable filtration. Herein, high-performance, ecofriendly and biosafety polyvinyl alcohol/sodium alginate/hydroxyapatite (T-PVA/SA/HAP) nanofiber with hierarchical structure are fabricated by green electrospinning and thermal treatment. Based on the morphology-modification strategy, a unique wrinkled helical structure (UWHS) is created after thermal treatment and promotes the physical interception for particulate pollutants. Moreover, owing to the electrostatic adsorption effect of HAP nanoparticle, the ability of nanofibrous membranes for capturing PM is further improved (Removal more than 99% for PM0.3-2.5). This work provides novel strategy and insight into development of high-efficiency particulate filtration materials by morphology engineering.