Ultra-fine SiO2 nanofilament-based PMIA: A double network membrane for efficient filtration of PM particles

Alarming levels of particulate matter (PM) in air pose a serious health threat in several countries; therefore, there is a strong need for an economic and viable technology for air filtration. In this work, a facile and green approach is proposed to fabricate a double-network membrane for efficient filtration of fine PM particles. The membrane is composed of binary hierarchical structures, including scaffold poly(m-phenylene isophthalamide) (PMIA) nanofibers, and intertwine ultra-fine SiO2 nanofilaments on its surface. The presence of SiO2 nanofilaments notably changed the morphology, specific surface area and porosity of the pristine PMIA nanofibers without reducing the mechanical strength. The PM capture measurement demonstrates that the hybrid membrane exhibited a significantly better PM capture than the bare PMIA membrane, and the removal efficiencies of PM2.5 and PM10 were 97.33% and 98.48%, respectively.