A Novel Method for Fabricating an Electrospun Poly(Vinyl Alcohol)/Cellulose Nanocrystals Composite Nanofibrous Filter with Low Air Resistance for High-Efficiency Filtration of Particulate Matter

Particulate matter (PM) air pollution poses a risk to public health, especially in rapidly industrializing countries. One major way to protect individuals from PM exposure is to use fiber-based filters for indoor air purification. In this study, a new low pressure drop poly(vinyl alcohol) (PVA)/cellulose nanocrystals (CNCs) composite nanofibrous filter was fabricated using electrospinning. This electrospun PVA/CNCs filter was demonstrated as an air filter for the first time. The CNCs not only contributed to the PVA/CNCs system as mechanical reinforcement agents but also increased the surface charge density of the electrospinning solution, thereby reducing fiber diameter. The thinner fibers reduced pressure drop significantly and increased the efficiency of PM removal. Our results indicate that high PM2.5 removal efficiency was achieved (99.1%) under extremely polluted conditions (PM2.5 mass concentration > 500 mu g m(-3)) with low pressure drop (91 Pa) at an airflow velocity of 0.2 m s(-1). Considering that PVA and CNCs are both nontoxic and biodegradable, this high-efficiency composite filter with low air resistance is environmentally friendly and shows promise in indoor air purification applications.