Dual-scale structured cellulose acetate nanofibrous membranes enabling high-efficiency filtration of oily and non-oily PM0.3

With the continuous improvement of living standards, public concern regarding air quality has escalated. Airborne particulate matter (PM), primarily consisting of oily and non-oily particles, presents a significant threat to human health. However, conventional air filtration materials often fail to efficiently capture both categories of particles. In this study, we developed a dual-scale nanofibrous membrane based on cellulose acetate (CA) for the effective filtration of both oily and non-oily PM. Employing a Jet-splitting electrospun strategy, we fabricated a membrane comprising both fine and coarse fibers, endowing it with an ultrafine fiber diameter, a high specific surface area, and a distinctive fibrous architecture. The resulting fibrous air filter exhibited excellent filtration performance for both oily and non-oily PM across varying airflow rates achieving over 99% efficiency at 32 L·min −1 , while maintaining a low pressure drop (123.00 Pa for non-oily PM and 168.89 Pa for oily PM, respectively at this flow rate). The CA dual-scale nanofibrous membrane is straightforward to prepare and holds strong potential for applications in the filtration of cigarette smoke and the purification of air.