Jet Splitting Enabled One-Step Fabrication of Hierarchically Structured PLA Membranes for High-Performance PM_0.3...

Particulate matter (PM) suspended in the air has posed significant potential threats to human health. However, current air filters designed to intercept PM are confronted with several challenges, including a complicated preparation process, monotonous protective performance, and uncomfortable wearability. Herein, a novel jet-splitting electrospinning strategy was demonstrated to simply fabricate a hierarchically structured PLA membrane with a high filtration performance, antibacterial performance, and rapid heat dissipation for effective and comfortable air filtering. Formulating a cationic antibacterial surfactant in the PLA solution to tailor the splitting of charged jets enables the simultaneous formation of nanofibers, submicron-fibers, and beads in the hierarchical filtration network by the single-jet electrospinning. Benefiting from the synergistic effect of multi-scale fibers and beads, the hierarchically structured filter exhibited an excellent filtration efficiency of 99.979% and high quality factor of 0.45 Pa^-1 against PM_0.3, with a remarkably low pressure drop of 18.7 Pa. Furthermore, the hierarchical structure endowed the filter with excellent stability in filtration performance, even under 20-cyclic and 480 min long-term tests, high-humidity tests with sodium chloride aerosol particles, and the 20-cycle PM_2.5 smoke tests. Simultaneously, the filter also demonstrated remarkable antibacterial performance and an excellent heat dissipation property-all achieved due to its PLA formulation and the hierarchical structure.