Ultralight electrospun composite filters with vertical ternary spatial network for high-performance PM₀.₃ purification

Abstract

Air pollutants, particularly highly permeable particulate matter (PM), threaten public health and environmental sustainability due to extensive filter media consumption. Existing melt-blown nonwoven filters struggle with PM₀.₃ removal, energy consumption, and disposal burdens. Here, an ultralight composite filter with a vertical ternary spatial network (TSN) structure that saves ≈98% of raw material usage and reduces fabrication time by 99.4%, while simultaneously achieving high-efficiency PM₀.₃ removal (≥99.92%), eco-friendly regeneration (near-zero energy consumption), and enhanced wearing comfort (breathability >80 mm s⁻¹, infrared transmittance >85%), is reported. The TSN filter consists of a hybrid layer of microspheres (average diameter ≈1 µm)/superfine nanofibers (≈20 nm) sandwiched between two nanofiber scaffolds (diameter ≈400 nm and ≈100 nm). This arrangement offers high porosity (≈85%), ultralow areal density (<1 g m⁻²), alow airflow resistance (<90 Pa), guaranteeing superb thermal comfort. Notably, utilizing scalable one-step free surface electrospinning technology, TSN mats can be mass-produced at a rate of 60 meters per hour (width of 1.6 meters), which is critical and verified for various applications including window screens, individual respiratory protectors, and dust collectors. This work provides a viable strategy for designing high-performance nanofiber filter media through structural regulation in a scalable, cost-effective, and sustainable way.