Versatile high-temperature air purification with durable, breathable electrostatic filters for ultra-efficient particle capture

Particulate emissions from high temperature pose a significant threat to air quality, necessitating advanced air filtration materials capable of withstanding extreme temperatures and complex environmental conditions. Here, we report a high-efficiency and high-temperature resistant polyimide/SiO 2 (PI/SiO 2 ) nanofiber membrane with excellent air permeability (146 mm/s) and electrostatic effects (−1500 V), fabricated via multi-needle electrospinning followed by thermal imidization. Interface regulation through SiO 2 incorporation enhances the membrane's permeability by expanding fiber spacing and increasing tortuosity, thereby prolonging particle-fiber collision time and improving passive filtration performance. The PI/SiO 2 fibers also generate self-sustained electrostatic charges through friction with air and inter-fiber contact, imparting active filtration capability. By controlling and increasing the SiO 2 content at a constant spinning amount, a balance between filtration efficiency and pressure drop was achieved through enhanced air permeability. Under continuous filtration at 260 °C for 240 min, the membrane exhibited exceptional PM0.3 filtration efficiency (99.1668 %) with a modest pressure drop (109 Pa). Furthermore, by integrating electrospun membranes with filter bags and conducting industrial dust simulations, it achieved an ultrahigh filtration efficiency of 99.9993 % with a pressure drop of only 133 Pa. The successful development of PI/SiO 2 nanofiber membranes provides a promising strategy for next-generation high-temperature-resistant air filters.