Here, we developed high-efficiency (>99.5%) polyimide-nanofiber air filters for the high temperature PM2.5 removal. The polyimide nanofibers exhibited high thermal stability, and the PM2.5 removal efficiency was kept unchanged when temperature ranged from 25-370 °C. These filters had high air flux with very low pressure drop. They could continuously work for >120 h for PM2.5 index >300. A field-test showed that they could effectively remove >99.5% PM particles from car exhaust at high temperature.
Keywords: Air filtration; PM2.5; filter; high temperature; nanofiber; polyimide.