Nanofiber Air Filters with High-Temperature Stability for Efficient PM_2.5 Removal from the Pollution Sources

TLDR

The study aims to develop high‑efficiency (>99.5 %) polyimide‑nanofiber air filters for removing PM₂.₅ at high temperatures. They fabricated polyimide nanofiber filters that achieve >99.5 % PM₂.₅ removal across a temperature range of 25–370 °C. The filters maintained >99.5 % removal from 25 to 370 °C, exhibited high air flux with low pressure drop, operated continuously for over 120 h at PM₂.₅ index > 300, and effectively removed >99.5 % particles from car exhaust in field tests.

Abstract

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.