Self-assembling/electrostatic spraying synergistically modified PET-based fiber for highly efficient removal of airborne particulate matter and bacteria

The issue of air pollution, encompassing airborne bacteria and particulate matter (PM), has emerged as a prominent concern impacting human comfort and health. However, conventional air filtration materials fail to meet the requirements for efficient PM capture or immediate bacteria elimination, thereby heightening the risk of contracting diseases due to pollutant accumulation during filtration. Herein, the hydroxyl group in cellulose acetate (CA) was used as the nucleation site to facilitate the self-assembly of Cu-MOF crystals on PET substrate through hydrogen bonding, and then a layer of PVDF-HFP was electrostatically sprayed to finally obtain the high-efficiency and low-resistance PET/CA-MOF-PH air filtration material. On the one hand, the PET/CA-MOF-PH filter material exhibits outstanding filtration performance (99.82 % for PM1.0, 99.93 % for PM2.5, and 99.99 % for PM10) and a low-pressure drop (62 Pa) due to the highly dispersed and dense micro- and nanostructures of the surface layers of the filter material. On the other hand, benefitting from Cu 2+ in the Cu-MOF crystals, PET/CA-MOF-PH filter material also performs excellently in bacterial killing. The filtration capacity difference between commercial PET fibers and PET/CA-MOF-PH filter media at various wind speeds was further investigated through dynamic particle capture simulation and airflow field distribution analysis. This study thus suggests that PET/CA-MOF-PH with high filter efficiency, low resistance, and excellent antibacterial activity designed by self-assembly/electrostatic spraying strategy is expected to be an ideal material for air filters, and this strategy can guide the rational design of multifunctional novel filter materials suitable for environmental and energy fields.