Preparation of modified halloysite nanotubes@Ag3PO4/polyacrylonitrile electrospinning membranes for highly efficient air filtration and disinfection

Abstract

Particulate matters (PMs) and airborne bacteria are among the most severe indoor air issues due to their substantial implications for human health. Therefore, it was imperative to conduct a comprehensive investigation on air filtration materials with superior filtration performance and antibacterial properties. Here, the m-Hal@Ag3PO4 composite particles were prepared by using modified halloysite nanotubes (m-Hal) as the support of Ag3PO4 nano-photocatalysts. These composite antibacterial particles were uniformly dispersed within a polyacrylonitrile (PAN) solution and were subsequently electrospun into m-Hal@Ag3PO4/PAN composite nanofiber membranes (CNMs) possessing excellent antibacterial properties. The incorporation of 30 wt% m-Hal@Ag3PO4 additionally enhanced the filtration efficiency of PM0.3 to 99.9%, at an airflow rate of 32 L/min, while concurrently reducing the pressure drop by 36.7%. The photocatalytic degradation efficiency of CNMs towards ciprofloxacin reached 99%. The antibacterial experiments demonstrated that CNMs exhibited potent antibacterial activity against both Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli)under dark and light conditions. Under visible light irradiation, the average diameter of the inhibition zone for the composite membrane surpassed that observed under dark conditions, indicating a predominant enhancement in its antibacterial efficacy through photocatalysis. The enhanced photocatalytic performance and excellent stability can be attributed to the incorporation of Ag3PO4 with m-Hal, which enhanced the dispersibility and facilitated efficient carrier separation of Ag3PO4. The present type of CNMs exhibited the advantages of high efficiency and low resistance air filtration, photodegradation ability, and recyclability, thereby enhancing the efficacy and lifespan of PMs filtration, bacteria disinfection, and antibiotic degradation. This offered a novel concept and viable approach for indoor air and water purification based on electrospinning technology.