Highly efficient particulate matter
(PM) filter membranes with
good resistance to wetting are highly desirable given the negative
environmental impact of increasing PM pollution. In this study, a
self-cleaning and PM-filtering fibrous membrane (F-SAPAN) was prepared
by attaching silica nanoparticles (SiNPs) on the surface of modified
polyacrylonitrile using a sol–gel approach and then adding
a low surface energy 1H,1H,2H,2H-perfluorodecyltrichlorosilane (FOTS)
coating. The SiNPs were generated by the hydrolysis of tetraethyl
orthosilicate and could be readily loaded on the surface of the fiber,
thanks to hydrogen bonding. In this way, fibrous membranes with a
uniform covering of SiNPs could be prepared in large quantities in
a short time. The modification of SiNPs by FOTS endows the fibrous
membrane with excellent water and oil resistance (a water contact
angle of up to 156° and an oil contact angle of up to 144°),
and the free-rolling of water droplets can be achieved on a slope
of only 6°. The membrane is only 0.03 mm thick and displays excellent
filtration efficiency (>99.9%) and pressure drop (366.4 Pa) for
PM1. The membranes also display good flexibility, mechanical
properties, corrosion resistance, and antiash properties and prove
to be a reliable material for PM filtration in complex environments.