PVDF fiber membrane with ordered porous structure via 3D printing near field electrospinning

Abstract A novel polyvinylidene fluoride (PVDF) fiber membrane with ordered geometric pore structure was fabricated via 3D printing near field electrospinning (NFES) technology. PVDF/SiO2 solution was electrospun into fiber membrane with a series of preset regular geometric pore structure, including triangle, rectangle, hexagon and square, as well as cylindrical pores. The obtained PVDF fiber membrane showed excellent filtration performance with high flux of 1020.7 L m−2 h−1 and particle rejection of 96.7%. (When SiO2 with average size of 50 μm aqueous dispersion was utilized as the feeding solution). Furthermore, the effect of pore geometry (length-to-width ratio of rectangle) on membrane structure and filtration performance were investigated. When the length-to-width ratio increased from 1:1 to 2:1, there was almost 75.5% enhancement of water flux along with a stable particle rejection of >95%. More importantly, the microparticles with different sizes can be sieved and separated using our membranes designed by different preset parameters from AutoCAD. This work demonstrated that membrane's permeation performance could be effectively tuned by designing the pore geometry of membrane. Our PVDF fiber membrane with ordered geometric pore structure has a great promise for precise separation in various separation occasions where pore size can be a problem to comfort.