Nanoparticle decorated fibrous silica membranes exhibiting biomimetic superhydrophobicity and highly flexible properties

Abstract

Inspired by the self-cleaning lotus leaf, here we report the fabrication of flexible fluorinated silica nanofibrous membranes with biomimetic non-wettable surfaces by electrospinning blend solutions of poly(vinyl alcohol) (PVA) and silica gel in the presence of silica nanoparticles, followed by calcination and fluoroalkylsilane (FAS) modification. The resultant silica nanofibers exhibited a lotus-leaf-like structure with numerous nanoparticles decorated on the fiber surfaces due to the rapid phase separation in electrospinning and calcination processing. The content of silica nanoparticles incorporated into the fibers proved to be the key factor affecting the fiber surface morphology and wettability. The fluorinated silica fibrous membranes containing 38.8 wt% silica nanoparticle showed the highest water contact angle (WCA) of 155u, oil contact angle (OCA) of 143u, orange juice contact angle (OJCA) of 142u, and milk contact angle (MCA) of 137u. Additionally, the fluorinated silica membranes exhibited good flexibility and the flexibility was also characterized by KES-FB2S. We believe that this new class of inorganic membranes is particularly promising for the development of high-temperature filtration, novel easy-clean coatings, and even flexible electronics.

Electrospun Nanofibers for Air Filtration

“…Over the past decade, considerable effort has been devoted to fabricating ceramic nanofibers, including SiO 2 [73], Al 2 O 3 [74], ZrO 2 [75], and so on; however, the brittleness of current ceramic membranes significantly limits their practical applications. Recently, silica nanofibrous (SNF) membranes with remarkable flexibility and thermal stability were prepared by a facile combination of electrospinning and solgel methods [76][77][78][79]. Figure 12.10a showed the optical image of flexible silica fibrous membranes when bent with poly(ethylene terephthalate) (PET) film, and no crack appeared during the bending [76].…”

Colloid‐Electrospinning: Fabrication of Multicompartment Nanofibers by the Electrospinning of Organic or/and Inorganic Dispersions and Emulsions

“…Magnesium, aluminum, silicon, titanium, iron, zinc, zirconium, and mixed metal oxides nanoparticles were successfully electrospun (Table 3). Silica nanoparticles in fibers were often used to produce superhydrophobic meshes 47–50. Multiple‐scale superhydrophobic materials can be synthesized by electrospinning silica and polystyrene dispersions (Figure 6a) 47, 48, 51.…”

“…The porous fibers were subsequently cut by ultrasound to yield silica rods (Figure 6b) 51. Other authors have introduced a fluorinated chemical on the fibers to induce an additional oleophobicity (Figure 6c) 50. The sizes of the silica particles have a decisive influence on their aggregation state in the electrospun fibers.…”

“…b) silica rods prepared by electrospinning of dispersions of spherical silica and polystyrene nanoparticles, sintering, and sectioning of the fibers 51. c) Photograph of droplets of various liquids on the membrane synthesized by electrospinning of silica dispersions 50. Reproduced with permission.…”

Fabrication of scalable tissue engineering scaffolds with dual-pore microarchitecture by combining 3D printing and particle leaching

“…In the spectrum for PVA, peaks were observed at 3400 cm −1 (− OH) and 1740 cm −1 (CO), whereas salt crystals had a peak at 3400 cm −1 (−OH). All of these peaks were absent in spectrum for cross-linked PDMS due to the different molecular structure [32,33]. The spectrum for the fabricated 3D scaffold (recorded from the interior regions as shown in the Supplementary Fig.…”