Highly Transparent Superhydrophobic Surfaces from the Coassembly of Nanoparticles (≤100 nm)

Abstract

We report a simple and versatile approach to creating a highly transparent superhydrophobic surface with dual-scale roughness on the nanoscale. 3-Aminopropyltrimethoxysilane (APTS)-functionalized silica nanoparticles of two different sizes (100 and 20 nm) were sequentially dip coated onto different substrates, followed by thermal annealing. After hydrophobilization of the nanoparticle film with (heptadecafluoro-1,1,2,2-tetrahydrodecyl)trichlorosilane for 30 min or longer, the surface became superhydrophobic with an advancing water contact angle of greater than 160° and a water droplet (10 μL) roll-off angle of less than 5°. The order of nanoparticles dip coated onto the silicon wafer (i.e., 100 nm first and 20 nm second or vice versa) did not seem to have a significant effect on the resulting apparent water contact angle. In contrast, when the substrate was dip coated with monoscale nanoparticles (20, 50, and 100 nm), a highly hydrophobic surface (with an advancing water contact angle of up to 143°) was obtained, and the degree of hydrophobicity was found to be dependent on the particle size and concentration of the dip-coating solution. UV-vis spectra showed nearly 100% transmission in the visible region from the glass coated with dual-scale nanoparticles, similar to the bare one. The coating strategy was versatile, and superhydrophobicity was obtained on various substrates, including Si, glass, epoxy resin, and fabrics. Thermal annealing enhanced the stability of the nanoparticle coating, and superhydrophobicity was maintained against prolonged exposure to UV light under ambient conditions.

Growth and Migration of BALB/3T3 Fibroblast Cells on Nano-engineered Silica Beads Surface

“…Hydroxyl groups of the glass coverslip reacted with ethoxysilane groups of the TESPSA molecules to form covalent bonds between the glass coverslip and the TESPSA molecules. 28 The amine groups of APTMS-treated silica beads reacted with acid anhydride groups of the TESPSA coated coverslip to form amide bonds in the presence of a catalytic amount of N,N-diisopropylethylamine. As a result, the silica beads were immobilized on the TESPSA coated coverslip by the formation of covalent bonds.…”

“…APTMS-treated silica beads were selectively immobilized on the TESPSA treated regions (Figure 3(a)). 28 Microscopic images of patterned BALB/3T3 fibroblast cells cultured on the silica patterns for 24 h are shown in Figure 3. When cells were added to the modified glass coverslip, they preferentially attached, spread, and proliferated on the regions of silica beads.…”

The Synthesis and Morphology of a Perfluoroalkyl Oligosiloxane@SiO2 Resin and Its Performance in Anti-Fingerprint Coating

“…In synthesizing FSi@SiO2, the bigger the nanoparticles combined in the resin, the rougher of the coating fabricated from the FSi@SiO2 [21]. However, the big nano particles have an unfavorable impact on the transmittance and smoothness of the coating, especially as the big particles load on the perfluoro oligosiloxane coating surface.…”

Effect of time and of precursor molecule on the deposition of hydrophobic nanolayers on ethyelene tetrafluoroethylene–silicon oxide substrates

“…In particular, this technique was applied by means of alkylsilanes and (fluoro)alkylsilanes deposition on glass substrates (Altavilla and Ciliberto 2011) and successfully allowed to obtain hydrophobic surfaces. Other methods, that are employed to achieve superhydrophobicity, are based on the introduction of a two-scale roughness (micrometric and nanometric scales), together with chemical functionalization (Xiu et al 2008;Ling et al 2009;McConnell et al 2009;Karunakaran et al 2011). Although the related works report interesting results in terms of achieved hydrophobicity, they are likely to turn out to be complex and expensive when implemented at industrial level since the proposed methods are based on multi-step processes requiring nonconventional technologies and including high-temperature stages.…”