Superhydrophobic Multi-Scale ZnO Nanostructures Fabricated by Chemical Vapor Deposition Method

Abstract

The ZnO nanostructures were synthesized on Si(100) substrates by chemical vapor deposition (CVD) method. Different Morphologies of ZnO nanostructures, such as nanoparticle film, micro-pillar and micro-nano multi-structure, were obtained with different conditions. The results of XRD and TEM showed the good quality of ZnO crystal growth. Selected area electron diffraction analysis indicates the individual nano-wire is single crystal. The wettability of ZnO was studied by contact angle admeasuring apparatus. We found that the wettability can be changed from hydrophobic to super-hydrophobic when the structure changed from smooth particle film to single micro-pillar, nano-wire and micro-nano multi-scale structure. Compared with the particle film with contact angle (CA) of 90.7 degrees, the CA of single scale microstructure and sparse micro-nano multi-scale structure is 130-140 degrees, 140-150 degrees respectively. But when the surface is dense micro-nano multi-scale structure such as nano-lawn, the CA can reach to 168.2 degrees . The results indicate that microstructure of surface is very important to the surface wettability. The wettability on the micro-nano multi-structure is better than single-scale structure, and that of dense micro-nano multi-structure is better than sparse multi-structure.

Packing the Silica Colloidal Crystal Beads: A Facile Route to Superhydrophobic Surfaces

“…Studies have revealed that the lotus leaf consists of many microscale papillae, which are decorated with nanometer-scale protrusions. , Generally, this unique property originates from surface roughness caused by micro- and nanoscale papillae and the epicuticular wax. − On the basis of the above understanding, an artificial superhydrophobic surface can be achieved by fabricating dual-scale roughness structure on the substrate surface area and tuning surface energy. Inspired by this, several techniques for fabrication of biomimic superhydrophobic surfaces have been developed, including microstructured polymer samples produced by plasma treating, , a two-length-scale simultaneous patterning on silicon surfaces produced by femtosecond pulsed laser etching, − microstructured superhydrophobic metal and semiconductor surfaces produced by electrochemical deposition, − hierarchical assembled polymeric films produced by layer-by-layer (LBL) methods, − nanoparticle/nanofiber composites and nanofibrous polymeric structures produced by electrospinning techniques, − nanoparticle arrays produced by colloidal monolayer templating or soft-lithography and solution-dipping methods, − and multiscale metal oxide nanostructures produced by chemical vapor deposition methods. , However, because of the special requirements for the substrate, many approaches are limited to fundamental research, rather than practical applications. For example, plasma treating is more suitable for polymeric substrates, the LBL technique can only be applied to polyelectrolyte-coated substrates, and conducting substrates are necessary for the electrochemical deposition method.…”

Fabrication of a Conjugated Fluoropolymer Film Using One-Step iCVD Process and its Mechanical Durability

“…This surface can be obtained using a combination of the topographical properties of the surface texture and the chemical properties of low surface energy. To demonstrate this, Zhou et al have synthesized nanostructured ZnO film with super-hydrophobicity using a chemical vapor deposition (CVD) method [13].…”

Water induced protonation of amine-terminated micelles for direct syntheses of ZnO quantum dots and their cytotoxicity towards cancer

“…Recently, various shapes of ZnO nanostructures have been synthesized, such as nanorods, 7 nanowires, 8 nanotowers, 9 nanowhiskers, 10 nanofibers, 11 nanoplate-nanorod junctions, 12 nanotubes, 13 nanohelices, 14 nanobowls 15 and nanosheets. 16 Many traditional methods have been employed for fabrication of ZnO nanostructures, including thermal evaporation, 17 chemical vapor deposition, 18 template-based synthesis, 19 hydrolysis, 20 electrodeposition, 21 and hydrothermal 22 or solvothermal 23 treatment. Usually, the strong alkaline environment is indispensable to form the key intermediates, Zn(OH) 4 2À and Zn(NH 3 ) 4 2+ for the growth of ZnO nanostructures at room temperature and in a normal atmosphere.…”