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1.
Compared to superhydrophobic surfaces, superamphiphobic surfaces possess more potential applications but are difficult to fabricate. Herein, to address this problem, we describe a simple method to fabricate a superamphiphobic surface based on a CNTs–SiO2 hybrid material. The CNTs–SiO2 hybrid material obtained by a sol–gel approach was sprayed onto glass slides to form coatings. After surface fluorination, the sprayed coating displayed superamphiphobicity toward water and a number of organic liquids, such as dodecane. It was found that the time of fluorination slightly influenced the surface wettability of the sprayed coating. We also investigated the role of CNTs and SiO2 on superamphiphobicity establishment separately, and such information allowed us to engineer surfaces with specific wettability.  相似文献   

2.
J. Yi  X.D. He  Y. Li 《Applied Surface Science》2007,253(17):7100-7103
SiC/SiO2 nanocomposite coating was deposited by electron beam-physical vapor deposition (EB-PVD) through depositing SiC target on pre-oxidized 316 stainless steel (SS) substrate. High melting point component C remained and covered on the surface of ingot after evaporation. When SiC ingot was reused, remaining C had an effect on the composition, hardness and emissivity of SiC/SiO2 nanocomposite coating. The composition of ingot and coating was studied by X-ray photoelectron spectroscopy (XPS). The influence of remaining C on hardness and spectral normal emissivity of SiC/SiO2 nanocomposite coating was investigated by nanoindentation and Fourier transform infrared spectrum (FTIR), respectively. The results show that remaining C has a large effect on hardness and a minor effect on spectral normal emissivity of SiC/SiO2 nanocomposite coating.  相似文献   

3.
Superhydrophobic poly(methyl methacrylate)-SiO2 (coded as PMMA-SiO2) nanocomposite films with micro-nanohierarchical structure were prepared via a simple approach in the absence of low surface-energy compounds. By spin-coating the suspension of hydrophobic silica (SiO2) nanoparticles dispersed in PMMA solution, target nanocomposite films were obtained on glass slides. The wetting behavior of PMMA-SiO2 nanocomposite films was investigated in relation to the dosage of SiO2 nanoparticles dispersed in PMMA solution. It was found that hydrophilic PMMA film was transferred to superhydrophobic PMMA-SiO2 nanocomposite films when hydrophobic SiO2 nanoparticles were introduced into the PMMA solution at a high enough dosage (0.2 g and above). Resultant PMMA-SiO2 nanocomposite films had a static water contact angle of above 162°, showing promising applications in selfcleaning and waterproof for outer wall of building, outer covering for automobile, sanitary wares, and so forth.  相似文献   

4.
Herein, we report a facile and low cost method for the fabrication of superhydrophobic surface via spin coating the mixture of polydimethylsiloxane precursor (PDMS) and silicon dioxide (SiO2) nanoparticles. The surface hydrophobicity can be well tuned by adjusting the weight percent of PDMS and SiO2. The water contact angle (WCA) can increase from 106.8 ± 1.2° on PDMS film to 165.2 ± 2.3° on PDMS/SiO2 coating, companying with a change from adhering to rolling which was observed from tilting angle (TA) characterization. Multi-scale physical structures with SiO2 nanoparticle aggregates and networks of SiO2 nanoparticle aggregates are characterized by scanning electron microscopy (SEM) and atomic force microscope (AFM), and they can be observed more clearly from the AFM images treated with software (WSxM). Then the relationship between surface hydrophobicity and structures is further discussed based on Wenzel and Cassie models, indicating that the appearance of networks of nanoparticle aggregates is important in the Cassie state. The superhydrophobic coating can keep the superhydrophobicity at least for one month under environment conditions and readily regenerate after mechanical damage. Additionally, the superhydrophobic coating can be fabricated using other methods including dip coating, spray coating and casting. Thus, a large area of superhydrophobic coatings can be easily fabricated. Therefore the range of possible applications for these facile and versatile methods can be expanded to various actual conditions.  相似文献   

5.
Superhydrophobic thin films were prepared on glass by air-brushing the in situ polymerization compositions of D5/SiO2. The wettability and morphology were investigated by contact angle measurement and scanning electron microscopy. The most superhydrophobic samples prepared had a static water contact angle of 157° for a 5 μl droplet and a sliding angle of ∼1° for 10 μl droplet. Thermal stability analysis showed that the surface maintained superhydrophobic at temperature up to 450 °C. Air trapping and capillary force on superhydrophobic behavior were evaluated.  相似文献   

6.
Advances in materials performance often require the development of composite system. In the present investigation, SiO2-reinforced nickel composite coatings were deposited on a mild steel substrate using direct current electrodeposition process employing a nickel acetate bath. Surface morphology, composition, microstructure and crystal orientation of the Ni and Ni-SiO2 nanocomposite coatings were investigated by scanning electron microscope, energy dispersive X-ray spectroscopy and X-ray diffraction analysis, respectively. The effect of incorporation of SiO2 particles in the Ni nanocomposite coating on the microhardness and corrosion behaviour has been evaluated. Smooth composite deposits containing well-distributed silicon oxide particles were obtained. The preferred growth process of the nickel matrix in crystallographic directions <111>, <200> and <220> is strongly influenced by SiO2 nanoparticles. The average crystallite size was calculated by using X-ray diffraction analysis and it was ~23 nm for electrodeposited nickel and ~21 nm for Ni-SiO2 nanocomposite coatings. The crystallite structure was fcc for electrodeposited nickel and Ni-SiO2 nanocomposite coatings. The incorporation of SiO2 particles into the Ni matrices was found to improve corrosion resistance of pure Ni coatings. The corrosion potential (E corr) in the case of Ni-SiO2 nanocomposite coatings had shown a negative shift, confirming the cathodic protective nature of the coating. The Ni-SiO2 composite coatings have exhibited significantly improved microhardness (615 HV) compared to pure nickel coatings (265 HV)  相似文献   

7.
Plasma-enhanced chemical vapor deposition was used to conformally coat commercial TiO2 nanoparticles to create nanocomposite materials. Hexamethyldisiloxane (HMDSO)/O2 plasmas were used to deposit SiO2 or SiOxCyHz films, depending on the oxidant concentration; and hexylamine (HexAm) plasmas were used to deposit amorphous amine-containing polymeric films on the TiO2 nanoparticles. The composite materials were analyzed using Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). These analyses reveal film composition on the nanoparticles was virtually identical to that deposited on flat substrates and that the films deposit a conformal coating on the nanoparticles. The performance of the nanocomposite materials was evaluated using UV-vis spectroscopy to determine the dispersion characteristics of both SiOx and HexAm coated TiO2 materials. Notably, the coated materials stay suspended longer in distilled water than the uncoated materials for all deposited films.  相似文献   

8.
A SiO2 protective coating was deposited on an IN738LC alloy using CCVD. The physical properties of a SiO2 protective layer are influenced by the amount of tetraethyl orthosilicate (TEOS, C8H20O4Si). Therefore, the SiO2 protective coating was deposited using different TEOS concentrations and deposition times to optimize the conditions. The deposited coating layer was confirmed to be a SiO2 layer by SEM, EDX, and ESCA analyses. The oxidation resistance of the alloy was evaluated by thermo gravimetric analysis. The oxidation resistance of the SiO2 protective coating was highest when the coating was processed at a TEOS concentration of 0.05 mol/l, which is the highest concentration of source material used. The surface roughness of the SiO2 protective layer also increased with increasing TEOS concentration. The surface roughness of the coating had little effect on the oxidation resistance for a film thickness of approximately 1 μm.  相似文献   

9.
Au/SiO2 nanocomposite films were prepared on Si wafers by cosputtering of SiO2 and gold wires. Au/Si atomic ratios in Au/SiO2 nanocomposite films were varied from 0.53 to 0.92 by controlling the length of gold wire to study the evolution of the crystallization of gold, the size of Au/SiO2 nanocomposite particles, and the optical properties of as-deposited Au/SiO2 nanocomposite films. An X-ray photoelectron spectroscopy reveals that Au exists as a metallic phase in the bulk of SiO2 matrix. Dome-shaped Au/SiO2 nanocomposite particles and both Au (1 1 1) and (2 0 0) planes were observed in a field-emission scanning electron microscopy and X-ray diffraction studies respectively. With an ultraviolet-visible, absorption peaks of Au/SiO2 nanocomposite films were observed at 525 nm.  相似文献   

10.
Liquid flame spray process (LFS) was used for depositing TiOx and SiOx nanoparticles on paperboard to control wetting properties of the surface. By the LFS process it is possible to create either superhydrophobic or superhydrophilic surfaces. Changes in the wettability are related to structural properties of the surface, which were characterized using scanning electron microscope (SEM) and atomic force microscope (AFM). The surface properties can be ascribed as a correlation between wetting properties of the paperboard and the surface texture created by nanoparticles. Surfaces can be produced inline in a one step roll-to-roll process without need for additional modifications. Furthermore, functional surfaces with adjustable hydrophilicity or hydrophobicity can be fabricated simply by choosing appropriate liquid precursors.  相似文献   

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