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Hydrophobic antireflective coating is fabricated by physical vapor deposition. The optical, contact angle and laser damage resistance properties are investigated, respectively. The transmittance of the antireflective coating with hydrophobic layer is 99.58% at 1064 nm with normal incidence. The contact angle with water is 115.6${}^{\circ }$. The laser damage threshold of the zero probability is 22 J/cm² at 1064 nm with the 12 ns pulse width. This new hydrophobic antireflective coating can be applied in the areas of astronomical optics, laser medical equipment and solar energy, etc.

Molecular interaction dynamics at liquid–liquid interface (LLI), involved nondispersive solution as compared with the interaction in bulk phase. Thereby, interfacial tension (IFT, mN/m) of LLI for four saturated hydrocarbons, six alcohols, and three cationic surfactants are reported at 298.15 K. The pentane, hexane, heptane, octane hydrocarbons and pentanol, hexanol, heptanol, 1-octanol, 2-octanol, and 1-decanol alcohols were used and IFT data were compared with 4 mm kg^-1 dodecyltrimethylammoniumbromide (DTAB), trimethylsulfoxoniumiodide (TMSOI), methyltrioctylammoniumchloride (MTOAC) surfactants studied in benzene–water LLI. The IFT data are noted as hydrocarbons > DTAB > TMSOI > alcohols > MTOAC. The hydrocarbons and alcohols decreased IFT within 16 to 49% and 87 to 92%, respectively, whereas the surfactants within 78.3 to 95.9%. The alcohols developed interaction similar to surfactants and are denoted as nonionic surfactants for making mixtures of low IFT with hydrophilic and hydrophobic interactions to the level of the surfactants. The pentanol and MTOAC caused similar decrease in IFT so the pentanol developed the hydrophilic and hydrophobic interactions of the strength of MTOAC. Comparatively, the hydrocarbons showed lower decrease but the octane showed 49% decrease in IFT. Thus, the hydrocarbon with longer alkyl chain and the alcohol with shorter behave as good surfactants. The hydrocarbons with inductive effect on sigma bond between carbon atoms in alkyl chain also weakened the IFT and influenced the hydrophobic interactions. The MTOAC with four octyl units reduced 96% IFT so inductive effects monitor LLI dynamics.

In this work, we study the hydrophobic properties of silk fabrics by deposition of plasma-polymerized (pp) hexamethyldisiloxane (HMDSO) using low-pressure plasma-enhanced chemical vapor deposition. Recently, hydrophobic properties are under active research in textile industry. The effects of coating time and power on the HMDSO-coated silk fabrics are investigated. Water contact angle of pp-HMDSO-coated silk fabric surface is measured as a function of power and coating time. Fabric surface shows an enhancement in hydrophobicity after coating. Attenuated total reflectance-Fourier transform infrared spectroscopy reveals the surface chemistry, and scanning electron microscopy shows the surface morphology of the uncoated and HMDSO-coated fabrics, respectively. In the case of uncoated fabric, water droplet absorbs swiftly, whereas in the case of HMDSO-coated fabric, water droplet remains on the fabric surface with a maximum contact angle of 140${}^{\circ }$. The HMDSO-deposited silk surface is found to be durable after detergent washing. Common stains such as ink, tea, milk, turmeric and orange juice are tested on the surface of both fabrics. In HMDSO-coated fabrics, all the stains are bedded like ball droplet. In order to study the self-cleaning property, the fabric is tilted to 45${}^{\circ }$ angle; stain droplets easily roll off from the fabric.

With the rapid development of intelligent materials in recent years, intelligent hydrophobic materials have become a new research direction, and hydrophobic surfaces with adjustable wettability have enormous application potential in many fields. Generally speaking, surface wettability is determined by the combined effect of surface chemical composition and surface morphology. Therefore, the photoresponsive wettability of azobenzene-modified surfaces can be achieved by constructing rough surface of micro-nano scale and reducing the surface free energy. In this paper, we synthesized two photo responsive hydrophobic azobenzene derivatives (AAAB-PFDT and UAAB-PFDT), characterized their structure, thermal degradation behavior, and microscopic morphology. The light conversion performance of the two materials in dispersion was also studied using a UV–Vis spectrometer. By depositing the materials on the glass slide, the measurements of the water contact angle (WCA) under different lighting conditions were performed, demonstrating that both materials exhibit excellent photoswitchable hydrophobicity and reversibility.

The anti/de-icing methods are mainly divided into two types: active method and passive method. The passive method generally adopts three ideas: reducing water contact, inhibiting water icing and reducing ice adhesion. Silica aerogels, which have adjustable surface wettability, thermal conductivity and porosity, would be designed to satisfy the requirement for passive anti/de-icing methods. In this work, the organic–inorganic hybrid aerogels based on organosilicon were facilely prepared in a sol–gel procedure, which showed hydrophobic and elastic properties. It could be seen that the thermal insulation effect originating from aerogel-like porous network endowed the efficient anti-icing property. Moreover, the lowest ice adhesion strengths of the above silica aerogels and the related oil-based lubricant-filled aerogels were 7.1kPa and 5kPa, respectively, which belonged to the icephobic surface. Besides, the ice adhesion strength only increased to 15.6kPa after 30 icing–deicing cycles, showing that hydrophobic and elastic silica aerogels had efficient deicing durability.

There is a demand for composite films with excellent hydrophobic properties in inertial confinement fusion (ICF) physics experiments. In this paper, we prepared fluorinated polyimide hydrophobic films using spinning and plasma etching methods. The experimental results indicate that the water contact angle for the perfluorodecyltrichlorosilane (PFTS) treatment polyimide (PI) film is 112.0${}^{\circ }$, which is larger than the pure PI film $(69.0^{\circ })$. The rap oil contact angle is 84.2${}^{\circ }$, which is also much larger than the contact angle of PI film $(12.0^{\circ })$. Moreover, the surface roughness of the prepared films was measured by white light interferometry (WLI). The surface roughness (Ra) of pure PI is 9.79nm, but with the application of FSiO₂ particles, the Ra of the films increases to 65.05nm. After plasma treatment, the Ra of the PI/FSiO₂ composite film increases to 186.71nm because plasma treatment can scratch the film surface and increase its roughness. However, treating the PI/FSiO₂ composite film with the plasma and PFTS, the Ra is only 88.90nm. This decrease in Ra is due to the PFTS, which is able to reduce the surface roughness. The development of composite films, compared to pure PI films, could prove to be an extremely valuable material in ICF experiments.

In this study, CuS/SiO₂ composite modified aerogel was prepared by the incorporation of hollow spherical CuS into methyltrimethoxysilane-based SiO₂ sol and modification with hexadecafluorodecyltriethoxysilane via acid-base catalyzed sol–gel reaction and drying under ambient pressure. The CuS/SiO₂ composite modified aerogel was characterized by Fourier-transform infrared (FT-IR) spectrometry, scanning electron microscope (SEM), nitrogen gas adsorption and desorption and X-ray diffraction (XRD), respectively. The effects of CuS and fluorosilane concentration on density and porosity of aerogel, oleophobic and photocatalytic properties were evaluated. The results showed that structure and physical properties of aerogel had some effect by introducing CuS and fluorosilane, and the CuS/SiO₂ composite modified aerogel with density of 0.146g/cm³ and specific surface area of 241m²/g achieved super-oleophobicity with oil contact angle of 152.8^∘ and sliding angle of 10^∘, and good photocatalytic properties for methylene blue.

A two-step low-temperature hydrothermal method was used to construct an aluminum-nickel compound network structure on the substrate surface, followed by a secondary hydrothermal synthesis of ZnO nanorod array. After low surface energy material modification, a superhydrophobic and superoleophobic surface was obtained. The aluminum-nickel compound network structure plays a key guiding role in the growth of ZnO nanorod arrays. The uniformly shaped and densely arranged ZnO nanorod arrays have high roughness and exhibit excellent hydrophobic properties after modification. The surface of the ZnO nanorod array is improved in terms of UV resistance due to the size effect. The effects of hydrothermal reaction temperature, hydrothermal reaction time, hydrothermal reaction pH value, and Zn${}^{2+}$ concentration on the surface structure, morphology, and properties of the ZnO nanorod array were also studied.

We review the preparation, phase transfer, surface modification and possible bioapplications of hydrophobic CdSe based quantum dots (QDs). CdSe cores with rod and spherical morphologies were prepared through adjusting preparation conditions. The photoluminescence (PL) of the QDs depended strongly on preparation conditions. The QDs were coated with semiconductor shells to improve their PL properties. Anisotropic growth occurred during shell coating. Core/shell QDs revealed tunable PL and high PL efficiencies up to 90%. The phase transfer of QDs from oil phase to water phase was carried out via polymer or a sol–gel process. The silanization of the QDs plays an important role for the sol–gel process. Because of a SiO₂ coating, the surface modification of the QDs for bioapplications became easy. After transferring into water phase, the QDs still retained high PL efficiency. Because of their high PL, these biofunctional materials could provide a platform for various applications.

A simple nonaqueous reaction scheme for transforming the surface of plastics from hydrophobic to hydrophilic is presented. The chemical modification is achieved by the base-catalyzed trans-esterification of polyethylene terephthalate (PET), which is a commonly used plastic. Its use in blood collection tubes is discussed. The surface modification is permanent, inexpensive, rapid, and does not release contaminants. It also causes no optical or mechanical distortion of the plastic. This work demonstrates the power of chemistry to transform common materials.

Nature offers an astonishing array of complex structures and functional devices. The most sophisticated examples of functional systems with multiple interconnected nano-scale components can be found in biology. Biology uses a limited number of building blocks to create complexity and to extend the size and the functional range of basic nano-scale structures to new domains. Three main groups of molecular tools used by biology include oligonucleotides (linear chains of nucleotides), proteins (folded chains of amino acids), and polysaccharides (chains of sugar molecules). Nature uses these tools to store information, to create structures, and to build nano-scale machines.

Recent advances in understanding the structure and function of these building blocks has enabled a number of novel uses for them outside the biological domain. Of particular interest to us is the use of these building blocks to self-assemble nano-scale electronic, photonics, or nanomechanical systems. In this chapter we will look at two groups of building blocks (oligonucleotides and proteins) and review how they have been used to self-assemble engineered structures and build functional devices in the nano-scale.

We will begin by a review of the basic structure and properties (both physical and chemical) of oligonucleotides and proteins. This section is meant to be used as a self-contained reference for the readers from the engineering community that may be less familiar with the symbols and jargon of biochemistry. The most salient properties of the biomolecules are emphasized and listed here to facilitate future research in the area. We continue by a review of recent advances in designing artificial nano-scale DNA structures that can be constructed entirely via engineered self-assembly. Rapid advances in the design and construction of self-assembled DNA structures has resulted in an impressive level of understanding and control over this type of nano-scale manufacturing. Polypeptides and proteins are decidedly less understood and their use in engineered self-assembly has been relatively limited. Nevertheless, as we discuss in the concluding sections of the chapter, both genetically engineered polypeptides and proteins can be used to guide self-assembly processes in nano-scale and help in interfacing nano-scale objects with micron-scale components and templates.

Self-assembled-monolayer (SAM) has a special characteristic that it can template the growth of inorganic crystals under the ordinary conditions, which is similar to the action in the living bodies. In the present study, the precipitation of apatite on "OH" terminated SAM surface(silicon) was observed after soaked in SBF (Simulated Body Fluid). On the contrary, little apatite was formed on the SAM surface with "Phenyl" headgroups. PTCS (Phenyltrichlorosilane) was employed to make "Phenyl" terminated hydrophobic SAM . After UV irradiation for 2 hours, "-OH" terminated hydrophilic SAM was obtained. The effects of such factors as pH and Ca/P molar ratio in SBF solution, soaking temperature and time .etc, on the crystallization of apatite were investigated. XRD results revealed the preferentially oriented crystallization of apatite on "OH" terminated SAM.

A simple nonaqueous reaction scheme for transforming the surface of plastics from hydrophobic to hydrophilic is presented. The chemical modification is achieved by the base-catalyzed trans-esterification of polyethylene terephthalate (PET), which is a commonly used plastic. Its use in blood collection tubes is discussed. The surface modification is permanent, inexpensive, rapid, and does not release contaminants. It also causes no optical or mechanical distortion of the plastic. This work demonstrates the power of chemistry to transform common materials.