The Experts below are selected from a list of 16488 Experts worldwide ranked by ideXlab platform
Qihua Wang - One of the best experts on this subject based on the ideXlab platform.
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UV-Driven Reversible Switching of a Polystyrene/Titania Nanocomposite Coating between Superhydrophobicity and Superhydrophilicity
Langmuir, 2009Co-Authors: Weixin Hou, Qihua WangAbstract:Hydrophilic Titania (Tio2) nanoparticles were dispersed in solutions of polystyrene (PS), and the suspensions were cast on glass surfaces. The effect of drying temperature on the hydrophobic character of PS/Tio2 was investigated: the static water contact angle increased with the drying temperature, and the as-prepared coating could be adjusted from superhydrophilicity to superhydrophobicity just by controlling the drying temperature. Moreover, the superhydrophobic coating turning into a superhydrophilic one (CA < 5°) after UV illumination, which can be recovered through being heated.
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uv driven reversible switching of a polystyrene Titania nanocomposite coating between superhydrophobicity and superhydrophilicity
Langmuir, 2009Co-Authors: Qihua WangAbstract:Hydrophilic Titania (Tio2) nanoparticles were dispersed in solutions of polystyrene (PS), and the suspensions were cast on glass surfaces. The effect of drying temperature on the hydrophobic character of PS/Tio2 was investigated: the static water contact angle increased with the drying temperature, and the as-prepared coating could be adjusted from superhydrophilicity to superhydrophobicity just by controlling the drying temperature. Moreover, the superhydrophobic coating turning into a superhydrophilic one (CA < 5°) after UV illumination, which can be recovered through being heated.
Kuan-pin Chen - One of the best experts on this subject based on the ideXlab platform.
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Preparation and characterization of poly(imide siloxane) (PIS)/Titania(Tio2) hybrid nanocomposites by sol–gel processes
European Polymer Journal, 2007Co-Authors: Wen-chang Liaw, Kuan-pin ChenAbstract:Abstract Poly(imide siloxane)(PIS)/Titania(Tio2) hybrid nanocomposites with organic–inorganic covalent bonding have been successfully synthesized by sol–gel processes. The PIS copolymer synthesized in this study was characterized by the observed coexisting two segments: the polyimide (PI) segment and polydimethyldiphenylsiloxane segment, and the latter were specially featured with the introduction of a diphenyl group for improved homogeneity. The obtained Tio2 networks in PIS matrix were well dispersed and their average diameter was less than 50 nm. Meanwhile, the PIS/Tio2 hybrid nanocomposite films exhibited good optical transparency at 20 wt% of Tio2 content. The thermal stability, tensile strength and elongation of the nanocomposites decreased with increasing Tio2 content. The glass transition temperature (Tg) and Young’s modulus increased with increasing Tio2 content. The chemical structure and morphologies of PIS/Tio2 hybrid nanocomposites was characterized by Fourier transform infrared spectroscope (FT-IR), X-ray photoelectron spectroscopy (XPS), and transmission electron microscope (TEM). The Tg and thermal stability were measured by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA), respectively. The mechanical properties were examined by dynamic mechanical analysis (DMA) under controlled force mode.
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preparation and characterization of poly imide siloxane pis Titania Tio2 hybrid nanocomposites by sol gel processes
European Polymer Journal, 2007Co-Authors: Wen-chang Liaw, Kuan-pin ChenAbstract:Abstract Poly(imide siloxane)(PIS)/Titania(Tio2) hybrid nanocomposites with organic–inorganic covalent bonding have been successfully synthesized by sol–gel processes. The PIS copolymer synthesized in this study was characterized by the observed coexisting two segments: the polyimide (PI) segment and polydimethyldiphenylsiloxane segment, and the latter were specially featured with the introduction of a diphenyl group for improved homogeneity. The obtained Tio2 networks in PIS matrix were well dispersed and their average diameter was less than 50 nm. Meanwhile, the PIS/Tio2 hybrid nanocomposite films exhibited good optical transparency at 20 wt% of Tio2 content. The thermal stability, tensile strength and elongation of the nanocomposites decreased with increasing Tio2 content. The glass transition temperature (Tg) and Young’s modulus increased with increasing Tio2 content. The chemical structure and morphologies of PIS/Tio2 hybrid nanocomposites was characterized by Fourier transform infrared spectroscope (FT-IR), X-ray photoelectron spectroscopy (XPS), and transmission electron microscope (TEM). The Tg and thermal stability were measured by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA), respectively. The mechanical properties were examined by dynamic mechanical analysis (DMA) under controlled force mode.
Subramanyan Vasudevan - One of the best experts on this subject based on the ideXlab platform.
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Eco-friendly and facilely prepared silica modified amorphous Titania (Tio2–SiO2) electrocatalyst for the O2 and H2 evolution reactions
Catalysis Science & Technology, 2015Co-Authors: R. Venkatkarthick, Donald Jonas Davidson, S. Ravichandran, S. Vengatesan, Ganapathy Sozhan, Subramanyan VasudevanAbstract:An eco-friendly silica modified amorphous Titania (Tio2–SiO2) electrocatalyst is prepared. This silica modified amorphous Titania (Tio2–SiO2) composite material is prepared by facile spurting of silica (obtained from a sustainable resource) over a titanium plate and identified as an active electrocatalyst for O2 and H2 evolution by water oxidation. The prepared composite shows a maximum current density of 12 mA cm−2 at 2 V (versus RHE) in 1 M KOH electrolyte. This is because the semiconductor heterostructure of the structurally and chemically dissimilar amorphous Tio2–SiO2 composite introduces new collective electronic states with improved electrical conductivity, with a decrease in the work function. The catalytic activity is found to be stable in continuous operation for about 10 h. The physicochemical characterization of the electrocatalyst was carried out using scanning electron microscopy, energy dispersive X-rays, X-ray diffraction, X-ray photoelectron spectra, and electron paramagnetic resonance and the work function was examined by a Scanning Kelvin Probe. Because of the simple, cheap, and scalable preparation procedure, the electrocatalyst is highly promising for practical low cost and high technology applications. Interestingly, the system is active in the oxygen and hydrogen evolution reactions, leading to a promising bifunctional electrocatalyst.
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eco friendly and facilely prepared silica modified amorphous Titania Tio2 sio2 electrocatalyst for the o2 and h2 evolution reactions
Catalysis Science & Technology, 2015Co-Authors: R. Venkatkarthick, Donald Jonas Davidson, S. Ravichandran, S. Vengatesan, Ganapathy Sozhan, Subramanyan VasudevanAbstract:An eco-friendly silica modified amorphous Titania (Tio2–SiO2) electrocatalyst is prepared. This silica modified amorphous Titania (Tio2–SiO2) composite material is prepared by facile spurting of silica (obtained from a sustainable resource) over a titanium plate and identified as an active electrocatalyst for O2 and H2 evolution by water oxidation. The prepared composite shows a maximum current density of 12 mA cm−2 at 2 V (versus RHE) in 1 M KOH electrolyte. This is because the semiconductor heterostructure of the structurally and chemically dissimilar amorphous Tio2–SiO2 composite introduces new collective electronic states with improved electrical conductivity, with a decrease in the work function. The catalytic activity is found to be stable in continuous operation for about 10 h. The physicochemical characterization of the electrocatalyst was carried out using scanning electron microscopy, energy dispersive X-rays, X-ray diffraction, X-ray photoelectron spectra, and electron paramagnetic resonance and the work function was examined by a Scanning Kelvin Probe. Because of the simple, cheap, and scalable preparation procedure, the electrocatalyst is highly promising for practical low cost and high technology applications. Interestingly, the system is active in the oxygen and hydrogen evolution reactions, leading to a promising bifunctional electrocatalyst.
Zhiqun Lin - One of the best experts on this subject based on the ideXlab platform.
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Freestanding Tio2 nanotube arrays with ultrahigh aspect ratio via electrochemical anodization
Chemistry of Materials, 2008Co-Authors: Jun Wang, Zhiqun LinAbstract:Self-organized, freestanding Titania (Tio2) membrane with ultrahigh aspect ratio of the length/diameter (?1500) was fabricated via electrochemical anodization of highly pure titanium (Ti) foil in fluorine-containing ethylene glycol, followed by a simple and safe detachment of the formed Tio2 membrane from the metallic Ti substrate. The resulting membrane consists of highly ordered, vertically aligned, one-side open Tio2 nanotube arrays. The pore diameter, wall thickness, and length of the nanotube arrays are 90 nm, 15 nm, and 135 µm, respectively, at a certain anodization condition.
Wen-chang Liaw - One of the best experts on this subject based on the ideXlab platform.
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Preparation and characterization of poly(imide siloxane) (PIS)/Titania(Tio2) hybrid nanocomposites by sol–gel processes
European Polymer Journal, 2007Co-Authors: Wen-chang Liaw, Kuan-pin ChenAbstract:Abstract Poly(imide siloxane)(PIS)/Titania(Tio2) hybrid nanocomposites with organic–inorganic covalent bonding have been successfully synthesized by sol–gel processes. The PIS copolymer synthesized in this study was characterized by the observed coexisting two segments: the polyimide (PI) segment and polydimethyldiphenylsiloxane segment, and the latter were specially featured with the introduction of a diphenyl group for improved homogeneity. The obtained Tio2 networks in PIS matrix were well dispersed and their average diameter was less than 50 nm. Meanwhile, the PIS/Tio2 hybrid nanocomposite films exhibited good optical transparency at 20 wt% of Tio2 content. The thermal stability, tensile strength and elongation of the nanocomposites decreased with increasing Tio2 content. The glass transition temperature (Tg) and Young’s modulus increased with increasing Tio2 content. The chemical structure and morphologies of PIS/Tio2 hybrid nanocomposites was characterized by Fourier transform infrared spectroscope (FT-IR), X-ray photoelectron spectroscopy (XPS), and transmission electron microscope (TEM). The Tg and thermal stability were measured by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA), respectively. The mechanical properties were examined by dynamic mechanical analysis (DMA) under controlled force mode.
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preparation and characterization of poly imide siloxane pis Titania Tio2 hybrid nanocomposites by sol gel processes
European Polymer Journal, 2007Co-Authors: Wen-chang Liaw, Kuan-pin ChenAbstract:Abstract Poly(imide siloxane)(PIS)/Titania(Tio2) hybrid nanocomposites with organic–inorganic covalent bonding have been successfully synthesized by sol–gel processes. The PIS copolymer synthesized in this study was characterized by the observed coexisting two segments: the polyimide (PI) segment and polydimethyldiphenylsiloxane segment, and the latter were specially featured with the introduction of a diphenyl group for improved homogeneity. The obtained Tio2 networks in PIS matrix were well dispersed and their average diameter was less than 50 nm. Meanwhile, the PIS/Tio2 hybrid nanocomposite films exhibited good optical transparency at 20 wt% of Tio2 content. The thermal stability, tensile strength and elongation of the nanocomposites decreased with increasing Tio2 content. The glass transition temperature (Tg) and Young’s modulus increased with increasing Tio2 content. The chemical structure and morphologies of PIS/Tio2 hybrid nanocomposites was characterized by Fourier transform infrared spectroscope (FT-IR), X-ray photoelectron spectroscopy (XPS), and transmission electron microscope (TEM). The Tg and thermal stability were measured by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA), respectively. The mechanical properties were examined by dynamic mechanical analysis (DMA) under controlled force mode.