Results 101 to 110 of about 329 (124)

Synthesis of High Surface Area Phosphosilicate Glasses by a Modified Sol−Gel Method

Chemistry of Materials, 2005
High surface area phosphosilicate glasses were synthesized by a new sol−gel method and characterized for structural, textural, and acid properties by X-ray diffraction, thermogravimetry/differential thermal analysis, IR spectroscopy (Fourier transform and diffuse reflectance Fourier transform), solid state 31P and 29Si NMR spectroscopy, N2 adsorption ...
ARONNE, ANTONIO, TURCO, MARIA, BAGNASCO, GIOVANNI, PERNICE, PASQUALE, DI SERIO, MARTINO, N. J. Clayden, MARENNA, Elisa, FANELLI, Esther   +7 more
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Sol–gel produced sodium calcium phosphosilicates for bioactive applications: Synthesis and structural characterisation

Materials Chemistry and Physics, 2011
A series of phosphosilicates P(2)O(5) (45 mol-CaO (20-40 mol-Na(2)O (5-20 mol-SiO(2) (10-15 mol has been synthesised by the sol-gel route using PO(OH)(3-x)(OC(2)H(5))(x) (x = 1, 2) as the phosphorus precursor. Evolution of the gels with temperature was studied using thermogravimetric analysis and differential thermal analysis.
CARTA, DANIELA, Newport RJ, Knowles JC, Smith ME, Guerry P.   +4 more
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Synthesis, Structural and Optical Properties of Bismuth‐Doped Sol‐Gel‐Derived Phosphosilicate Glasses

physica status solidi (a), 2018
Bismuth‐doped glasses are attractive materials for the development of new optical amplifiers and tunable laser sources. In this paper, Bi‐doped phosphosilicate glasses are prepared using the sol‐doping technique in combination with shaping using cold isostatic pressing.
El Hamzaoui, Hicham, Kinowski, Christophe, Razdobreev, Igor, Cassez, Andy, Bouwmans, Géraud, Prochet, Benoit, Capoen, Bruno, Bouazaoui, Mohamed   +7 more
openaire   +1 more source

Effect of precursors on the structure of phosphosilicate gels: 29Si and 31P MAS-NMR study

Journal of Non-Crystalline Solids, 1992
Gels were prepared using phosphoric acid, triethyl phosphate and trimethyl phosphite as the precursors of phosphorus. The upper limit for P 2 O 5 for gel formation is 90 mol% for gels using phosphoric acid and trimethyl phosphite, and 70 mol% for gels using triethyl phosphate.
S.-P. Szu, L.C. Klein, M. Greenblatt
openaire   +1 more source

Preparation and properties of europium-doped phosphosilicate glasses obtained by the sol–gel method

Journal of Non-Crystalline Solids, 2008
Abstract In this work, we report the synthesis of europium-doped phosphosilicate glasses from tetraethylorthosilicate (TEOS), phenyltrietoxysilane (PTES) and ammonium phosphate (NH4H2PO4) prepared by the sol–gel process. The matrix was synthesized by modified Stober methodology.
Lilian R. Avila, Evelisy C. de O. Nassor, Paula F.S. Pereira, Alexandre Cestari, Katia J. Ciuffi, Paulo S. Calefi, Eduardo J. Nassar   +6 more
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Preparation of Proton Conductive Phosphosilicate Gels Derived from 2-(Diethoxyphosphoryl)ethyltriethoxysilane

Chemistry Letters, 2000
Abstract The phosphosilicate gels derived from the mixture of 2-(diethoxyphosphoryl)ethyltriethoxysilane (DPTS) and tetraethoxysilane (TEOS) showed a high proton conductivity after a heat treatment at 450 °C. The high conductivity was brought by the generation of large amounts of isolated orthophosphoric acid in the gels due to the ...
Takao Kanzaki, Atsunori Matsuda, Yoshinori Kotani, Masahiro Tatsumisago, Tsutomu Minami   +4 more
openaire   +1 more source

Multinuclear NMR study of phosphosilicate gels derived from POCl3 and Si(OC2H5)4

Journal of Non-Crystalline Solids, 2005
Solid state H-1, Si-29 and (31)p MAS NMR have been used to investigate the microstructure of phosphosilicate gels prepared by a modified sol-gel method involving hydrolysis of silicon precursors in a solely aqueous environment at 50degreesC. Gels with molar compositions 5, 10, 20 and 30 mol% P2O5 in P2O5-SiO2 were studied.
N. J. CLAYDEN, PERNICE, PASQUALE, ARONNE, ANTONIO   +2 more
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Characterization of spin-coated silicate and phosphosilicate thin films prepared by the sol-gel method

Thin Solid Films, 1994
Abstract Spin-on glass (SOG) solutions for silicate and phosphosilicate films, respectively, were prepared by the sol-gel reaction of tetraethoxysilane (TEOS) in organic solvent. Fourier transform infrared (FTIR) and temperature-pro-grammed desorption (TPD) measurements were performed to investigate the bond configuration and thermal annealing ...
Chul Woo Nam, Seong Ihl Woo
openaire   +1 more source

Operation of PEFC using composite sheets composed of phosphosilicate gels and thermally stable organic polymers

Solid State Ionics, 2006
Abstract Thermally stable, flexible, and proton conductive composite sheets have been prepared from phosphosilicate (P 2 O 5 –SiO 2 , P/Si = 1 in mole ratio) gel powder and several kinds of organic polymers. The organic polymers examined were polyimide (PI), polyamideimide (PAI), polyvinylidene fluoride (PVdF) and styrene–ethylene–butylenes–styrene ...
Atsunori Matsuda, Naoki Nakamoto, Kiyoharu Tadanaga, Tsutomu Minami, Masahiro Tatsumisago   +4 more
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Proton conductivity at medium temperature range and chemical durability of phosphosilicate gels added with a third component

Solid State Ionics, 2003
Abstract Phosphosilicate (P 2 O 5 –SiO 2 ) gels with an addition of Al 2 O 3 or B 2 O 3 as a third component have been prepared by the sol–gel method aiming at the improvement in chemical durability of the gels. The presence of strongly interacted water with gel matrices was confirmed for all the gels from an endothermic peak with weight loss at ...
Atsunori Matsuda, Yoshitaka Nono, Kiyoharu Tadanaga, Tsutomu Minami, Masahiro Tatsumisago   +4 more
openaire   +1 more source