Results 151 to 160 of about 1,068 (171)

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
openaire   +3 more sources

Proton conduction of in-situ formed Cs2H5(SO4)2(PO4) within phosphosilicate gel

Solid State Ionics, 2012
Abstract Thermal behavior and a mechanism of the proton conduction were investigated for a composite with an in-situ formed Cs2H5(SO4)2(PO4) and a phophosilicate gel. The raw material compositions investigated were 0.4CsHSO4 − xP2O5−(0.6 − x)SiO2 with x = 0.20, 0.25, and 0.30.
Shuichi Arakawa, Masaru Matsuzawa
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
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

Solid state 1H NMR study, humidity sensitivity and protonic conduction of gel derived phosphosilicate glasses

Journal of Materials Chemistry, 2002
1H Magic Angle Spinning (MAS) NMR and 1H T1 and T1ρ relaxation times measurements were used to investigate structural aspects of gel derived glasses of composition 10P2O5·90SiO2 (10P) and 30P2O5·70SiO2 (30P), with the aim of understanding the different humidity sensitive behaviour observed for films of the same composition.
N. J. CLAYDEN, S. ESPOSITO, P. PERNICE, ARONNE, ANTONIO   +3 more
openaire   +6 more sources

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
openaire   +1 more source

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

The Fine and Fractal Structure and Protonic Conductivity of Phosphosilicate-Diamond Sol-Gel Nanocomposites

2005
Composite xerogels based on a phosphosilicate matrix filled with nanodiamonds were synthesized by sol-gel processing. The crystalline and fractal characteristics of the initial nanopowders were obtained using wide-angle X-ray scattering (WAXS) and small-angle X-ray scattering (SAXS) techniques.
V.V. Shilov, Yu.P. Gomza, O.A. Shilova, V.I. Padalko, L.N. Efimova, S.D. Nesin   +5 more
openaire   +1 more source

Composite Membrane of Sulfonated Poly (phenylene oxide) Doped with Phosphosilicate Gels for Direct Methanol Fuel Cell

Polymer Bulletin, 2006
The newly developed composite membranes of sulfonated poly (phenylene oxide) (SPPO) doped with phosphosilicate gel were prepared for direct methanol fuel cell (DMFC). SPPO with higher ion exchange capacity (IEC) value (IEC=2.83 mequiv./g) was chosen as polymer matrix, and the phosphosilicate gel with P/Si equal to 1.5 was employed as dopant ...
Deping Lu, Wei Lu, Cuihua Li, Jianhong Liu, Rong Guan   +4 more
openaire   +1 more source

Preparation and characterization of sulfonated poly(phenylene oxide) proton exchange composite membrane doped with phosphosilicate gels

Polymers for Advanced Technologies, 2007
AbstractA new class of proton exchange composite membranes made by incorporating phosphosilicate gels into SPPO matrix was prepared and characterized. The thermal stability was evaluated by TGA and DSC, and the amorphous structure information was provided from XRD.
Wei Lu, Deping Lu, Jianhong Liu, Cuihua Li, Rong Guan   +4 more
openaire   +1 more source