Results 241 to 250 of about 21,338 (294)
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Anhydrous Proton-Conducting Polymers
Annual Review of Materials Research, 2003▪ Abstract Anhydrous proton-conducting polymers usually consist of a more or less inert polymer matrix that is swollen with an appropriate proton solvent (in most cases, phosphoric acid). An outline of the different materials is provided, with a focus on PBI/H3PO4 blends that are currently most suitable for fuel cell applications.
Schuster, M., Meyer, W.
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Proton-Conducting Glass Electrolyte
Analytical Chemistry, 2007A new porous glass electrolyte consisting of heteropolyacids, i.e., phosphotungstic acid (PWA) and phosphomolybdic acid, was investigated and was found to yield a remarkably high proton conductivity of 1.014 S cm(-1) at 30 degrees C and 85% relative humidity.
Thanganathan, Uma, Masayuki, Nogami
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Proton conductance of cell membranes
Journal of Theoretical Biology, 1973Abstract Several workers have suggested that cell membranes have a high proton conductance. Our interest in this concept arose from the possibility that the nutrient (submucosal-facing) membrane of the gastric mucosa may have a high proton or hydroxyl ion conductance which would play a role in the regulation of the acid-base balance of the cell.
W S, Rehm +5 more
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Proton diffusion in proton conducting oxides
Phase Transitions, 1996Abstract Quasielastic neutron scattering was used to study the atomistic proton diffusion mechanism in Yb-doped SrCeO3, a proton conducting perovskite, simultaneously in space and time. Proton diffusion consists of a sequence of trapping and free diffusion events.
R. Hempelmann, Ch. Karmonik
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Journal of Applied Physics, 1997
Fast proton conducting glasses have been obtained in Mg(PO3)2 glasses by implantation of protons at 120 keV to a fluence of 1×1018 cm−2. The dc conductivity and the activation energy of the conduction in the implanted glasses are 5×10−4 s cm−1 at room temperature and 0.18 eV, respectively.
H.Hosono +4 more
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Fast proton conducting glasses have been obtained in Mg(PO3)2 glasses by implantation of protons at 120 keV to a fluence of 1×1018 cm−2. The dc conductivity and the activation energy of the conduction in the implanted glasses are 5×10−4 s cm−1 at room temperature and 0.18 eV, respectively.
H.Hosono +4 more
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Annual Review of Materials Research, 2003
▪ Abstract The structural and chemical parameters determining the formation and mobility of protonic defects in oxides are discussed, and the paramount role of high-molar volume, coordination numbers, and symmetry are emphasized. Symmetry also relates to the structural and chemical matching of the acceptor dopant.
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▪ Abstract The structural and chemical parameters determining the formation and mobility of protonic defects in oxides are discussed, and the paramount role of high-molar volume, coordination numbers, and symmetry are emphasized. Symmetry also relates to the structural and chemical matching of the acceptor dopant.
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Composite Proton‐Conducting Membranes for PEMFCs
Fuel Cells, 2007AbstractComposite membranes are of interest for PEMFCs and DMFCs. This paper describes a basic study of the influence of silica on the proton conductivity: (i) added as a filler to poly(vinylidene fluoride‐hexafluoropropylene) and poly(benzimidazole)‐based membranes activated with H3PO4, or (ii) included in the matrix of class II hybrids based on ...
Mustarelli, P +6 more
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Protonic and Electronic Conduction in Proton Conductive Solid Oxide Fuel Cells
MRS Proceedings, 2011ABSTRACTProtons can fit into the perovskite structure because the O-O distance is approximately that of ice. However, to achieve charge balance, -2e charge must be added for every two protons added. If O2- vacancies are introduced, for instance by doping barium cerate with yttrium to obtain ${\it Ba}^{2 + } {\it Ce}_{1 - {\it x}}^{4 + } {\it Y}_{\it x}^
V. Hugo Schmidt, Chih-Long Tsai
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Proton conduction in some solids and the fuel cell with a proton conducting electrolyte
International Journal of Hydrogen Energy, 1979Abstract The electrical conductivities of some organic and inorganic solids, such as the simple organic acids, NH4H2PO4, KH2PO4, H3BO3, λ-AIOOH, amine-sulfates and amine-phosphates, have been measured. A relatively high proton conductivity of about 1 × 10−3 ohm−1 cm−1 at 87°C was found in hexamethylenetetramine phosphate.
T TAKAHASHI +4 more
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Materials Research Bulletin, 1982
Abstract Protonic conduction in zeolites is optimized. The approach is based on a vehicle-mechanism for the transport process. The parameters controlling protonic conduction are discussed. Fully hydrated “NH4-zeolite A” has a room temperature conductivity of 2×10 −3 Ω −1 cm −1 .
K.D. Kreuer, W. Weppner, A. Rabenau
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Abstract Protonic conduction in zeolites is optimized. The approach is based on a vehicle-mechanism for the transport process. The parameters controlling protonic conduction are discussed. Fully hydrated “NH4-zeolite A” has a room temperature conductivity of 2×10 −3 Ω −1 cm −1 .
K.D. Kreuer, W. Weppner, A. Rabenau
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