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High Proton Conductivity (high + proton_conductivity)
Selected AbstractsHigh Proton Conductivity in Anodic ZrO2/WO3 Nanofilms,ANGEWANDTE CHEMIE, Issue 41 2009Damian Kowalski Dr. Der amorphe Doppeloxid-Nanofilm ZrO2/WO3, ein neuartiger protonenleitender Elektrolyt, kann leicht durch physikalische Dampfabscheidung (PVD) eines Zr/W-Films und anschließende anodische Oxidation erhalten werden (siehe Schema). Ein 60,nm dicker Oxidfilm verfügt bereits bei nur 100,°C über einen flächenspezifischen Widerstand von 0.2,,,cm2. [source] ChemInform Abstract: Compound of (NH4)2SnP4O13 with High Proton Conductivity in Both Dry and Humid Atmospheres as Electrolyte for Intermediate Temperature Fuel Cells.CHEMINFORM, Issue 1 2010Haibo Wang Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Polymer Electrolyte Membranes with a Pore-Filling Structure for a Direct Methanol Fuel Cell,ADVANCED MATERIALS, Issue 14 2003T. Yamaguchi Pore-filling membranes that are composed of a porous substrate and a filling polymer electrolyte have been developed. These polyelectrolyte membranes demonstrate low permeation with respect to methanol, high proton conductivity, good mechanical strength, chemical stability, and low cost, making them ideal for use in direct methanol fuel cells. The necessary characteristics can also be controlled by changing the substrate and the filling polymer electrolyte. [source] Sulfonated polybenzimidazoles: Proton conduction and acid,base crosslinkingJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 16 2010Owen D. Thomas Abstract A series of soluble, benzimidazole-based polymers containing sulfonic acid groups (SuPBI) has been synthesized. SuPBI membranes resist extensive swelling in water but are poor proton conductors. When blended with high ion exchange capacity (IEC) sulfonated poly(ether ether ketone) (SPEEK), a polymer that has high proton conductivity but poor mechanical integrity, ionic crosslinks form reducing the extent of swelling. The effect of sulfonation of PBI on crosslinking in these blends was gauged through comparison with nonsulfonated analogs. Sulfonic acid groups present in SuPBI compensate for acid groups involved in crosslinking, thereby increasing IEC and proton conductivity of the membrane. When water uptake and proton conductivity were compared to the IEC of blends containing either sulfonated or nonsulfonated PBI, no noticeable distinction between PBI types could be made. Comparisons were also made between these blends and pure SPEEK membranes of similar IEC. Blend membranes exhibit slightly lower maximum proton conductivity than pure SPEEK membranes (60 vs. 75 mS cm,1) but had significantly enhanced dimensional stability upon immersion in water, especially at elevated temperature (80 °C). Elevated temperature measurements in humid environments show increased proton conductivity of the SuPBI membranes when compared with SPEEK-only membranes of similar IEC (c.f. 55 for the blend vs. 42 mS cm,1 for SPEEK at 80 °C, 90% relative humidity). © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3640,3650, 2010 [source] Synthesis and properties of polyimides bearing acid groups on long pendant aliphatic chainsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 13 2006Tomohiro Yasuda Abstract A series of novel polyimide electrolytes having long pendant sulfo- or phosphoalkoxy groups were synthesized for fuel-cell applications. Sulfodecyloxy-, phosphodecyloxy-, and sulfophenoxydodecyloxy-substituted benzidine monomers were synthesized from dihydroxybenzidine. These monomers were copolymerized with naphthalene tetracarboxylic dianhydride and fluorenylidene dianiline to give the corresponding polyimides. A flexible, ductile, and self-standing membrane was obtained via casting from the polyimide solution. Because the acid groups were on long pendant side chains and away from the main chains, the polyimide membrane showed improved oxidative and hydrolytic stability in comparison with the polyimides with sulfonic acid groups on the main chains or on the short side chains. High thermal stability (no glass-transition temperature and a decomposition temperature > 200 °C) was also obtained. The polyimide membrane displayed high proton conductivity of 10,1 S cm,1 at 120 °C. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3995,4005, 2006 [source] Low Water Swelling and High Proton Conducting Sulfonated Poly(arylene ether) with Pendant Sulfoalkyl Groups for Proton Exchange MembranesMACROMOLECULAR RAPID COMMUNICATIONS, Issue 24 2007Jinhui Pang Abstract Novel side-chain-type sulfonated poly(arylene ether) with pendant sulfoalkyl group copolymers (PSA-SPAE-6F) have been synthesized by direct copolymerization from a new sulfonated monomer, sodium 3-(4-(2,6-difluorobenzoyl)phenyl)propane-1-sulfonate. The sulfonate content could be easily controlled by adjusting the sulfonated and the unsulfonated monomer feed ratio. The obtained copolymers all show good thermal and mechanical properties. It should be noted that the most highly sulfonated copolymer, PSA-SPAE-6F90 with an ion exchange capacity of 1.30 mequiv,·,g,1, shows a proton conductivity of 0.11 S,·,cm,1 and a water swelling ratio of only 12.9% at 100,°C, which indicates its high proton conductivity and excellent dimensional stability in hot water. [source] | |||||||||||||