Picture water droplets

Developing mathematical theories of the physical world: Open Access research on fluid dynamics from Strathclyde

Strathprints makes available Open Access scholarly outputs by Strathclyde's Department of Mathematics & Statistics, where continuum mechanics and industrial mathematics is a specialism. Such research seeks to understand fluid dynamics, among many other related areas such as liquid crystals and droplet evaporation.

The Department of Mathematics & Statistics also demonstrates expertise in population modelling & epidemiology, stochastic analysis, applied analysis and scientific computing. Access world leading mathematical and statistical Open Access research!

Explore all Strathclyde Open Access research...

Proton conductivity of Al(H2PO4)(3)-H3PO4 composites at intermediate temperature

Xu, Xiaoxiang and Tao, Shanwen and Irvine, John T. S. (2009) Proton conductivity of Al(H2PO4)(3)-H3PO4 composites at intermediate temperature. Solid State Ionics, 180 (4-5). pp. 343-350. ISSN 0167-2738

Full text not available in this repository. Request a copy from the Strathclyde author

Abstract

Composites of Al(H2PO4)(3) and H3PO4 were synthesised by soft chemical methods with different Al/P ratios. The Al(H2PO4)(3) obtained was found to have a hexagonal symmetry with parameter a = 13.687(3)angstrom, c = 9.1328(1)angstrom. The conductivity of this material was measured by a.c. impedance spectroscopy between 100 degrees C and 200 degrees C in different atmospheres. The conductivity of pure Al(H2PO4)(3) in air is in the order 10(-6)-10(-7) S/cm between 100 and 200 degrees C. For samples containing small excess of H3PO4, much higher conductivity was observed. The impedance responses of the composites were found to be similar with AlH2P3O10 center dot nH(2)O under different relative humidity. The conductivity of Al(H2PO4)(3)-H3PO4 composite with Al/P = 1/3.5 reached 6.6 mS/cm at 200 degrees C in wet 5% H-2. The extra acid is found to play a key role in enhancing the conductivity of Al(H2PO4)(3)-H3PO4 composite at the surface region of the Al(H2PO4)(3) in a core shell type behaviour. 0.7% excess of H3PO4 can increase the conductivity by three orders of magnitude. These composites might be alternative electrolytes for intermediate temperature fuel cells and other electrochemical devices. Conductivity (9.5 mS/cm) changed little, when the sample was held at 175 degrees C for over 100 h as the conductivity stabilised. (C) 2008 Elsevier B.V. All rights reserved.