Comparison Between the Conductivities of Protons Measured Experimentally with the Obtained by Molecular Dynamics Simulations in Sulfonated Polyphenyl Sulfones Membranes Articles uri icon

publication date

  • April 2008

start page

  • 87

end page

  • 94

issue

  • 2

volume

  • 11

International Standard Serial Number (ISSN)

  • 1480-2422

abstract

  • Full Molecular Dynamics was used to simulate separately the diffusion of naked protons and H₃O⁺ hydrated protons acrosssulfonated polyphenyl sulfones, (sPS). The diffusion coefficient of naked protons is nearly one order of magnitude higher than that of thehydrated protons for the membranes with the lower water uptake (10%). The conductivities simulated at 300 K for the hydrated protonacross membranes with water uptake 18% and 30 % are roughly similar to those both experimentally measured for the sPS4 membranewith ion exchange capacity = 1.8 eq/Kg in dry conditions and with water uptake = 24.3 %. The comparison between four sPS membranesshwon the strong dependence of conductivity with the water content into the membranes. In our study, the conductivity of sPS1 with a 3.1%water content decrease two order of magnitude respect the sPS4 with 24.3 of water content. Simulated conductivities of both naked protonsand hydrated protons follow Arrhenius behavior.

keywords

  • proton conductivity; molecular simulation; polysulfone; diffusion coefficient