Comparative study of composite membranes from nano‐metal‐oxide‐incorporated polymer electrolytes for direct methanol alkaline membrane fuel cells

A series of six composite membranes was prepared with two polymer electrolytes and three inorganic fillers, namely, silica, titania, and zirconia by a solution casting method. Two polymer electrolytes, that is, anion‐exchange membranes, were prepared from polystyrene‐block‐poly(ethylene‐ran‐butylene)‐block‐polystyrene (PSEBS) and polysulfone by chloromethylation and quaternization. A preliminary characterization of the ionic conductivity, methanol permeability, and selectivity ratio was done for all of the prepared composite membranes to check their suitability to work in direct methanol alkaline membrane fuel cells (DMAMFCs). The DMAMFC performance was analyzed with an in‐house fabricated single cell unit with a 25‐cm² area. Maximum performance was achieved for the composite membrane quaternized PSEBS/7.5% TiO₂ and was 74.5 mW/cm² at 60°C. For the comparison purposes, a commercially available anion‐exchange membrane (Anion Membrane International‐7001) was also investigated throughout the study. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013