SPEEK based Hybrid Proton Conducting Membrane for Fuel Cell Applications

Abstract

Expansion in energy requirement due to population growth and exhaustion of non-renewable energy has led to
extensive research on renewable alternative energy sources. Fuel cells have the potential to provide alternative clean and
green energy. In this research a novel and low cost methods has been initiated for the preparation of hybrid proton exchange
membrane. PEEK polymers have been sulfonated using sulfuric acid and the degree of sulfonation of 67% is obtained using
1H-NMR spectroscopy. The sulfonation of SPEEK polymer is identified by the new absorption bands at 1082 and 1224 cm
-1
due to stretching vibrations of the sulfonic acid group by FTIR spectroscopy. The electrolyte samples were prepared by
solution casting technique using SPEEK and sulfonated TiO2. The composite membranes exhibited improved mechanical
strength and low water uptake. The hydrolytic stability of the membrane is studied by contact angle measurement. Addition of
nanosized particles into the polymer electrolytes is better in improving the conductivity as well as mechanical properties of
the membrane. The proton conductivity was enhanced by the introduction of hydrophilic inorganic particles into the SPEEK
membranes, which might be an effective approach to increase the working temperature of the membrane. The conductivity
value of the composite membrane is of the order of 10-1
Scm-1 at 70˚C, observed under conditions of 100% humidity
conditions. The prepared hybrid membranes offer great potential for use as proton exchange membrane in fuel cells.