Design and Development of High Performance Proton Conducting Polymer Electrolyte Membranes for Fuel Cells

Abstract

Clean energy technology is crucial to addressing the rapid depletion of fossil fuels due to an increasing population and ecological harm. Fuel cell is considered as one the promising alternative sustainable energy conversion devices for the future energy requirements. The polymer electrolyte membrane fuel cell PEMFCs are the most desirable power sources because of their high efficiency, simple system features, and wide applications in transportation, aerospace, and mobile power stations. Proton exchange membrane is a key material in PEMFC, because it is not only provide ionic pathways to proton transfer, but also acts as a barrier between two electrodes. The most predominantly used PEM is commercially available perfluorinated membrane knows as Nafion® which is produced by DuPont in 1970. It possesses various advantages such as high proton conductivity along with good thermal and mechanical properties. Although it exhibits positive results, it causes some drawbacks such as (i) high expensive, (ii) difficult to synthesis, (iii) high fuel crossover, (iv) low glass transition temperature (Tg), (v) reduced proton conductivity at higher temperature, and so on, limited their use in PEMFCs. This made the researchers to develop alternative PEM materials based on organic inorganic composite membranes using various non-fluorinated aromatic hydrocarbons polymers with good proton conductivity, This thesis work demonstrates, an eco-friendly, cost effective polymer composite membrane based on poly vinyl alcohol, sulfonated polystyrene-block-poly(ethylene-ran-butylene) block polystyrene, and sulfonated poly ether ether sulfone. The effects of additives on pristine polymers (PVA, sPSEBPS, SPEES) were thoroughly discussed newline