Polybenzimidazole-based block copolymers: From monomers to membrane electrode assemblies for high temperature polymer electrolyte membrane fuel cells

Sulfonated polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene based membranes containing CuO@g-C3N4 embedded with 2,4,6-triphenylpyrylium tetrafluoroborate for fuel cell applications

New series of polymer composite membranes were prepared from sulfonated polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene (S-PSEBS) and copper oxide loaded in graphitic carbon nitride (CuO@N-C) embedded with an ionic liquid, 2,4,6-triphenylpyrylium tetrafluoroborate. The structural and physicochemical properties of the composite membranes were studied in detail. Electrolyte membrane loaded with 8.0 wt% of CuO@N-C exhibited the maximum ion-exchange capacity of 3.1 meq. g^-1, whereas that of the pristine membrane was restricted to 1.8 meq. g^-1. From the TGA profile of the composite membrane, it was found to exhibit adequate thermal stability to be employed as electrolyte in fuel cells. Proton conductivity of the composite membranes was found to be in the range between 0.0179 S cm^-1 and 0.0229 S cm^-1. Indeed, the substantial results achieved with the S-PSEBS/CuO@N-C composite membranes were indicative of the notable features of the membranes for use in fuel cells.

Recent Progress in the Development of Composite Membranes Based on Polybenzimidazole for High Temperature Proton Exchange Membrane (PEM) Fuel Cell Applications

The rapid increasing of the population in combination with the emergence of new energy-consuming technologies has risen worldwide total energy consumption towards unprecedent values. Furthermore, fossil fuel reserves are running out very quickly and the polluting greenhouse gases emitted during their utilization need to be reduced. In this scenario, a few alternative energy sources have been proposed and, among these, proton exchange membrane (PEM) fuel cells are promising. Recently, polybenzimidazole-based polymers, featuring high chemical and thermal stability, in combination with fillers that can regulate the proton mobility, have attracted tremendous attention for their roles as PEMs in fuel cells. Recent advances in composite membranes based on polybenzimidazole (PBI) for high temperature PEM fuel cell applications are summarized and highlighted in this review. In addition, the challenges, future trends, and prospects of composite membranes based on PBI for solid electrolytes are also discussed.

Polybenzimidazole co-polymers: their synthesis, morphology and high temperature fuel cell membrane properties

Polybenzimidazole (PBI) random co-polymers containing alicyclic and aromatic backbones were synthesized using two different dicarboxylic acids (viz., cyclohexane dicarboxylic acid and terephthalic acid) by varying their molar ratios.

Formation and investigation of dual cross-linked high temperature proton exchange membranes based on vinylimidazolium-functionalized poly(2,6-dimethyl-1,4-phenylene oxide) and polystyrene

Dual-crosslinking provides a new strategy to enhance the dimensional and mechanical stabilities of membranes with high acid doping content and conductivity.