Protic ionic liquids immobilized in phosphoric acid-doped polybenzimidazole matrix enable polymer electrolyte fuel cell operation at 200 °C

Protic ionic liquids (PILs) based on the anion bis(trifluoromethanesulfonyl)imide were confined in polybenzimidazole (PBI) matrices. Quasi-solidified ionic liquid membranes (QSILMs) were fabricated and examined for mechanical and thermal stability. After doping in phosphoric acid (PA), the QSILMs ex...

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Detalles Bibliográficos
Autores: Skorikova, Galina S., Rauber, Daniel, Aili, David, Martín Fernández, Santiago, Li, Qingfeng, Henkensmeier, Dirk, Hempelmann, Rolf
Tipo de recurso: artículo
Fecha de publicación:2020
País:España
Institución:Universidad Nacional de Educación a Distancia
Repositorio:e-spacio. Repositorio Institucional de la UNED
Idioma:inglés
OAI Identifier:oai:e-spacio.uned.es:20.500.14468/24354
Acceso en línea:https://hdl.handle.net/20.500.14468/24354
Access Level:acceso abierto
Palabra clave:12 Matemáticas::1299 Otras especialidades matemáticas
Polybenzimidazole
Protic ionic liquid
High temperature fuel cells
Immobilization
Polymer composite membrane
Descripción
Sumario:Protic ionic liquids (PILs) based on the anion bis(trifluoromethanesulfonyl)imide were confined in polybenzimidazole (PBI) matrices. Quasi-solidified ionic liquid membranes (QSILMs) were fabricated and examined for mechanical and thermal stability. After doping in phosphoric acid (PA), the QSILMs exhibited conductivities of 30–60 mS cm−1 at 180 °C. Fluorescence microscopy was used to investigate the structure of the composite PBI membranes. Membrane-electrode assemblies, fabricated with PA doped QSILMs, were tested in a single fuel cell and exhibited a performance increase with increasing temperature up to 200 °C. The best performance was obtained for the membrane electrode assembly containing 50 mol% of diethyl-methyl-ammonium bis(trifluoromethylsulfonyl)imide confined in the phosphoric acid doped PBI matrix with closed porosity. It reached 0.32 W cm−2 at 200 °C and 900 mA cm−2 . The catalyst layer of the gas diffusion electrode impregnated with protic ionic liquid exhibited better long-term stability than the gas diffusion electrode impregnated with phosphoric acid within 100 h of operation at 200 °C and anhydrous conditions.