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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Proton and cesium conductivity in perfluorosulfonate ionomers at low and high relative humidity

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Autor(es):
Matos, Bruno R. ; da Silva, Jaqueline S. ; Santiago, Elisabete I. ; Parra, Duclerc F. ; Carastan, Danilo J. ; de Florio, Daniel Z. ; Andrada, Heber E. ; Carreras, Alejo C. ; Fonseca, Fabio C.
Número total de Autores: 9
Tipo de documento: Artigo Científico
Fonte: Solid State Ionics; v. 301, p. 86-94, MAR 2017.
Citações Web of Science: 1
Resumo

Nafion exhibits one of the highest proton conductivity at room temperature and it is the standard electrolyte of proton exchange membrane fuel cells (PEMFC). However, the temperature dependence of ionic conductivity of Nation is highly dependent on the measuring conditions and it is still a matter of debate. In the present study, detailed dielectric spectroscopy (DS) measurements in both dry (under N-2 flow) and water-saturated conditions were carried out in a broad range of temperature and frequency. Such DS results were correlated to differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) data taken in similar conditions. The main results revealed that in samples conditioned in N-2 flow (RH similar to 0%) the transport of both proton and cesium ions is coordinated with the dynamics of Nafion relaxations. In hydrated Nafion (proton form), conductivity measurements at different frequencies revealed two regimes: one at high-frequency, in which the Vogel-TammanFulcher (VTF) law indicates a close relation between the polymer glass transition temperature T-g; and, a second one at low frequency, bearing great similarity to the transport observed in nearly dry samples. The reported experimental results contribute to disentangle the intricate transport properties of Nafion. (C) 2017 Elsevier B.V. All rights reserved. (AU)

Processo FAPESP: 14/50279-4 - Brasil Research Centre for Gas Innovation
Beneficiário:Julio Romano Meneghini
Linha de fomento: Auxílio à Pesquisa - Programa Centros de Pesquisa em Engenharia
Processo FAPESP: 14/09087-4 - Estudos sobre o uso do bioetanol em células a combustível do tipo PEMFC e SOFC
Beneficiário:Marcelo Linardi
Linha de fomento: Auxílio à Pesquisa - Temático
Processo FAPESP: 13/50151-5 - Desenvolvimento de eletrólitos compósitos contendo partículas inorgânicas de alta condutividade protônica para células a combustível a etanol direto
Beneficiário:Bruno Ribeiro de Matos
Linha de fomento: Bolsas no Brasil - Pós-Doutorado