Počet záznamů: 1  

Changes in Nafion® 117 internal structure and related properties during exposure to elevated temperature and pressure in an aqueous environment

  1. 1.
    0486339 - UMCH-V 2019 RIV GB eng J - Článek v odborném periodiku
    Mališ, J. - Paidar, M. - Bystroň, T. - Brožová, Libuše - Zhigunov, Alexander - Bouzek, K.
    Changes in Nafion® 117 internal structure and related properties during exposure to elevated temperature and pressure in an aqueous environment.
    Electrochimica acta. Roč. 262, 1 February (2018), s. 264-275. ISSN 0013-4686
    Institucionální podpora: RVO:61389013
    Klíčová slova: Nafion * elevated temperature * excessive swelling
    Kód oboru RIV: CG - Elektrochemie
    Obor OECD: Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis)
    Impakt faktor: 5.383, rok: 2018

    In this study the behaviour and structure of a Nafion® 117 membrane exposed to liquid water at temperatures and pressures of up to 150 °C and 700 kPa, respectively, were investigated. The results clearly showed that, as the temperature of the environment approaches or exceeds the glass transition temperature of the membrane, it undergoes extensive swelling. This is connected with several changes in the membrane structure which have a predominantly detrimental influence on the functional properties of the membrane, such as ionic conductivity and ionic exchange capacity. The extent and rate of the changes increase with both rising temperature and pressure. While the changes at 150 °C and 700 kPa take place in the order of tens of minutes, at 110 °C and 500 kPa several hundreds of hours are required. The changes are enabled by amorphisation of pseudo-crystalline domains which are responsible for keeping the membrane structure intact. The changes in the internal structure were followed using small-angle X-ray scattering and visualised by current-sensing atomic force microscopy.
    Trvalý link: http://hdl.handle.net/11104/0282585