Effective Improvement of Water-Retention in Nanocomposite Membranes Using Novel Organo-Modified Clays as Fillers for High Temperature PEMFCs
Φόρτωση...
Ημερομηνία
Συγγραφείς
Nicotera, I.
Enotiadis, A.
Angjeli, K.
Coppola, L.
Ranieri, G. A.
Gournis, D.
Τίτλος Εφημερίδας
Περιοδικό ISSN
Τίτλος τόμου
Εκδότης
American Chemical Society
Περίληψη
Τύπος
Είδος δημοσίευσης σε συνέδριο
Είδος περιοδικού
peer reviewed
Είδος εκπαιδευτικού υλικού
Όνομα συνεδρίου
Όνομα περιοδικού
Journal of Physical Chemistry B
Όνομα βιβλίου
Σειρά βιβλίου
Έκδοση βιβλίου
Συμπληρωματικός/δευτερεύων τίτλος
Περιγραφή
Toward an enhanced water-retention of polymer electrolyte membranes at high temperatures, novel organo-modified clays were prepared and tested as fillers for the creation of hybrid Nafion nanocomposites. Two smectite clays (Laponite and montmorillonite), with different structural and physical parameters, were loaded with various cationic organic molecules bearing several hydrophilic functional groups (-NH(2), OH, -SO(3)H) and incorporated in Nafion by solution intercalation. The resulted hybrid membranes were characterized by a combination of powder X-ray diffraction, FTIR spectroscopy, and thermal analysis (DTA/TGA) showing that highly homogeneous exfoliated nanocomposites were created where the individual organoclay layers are uniformly dispersed in the continuous polymeric matrix. In this paper, water-transport properties were investigated by NMR spectroscopy, including pulsed-field-gradient spin-echo diffusion and spectral measurements conducted under variable temperature. Organo-montmorillonite nanofillers demonstrate a considerable effect on the Nafion polymer in terms both of water absorption/retention and water mobility with a remarkable behavior in the region of high temperatures (100-130 degrees C), denoting that the surface modifications of this clay with acid organic molecules significantly improve the performance of the final composite membrane. (1)H NMR spectral analysis allowed a general description of the water distribution in the system and an estimation of the number of water molecules involved in the hydration shell of the sulfonic groups as well as that absorbed on the organoclay particles.
Περιγραφή
Λέξεις-κλειδιά
layered silicate nanocomposites, fuel-cells, composite membranes, nafion membranes, smectite clays, nmr, operation, diffusion, transport, performance
Θεματική κατηγορία
Παραπομπή
Σύνδεσμος
<Go to ISI>://000292893300017
Γλώσσα
en
Εκδίδον τμήμα/τομέας
Όνομα επιβλέποντος
Εξεταστική επιτροπή
Γενική Περιγραφή / Σχόλια
Ίδρυμα και Σχολή/Τμήμα του υποβάλλοντος
Πανεπιστήμιο Ιωαννίνων. Σχολή Θετικών Επιστημών. Τμήμα Μηχανικών Επιστήμης Υλικών