titolo

08/04/15 Seminario Dr. Plazanet

target

totem,dipartimento,ppim

inizio

Mercoledì 08 Aprile 2015 ore 15:00

luogo

Aula A, p.1 Sede di via Pascoli

relatore

Dr. Marie Plazanet (Dip. Fisica e Geologia, UniPG)

titoloevento

Nafion: from fuel cells applications to the physics of confined electrolytes

abstract

Nafion(R) is an amphiphilic polymer made of fluorated chains carrying hydrophilic sulfonate anions. It is widely used in various applications, for which the most famous is the use as proton conducting membranes in fuel cells. Its useful properties, related to the water structure and dynamics, are the result of a complex polymer organization in which the hydrophilic side chains are organized to form a percolating network of channels and cavities of nanometer size. These are filled with - unusually behaving - water upon hydration.
Below 0 degrees Celsius, water desorption and ice formation can be observed down to ~200 K. The phenomenon is reversible, so that water transport and ice melting can be observed at unusual temperatures.
Combining several experimental techniques, including non linear optical spectroscopy and neutrons diffraction, we could quantitatively explain the data in considering both entropic and confinement effects. The phenomenon may be general to most confined electrolytes, however rarely observed due to the restrictive conditions required.

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IX Seminario del Ciclo tematico della serie "La Ricerca nel Dipartimento Presentata dai Giovani Ricercatori - Anno Accademico 2014/2015" - Argomenti selezionati tra: Fisica Teorica, Fisica delle Particelle e Astrofisica, Fisica delle Micro e Nano Strutture, Geomateriali, Geotermia, Rischio Vulcanico e Ambientale, Geologia Applicata, Geofisica, Idrogeologia e Geomorfologia, Geologia del Sedimentario, Paleontologia, Geologia Strutturale e Geofisica.

people

Tutti gli interessati sono invitati a partecipare.

organizzatori

Prof. Lucio Cerrito (Dip. Fisica e Geologia, UniPG)

docsrefs

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