New nanocomposite hybrid inorganic-organic proton-conducting membranes based on functionalized silica and PTFE.
Two types of new nanocomposite proton-exchange membranes, consisting of functionalized and pristine nanoparticles of silica and silicone rubber (SR) embedded in a polytetrafluoroethylene (PTFE) matrix, were prepared. The membrane precursor was obtained from a mechanical rolling process, and the SiO₂ nanoparticles were functionalized by soaking the membranes in a solution of 2-(4-chlorosulfonylphenyl)ethyl trichlorosilane (CSPhEtCS). The membranes exhibit a highly compact morphology and a lack of fibrous PTFE. At 125 °C, the membrane containing the functionalized nanoparticles has an elastic modulus (2.2 MPa) that is higher than that of pristine Nafion (1.28 MPa) and a conductivity of 3.6×10⁻³  S cm⁻¹ despite a low proton-exchange capacity (0.11 meq g⁻¹). The good thermal and mechanical stability and conductivity at T>100 °C make these membranes a promising low-cost material for application in proton-exchange membrane fuel cells operating at temperatures higher than 100 °C.
Department of Chemical Sciences, University of Padova, Italy. vito.dinoto@unipd.it
Vito
V
Di Noto
Matteo
M
Piga
Guinevere A
GA
Giffin
Enrico
E
Negro
Claudio
C
Furlan
Keti
K
Vezzù
D055595:Mechanical Phenomena; D008567:Membranes, Artificial; D053761:Nanocomposites / Q000737:chemistry*; D011138:Polytetrafluoroethylene / Q000737:chemistry*; D016062:Porosity; D011522:Protons; D012822:Silicon Dioxide / Q000737:chemistry*; D012826:Silicone Elastomers / Q000737:chemistry; D013696:Temperature; D014867:Water / Q000737:chemistry
D008567:Membranes, Artificial; D011522:Protons; D012826:Silicone Elastomers; D014867:Water; D012822:Silicon Dioxide; D011138:Polytetrafluoroethylene