Graphene‐Based Nafion Nanocomposite Membranes: Enhanced Proton Transport and Water Retention by Novel Organo‐functionalized Graphene Oxide Nanosheets

Abstract

Novel nanostructured organo-modified layered materials based on graphene oxide carrying various hydrophilic functional groups (-NH(2), -OH, -SO(3)H) are prepared and tested as nanofillers for the creation of innovative graphene-based Nafion nanocomposites. The hybrid membranes are characterized by a combination of analytical techniques, which show that highly homogeneous exfoliated nanocomposites are created. The pulsed field gradient NMR technique is used to measure the water self-diffusion coefficients. Remarkable behavior at temperatures up to 140 °C is observed for some composite membranes, thereby verifying the exceptional water retention property of these materials. Dynamic mechanical analysis shows that hybrid membranes are much stiffer and can withstand higher temperatures than pure Nafion.

Orderly sandwich-shaped graphene oxide/Nafion composite membranes for direct methanol fuel cells

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Graphene oxide derivatives with variable alkyl chain length and terminal functional groups as supports for stabilization of cytochrome c

“…Aqueous dispersions of GO were produced using a modified Staudenmaier's method from graphite powder [23]. GO was functionalized with aminopropanoic acid, aminovaleric acid, aminoundecanoic acid, ethylene diamine, diaminobutane and hexamethylenediamine for the addition of carboxyl and amino groups, as described in previous works [11,20,24].…”

Hybrid Nanomaterials of Magnetic Iron Nanoparticles and Graphene Oxide as Matrices for the Immobilization of β-Glucosidase: Synthesis, Characterization, and Biocatalytic Properties

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