Proton transfer and local structures in 3M (EW 825) and Nafion (EW 890) membranes are investigated in this study by both standard nonreactive molecular dynamics and the self-consistent iterative multistate empirical valence bond method, which is capable of simulating multiple reactive protons and accounting for the Grotthuss mechanism of proton transport. The Nafion and 3M systems have the same...

Cu-based gas diffusion electrodes (GDE) show excellent performance in the electrochemical reduction of CO2 to ethylene. In present work, we evaluate how solvent ink formulations containing Nafion-ionomer and unsupported Cu particles affects polymerized Nafion-copper distribution as-prepared GDE obtained CO2. Isopropanol (IPA), dimethyl sulfoxide (DMSO), ethylene glycol (EG), or N-methyl-2-pyrro...

Cathode catalysts and binders were examined for their effect on power densities in single chamber, air-cathode, microbial fuel cells (MFCs). Chronopotentiometry tests indicated thatthe cathode potential was only slightly reduced (20-40 mV) when Pt loadings were decreased from 2 to 0.1 mg cm(-2), and that Nafion performed better as a Pt binder than poly(tetrafluoroethylene) (PTFE). Replacing the...

Sulfonic acid-functionalized polymer electrolyte membranes alternative to Nafion(®) were developed. These were hydrocarbon systems, such as blend sulfonated polyetheretherketone (s-PEEK), new generation perfluorosulfonic acid (PFSA) systems, and composite zirconium phosphate-PFSA polymers. The membranes varied in terms of composition, equivalent weight, thickness, and filler and were investigat...

This study was motivated by the need for improved understanding of the kinetics and transport phenomena in a homogeneous catalyst system for the oxygen reduction reaction (ORR). Direct interaction between the sulfonic groups of Nafion and an Fe(III) meso-tetra(N-methyl-4-pyridyl) porphine chloride (Fe(III)TMPyP) compound was observed using FTIR and in situ UVeVis spectroelectrochemical characte...

Sulfonated polyelectrolyte membranes (PEMs), such as Nafion and styrene-olefin block copolymers, are explored as permselective membranes for fuel cells as well as suitable barrier materials against chemical agents. The permselective properties of PEM are determined by their microphase segregation into hydrophilic and hydrophobic domains. We performed classical molecular dynamics simulations of ...

The structure of Nafion, the polymer electrolyte membrane used in some fuel cells, has been extensively debated over recent decades. Now, a newly proposed model reveals the nanoscale arrangement that could explain the excellent transport properties of the material. Transport is a major source of pollution in cities. As a result, the development of cars and buses which generate low or negligible...

Ionic polymer-metal composites ~IPMCs! consist of a polyelectrolyte membrane ~usually, Nafion or Flemion! plated on both faces by a noble metal, and is neutralized with certain counter ions that balance the electrical charge of the anions covalently fixed to the backbone membrane. In the hydrated state ~or in the presence of other suitable solvents!, the composite is a soft actuator and sensor....

The proton conductivity of a series of extruded Nafion membranes @of equivalent weight ~EW! of 1100 and nominal dry thickness of 51, 89, 127, and 178 mm# has been studied. Measurements were made in 1 M H2SO4 at 298 K using a four-electrode, dc technique. The membrane area resistance increases with thickness, as expected, from 0.07 to 0.16 V cm for Nafion 112 and Nafion 117, respectively. Howeve...

A simple and cost effective solid-phase microextraction device has been developed. Fused-silica capillaries were etched with ammonium hydrogen difluoride prior to coating with an ionic liquid. For comparison, both a bare fused-silica capillary and one pretreated with a Nafion membrane were coated with the ionic liquid. All three coated capillaries were employed for the head space microextractio...