What does Nafion 117 mean?
Nafion membranes are commonly categorized in terms of their EW and thickness. For example, Nafion 117 indicates an extrusion-cast membrane with 1100 g/mol EW and 0.007 inches (7 thou) in thickness.
What is Nafion binder?
Nafion binder is known to increase the electrochemically active surface area in the catalyst layer and the interfacial adhesion between the membrane and the electrode, thus decreasing cell resistance [17]. These factors bring enhanced performance in the fuel cells.
What is Nafion made from?
Nafion® made by DuPont is currently the standard membrane material for PEM fuel cells (Sethuraman, 2006) and PEM URFCs. Nafion comprises a polytetrafluoroethylene (PTFE) backbone with perfluorinated-vinyl-polyether side chains containing sulphonic acid end groups.
What is Nafion H?
Nafion-H® is a perflouroalkyl sulfonic acid resin. Its superacidity is due to the electron-withdrawing effect of the perflouroalkyl backbone to which the sulfonic acid group is attached (Olah et al., 1986).
Is Nafion hydrophobic?
Nafion consists of hydrophilic sulfonic acid groups dispersed in a hydrophobic matrix of tetrafluoroethylene and perfluoroalkyl ethers [18,24,44–53]. The sulfonic acid groups sorb water swelling the hydrophilic network through which water and protons are transported.
Is Nafion expensive?
The current state-of-the-art membrane, NAFION is too expensive, lacks selectivity, permitting leakage between anode and cathode electrolyte compartments.
Is Nafion membrane porous?
In practically all applications Nafion membranes are used as dense, non-porous flat sheet membranes with smooth surfaces.
What is Nafion tubing?
Nafion tubing is a highly selective, semi-permeable membrane to water vapor. If gases inside Nafion tubing are wetter than gases surrounding the tubing, drying will occur. If the surrounding gases are wetter, humidification will occur.
Is Nafion soluble in water?
No differences were found at 20 and 32°C, the two temperatures important to the present study. The solubilities in Nafion™ 117 are as follows: water, 22.0 g/g; methanol, 49.2 g/g; ethanol 45.0 g/g; propanol 48.6 g/g.
Is Nafion toxic?
The perfluorinated sulfonic acid copolymers used in Nafion™ membranes exhibit very low acute toxicity when administered in oral doses to rats. The LD50s are greater than 20,000 mg/kg of body weight.
Does Nafion dissolve in water?
Is Nafion hydrophilic or hydrophobic?
How does nafion-fe2+ work?
For the exchange technique (such as used in this study), Fe 2+ ions are allowed to penetrate into the Nafion membrane to form Nafion-Fe 2+. Once H 2 O 2 reagent is introduced, the reactive radicals (OH, OOH) are formed in the proximity to the Nafion matrix, which readily facilitates chemical decomposition (more detailed discussion in section 3.3).
Does H2O2 degrade Nafion membranes?
Thus, it would appear that the extent of the degradation of the Nafion membranes by H 2 O 2 was probably governed by the availability of Fe with a lower oxidation state [46], [49]. Fig. 1. Fractions of ion-exchange capacity (IEC), weight, and fluorine lost from M90 membranes as a result of H2 O 2 treatment.
What is the nomenclature of Nafion?
Nomenclature and molecular weight. Nafion can be produced as both a powder resin and a copolymer. It has various chemical configurations and thus several chemical names in the IUPAC system. Nafion-H, for example, includes the following systematic names:
What is the name of the compound H2O2?
Hydrogen peroxide. Hydrogen peroxide is a chemical compound with the formula H 2O 2. In its pure form, it is a pale blue, clear liquid, slightly more viscous than water. Hydrogen peroxide is the simplest peroxide (a compound with an oxygen–oxygen single bond ). It is used as an oxidizer, bleaching agent and antiseptic.