Enhancement of service life of polymer electrolyte fuel cells through application of nanodispersed ionomer

Abstract

In polymer electrolyte fuel cells (PEFCs), protons from the anode are transferred to the cathode through the ionomer membrane. By impregnating the ionomer into the electrodes, proton pathways are extended and high proton transfer efficiency can be achieved. Because the impregnated ionomer mechanically binds the catalysts within the electrode, the ionomer is also called a binder. To yield good electrochemical performance, the binder should be homogeneously dispersed in the electrode and maintain stable interfaces with other catalyst components and the membrane. However, conventional binder materials do not have good dispersion properties. In this study, a facile approach based on using a supercritical fluid is introduced to prepare a homogeneous nanoscale dispersion of the binder material in aqueous alcohol. The prepared binder exhibited high dispersion characteristics, crystallinity, and proton conductivity. High performance and durability were confirmed when the binder material was applied to a PEFC cathode electrode.

Highly Dispersed CeOx Hybrid Nanoparticles for Perfluorinated Sulfonic Acid Ionomer–Poly(tetrafluoethylene) Reinforced Membranes with Improved Service Life

“…For comparison, a PFSA–PTFE reinforced membrane without the use of any CeO x dispersions was also prepared and named as PFM. Finally, CeO x _A PFM and CeO x _B PFM were treated in 0.5 M H 2 SO 4 for 2 h and boiling deionized water for another 2 h (method II [ 22 , 30 , 31 , 32 , 33 , 34 ]). The acid treatment has been widely used to remove metallic cations existing in the membranes by exchanging the cations that participate in the ionic bonding with –SO 3 − groups in the PFSA matrices with protons, while the boiling water treatment was conducted to wash off excessive H 2 SO 4 molecules from the membranes.…”

Distinguishing Adsorbed and Deposited Ionomers in the Catalyst Layer of Polymer Electrolyte Fuel Cells Using Contrast-Variation Small-Angle Neutron Scattering

“… 3 , 4 Thus, the effect of the ionomer fraction has been investigated to control its structure, 5 , 6 and previous studies have reported improved PEFC performances with an increase in the ionomer distribution homogeneity. 7 , 8 …”

A Study to Enhance the Nitrate-Nitrogen Removal Rate without Dismantling the NF Module by Building a PFSA Ionomer-Coated NF Module

“…A perfluorosulfonic acid ionomer (PFSA ionomer) consists of a polytetrafluoroethylene (PTFE) backbone having a chemically strong structure [ 12 ] and a perfluoro side chain containing a sulfonic acid group (-SO 3 H) at the end [ 13 ]. The perfluoro structure containing sulfonic acid induces a hydrophobic/hydrophilic microphase separation form for fast proton conduction [ 14 ].…”