Composite Polymer Electrolytes for Fuel Cell Applications: Filler‐Induced Effect on Water Sorption and Transport Properties

Abstract

Nafion- and sulfonated polysulfone (SPS)- based composite membranes were prepared by incorporation of SnO2 nanoparticles in a wide range of loading (0${ \div }$35 wt. %). The composites were investigated by differential scanning calorimetry, dynamic vapor sorption and electrochemical impedance spectroscopy to study the filler effect on water sorption, water mobility, and proton conductivity. A detrimental effect of the filler was observed on water mobility and proton conductivity of Nafion-based membranes. An increase in water mobility and proton conductivity was instead observed in SPS-based samples, particularly at low hydration degree. Analysis of the water sorption isotherms and states of water revealed that the presence of SnO2 in SPS enhances interconnectivity of hydrophilic domains, while not affecting the Nafion microstructure. These results enable the design of suitable electrolyte materials that operate in proton exchange membrane fuel cell conditions.

Preparation and evaluation of Nafion/SnO2 nanocomposite for improving the chemical durability of proton exchange membranes in fuel cells

“…This change is due to decrease of sulfonic acid groups in the composite membrane. 36 Membrane proton conductivity (s) is one of the crucial properties affecting PEM fuel cells performance. 37,38 In this regards, the proton conductivity of membranes was measured using AC impedance method at room temperature.…”