Magnetically aligned nanodomains: application in high-performance ion conductive membranes.
Polyelectrolyte-coated magnetic nanoparticles were prepared by decorating the surface of superparamagnetic iron oxide nanoparticles (SPIONs) with crosslinked chitosan oligopolysaccharide (CS). These positively charged particles (CS-SPIONs) were then added to a negatively charged polymer (Nafion), and cast into membranes under an applied magnetic field. TEM and SAXS measurements confirmed this process created aligned, cylindrical nanodomains in the membranes. This was also indirectly confirmed by proton conductivity values. The strong electrostatic interaction between chitosan and Nafion prevented oxygen permeability and water evaporation at elevated temperatures through the proton conductive channels. The resultant proton exchange membranes showed lower conduction dependency to relative humidity, which is highly desirable for hydrogen fuel cells. The fuel cell performance tests were performed on the designed polyelectrolyte membrane by hydrogen-oxygen single cells at elevated temperature (120 °C) and low relative humidity.
School of Materials Science and Engineering and G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology , Atlanta, Georgia 30332-0245, United States.
Mohammad Mahdi
MM
Hasani-Sadrabadi
Fatemeh Sadat
FS
Majedi
Géraldine
G
Coullerez
Erfan
E
Dashtimoghadam
Jules John
JJ
VanDersarl
Arnaud
A
Bertsch
Homayoun
H
Moaddel
Karl I
KI
Jacob
Philippe
P
Renaud
D048271:Chitosan / Q000737:chemistry; D003911:Dextrans / Q000737:chemistry; D011211:Electric Power Supplies; D004566:Electrodes; D004573:Electrolytes / Q000737:chemistry; D005465:Fluorocarbon Polymers / Q000737:chemistry; D006813:Humidity; D006859:Hydrogen / Q000737:chemistry; D007477:Ions / Q000737:chemistry; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D008567:Membranes, Artificial; D010100:Oxygen / Q000737:chemistry; D011522:Protons; D055672:Static Electricity; D013696:Temperature
D003911:Dextrans; D004573:Electrolytes; D005465:Fluorocarbon Polymers; D007477:Ions; D058185:Magnetite Nanoparticles; D008567:Membranes, Artificial; D011522:Protons; C040402:perfluorosulfonic acid; D006859:Hydrogen; D048271:Chitosan; C065507:ferumoxides; D010100:Oxygen