Decoration of carbon nanotube with SiO2 nanoparticles to improve polyelectrolyte membrane performance

To overcome the poor mechanical performance and the low proton conductivity at high temperature (> 80 degrees C) which hinder the utilization of Nafion membranes for use in PEM Fuel Cell, SiO2 nanoparticle decorated multi-walled carbon nanotubes (MWCNTs) were developed to reinforce both the mechanical property and the water retention capability of Nafion membranes. Results show that the composite membrane is approximately 10% and 5-10% higher than that of recast Nafion membrane in proton conductivity and water retention, respectively. These could be explained by the bifunction of SiO2 which performs both hydrophilicity and proton conductivity. In addition, the mechanical performance was greatly enhanced in the presence of SiO2 decorated MWCNTs.