Composite Nafion Membranes Containing Nanosize TiO2 ∕ SnO2 for Proton Exchange Membrane Fuel Cells

Abstract

Composite Nafion-based membranes containing nanosize and submicrometer-size titanium dioxide and tin dioxide were fabricated by recasting from Nafion solution. Proton exchange membrane fuel cell tests were conducted using these composite membranes at over a relative humidity (RH) range between 25 and 100%, using high-purity and gases. Cell tests were also conducted at and low RH. Composite membranes containing nano- and fillers showed a significant performance improvement over Nafion membranes without fillers and over composite membranes containing submicrometer-size and powders. The relative performance improvement was greater at higher temperature and low RH. The particle size (surface area) of the nanopowders plays an important role in water retention and performance of composite membranes at 80 and . The performance of composite membranes was slightly better than composite membranes for the same operating conditions.