Nafion titania nanotubes nanocomposite electrolytes for high-temperature direct methanol fuel cells

Nafion-based nanocomposite membranes containing various amounts of titania nanotubes (TNTs) as an inorganic filler have been prepared using melt-mixing method and have been investigated for proton exchange membrane applications. The one-dimensional TNTs have been prepared from potassium hydroxide using hydrothermal route and conventional heating. Nafion R1100 in a protonated form was used, and TNT contents were in a range of 0.52.0 wt. The acid-treated composite membranes, at lowest inorganic additive content, exhibited improved properties in terms of thermal stability and methanol (MeOH) permeability. The best performing nanocomposite was the membrane containing only 0.5 wt TNTs showing ionic conductivity value of 7.2 × 10 ^-2 S· cm ^-1 at 26°C and 100 of relative humidity.