Nafion–TiO2 hybrid membranes for medium temperature polymer electrolyte fuel cells (PEFCs)

Nafion®–sepiolite composite membranes for improved proton exchange membrane fuel cell performance

“…Non-fluorinated polymers such as PEEK [4,5,6], PSU [7,8] or PBI [9,10,11,12] and their sulfonated counterparts have been extensively studied as alternatives. Another strategy consists in incorporating inorganic fillers such as metal oxides [13,14,15,16,17,18,19,20,21], acids [22,23,24,25,26], phosphates or phosphonates [27,28,29] into the Nafion® matrix to make the composite or hybrid membrane more mechanically stable, less permeable to reactant and more hygroscopic. Different clays, montmorillonite [30,31,32] or laponite [33] for instance, have also been evaluated as possible fillers.…”

On the proton conductivity of Nafion–Faujasite composite membranes for low temperature direct methanol fuel cells

“…Many types of inorganic fillers have been reported to decrease the methanol crossover of Nafion membrane. Although some improved electrochemical characteristics have been reported, especially when intrinsically proton conducing fillers have been used, most of the composite membranes have lower proton conductivity than the pure Nafion membrane [9][10][11][12][13][14][15][16][17][18][19].…”

Composite polymer electrolytes of sulfonated poly-ether-ether-ketone (SPEEK) with organically functionalized TiO2

“…Nanostructured TiO 2 , with a typical dimension less than 100 nm, is used in many applications ranging from UV shielding to solar cells and photocatalysts, owing to its peculiar properties. Its chemical stability, even under strongly acidic or basic conditions, and its capability to modify the hydrophilic/hydrophobic balance in the hybrid systems make the material suitable to be used as filler in polymeric electrolyte membranes [24,25]. The presence of the inorganic filler is expected to accentuate the phase separation between the hydrophobic and hydrophilic domains, which is a factor controlling the water channeling and proton conductivity in PEMFCs [26,27].…”