Composites membranes based on Nafion and PAMAM dendrimers for PEMFC applications

•PAMAM dendrimers are incorporated into Nafion matrix to prepare membranes.•The membranes are tested in a DMFC and compared with recast bare Nafion.•Tests in 2 M methanol/air revealed higher performance of the dendrimer membrane.•PAMAM polymers turned out an effective option to reduce the methanol crossover.

The aim of this work consists in to incorporate organic compounds as PAMAM (Poly-amidoamine) dendrimers into the polymeric Nafion matrix to prepare composite membranes as a possible alternative to reduce methanol crossover effect. Composite Nafion membranes were prepared using a 3 wt% of Generation-4 hydroxyl-terminated PAMAM (G4OH) dendrimers containing 64-terminal OH-functional groups. The influence of PAMAM-(G4OH) dendrimer on chemical–physical properties of the composite membrane was highlighted resulting in a reduction of the methanol permeability (1.05 × 10−6 cm2 s−1) if compared to a recast bare Nafion membrane (8.19 × 10−6 cm2 s−1), used as a reference. Good proton conductivity was also observed for PAMAM-(G4OH) composite membrane. The polarization curves carried out at 100 °C in the presence of 2 M methanol have revealed the higher performance of the PAMAM-(G4OH) membrane when compared to a recast Nafion membrane.