New modified Nafion-bisphosphonic acid composite membranes for enhanced proton conductivity and PEMFC performance

Proton exchange membranes remain a crucial material and key challenge to fuel cell science technology. In this work, new Nafion are prepared by casting method using aryl- or azaheteroaromatic bisphosphonate compounds as dopants. The incorporation of the dopant, considered at 1 wt% loading after previous selection, produces enhanced proton conductivity properties in membranes, different temperature relative humidity conditions, comparison with values obtained commercial Nafion. Water uptake ionic capacity (IEC) also assessed due their associated impact on transport properties, resulting superior than when tested same experimental conditions. These improvements doped prompted evaluation potential application cells, temperatures. membrane-electrode assemblies (MEAs), show an increased maximum power output until 60 °C 70 °C, followed decrease above these temperatures, Nafion-like behaviour measured membrane [1,4-phenylenebis(hydroxymethanetriyl)]tetrakis(phosphonic acid) (BP2) presents better results N-115 all studied performance ∼383 mW cm−2 °C. Open circuit potentials were always higher for MEAs indicating possibility advantageous restrain gas crossover membranes.