Periodic Nafion-silica-heteropolyacids electrolyte t for PEM fuel cell operated near 200 °C

Periodic ordered Nafion-silica-heteropolyacids electrolyte is synthesized through a facile multiphase self-assembly between the positively charged silica, negatively charged HPW acids (H3PW12O40) and Nafion ionomers. The results exhibit uniform nanoarrays with long-range order of the electrolyte. The well-ordered proton conducting sites make the proton move through the membrane freely with low humidity dependence of proton transportation through the electrolyte. The Nafion-Silica-HPW electrolyte displays desirable conductivity at both low and elevated temperature. The proton conductivity of Nafion-Silica-HPW electrolyte at absolutely dry condition of 200 °C is 0.044 Scm−1. At low temperature of 75 °C, the proton conductivities of the electrolyte were 0.029 Scm−1 and 0.093 Scm−1 at absolute dry (0 RH%) and full humidifying condition (100 RH%), respectively.

► Multiphase self-assembly between silica
► HPW acids and Nafion ionomers
► Uniform nanoarray with long-range order
► Well-ordered proton conducting sites.