초록 |
Modern electrochemical energy conversion devices require more advanced proton conductors for their broad applications. Phosphonated polymers have been proposed as anhydrous proton conductors for fuel cells. However, anhydride formation of phosphonic acid functional groups lowers proton conductivity and prevents its use in the fuel cell applications. Here, we report a poly(2,3,5,6-tetrafluorostyrene-4-phosphonic acid), which does not undergo anhydride formation, thus maintains protonic conductivity above 200°C. We used the phosphonated polymer in fuel cell electrodes with an ion-pair coordinated membrane in a membrane electrode assembly. The synergistically integrated fuel cell reached peak power densities of 1,130 mW cm-2 at 160°C and 1,740 mW cm-2 at 240°C under H2/O2 conditions, significantly outperforming polybenzimidazole- and metal phosphate-based fuel cells. |