Crown ether containing PEM electrode
View Patent ↗A membrane electrode assembly for fuel cells includes a proton conducting membrane having a first side and a second side. The membrane electrode assembly further includes an anode disposed over the first side of the proton conducting layer and a cathode catalyst layer disposed over the second side of the proton conducting layer. One or both of the anode catalyst layer and the cathode catalyst layer includes a first polymer which has cyclic polyether groups. An ink composition for forming a fuel cell catalyst layer is also provided.
1. A membrane electrode assembly for a fuel cell, the membrane electrode assembly comprising:
a proton conducting membrane having a first side and a second side;
an anode catalyst layer disposed over the first side of the proton conducting layer; and
a cathode catalyst layer disposed over the second side of the proton conducting layer, at least one of the anode layer or the cathode layer including a first polymer including cyclic polyether groups and platinum, the platinum being sequestered by the cyclic polyether groups, the membrane electrode positioned between a first gas diffusion layer and a second gas diffusion layer and between an anode flow field plate and a cathode flow field plate.
2. The membrane electrode assembly of claim 1 wherein the first polymer includes cyclic ether groups present in an amount from about 0.01 to about 5 weight percent of the total weight of the anode layer or the cathode layer.
3. The membrane electrode assembly of claim 1 wherein the cyclic polyether groups are cryptands or crown ethers.
4. The membrane electrode assembly of claim 1 wherein the first polymer including cyclic polyether groups is a linear polymer.
5. The membrane electrode assembly of claim 4 wherein the linear polymer has the following formula:
where R 1 is absent or a hydrocarbon group and CPG is a cyclic polyether group.
6. The membrane electrode assembly of claim 5 wherein R 1 is C 1-20 alkyl, C 1-18 polyether, C 6-20 alkylaryl, or C 6-20 aryl.
7. The membrane electrode assembly of claim 6 wherein CPG is selected from the group consisting of:
8. The membrane electrode assembly of claim 1 wherein the anode layer and the cathode catalyst layer each independently include a second polymer having sulfonic acid groups selected from the group consisting of perfluorosulfonic acid (PFSA) polymers, polymers having perfluorocyclobutyl moieties, and combinations thereof.
9. The membrane electrode assembly of claim 1 wherein the first polymer includes polystyrene crosslinked with divinylbenzene in the form of beads, fibers, particulates or nanoparticles are functionalized with metal ionophores, the metal ionophores including platinum sequestered by the cyclic polyether groups.
10. The membrane electrode assembly of claim 1 wherein the anode layer and the cathode catalyst layer each independently include a second polymer having perfluorocyclobutyl moieties.