Electrode materials for membrane electrode assembly

A membrane electrode assembly (MEA), comprising:

• a support, and
• a catalyst/ionomer layer, said catalyst/ionomer layer comprising a first cross-linked ionomer and a catalyst, wherein the first cross-linked ionomer comprises:
• a plurality of first repeat units, wherein each first repeat unit is a moiety represented by a structural formula
• a plurality of second repeat units, wherein each second repeat unit is a moiety represented by a structural formula
• and a plurality of cross-linking moieties, wherein each cross-linking moiety is represented by structural formula (I) or (II):
• wherein, for each occurrence of the cross-linking moiety, the symbol represents a point of attachment to L2 and the symbol represents a point of attachment to a first repeat unit or a second repeat unit;
• and further wherein:
• is a moiety represented by the following structural formula:
• is a moiety represented by one of the following structural formulas:
• is a moiety represented by one of the following structural formulas:
• W is C1-12 alkyl or a moiety represented by one of the structural formulas selected from:
• wherein:
• the symbol represents a point of attachment to L3, and the symbol represents a double bond or a single bond;
• Z1, Z3, Z5, and Z7 each independently is a C1-3 alkylene or a bond;
• R1 is selected from H, a C1-12 alkyl, and C6-12 aryl, and
• Z4 is a bond or a C6-12 arylene, or
• Z4 is CH, and R1 and Z4 together with the C2 alkylene to which they are attached form a C5-12 cycloalkyl or a 5 to 12-membered heterocyclyl;
• and
• Z6 is selected from —CHR6—, a C5-12 cycloalkylene, and a 5 to 16-membered heterocyclylene;
• R3 is selected from H, a C1-12 alkyl, and C6-12 aryl, and
• Z8 is a bond or a C6-12 arylene, and CH, or
• Z8 is CH, and R3 and Z8 together with the C2 alkylene to which they are attached form a C5-12 cycloalkyl or a 5 to 12-membered heterocyclyl;
• and
• Z9 is NR10 or a bond;
• R5 and R6 each independently is H or a C1-12 alkyl;
• R7, R8, and R9 each independently is selected from NR11R12, a C6-12 aryl, and 5 to 12-membered heterocyclyl;
• R10 is a C1-12 alkyl;
• R11 and R12 each independently is C1-12 alkyl or a C3-12 cycloalkyl, or R11 and R12 together with the nitrogen atom to which they are attached form a 5 to 12-membered heterocyclyl;
• R13 is selected from a C1-12 alkyl, C6-12 aryl, and 5 to 12-membered heterocyclyl;
• R14 is a C1-12 alkyl or a C3-12 cycloalkyl;
• R15 and R16 each independently is selected from C1-12 alkyl, C6-12 aryl, and 5 to 12-membered heterocyclyl;
• or R15 and R16 together with the carbon atoms to which they are attached form a C6-12 aryl or a 5 to 12-membered heterocyclyl;
• and
• R17, R18, and R19 each independently is a C1-12 alkyl or a C3-12 cycloalkyl;
• or
• R18 and R19 together with the nitrogen atom to which they are attached form a 5 to 12-membered heterocyclyl and (i) R17 is a C1-12 alkyl or a C3-12 cycloalkyl, or (ii) R17 and at least one atom of L3 together with the nitrogen atom to which L3 and R17 are attached form a 5- to 12-membered heterocyclyl;
• or
• R17, R18, and R19 together with the nitrogen atom to which they are attached form a bicyclic 5 to 12-membered heterocyclyl;
• and
• Rx is selected from H, F, Cl, Br, OH, NH2, NO2, CN, C1-12 alkyl, C6-12 aryl, and 5 to 12-membered heterocyclyl, and 5 to 12-membered heteroaryl;
• L2 is selected from a C1-12 alkylene, C6-12 arylene, C6-12 arylene-C1-12 alkylene, C1-12 alkylene-C6-12 arylene, C1-12 alkylene-O—C1-12 alkylene, (O—C1-12 alkylene)m, (C1-12 alkylene-O)m, C(O)(O—C1-12 alkylene)m, OC(O)(C1-12 alkylene)m, C1-12 alkylene-NH—C1-12 alkylene, C1-12 alkylene-N(C1-12 alkyl)-C1-12 alkylene, C(O)(NH—C1-12 alkylene)m, (NH)C(O—C1-12 alkylene)m, (NH—C1-12 alkylene)m, and (C1-12 alkylene-NH)m;
• L3 is selected from a C1-12 alkylene, C6-12 arylene, C6-12 arylene-C1-12 alkylene, C1-12 alkylene-C6-12 arylene, C1-12 alkylene-O—C1-12 alkylene, (O—C1-12 alkylene)n, (C1-12 alkylene-O)n, C(O)(O—C1-12 alkylene)n, OC(O)(C1-12 alkylene)n, C1-12 alkylene-NH—C1-12 alkylene, C1-12 alkylene-N(C1-12 alkyl)-C1-12 alkylene, C(O)(NH—C1-12 alkylene)n, (NH)C(O—C1-12 alkylene)n, (NH—C1-12 alkylene)n, (C1-12 alkylene-NH)n, and a bond;
• m is an integer between 1 and 6;
• n is an integer between 1 and 6;
• Y2 is selected from —C(O)—, —O—, —S—, —NH—, —N(C1-12 alkyl)-, and a bond;
• X− is selected from F−, Cl−, Br−, OH−, NO−2, CN−, HCO3−, CO32−, PF6−, BF4−, and a C1-12 carboxylate;
• provided that W is C1-12 alkyl only when V is a cationic moiety,
• and wherein:
• each C1-12 alkylene, C6-12 arylene, C5-12 cycloalkylene, 5 to 16-membered heterocyclylene, C1-12alkyl, C3-12cycloalkyl, C5-12cycloalkyl, C6-12 aryl, and 5 to 12-membered heterocyclyl is independently optionally substituted with 1 to 6 substituents independently selected from the group consisting of F, Cl, Br, OH, NH2, NO2, oxo, CN, a C1-12 alkyl, C6-12 aryl, C1-12haloalkyl, C1-12 alkoxy, C6-12 aryl, C6-12 aryloxy, 5 to 12-membered heterocyclyl, 5 to 12-membered heteroaryl, NH(C1-12 alkyl), N(C1-12 alkyl)2, OC(O)(C1-12 alkyl), C(O)O(C1-12 alkyl), S(O)2(C1-12 alkyl), S(O)2(C6-12 aryl), NHC(O)(C1-12 alkyl), and C(O)NH(C1-12 alkyl).