Disclosed herein are proton transport membranes and methods of making and use thereof. The proton transport membranes comprise: a two-dimensional (2D) material having a top surface and a bottom surface; wherein the two-dimensional material comprises graphene and hexagonal-boron nitride in an atomic ratio of from 100:0 to 0:100. In some examples: the top surface is functionalized with a first functional moiety and the bottom surface is not functionalized; the top surface is functionalized with a first functional moiety and the bottom surface is functionalized with the first functional moiety; or the top surface is functionalized with a first functional moiety and the bottom surface is functionalized with a second functional moiety, the second functional moiety being different than the first functional moiety. In some examples, the two-dimensional material is doped with a substitutional dopant in an amount of from greater than 0 atomic % (at %) to less than 100 at %.

Disclosed herein are supramolecular compositions, polyelectrolyte polymers, and polyelectrolyte crystals for proton conductivity prepared from organic ions, the organic ion comprising a molecular hub and arms extending therefrom, wherein the arms comprise a polymerizable moiety. Also disclosed herein are method of making and using the compositions, polymers, and crystals described herein.

Disclosed herein are supramolecular compositions, polyelectrolyte polymers, and polyelectrolyte crystals for proton conductivity prepared from organic ions, the organic ion comprising a molecular hub and arms extending therefrom, wherein the arms comprise a polymerizable moiety. Also disclosed herein are method of making and using the compositions, polymers, and crystals described herein.

Disclosed are redox flow battery membranes, redox flow batteries incorporating the membranes, and methods of forming the membranes. The membranes include a densified polybenzimidazole gel membrane that is capable of incorporating a high liquid content without loss of structure that is formed according to a process that includes in situ hydrolysis of a polyphosphoric acid solvent followed by densification of the gel membrane. The densified membranes are then imbibed with a redox flow battery supporting electrolyte such as sulfuric acid and can operate at very high ionic conductivities of about 50 mS/cm or greater and with low permeability of redox couple ions, e.g. vanadium ions, of about 10.sup.−7 cm.sup.2/s or less. Redox flow batteries incorporating the membranes can operate at current densities of about 50 mA/cm.sup.2 or greater.

A zinc iodine flow battery includes a positive end plate, a positive current collector, a negative current collector, a positive electrode with a flow frame, a membrane, a negative electrode with a flow frame, a negative end plate. The negative electrolyte is circulated between the negative storage tank and the negative cavity by pump. The negative pipe is provided with a branch pipe for the positive electrolyte circulation. The porous membrane between the positive and negative electrodes can realize the conduction of supporting electrolyte and prevent the diffusion of I3− to the negative electrolyte. In a duel-flow battery system, same electrolyte serves as both the positive electrolyte and the negative electrolyte, which is a mixed aqueous solution containing iodized and zinc salt. The membrane is porous membrane does not contain ion exchange group. Both the positive and negative electrolyte are neutral solutions.

A cationic copolymer comprises the divalent monomer units: wherein: each Ar.sup.1 independently represents phenylene; each L independently represents a direct bond or wherein each R.sup.1 independently represents an alkyl group having 1 to 4 carbon atoms, and each R.sup.2 independently represents an alkylene group having from 1 to 6 carbon atoms, and each Z.sup.− represents a non-interfering anion; each Ar.sup.2 independently represents an optionally substituted divalent aryl ring, with the proviso that if L represents a direct bond, then Ar.sup.2 represents an optionally substituted cationic divalent aryl ring accompanied by Z; each R.sup.3 independently represents H or an alkyl group having 1 to 6 carbon atoms; and each D independently represents a direct bond or Ar.sup.2, wherein adjacent D and L are not both direct bonds, and wherein if L is a direct bond, then D is Ar.sup.2. The cationic copolymer can be free-radially cured and used in a membrane.

A cationic copolymer comprises the divalent monomer units: wherein: each Ar.sup.1 independently represents phenylene; each L independently represents a direct bond or wherein each R.sup.1 independently represents an alkyl group having 1 to 4 carbon atoms, and each R.sup.2 independently represents an alkylene group having from 1 to 6 carbon atoms, and each Z.sup.− represents a non-interfering anion; each Ar.sup.2 independently represents an optionally substituted divalent aryl ring, with the proviso that if L represents a direct bond, then Ar.sup.2 represents an optionally substituted cationic divalent aryl ring accompanied by Z; each R.sup.3 independently represents H or an alkyl group having 1 to 6 carbon atoms; and each D independently represents a direct bond or Ar.sup.2, wherein adjacent D and L are not both direct bonds, and wherein if L is a direct bond, then D is Ar.sup.2. The cationic copolymer can be free-radially cured and used in a membrane.

A proton-conducting polymer comprises a plurality of repeating units of formula (I) for electrochemical reactions. The polymer may be synthesized from a super acid catalyzed polyhydroxyalkylation reaction of monomers Ar.sub.1′, Ar.sub.2′, and X.sub.1′ followed by a nucleophilic substitution reaction or a grafting reaction, and optionally an acidification reaction.

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Proton-exchange membranes and membrane electrode assemblies made from the polymer are also described.

Crosslinked membranes for anion exchange applications, and methods of making and using the same, are described.

Crosslinked membranes for anion exchange applications, and methods of making and using the same, are described.