The disclosure provides an ion exchange membrane with ion-conducting nanochannels formed by crosslinking chitosan molecular chains to form a unique threefold helical conformation and nanochannels that facilitate ion transport. The crosslinking promotes ion conductivity, suppresses swelling in water, inhibits fuel permeation, and enhances mechanical strength. The ion exchange membrane is stable in harsh alkaline environments. The ion exchange membrane can be used in a direct methanol fuel cell that displays an exceptional power density of 305 mW cm.sup.−2.

The disclosure provides an ion exchange membrane with ion-conducting nanochannels formed by crosslinking chitosan molecular chains to form a unique threefold helical conformation and nanochannels that facilitate ion transport. The crosslinking promotes ion conductivity, suppresses swelling in water, inhibits fuel permeation, and enhances mechanical strength. The ion exchange membrane is stable in harsh alkaline environments. The ion exchange membrane can be used in a direct methanol fuel cell that displays an exceptional power density of 305 mW cm.sup.−2.

A biocell having an electrochemical cell. The electrochemical cell includes an anode, a first cathode and a second cathode, and first and second porous separator membranes, wherein the first membrane is placed between a first contact surface of the anode and a first surface of the first cathode, and wherein the second membrane is placed between a second contact surface of the anode and a first surface of the second cathode.

A biocell having an electrochemical cell. The electrochemical cell includes an anode, a first cathode and a second cathode, and first and second porous separator membranes, wherein the first membrane is placed between a first contact surface of the anode and a first surface of the first cathode, and wherein the second membrane is placed between a second contact surface of the anode and a first surface of the second cathode.

The invention relates to polymers comprising sulfonated 2,6-diphenyl-1,4-phenylene oxide repeating units, to a method for their preparation, and to their use in a membrane electrode assembly, in a proton exchange membrane, in a fuel cell, in an electrolyser, in an electrolytic hydrogen compressor or in a flow battery. The invention further relates to a proton exchange membrane comprising said polymer and to a method for the preparation of a proton exchange membrane from said polymer. The invention also relates to the use of the polymers in ion exchange materials.

The invention relates to polymers comprising sulfonated 2,6-diphenyl-1,4-phenylene oxide repeating units, to a method for their preparation, and to their use in a membrane electrode assembly, in a proton exchange membrane, in a fuel cell, in an electrolyser, in an electrolytic hydrogen compressor or in a flow battery. The invention further relates to a proton exchange membrane comprising said polymer and to a method for the preparation of a proton exchange membrane from said polymer. The invention also relates to the use of the polymers in ion exchange materials.

A zipped ion-exchange membrane (Z-IEM) having at least one cation-exchange polyelectrolyte (CEP) crosslinked with at least one anion-exchange polyelectrolyte (AEP), wherein the CEP has a molar fraction of positive charges (x) so that: (i) when x=0.5, the Z-IEM is a completely neutralized ion-exchange membrane; (ii) when x>0.5, the Z-IEM is a cation-conducting ion-exchange membrane; (iii) when x<0.5, the Z-IEM is an anion-conducting ion-exchange membrane.

The above zipped ion-exchange membrane (Z-IEM): (i) is based on a polymeric matrix; (ii) is endowed with a high conductivity for ionic species such as either H.sub.3O.sup.+, OH.sup.− or halides such as F.sup.−, Cl.sup.−, Br.sup.−, and I.sup.−; and (iii) is able to block as much as possible the crossover of other ionic species, such as: cations such as V.sup.2+, V.sup.3+, VO.sup.2+, VO.sup.2+, Fe.sup.2+, Fe.sup.3+, Cr.sup.2+, Cr.sup.3+, Ce.sup.3+, Ce.sup.4+, Ti.sup.3+, Ti.sup.4+, Mn.sup.2+, Mn.sup.3+, Zn.sup.2+, Pb.sup.2+, Np.sup.3+, Np.sup.4+, NpO.sub.2.sup.2+, NpO.sub.2.sup.+, Li.sup.+, Na.sup.+, K.sup.+, Rb.sup.+, Cs.sup.+, Mg.sup.2+, Ca.sup.2+, Sr.sup.2+, Ba.sup.2+; and anions such as F.sup.−, BF.sub.4.sup.−, Cl.sup.−, ClO.sup.−, ClO.sub.2.sup.−, ClO.sub.3.sup.−, ClO.sub.4.sup.−, Br.sup.−, Br.sub.3.sup.−, I.sup.−, I.sub.3.sup.−.

A zipped ion-exchange membrane (Z-IEM) having at least one cation-exchange polyelectrolyte (CEP) crosslinked with at least one anion-exchange polyelectrolyte (AEP), wherein the CEP has a molar fraction of positive charges (x) so that: (i) when x=0.5, the Z-IEM is a completely neutralized ion-exchange membrane; (ii) when x>0.5, the Z-IEM is a cation-conducting ion-exchange membrane; (iii) when x<0.5, the Z-IEM is an anion-conducting ion-exchange membrane.

The above zipped ion-exchange membrane (Z-IEM): (i) is based on a polymeric matrix; (ii) is endowed with a high conductivity for ionic species such as either H.sub.3O.sup.+, OH.sup.− or halides such as F.sup.−, Cl.sup.−, Br.sup.−, and I.sup.−; and (iii) is able to block as much as possible the crossover of other ionic species, such as: cations such as V.sup.2+, V.sup.3+, VO.sup.2+, VO.sup.2+, Fe.sup.2+, Fe.sup.3+, Cr.sup.2+, Cr.sup.3+, Ce.sup.3+, Ce.sup.4+, Ti.sup.3+, Ti.sup.4+, Mn.sup.2+, Mn.sup.3+, Zn.sup.2+, Pb.sup.2+, Np.sup.3+, Np.sup.4+, NpO.sub.2.sup.2+, NpO.sub.2.sup.+, Li.sup.+, Na.sup.+, K.sup.+, Rb.sup.+, Cs.sup.+, Mg.sup.2+, Ca.sup.2+, Sr.sup.2+, Ba.sup.2+; and anions such as F.sup.−, BF.sub.4.sup.−, Cl.sup.−, ClO.sup.−, ClO.sub.2.sup.−, ClO.sub.3.sup.−, ClO.sub.4.sup.−, Br.sup.−, Br.sub.3.sup.−, I.sup.−, I.sub.3.sup.−.

The invention relates to:—anion exchange blend membranes consisting the following blend components:—a halomethylated polymer (a polymer with —(CH2)x—CH2—Hal groups, Hal=F, CI, Br, I; x=0-12), which is quaternised with a tertiary or a n-alkylated/n-arylated imidazole, an N-alkylated/N-arylated benzimidazole or an N-alkylated/N-arylated pyrazol to form an anion exchanger polymer. - an inert matrix polymer in which the anion exchange polymer is embedded and which is optionally covalently crosslinked with the halomethylated precursor of the anion exchanger polymer,—a polyethyleneglycol with epoxide or halomethyl terminal groups which are anchored by reacting with N—H-groups of the base matrix polymer using convalent cross-linking—optionally an acidic polymer which forms with the anion-exchanger polymer an ionic cross-linking (negative bound ions of the acidic polymer forming ionic cross-linking positions relative to the positive cations of the anion-exchanger polymer)—optionally a sulphonated polymer (polymer with sulphate groups —SO2Me, Me=any cation), which forms with the halomethyl groups of the halomethylated polymer convalent crosslinking bridges with sulfinate S-alkylation. The invention also relates to a method for producing said membranes, to the use of said membranes in electrochemical energy conversion processes (e.g. Redox-flow batteries and other flow batteries, PEM-electrolyses, membrane fuel cells), and in other membrane methods (e.g. electrodialysis, diffusion dialysis).

The invention relates to:—anion exchange blend membranes consisting the following blend components:—a halomethylated polymer (a polymer with —(CH2)x—CH2—Hal groups, Hal=F, CI, Br, I; x=0-12), which is quaternised with a tertiary or a n-alkylated/n-arylated imidazole, an N-alkylated/N-arylated benzimidazole or an N-alkylated/N-arylated pyrazol to form an anion exchanger polymer. - an inert matrix polymer in which the anion exchange polymer is embedded and which is optionally covalently crosslinked with the halomethylated precursor of the anion exchanger polymer,—a polyethyleneglycol with epoxide or halomethyl terminal groups which are anchored by reacting with N—H-groups of the base matrix polymer using convalent cross-linking—optionally an acidic polymer which forms with the anion-exchanger polymer an ionic cross-linking (negative bound ions of the acidic polymer forming ionic cross-linking positions relative to the positive cations of the anion-exchanger polymer)—optionally a sulphonated polymer (polymer with sulphate groups —SO2Me, Me=any cation), which forms with the halomethyl groups of the halomethylated polymer convalent crosslinking bridges with sulfinate S-alkylation. The invention also relates to a method for producing said membranes, to the use of said membranes in electrochemical energy conversion processes (e.g. Redox-flow batteries and other flow batteries, PEM-electrolyses, membrane fuel cells), and in other membrane methods (e.g. electrodialysis, diffusion dialysis).