Composite ion exchange membrane and method for producing same

Abstract

The present disclosure provides a composite ion exchange membrane and a method for making the same. The composite ion exchange membrane of the present disclosure includes a first layer including a first ion-conductive membrane, a second layer including a gas barrier membrane, and a third layer including a second ion-conductive membrane. A composite ion exchange membrane is provided herein. The composite ion exchange membrane of the present disclosure includes a first layer including a first ion-conductive membrane, a second layer including a gas barrier membrane, and a third layer including a second ion-conductive membrane. The second layer is disposed between the first layer and the third layer, such that a first side of the second layer is in physical contact with the first layer, and a second side of the second layer opposite the first side is in physical contact with the third layer.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Application No. 63 / 425,224, filed November 14, 2022, entitled "LAMINATED ION-CONDUCTING AND GAS-BLOCKING MEMBRANE LAYERS AND METHODS OF MAKING THE SAME," the entire contents of which are incorporated herein by reference.

[0002] Field of Disclosure FIELD OF THE DISCLOSURE The present disclosure relates to ion exchange membranes for use in electrolytic cells, and methods of making and using same. [Background technology]

[0003] background Electrolyzers use polymer-based ion-conducting membranes to separate ions, particularly hydrogen ions and hydroxy anions. Electrolyzer performance can be defined, in part, by the power density of the membrane, which refers to the amount of power per unit area that can be supported by the membrane at a given voltage. As power density increases, more surface area of ​​the ion-conducting membrane is required to support the same voltage at which a given yield of hydrogen can be reduced. Thinner ion-conducting membranes have lower resistance, thus allowing for increased power density. However, thinner membranes also increase hydrogen and oxygen permeation fluxes, resulting in less pure gas production streams. What is needed is an ion-conducting membrane with increased power density and reduced hydrogen and oxygen permeation fluxes. Summary of the Invention [Means for solving the problem]

[0004] Disclosure Overview A composite ion exchange membrane is provided herein. The composite ion exchange membrane of the present disclosure comprises a first layer comprising a first ion-conductive membrane, a second layer comprising a gas barrier membrane, and a third layer comprising a second ion-conductive membrane. The second layer is disposed between the first layer and the third layer, such that a first side of the second layer is in physical contact with the first layer, and a second side of the second layer opposite the first side is in physical contact with the third layer.

[0005] In some embodiments, the first ion-conducting membrane comprises a tetrafluoroethylene-based fluoropolymer-copolymer. Preferably, the tetrafluoroethylene-based fluoropolymer-copolymer has the formula CHF 13 O5S·C n F 2n where n is an integer between 3,000 and 10,000. In some embodiments, the third ion-conducting membrane comprises a tetrafluoroethylene-based fluoropolymer-copolymer. Preferably, the tetrafluoroethylene-based fluoropolymer-copolymer has the formula CHF 13 O5S·C n F 2n where n is an integer of 3,000 to 10,000.

[0006] In some embodiments, the gas barrier membrane comprises a sulfonated polymer. Preferably, the sulfonated polymer is sulfonated poly(ether ether ketone) (SPEEK), sulfonated phenylated poly(phenylene) (SPPP), sulfonated poly(ether sulfone) (SPES), sulfonated polystyrene-b-poly(ethylene-r-butylene)-b-polystyrene (S-SEBS), blends of sulfonated poly(ethylene oxide) blended with poly(vinyl alcohol), sulfonated polystyrene crosslinked with divinylbenzene, Selemion TM CMV, Neosepta TM CMS and Fumasep TM FKS30. In some embodiments, the gas barrier membrane comprises a plurality of channels, a plurality of pores, or a combination thereof.

[0007] In some embodiments, the first layer has a thickness of about 1 micron to about 50 microns. Preferably, the first layer has a thickness of about 5 microns to about 35 microns. In some embodiments, the second layer has a thickness of about 1 micron to about 50 microns. Preferably, the second layer has a thickness of about 5 microns to about 35 microns. In some embodiments, the third layer has a thickness of about 1 micron to about 50 microns. Preferably, the third layer has a thickness of about 5 microns to about 35 microns.

[0008] In some embodiments, the gas barrier membrane further comprises a catalyst. The catalyst is preferably in the form of nanoparticles. In some aspects, the catalyst comprises platinum, palladium, gold, iridium, osmium, rhodium, ruthenium, silver, or a combination thereof. In some additional aspects, the catalyst is embedded in the surface of the gas barrier membrane. In yet further aspects, the catalyst is dispersed throughout the gas barrier membrane.

[0009] In some embodiments, the gas barrier membrane comprises a scaffold. The scaffold comprises a supporting polymer. In some aspects, the supporting polymer comprises poly(ether ether ketone) (PEEK).

[0010] Further provided herein is a method of making a composite ion exchange membrane, which generally includes hot-pressing a first layer comprising a first ion-conducting membrane, a second layer comprising a gas barrier membrane, and a third layer comprising a second ion-conducting membrane to form the composite ion exchange membrane.

[0011] In some embodiments, hot welding is performed at a temperature of from about 100°C to about 300°C. Preferably, hot welding is performed at a temperature of from about 125°C to about 250°C.

[0012] In some embodiments, hot welding is performed at a pressure of about 100 psi to about 3000 psi. Preferably, hot welding is performed at a pressure of about 1000 psi to about 2000 psi.

[0013] In some embodiments, the hot welding is performed for about 1 minute to about 10 minutes. Preferably, the hot welding is performed for about 4 minutes to about 6 minutes.

[0014] In some embodiments, the method further comprises immersing the gas barrier membrane in a solution containing a catalyst prior to hot welding. The catalyst is preferably in the form of nanoparticles.

[0015] In some additional embodiments, the method further comprises spraying the gas barrier membrane with a solution comprising a catalyst. The catalyst is preferably in the form of nanoparticles. In some aspects, the spraying is performed using an air brush. In additional aspects, the spraying is performed by ultrasonic atomization. In some additional embodiments, the spraying produces a coating on the gas barrier membrane having a thickness of up to 0.5 microns.

[0016] In still further embodiments, the method further comprises spraying the first ion-conducting membrane and / or the second ion-conducting membrane with a solution containing a catalyst. The catalyst is preferably in the form of nanoparticles. In some aspects, the spraying is performed using an air brush. In additional aspects, the spraying is performed by ultrasonic spraying. In some additional embodiments, the spraying produces a coating on the first ion-conducting membrane and / or the second ion-conducting membrane having a thickness of at most 0.5 microns.

[0017] Further provided herein is a method for making a composite ion exchange membrane. The method generally includes the steps of casting a first layer solution (the first layer solution including a first ion-conductive membrane resin) on a substrate, drying the first layer solution to form a first layer, casting a second layer solution (the second layer solution including a gas barrier membrane resin) on the first layer, drying the second layer solution to form a second layer, casting a third layer solution (the third layer solution including a second ion-conductive membrane resin) on the second layer, and drying the third layer solution to form the third layer, thereby forming the composite ion exchange membrane.

[0018] Drying is carried out at a temperature of about 50° C. to about 100° C. Preferably, drying is carried out at a temperature of about 75° C. In some embodiments, drying is carried out overnight.

[0019] In some additional embodiments, the method further comprises spraying the gas barrier membrane with a solution comprising a catalyst. The catalyst is preferably in the form of nanoparticles. In some aspects, the spraying is performed using an air brush. In additional aspects, the spraying is performed by ultrasonic atomization. In some additional embodiments, the spraying produces a coating on the gas barrier membrane having a thickness of up to 0.5 microns.

[0020] In still further embodiments, the method further comprises spraying the first ion-conducting membrane and / or the second ion-conducting membrane with a solution containing a catalyst. The catalyst is preferably in the form of nanoparticles. In some aspects, the spraying is performed using an air brush. In additional aspects, the spraying is performed by ultrasonic spraying. In some additional embodiments, the spraying produces a coating on the first ion-conducting membrane and / or the second ion-conducting membrane having a thickness of at most 0.5 microns.

[0021] In some embodiments, the method may further include the step of adding a catalyst to the gas barrier membrane by immersing the gas barrier membrane in a solution containing a metal salt of the catalyst and reducing the metal salt of the catalyst in situ.

[0022] Further provided herein is a method for making a composite ion exchange membrane. Generally, the method includes the steps of providing a gas barrier membrane having a first side and a second side opposite the first side, forming pores or channels in the gas barrier membrane, and coating the first side of the gas barrier layer and the second side of the gas barrier layer with an ion-conducting membrane resin, thereby forming a composite ion exchange membrane.

[0023] In some embodiments, the step of forming pores or channels in the gas barrier membrane is performed using an optical laser.

[0024] In some embodiments, the step of forming pores or channels in the gas barrier membrane includes coating a pore-former composition on a first side of the gas barrier membrane and a second side of the gas barrier membrane, and removing the pore-former from the gas barrier membrane, thereby producing a porous gas barrier membrane. In some embodiments, the pore-former composition includes a gas barrier ion-conductive membrane resin and a pore-former. The pore-former can include polystyrene, a polystyrene derivative, polyethylene oxide, a polyethylene oxide derivative, polyvinylidene fluoride, a polyvinylidene fluoride derivative, carbon black, silica, polyacrylic acid, N-(2-hydroxypropyl)methacrylamide (HPMA), polyacrylamide (PAM), or a combination thereof. In some embodiments, the pore-former and the gas barrier ion-conductive membrane resin are present in the pore-former composition in a weight ratio of pore-former to gas barrier ion-conductive membrane resin of about 50:50 to about 90:10.

[0025] Further provided herein is a method for making a composite ion exchange membrane. Generally, the method includes the steps of: immersing a gas barrier ion-conductive membrane resin containing a first solvent in a non-solvent, so that the non-solvent replaces the first solvent in the gas barrier ion-conductive membrane resin; drying the gas barrier ion-conductive membrane resin to form a gas barrier membrane having a first side and a second side, the gas barrier membrane having a plurality of pores on the first side and a plurality of pores or channels on the second side; and coating the ion-conductive membrane resin on the first side of the gas barrier membrane and the second side of the gas barrier membrane, thereby forming a composite ion exchange membrane.

[0026] Further provided herein is an electrolyzer comprising the composite ion exchange membrane of the present disclosure. Further provided herein is a fuel cell comprising the composite ion exchange membrane of the present disclosure. Further provided herein is an electrochemical hydrogen pump comprising the composite ion exchange membrane of the present disclosure. [Brief explanation of the drawings]

[0027] [Figure 1] Figure 1A is an exploded view of a composite ion exchange membrane of the present disclosure, and Figure 1B shows a different view of the second layer of the composite ion exchange membrane of the present disclosure.

[0028] [Figure 2] FIG. 2 illustrates an exemplary hot welding method for making the composite ion exchange membrane of the present disclosure.

[0029] [Figure 3] FIG. 3 illustrates an exemplary solution casting method for making the composite ion exchange membranes of the present disclosure.

[0030] [Figure 4] FIG. 4 illustrates an exemplary method for adding a catalyst to a gas barrier membrane.

[0031] [Figure 5A] 5A and 5B show an exemplary method for spray coating a catalyst onto a gas barrier membrane (FIG. 5A) and an ion conducting membrane (FIG. 5B). [Figure 5B] 5A and 5B show an exemplary method for spray coating a catalyst onto a gas barrier membrane (FIG. 5A) and an ion conducting membrane (FIG. 5B).

[0032] [Figure 6] FIG. 6 illustrates an exemplary method for fabricating a gas barrier membrane comprising a scaffold.

[0033] [Figure 7] FIG. 7 illustrates an exemplary method for making a composite ion exchange membrane of the present disclosure.

[0034] [Figure 8] FIG. 8 illustrates an exemplary method for preparing a gas barrier membrane for use in the composite ion exchange membrane of the present disclosure.

[0035] [Figure 9] FIG. 9 illustrates an exemplary method for using an optical laser to prepare a gas barrier membrane for use in the composite ion exchange membrane of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0036] Detailed Description A composite ion exchange membrane is described herein.The composite ion exchange membrane provided herein generally comprises a first layer comprising a first ion-conducting membrane, a second layer comprising a gas barrier membrane, and a third layer comprising a second ion-conducting membrane.It has been surprisingly found that by including a gas barrier membrane between two ion-conducting membranes, improved power density can be achieved without excessive mixing of hydrogen and oxygen.Therefore, the composite ion exchange membrane of the present disclosure is thinner and achieves improved power density compared to the ion exchange membranes of the prior art.

[0037] Referring now to FIG. 1 , a composite ion exchange membrane 100 comprises a first layer 110, a second layer 120, and a third layer 130. The first layer 110 includes a first side 112 and a second side 114. The second layer 120 includes a first side 122 and a second side 124. The third layer 130 includes a first side 132 and a second side 134. The second layer 120 is disposed between the first layer 110 and the third layer 130 such that the first side 122 of the second layer 120 is in physical contact with the second side 114 of the first layer 110, and the second side 124 of the second layer 120 is in physical contact with the first side 132 of the third layer 130. Although FIG. 1 shows ion exchange membrane 100 as having a rectangular cross section, the cross section of composite ion exchange membrane 100 of the present disclosure may have any shape, such as circular, oval, triangular, rectangular, pentagonal, hexagonal, etc.

[0038] First layer 110 can have a thickness of about 1 micron to about 50 microns. In some embodiments, first layer 110 can have a thickness of about 1 micron to about 5 microns, about 1 micron to about 10 microns, about 1 micron to about 15 microns, about 1 micron to about 20 microns, about 1 micron to about 25 microns, about 1 micron to about 30 microns, about 1 micron to about 35 microns, about 1 micron to about 40 microns, about 1 micron to about 45 microns, about 1 micron to about 50 microns, about 5 microns to about 50 microns, about 10 microns to about 50 microns, about 15 microns to about 50 microns, about 20 microns to about 50 microns, about 25 microns to about 50 microns, about 30 microns to about 50 microns, about 35 microns to about 50 microns, about 40 microns to about 50 microns, or about 45 microns to about 50 microns. In preferred embodiments, the first layer 100 can have a thickness of from about 5 microns to about 35 microns or from about 10 microns to about 25 microns.

[0039] Second layer 120 can have a thickness of about 1 micron to about 50 microns. In some embodiments, second layer 120 can have a thickness of about 1 micron to about 5 microns, about 1 micron to about 10 microns, about 1 micron to about 15 microns, about 1 micron to about 20 microns, about 1 micron to about 25 microns, about 1 micron to about 30 microns, about 1 micron to about 35 microns, about 1 micron to about 40 microns, about 1 micron to about 45 microns, about 1 micron to about 50 microns, about 5 microns to about 50 microns, about 10 microns to about 50 microns, about 15 microns to about 50 microns, about 20 microns to about 50 microns, about 25 microns to about 50 microns, about 30 microns to about 50 microns, about 35 microns to about 50 microns, about 40 microns to about 50 microns, or about 45 microns to about 50 microns. In preferred embodiments, the second layer 120 can have a thickness of about 5 microns to about 35 microns or about 10 microns to about 25 microns.

[0040] The third layer 130 can have a thickness of about 1 micron to about 50 microns. In some embodiments, the third layer 130 can have a thickness of about 1 micron to about 5 microns, about 1 micron to about 10 microns, about 1 micron to about 15 microns, about 1 micron to about 20 microns, about 1 micron to about 25 microns, about 1 micron to about 30 microns, about 1 micron to about 35 microns, about 1 micron to about 40 microns, about 1 micron to about 45 microns, about 1 micron to about 50 microns, about 5 microns to about 50 microns, about 10 microns to about 50 microns, about 15 microns to about 50 microns, about 20 microns to about 50 microns, about 25 microns to about 50 microns, about 30 microns to about 50 microns, about 35 microns to about 50 microns, about 40 microns to about 50 microns, or about 45 microns to about 50 microns. In a preferred embodiment, the third layer 130 can have a thickness of about 5 microns to about 35 microns or about 10 microns to about 25 microns.

[0041] The first layer 110 and the third layer 130 of the composite ion exchange membrane 100 each comprise an ion-conducting membrane. The ion-conducting membrane is oxidatively stable, and when the ion-conducting membrane is hydrated, the formation of an interconnected network of hydrophilic domains facilitates the movement of ions generated in the electrolysis process, thereby allowing the movement of water and cations. For example, the ion-conducting membrane can transport protons (H + ) and / or hydroxide ions (OH - ) The ion-conducting membrane is preferably cast from an ion-conducting membrane resin. Ion-conducting membranes suitable for use in the present disclosure include any polymer suitable for use in ion exchange membranes.

[0042] Preferably, the ion-conducting membrane comprises a fluorinated polymer. Preferably, the ion-conducting membrane comprises a non-sulfonated polymer. In some embodiments, the ion-conducting membrane can comprise a tetrafluoroethylene-based fluoropolymer-copolymer. In an example, the tetrafluoroethylene-based fluoropolymer-copolymer can be of the formula C7HF 13 O5S·Cn F 2n In another example, the ion-conducting membrane is a Nafion TM It is a membrane.

[0043] The first layer, the third layer, or both may further comprise a catalyst. The catalyst functions to increase the reactivity of hydrogen gas and oxygen gas. Preferably, the catalyst is in the form of nanoparticles, i.e., the catalyst may be in the form of particles having a particle size of about 100 nm or smaller. In a preferred embodiment, the nanoparticles have an average particle size of about 10 nm. The catalyst may comprise one of platinum, palladium, gold, iridium, osmium, rhodium, ruthenium, silver, or a combination thereof.

[0044] In some embodiments, the catalyst may be embedded in the surface of the ion-conducting membrane by a coating technique (e.g., spray coating, blade coating, Meyer rod coating, etc.). When the catalyst is embedded in the surface by coating, the coating composition generally includes the catalyst dispersed in an ion-conducting resin and a suitable solvent. Alternatively, the catalyst may be embedded in the surface of the ion-conducting membrane by reducing a metal salt of the catalyst in situ and performing ion exchange. In such embodiments, the ion-conducting membrane is immersed in a solution containing a metal salt of the catalyst, such as a chloride salt, through a first ion exchange (e.g., a chloroplatinate solution for a platinum catalyst). The metal salt is then reduced by adding a reducing agent, leaving a layer of platinum on the surface of the ion-conducting membrane. The reducing agent may include sodium borohydride, lithium aluminum hydride, sodium thiosulfate, oxalic acid, and other reducing agents known in the art, as well as combinations thereof. A second ion exchange may then be performed to remove reduction by-products from the ion-conducting membrane. Those skilled in the art can determine the appropriate metal salt and reducing agent to use to incorporate the catalyst. By extending the time of ion exchange, the catalyst can be dispersed throughout the ion-conducting membrane.

[0045] In other embodiments, the catalyst may be dispersed throughout the ion-conducting membrane, which may be done by adding the catalyst to the ion-conducting membrane resin before casting the ion-conducting membrane.

[0046] The ion-conducting membrane may further include a scaffold. The scaffold includes a support polymer. The support polymer may be any polymer suitable for providing structural integrity to the membrane without impairing the membrane's suitability for ion exchange. In certain embodiments, the support polymer may include poly(ether ether ketone) (PEEK), polytetrafluoroethylene (PTFE), or polyethylene polyvinylidene fluoride (PVDF). The scaffold may be in the form of a mesh, and the ion-conducting membrane resin is cast onto the scaffold and allowed to dry. Thus, the scaffold is embedded within the ion-conducting membrane.

[0047] The second layer 120 of the composite ion exchange membrane 100 comprises a gas barrier membrane. Gas barrier membranes conduct ions similarly to ion conducting membranes, but are additionally operable to prevent the permeation of hydrogen and oxygen gases into the ion conducting membrane because the solubility of hydrogen and oxygen in gas barrier membranes is much lower than in ion conducting membranes. The gas barrier membrane is preferably cast from a gas barrier, ion conducting resin. The gas barrier membrane comprises a sulfonated polymer. Preferably, the sulfonated polymer is a sulfonated, non-fluorinated polymer. Sulfonated polymers suitable for use in ion exchange membranes are generally known in the art. In a preferred embodiment, the sulfonated polymer is selected from the group consisting of sulfonated poly(ether ether ketone) (SPEEK), sulfonated phenylated poly(phenylene) (SPPP), sulfonated poly(ether sulfone) (SPES), sulfonated polystyrene-b-poly(ethylene-r-butylene)-b-polystyrene (S-SEBS), blends of sulfonated poly(ethylene oxide) blended with poly(vinyl alcohol), sulfonated polystyrene crosslinked with divinylbenzene, and combinations thereof. In a specific example, the sulfonated polymer is selected from the group consisting of SelemionTM CMV, Neosepta TM CMS and Fumasep TM FKS30 or a combination thereof.

[0048] The gas barrier membrane can have an ion exchange capacity of about 0.5 meq / g to about 4.0 meq / g, where meq / g represents the milliequivalent of ion exchange groups contained in 1 gram of dry membrane. In some embodiments, the gas barrier membrane can have an ion exchange capacity of about 0.5 meq / g to about 1.0 meq / g, about 0.5 meq / g to about 1.5 meq / g, about 0.5 meq / g to about 2.0 meq / g, about 0.5 meq / g to about 2.5 meq / g, about 0.5 meq / g to about 3.0 meq / g, about 0.5 meq / g to about 3.5 meq / g, about 0.5 meq / g to about 4.0 meq / g, about 1.0 meq / g to about 4.0 meq / g, about 1.5 meq / g to about 4.0 meq / g, about 2.0 meq / g to about 4.0 meq / g, about 2.5 meq / g to about 4.0 meq / g, about 3.0 meq / g to about 4.0, or about 3.5 meq / g to about 4.0 meq / g.

[0049] The gas barrier membrane can have an ionic conductivity of about 10 mS / cm to about 150 mS / cm. In some embodiments, the gas barrier membrane can have an ionic conductivity of about 10 mS / cm to about 25 mS / cm, about 10 mS / cm to about 50 mS / cm, about 10 mS / cm to about 75 mS / cm, about 10 mS / cm to about 100 mS / cm, about 10 mS / cm to about 125 mS / cm, about 10 mS / cm to about 150 mS / cm, about 25 mS / cm to about 150 mS / cm, about 50 mS / cm to about 150 mS / cm, about 75 mS / cm to about 150 mS / cm, about 100 mS / cm to about 150 mS / cm, or about 125 mS / cm to about 150 mS / cm.

[0050] The second layer may further include a catalyst. The catalyst functions to increase the reactivity of hydrogen gas and oxygen gas. Preferably, the catalyst is in the form of nanoparticles, i.e., the catalyst may be in the form of particles having a particle size of about 100 nm or smaller. In a preferred embodiment, the nanoparticles have an average particle size of about 10 nm. The catalyst may include one of platinum, palladium, gold, iridium, osmium, rhodium, ruthenium, silver, or a combination thereof.

[0051] In some embodiments, the catalyst may be embedded in the surface of the gas barrier membrane by a coating technique (e.g., spray coating, blade coating, Meyer rod coating, etc.). When the catalyst is embedded in the surface by coating, the coating composition generally includes an ion-conductive resin and a catalyst dispersed in a suitable solvent. Alternatively, the catalyst may be embedded in the surface of the gas barrier membrane by reducing a metal salt of the catalyst in situ and performing ion exchange. In such embodiments, the ion-conductive membrane is immersed in a solution containing a metal salt of the catalyst, such as a chloride salt, through a first ion exchange (e.g., a chloroplatinate solution for a platinum catalyst). The metal salt is then reduced by adding a reducing agent, thereby leaving a layer of platinum on the surface of the gas barrier membrane. The reducing agent may include sodium borohydride, lithium aluminum hydride, sodium thiosulfate, oxalic acid, and other reducing agents known in the art, as well as combinations thereof. A second ion exchange may then be performed to remove reduction by-products from the gas barrier membrane. Those skilled in the art can determine the appropriate metal salt and reducing agent to use to incorporate the catalyst. By extending the time of the initial ion exchange, the catalyst can be dispersed throughout the gas barrier membrane.

[0052] In other embodiments, the catalyst may be dispersed throughout the gas barrier membrane, which may be done by adding the catalyst to the gas barrier ion-conducting membrane resin before casting the gas barrier membrane.

[0053] The second layer may further include a scaffold. The scaffold includes a support polymer. The support polymer may be any polymer suitable for providing structural integrity to the membrane without compromising the membrane's suitability for ion exchange. In certain embodiments, the support polymer may include poly(ether ether ketone) (PEEK) or polytetrafluoroethylene (PTFE). The scaffold may be in the form of a mesh, and the gas-barrier, ion-conductive resin is cast onto the scaffold and allowed to dry.

[0054] Turning now to FIG. 1B, the second layer may be a porous second layer 128. That is, the first side 122 and the second side 124 may include a plurality of pores on the surface. The pores are defined by void spaces on the surfaces of each of the first and second sides of the second layer. The pores may each have a depth of about 50 nm to about 1000 nm. The pores may each have a diameter of about 50 nm to about 1000 nm. In embodiments where the second layer 120 is porous, the first layer 110 and the third layer 130 may extend into the pores, such that the second side 114 of the first layer 110 and the first side 132 of the third layer 130 occupy the void spaces of the pores. As described in more detail herein, this arrangement increases surface-to-surface contact of the layers, helping to prevent separation of the layers.

[0055] Alternatively, as shown in FIG. 1B, the second layer can include multiple channels extending across the width of the second layer, thereby forming a second layer having multiple channels 126. Each channel is defined by a void space extending through the second layer from a first side to a second side of the second layer. In such an embodiment, the first layer 110 and the third layer 130 can extend through and occupy the void space in the multiple channels, such that the first layer and the third layer are in physical contact with each of the channels. This further helps prevent layer separation. The channels can have a diameter of about 5 nm to about 1000 nm.

[0056] Those skilled in the art will recognize that the second layer may include multiple channels, multiple pores, or a combination of the two.

[0057] The composite ion exchange membrane of the present disclosure has improved properties compared to ion exchange membranes made of single-ion conductive membranes. In some embodiments, the composite ion exchange membrane of the present disclosure has an improved ion exchange capacity compared to ion exchange membranes made of single-ion conductive membranes. For example, in some embodiments, the composite ion exchange membrane of the present disclosure has an ion exchange capacity that is about 50% to about 60% higher than that of ion exchange membranes made of single-ion conductive membranes.

[0058] In some embodiments, the composite ion exchange membranes of the present disclosure have improved water uptake rates compared to ion exchange membranes composed of single-ion conductive membranes, for example, in some embodiments, the composite ion exchange membranes of the present disclosure have water uptake rates that are at least 50% higher, including up to 100% higher, than ion exchange membranes composed of single-ion conductive membranes.

[0059] In some embodiments, the composite ion exchange membranes of the present disclosure have improved in-plane conductivity compared to ion exchange membranes composed of single-ion conducting membranes, for example, in some embodiments, the composite ion exchange membranes of the present disclosure have in-plane conductivity that is at least 30% higher, including up to 50% higher, than ion exchange membranes composed of single-ion conducting membranes.

[0060] Further described herein is a method for making a composite ion exchange membrane by lamination processing, which generally includes laminating together a first layer comprising a first ion-conducting membrane, a second layer comprising a gas barrier membrane, and a third layer comprising a second ion-conducting membrane, thereby forming the composite ion exchange membrane.

[0061] The lamination step can be performed by any form of lamination process known in the art that is suitable for laminating ion exchange membranes. Preferred methods of lamination include hot welding and solution casting. Preferably, no adhesive is used in the lamination process. However, adhesives may be used to hold the layers of the composite ion exchange membrane together.

[0062] Methods for making composite ion-exchange membranes by hot welding are further described herein. Hot welding, and equipment and systems for performing hot welding, are generally well known in the art. Referring now to FIG. 2, method 200 generally includes hot welding 202 a first layer 110 comprising a first ion-conducting membrane, a second layer 120 comprising a gas barrier membrane, and a third layer 130 comprising a second ion-conducting membrane, thereby forming composite ion-exchange membrane 100. As shown in FIG. 2, the hot welding may be static hot welding. However, roller hot welding and other hot welding methods known in the art may also be used in the methods of the present disclosure.

[0063] Hot pressure welding may be performed at a temperature of about 100°C to about 300°C. In some embodiments, hot pressure welding may be performed at a temperature of about 100°C to about 125°C, about 100°C to about 150°C, about 100°C to about 175°C, about 100°C to about 200°C, about 100°C to about 225°C, about 100°C to about 250°C, about 100°C to about 275°C, about 100°C to about 300°C, about 125°C to about 300°C, about 150°C to about 300°C, about 175°C to about 300°C, about 200°C to about 300°C, about 225°C to about 300°C, about 250°C to about 300°C, or about 275°C to about 300°C. In some examples, hot pressure welding may be performed at a temperature of about 125°C to about 250°C.

[0064] Hot pressure welding may be performed at a pressure of about 100 psi to about 3000 psi. In some embodiments, hot pressure welding may be performed at a pressure of about 100 psi to about 500 psi, about 100 psi to about 1000 psi, about 100 psi to about 1500 psi, about 100 psi to about 2000 psi, about 100 psi to about 2500 psi, about 100 psi to about 3000 psi, about 500 psi to about 3000 psi, about 1000 psi to about 3000 psi, about 1500 psi to about 3000 psi, about 2000 psi to about 3000 psi, about 2500 psi to about 3000 psi, or about 1000 psi to about 2000 psi.

[0065] Hot pressure welding may be performed for about 1 minute to about 10 minutes. In some embodiments, hot pressure welding may be performed for about 1 minute to about 2 minutes, about 1 minute to about 4 minutes, about 1 minute to about 6 minutes, about 1 minute to about 8 minutes, about 1 minute to about 10 minutes, about 2 minutes to about 10 minutes, about 4 minutes to about 10 minutes, about 6 minutes to about 10 minutes, or about 8 minutes to about 10 minutes. In some examples, hot pressure welding may be performed for about 4 minutes to about 6 minutes.

[0066] The method may further include the step of adding a catalyst to the gas barrier film followed by hot welding the layers together. Referring now to FIG. 4, step 400 of adding a catalyst to a gas barrier film 404 may include immersing the gas barrier film 404 in a solution 402 containing a catalyst. The solution may include the catalyst in the form of a catalyst salt. The catalyst may be any catalyst described herein. In a non-limiting example, the catalyst may include platinum and the solution may include chloroplatinic acid (HPtCl). Once the gas barrier film is immersed in the catalyst solution, the catalyst becomes incorporated into the gas barrier film, thus forming a catalyst-doped gas barrier film 406. When the catalyst is added in this manner, the catalyst becomes dispersed throughout the gas barrier film. This step 400 is preferably performed before the hot welding step.

[0067] Alternatively, the catalyst may be added to the gas barrier membrane by spray coating. Referring now to FIG. 5A , step 500 of adding a catalyst to a gas barrier membrane 506 is performed by spraying a catalyst-containing solution 502 using a sprayer 504, thereby forming a catalyst-coated gas barrier membrane 508. The solution 502 may include any catalyst described herein and may be in the form of a catalyst ink. Preferably, the catalyst is in the form of nanoparticles. The solution 502 may be spray-coated onto one or more surfaces of the gas barrier membrane 506 using a sprayer 504, such as an air brush, ultrasonic sprayer, or other device suitable for spray coating known in the art. This step 500 results in a catalyst-coated gas barrier membrane, where the catalyst is embedded in or adhered to the surface of the gas barrier membrane. The catalyst coating may have a thickness of about 0.5 microns on the gas barrier membrane. This step 500 is preferably performed before the hot welding step.

[0068] Additionally, a catalyst may be added to the first ion-conducting membrane and / or the second ion-conducting membrane by spray coating. Referring now to FIG. 5B, step 510 of adding a catalyst to the gas barrier membrane 516 is performed by spraying a catalyst-containing solution 512 using a sprayer 514, thereby forming a catalyst-coated ion-conducting membrane 518. The solution 512 may include any catalyst described herein and may be in the form of a catalyst ink. Preferably, the catalyst is in the form of nanoparticles. The solution 512 may be spray-coated onto one or more surfaces of the ion-conducting membrane 516 using a sprayer 514, such as an air brush, ultrasonic sprayer, or other device suitable for spray coating known in the art. This step 510 results in a catalyst-coated ion-conducting membrane, where the catalyst is embedded in or adhered to the surface of the ion-conducting membrane. The catalyst coating may have a thickness of approximately 0.5 microns on the ion-conducting membrane. This step 510 is preferably performed before the hot-welding step.

[0069] Further provided herein is a method for fabricating a composite ion-exchange membrane by solution casting. Referring now to Figure 3, method 300 generally includes the steps of casting a first layer solution 304 on a substrate 302, drying the first layer solution 304 to form the first layer 110, casting a second layer solution 306 on the first layer 110, drying the second layer solution 306 to form the second layer 120, casting a third layer solution 308 on the second layer 120, and drying the third layer solution 308 to form the third layer 130 (not shown in Figure 3). After drying the third layer 130, the composite ion-exchange membrane 100 is formed.

[0070] The solution for the first layer may comprise a first ion-conductive membrane resin, and the solution for the third layer may comprise a second ion-conductive membrane resin. The ion-conductive membrane resin is a liquid that, when dried, forms the ion-conductive membrane described hereinbefore. The ion-conductive membrane resin may comprise any suitable polymer for use in ion exchange membranes. Preferably, the ion-conductive membrane resin comprises a fluorinated polymer. In some embodiments, the ion-conductive membrane resin may comprise a tetrafluoroethylene-based fluoropolymer-copolymer. In an example, the tetrafluoroethylene-based fluoropolymer-copolymer may be of the formula C7HF 13 O5S·C n F 2n where n is an integer of 3,000 to 10,000.

[0071] The second layer solution may include a gas barrier membrane resin. The gas barrier membrane resin is a liquid that, upon drying, forms the gas barrier membrane of the present disclosure. The gas barrier membrane resin includes a sulfonated polymer. Preferably, the sulfonated polymer is a sulfonated, non-fluorinated polymer. Sulfonated polymers suitable for use in ion exchange membranes are generally known in the art. In a preferred embodiment, the sulfonated polymer is selected from the group consisting of sulfonated poly(ether ether ketone) (SPEEK), sulfonated phenylated poly(phenylene) (SPPP), sulfonated poly(ether sulfone) (SPES), sulfonated polystyrene-b-poly(ethylene-r-butylene)-b-polystyrene (S-SEBS), blends of sulfonated poly(ethylene oxide) mixed with poly(vinyl alcohol), sulfonated polystyrene crosslinked with divinylbenzene, and combinations thereof. In a specific example, the sulfonated polymer is selected from the group consisting of Selemion TM CMV, Neosepta TM CMS and Fumasep TM FKS30 or a combination thereof.

[0072] Each drying step may be carried out at a temperature of about 50° C. to about 100° C. In some embodiments, drying may be carried out at a temperature of about 50° C. to about 60° C., about 50° C. to about 70° C., about 50° C. to about 80° C., about 50° C. to about 90° C., about 50° C. to about 100° C., about 60° C. to about 100° C., about 70° C. to about 100° C., about 80° C. to about 100° C., or about 90° C. to about 100° C. In some examples, drying is carried out at a temperature of about 75° C.

[0073] Drying may occur overnight, or alternatively, drying may occur for a period of about 8 hours to about 24 hours.

[0074] The method may further include adding a catalyst to the first ion-conducting membrane, the second ion-conducting membrane, and / or the gas barrier membrane after each of the first, second, and / or third layers has dried, which may be done by spraying onto the membrane, as described above and shown in Figures 5A and 5B.

[0075] The method may further include placing a scaffold on the first layer prior to casting the second layer solution. Referring now to Figure 6, step 600 includes casting the second layer solution 602 on a scaffold 604. Scaffold 604 may be any scaffold described previously herein.

[0076] Further described herein is a method for preparing the composite ion exchange membrane of the present disclosure by coating. The method generally includes the steps of providing a gas barrier membrane having a first side and a second side opposite the first side, coating the first and second sides of the gas barrier membrane with a pore-former composition including a gas barrier ion-conductive resin and a pore-former, removing the pore-former to form a porous gas barrier membrane, and coating the first and second sides of the gas barrier membrane with an ion-conductive membrane resin to form the composite ion exchange membrane of the present disclosure.

[0077] Turning now to Figure 7, an exemplary process 750 for making a composite ion exchange membrane of the present disclosure is shown. In step 752, a gas barrier membrane 720 is provided, including a first side 722 and a second side 724. The gas barrier membrane 720 is coated with a pore former composition 726. The coating may be performed using a doctor blade, as shown in Figure 7, although other coating methods previously described herein may also be used, so long as a uniform thickness of the pore former composition is achieved.

[0078] Pore ​​former composition 726 comprises or consists of a pore former dispersed in a gas barrier ion-conductive membrane resin, as described previously herein, and a suitable solvent. Preferably, the gas barrier ion-conductive membrane resin has the same chemical identity as gas barrier membrane 720, although in some embodiments, the gas barrier ion-conductive membrane resin has a different chemical identity.

[0079] The pore-forming agent generally comprises one or more polymers capable of remaining suspended in the pore-forming agent composition. Suitable pore-forming agents for use in the present disclosure include polystyrene and polystyrene derivatives, polyethylene oxide and polyethylene oxide derivatives, polyvinylidene fluoride and polyvinylidene fluoride derivatives, carbon black, silica, polyacrylic acid, N-(2-hydroxypropyl)methacrylamide (HPMA), polyacrylamide (PAM), and combinations thereof. The pore-forming agent may have an average particle size of about 50 nm to about 1000 nm.

[0080] The solvent may include any solvent capable of dissolving the gas barrier ion-conducting membrane resin but not the pore-forming agent. In some examples, the solvent may include ethanol, isopropyl alcohol, deionized water, glycerol, ethylene glycol, dimethylacetamide, dimethyl sulfoxide, or a combination thereof.

[0081] The amount of pore-former included in the pore-former composition can be adjusted to control the porosity of the porous gas-barrier membrane. The pore-former can be present in the pore-former composition in a ratio of pore-former to gas-barrier ion-conductive membrane resin, by weight, of about 50:50 to about 90:10. For example, the pore-former can be present in the pore-former composition in a ratio of pore-former to gas-barrier ion-conductive membrane resin of about 50:50 to about 60:40, about 50:50 to about 70:30, about 50:50 to about 80:20, about 50:50 to about 90:10, about 60:40 to about 90:10, about 70:30 to about 90:10, or about 80:20 to about 90:10.

[0082] The pore-former composition may be coated in step 752 at a temperature of about 0° C. to about 120° C. For example, the pore-former composition may be coated at a temperature of about 0° C. to about 20° C., about 0° C. to about 40° C., about 0° C. to about 60° C., about 0° C. to about 80° C., about 0° C. to about 100° C., about 0° C. to about 120° C., about 20° C. to about 120° C., about 40° C. to about 120° C., about 60° C. to about 120° C., about 80° C. to about 120° C., about 100° C. to about 120° C., about 20° C. to about 100° C., or about 40° C. to about 80° C.

[0083] The thickness of the coated pore-former composition can be about 5 μm to about 20 μm on each side of gas barrier membrane 720. For example, the thickness of the coated pore-former composition can be about 5 μm to about 10 μm, about 5 μm to about 15 μm, about 5 μm to about 20 μm, about 10 μm to about 20 μm, or about 15 μm to about 20 μm. Gas barrier membrane 720 can have a thickness as described previously herein.

[0084] In step 754, the coated gas barrier film 720 is dried. The coated gas barrier film may be dried in an oven or any suitable drying apparatus. The gas barrier film 720 may be dried at a temperature of about 25°C to about 120°C at atmospheric pressure. For example, the gas barrier film 720 may be dried at a temperature of about 25°C to about 50°C, about 25°C to about 75°C, about 25°C to about 100°C, about 25°C to about 120°C, about 50°C to about 120°C, about 75°C to about 120°C, about 100°C to about 120°C, or about 50°C to about 100°C.

[0085] In some embodiments, both sides of gas barrier membrane 720 may be coated with the pore former composition in step 752 before drying in step 754. In other embodiments, one side of gas barrier membrane 720 may be coated with the pore former composition in step 752 and then dried in step 754, and then step 752 may be repeated by coating the other side of gas barrier membrane 720 with the pore former composition and then the drying step 754 may be repeated.

[0086] In step 756, the coated gas barrier membrane 720 is immersed in a removal solvent that can dissolve the pore-forming agent but cannot dissolve the gas barrier membrane and the gas barrier ion-conductive membrane resin. Step 756 can be performed by simply immersing the gas barrier membrane 720 in the removal solvent, spraying the removal solvent onto the surface of the gas barrier membrane 720, or otherwise contacting the removal solvent with the gas barrier membrane 720 in an amount sufficient to completely dissolve the pore-forming agent, which may leave the gas barrier membrane 720 free of, or substantially free of, the pore-forming agent. The resulting porous gas barrier membrane has the structure of the porous second layer 128 shown in FIG. 1B.

[0087] The removal solvent may be any solvent capable of dissolving the pore-forming agent but not the gas-barrier, ion-conductive membrane resin. The removal solvent may include a polar organic solvent, a non-polar organic solvent, an aqueous solvent, or a combination thereof. In some examples, the removal solvent may include a hydrocarbon solvent such as toluene or xylene (including meta-, ortho-, and para-xylene), acetone, methanol, water, etc.

[0088] After the removal solvent dissolves the pore-forming agent, porous surfaces remain on the first side 722 and the second side 724 of the gas barrier membrane 720. The porous surfaces can have a thickness of about 1 μm to about 10 μm. The thickness can be uniform across the entire surface of the gas barrier membrane. For example, the porous surfaces can have a thickness of about 1 μm to about 2 μm, about 1 μm to about 4 μm, about 1 μm to about 6 μm, about 1 μm to about 8 μm, about 1 μm to about 10 μm, about 2 μm to about 10 μm, about 4 μm to about 10 μm, about 6 μm to about 10 μm, about 8 μm to about 10 μm, or about 2 μm to about 8 μm.

[0089] In step 758, the coated gas barrier film 720 is dried to remove any residual solvent. The coated gas barrier film may be dried in an oven or any suitable drying apparatus. The gas barrier film 720 may be dried at a temperature of about 25°C to about 120°C at atmospheric pressure. For example, the gas barrier film 720 may be dried at a temperature of about 25°C to about 50°C, about 25°C to about 75°C, about 25°C to about 100°C, about 25°C to about 120°C, about 50°C to about 120°C, about 75°C to about 120°C, about 100°C to about 120°C, or about 50°C to about 100°C.

[0090] In step 760, a first ion-conductive membrane resin is coated on the first side 722 of the gas barrier membrane 720, and a second ion-conductive membrane resin is coated on the second side 724 of the gas barrier membrane 720. The first ion-conductive membrane resin and the second ion-conductive membrane resin can include any of the ion-conductive membrane resins described herein. Preferably, the first ion-conductive membrane resin and the second ion-conductive membrane resin have the same chemical identity, although in some embodiments, the first ion-conductive membrane and the second ion-conductive membrane may have different chemical identities. Once the ion-conductive membrane resins are coated on the first side 722 and the second side 724 of the gas barrier layer, the pores left after removal of the pore-former are filled with the ion-conductive membrane resin.

[0091] The thickness of the first ion-conductive membrane resin and the thickness of the second ion-conductive membrane resin can be any of the thicknesses of the ion-conductive membrane layers described herein. Preferably, the thickness of the first ion-conductive membrane resin is the same as the thickness of the second ion-conductive membrane resin, but in some embodiments, the thickness of the first ion-conductive membrane resin may be different from the thickness of the second ion-conductive membrane resin.

[0092] In step 762, the coated gas barrier membrane 720 is dried to dry the ion-conductive membrane resin, thereby forming a composite ion exchange membrane. The coated gas barrier membrane may be dried in an oven or any suitable drying apparatus. The gas barrier membrane 720 may be dried at a temperature of about 25°C to about 120°C at atmospheric pressure. For example, the gas barrier membrane 720 may be dried at a temperature of about 25°C to about 50°C, about 25°C to about 75°C, about 25°C to about 100°C, about 25°C to about 120°C, about 50°C to about 120°C, about 75°C to about 120°C, about 100°C to about 120°C, or about 50°C to about 100°C.

[0093] In some embodiments, both sides of gas barrier membrane 720 may be coated with ion conductive membrane resin in step 760 before drying in step 762. In other embodiments, one side of gas barrier membrane 720 may be coated with ion conductive membrane resin in step 760, then dried in step 762, and then step 760 may be repeated by coating the other side of gas barrier membrane 720 with ion conductive membrane resin, and then the drying step 762 may be repeated.

[0094] Such methods of making the composite ion exchange membranes of the present disclosure are particularly advantageous because they form pores in the gas barrier membrane 720. In use, the gas barrier membrane 720 swells in the presence of water, thereby increasing contact between the gas barrier membrane 720 and the ion conducting membrane and reducing the likelihood of delamination.

[0095] The present disclosure also describes a method for making a composite ion exchange membrane. The method generally includes the steps of providing a gas barrier membrane having a first side and a second side opposite the first side, forming pores or channels in the gas barrier membrane, and coating the first side and the second side of the gas barrier membrane with an ion-conducting membrane resin, thereby forming the present disclosure's composite ion exchange membrane. The gas barrier membrane can have the chemical identity, thickness, and other properties already discussed herein.

[0096] The pores may be formed as described above for the process shown in FIG. 7 by the use of a pore-forming agent composition.

[0097] In one embodiment, a non-solvent phase separation process may be used to form channels in the gas barrier membrane. Referring now to FIG. 8, process 800 begins at step 802 by providing a gas barrier ion-conducting membrane resin dissolved in a first solvent. The first solvent may include isopropyl alcohol, ethanol, glycerol, ethylene glycol, dimethyl sulfoxide, dimethylacetamide, or any combination thereof. The gas barrier ion-conducting membrane resin may be any gas barrier ion-conducting membrane resin described herein.

[0098] Process 800 proceeds in step 804 by casting a gas barrier ion conducting membrane resin dissolved in a first solvent to form a gas barrier polymer layer, the first solvent remaining encapsulated or embedded within the gas barrier membrane.

[0099] Process 800 proceeds in step 806 by immediately immersing the gas barrier membrane resin in a bath containing a non-solvent. The non-solvent displaces the first solvent in the gas barrier membrane but does not dissolve the gas barrier membrane itself. Once the first solvent is completely displaced, channels and pores remain in the gas barrier membrane. The non-solvent can include water, toluene, xylene, acetone, alcohol (e.g., isopropyl alcohol, n-propyl alcohol, n-octanol), or combinations thereof. Step 806 can be performed for a period of about 1 hour to about 24 hours.

[0100] In step 808, the process concludes by drying the gas barrier film to remove any residual non-solvent. The gas barrier film may be dried at atmospheric pressure at a temperature of about 60° C. to about 120° C. For example, the gas barrier film may be dried at a temperature of about 60° C. to about 80° C., about 60° C. to about 100° C., about 60° C. to about 120° C., about 80° C. to about 120° C., about 100° C. to about 120° C., or about 80° C. to about 100° C.

[0101] Alternatively, the pores or channels may be formed using an optical laser, as shown in Figure 9. This allows for more precise control over the size, depth, and distance between the pores and channels. Optical lasers suitable for producing ion exchange membranes and methods for obtaining them are generally known to those skilled in the art. In a specific, non-limiting example, the laser may be an infrared laser with a wavelength (e.g., about 10 microns), a pulse duration of 5 to 200 microseconds, and an output of about 350 J / cm. 2 The laser may be a carbon dioxide-based laser having a maximum fluence of 1000 .mu.m. One skilled in the art can determine other laser configurations useful for the methods described herein.

[0102] The method 900 includes directing a beam from an optical laser 904 onto a gas barrier membrane 902 to form pores or channels. The optical laser 904 is capable of moving along three axes relative to the gas barrier membrane 902. Thus, the optical laser 904 is capable of controlling the shape, size, and depth of the pores or channels. The optical laser 904 may be programmed to form a predetermined layout of pores or channels.

[0103] After the formation of the pores or channels, a first ion-conductive membrane resin is coated on the first side of the gas barrier membrane, and a second ion-conductive membrane resin is coated on the second side of the gas barrier membrane. The first ion-conductive membrane resin and the second ion-conductive membrane resin can include any of the ion-conductive membrane resins described herein. Preferably, the first ion-conductive membrane resin and the second ion-conductive membrane resin have the same chemical identity, although in some embodiments, the first ion-conductive membrane and the second ion-conductive membrane can have different chemical identities. Once the ion-conductive membrane resins are coated on the first and second sides of the gas barrier layer, the pores remaining after removal of the pore-forming agent are filled with the ion-conductive membrane resin.

[0104] The thickness of the first ion-conductive membrane resin and the thickness of the second ion-conductive membrane resin can be any of the thicknesses of the ion-conductive membrane layers described herein. Preferably, the thickness of the first ion-conductive membrane resin is the same as the thickness of the second ion-conductive membrane resin, but in some embodiments, the thickness of the first ion-conductive membrane resin may be different from the thickness of the second ion-conductive membrane resin.

[0105] The coated gas barrier membrane is then dried to dry the ion-conductive membrane resin, thereby forming a composite ion exchange membrane. The coated gas barrier membrane may be dried in an oven or any suitable drying apparatus. The gas barrier membrane may be dried at a temperature of about 25°C to about 120°C at atmospheric pressure. For example, the gas barrier membrane 720 may be dried at a temperature of about 25°C to about 50°C, about 25°C to about 75°C, about 25°C to about 100°C, about 25°C to about 120°C, about 50°C to about 120°C, about 75°C to about 120°C, about 100°C to about 120°C, or about 50°C to about 100°C.

[0106] In some embodiments, both sides of the gas barrier membrane may be coated with the ion conductive membrane resin in a step before drying in a step. In other embodiments, one side of the gas barrier membrane may be coated with the ion conductive membrane resin in a step, then dried in a step, and then the step may be repeated by coating the other side of the gas barrier membrane with the ion conductive membrane resin, and then the drying step may be repeated.

[0107] Further provided herein is an electrolytic cell comprising the composite ion exchange membrane of the present disclosure. Electrolytic cells and methods for making and obtaining electrolytic cells are generally known to those skilled in the art. Electrolytic cells generally include an anode and a cathode, and the composite ion exchange membrane of the present disclosure is disposed between the anode and the cathode and is in physical contact with the anode and the cathode. Water is supplied to the composite ion exchange membrane, and the potential across the composite ion exchange membrane causes the water to react and produce hydrogen ions at the anode, which flow through the composite ion exchange membrane to the cathode, where the hydrogen ions recombine to form hydrogen gas. The hydrogen gas can then be used for various applications.

[0108] Further provided herein is a fuel cell comprising the composite ion exchange membrane of the present disclosure. Fuel cells and methods for making and obtaining fuel cells are generally known to those skilled in the art. A fuel cell generally includes an anode and a cathode, and the composite ion exchange membrane of the present disclosure is disposed between the anode and the cathode and is in physical contact with the anode and the cathode. Hydrogen gas is supplied to the anode side of the fuel cell, and oxygen gas (often in gaseous form) is supplied to the cathode side of the fuel cell. Electric current is generated by a redox reaction of the hydrogen gas, which splits to form hydrogen ions, which migrate through the composite ion exchange membrane to the cathode of the fuel cell, where the hydrogen ions react with oxygen gas to form water. The electric current is then used to provide electricity.

[0109] Further provided herein is an electrochemical hydrogen pump comprising the composite ion exchange membrane of the present disclosure. Electrochemical hydrogen pumps and methods for making and obtaining them are generally known to those skilled in the art. Electrochemical hydrogen pumps generally include an anode and a cathode, with the composite ion exchange membrane of the present disclosure disposed between and in physical contact with the anode and cathode. A hydrogen recirculation pump can generate protons that can pass from the anode through the composite ion exchange membrane to the cathode to form pressurized hydrogen. Therefore, such electrochemical pumps can be particularly useful for recirculating hydrogen within a system, because at least the electrochemical pumping action provided by the electrochemical pump separates hydrogen from water in a mixture fed to the hydrogen pump through the pump conduit, while also pressurizing the separated hydrogen and facilitating its movement to the inlet portion of the dryer. Enumeration of Embodiments

[0110] Embodiment 1: A composite ion exchange membrane comprising a first layer comprising a first ion-conducting membrane, a second layer comprising a gas barrier membrane, and a third layer comprising a second ion-conducting membrane, wherein the second layer is disposed between the first layer and the third layer such that a first side of the second layer is in physical contact with the first layer and a second side of the second layer opposite the first side is in physical contact with the third layer.

[0111] Embodiment 2: The composite ion exchange membrane of embodiment 1, wherein the first ion-conducting membrane is a tetrafluoroethylene-based fluoropolymer-copolymer.

[0112] Embodiment 3: The tetrafluoroethylene-based fluoropolymer-copolymer has the formula CHF 13 O5S·C n F 2n The composite ion exchange membrane of embodiment 2, wherein n is an integer of 3,000 to 10,000.

[0113] Embodiment 4: The composite ion exchange membrane of any one of embodiments 1 to 3, wherein the second ion-conducting membrane is a tetrafluoroethylene-based fluoropolymer-copolymer.

[0114] Embodiment 5: The tetrafluoroethylene-based fluoropolymer-copolymer has the formula CHF 13 O5S·C n F 2n wherein n is an integer of 3,000 to 10,000.

[0115] Embodiment 6: The composite ion exchange membrane of any one of Embodiments 1 to 5, wherein the first layer has a thickness of from about 1 micron to about 50 microns.

[0116] Embodiment 7: The composite ion exchange membrane of any one of Embodiments 1 to 6, wherein the first layer has a thickness of from about 5 microns to about 35 microns.

[0117] Embodiment 8: The composite ion exchange membrane of any one of Embodiments 1 to 7, wherein the second layer has a thickness of from about 1 micron to about 50 microns.

[0118] Embodiment 9: The composite ion exchange membrane of any one of embodiments 1 to 8, wherein the second layer has a thickness of from about 5 microns to about 35 microns.

[0119] Embodiment 10: The composite ion exchange membrane of any one of Embodiments 1 to 9, wherein the third layer has a thickness of from about 1 micron to about 50 microns.

[0120] Embodiment 11: The composite ion exchange membrane of any one of embodiments 1 to 10, wherein the third layer has a thickness of about 5 microns to about 35 microns.

[0121] Embodiment 12: The composite ion exchange membrane of any one of embodiments 1 to 11, wherein the gas barrier membrane comprises a sulfonated polymer.

[0122] Embodiment 13: The composite ion exchange membrane of embodiment 12, wherein the sulfonated polymer is selected from the group consisting of sulfonated poly(ether ether ketone) (SPEEK), sulfonated phenylated poly(phenylene) (SPPP), sulfonated poly(ether sulfone) (SPES), sulfonated polystyrene-b-poly(ethylene-r-butylene)-b-polystyrene (S-SEBS), a blend of sulfonated poly(ethylene oxide) blended with poly(vinyl alcohol), sulfonated polystyrene crosslinked with divinylbenzene, and any combination thereof.

[0123] Embodiment 14: The composite ion exchange membrane of any one of embodiments 1 to 13, wherein the second layer further comprises a catalyst.

[0124] Embodiment 15: The composite ion exchange membrane of embodiment 14, wherein the catalyst is in the form of nanoparticles.

[0125] Embodiment 16: The composite ion exchange membrane of embodiment 14 or embodiment 15, wherein the catalyst comprises one of platinum, palladium, gold, iridium, osmium, rhodium, ruthenium, silver, or a combination thereof.

[0126] Embodiment 17: The composite ion exchange membrane of any one of Embodiments 14 to 16, wherein the catalyst is embedded in a surface of the gas barrier membrane.

[0127] Embodiment 18: The composite ion exchange membrane of any one of Embodiments 14 to 17, wherein the catalyst is dispersed throughout the gas barrier membrane.

[0128] Embodiment 19: The composite ion exchange membrane of any one of embodiments 1 to 18, wherein the second layer comprises a scaffold.

[0129] Embodiment 20: The composite ion exchange membrane of embodiment 19, wherein the scaffold comprises a supporting polymer.

[0130] Embodiment 21: The composite ion exchange membrane of embodiment 20, wherein the support polymer comprises poly(ether ether ketone) (PEEK).

[0131] Embodiment 22: The composite ion exchange membrane of any one of embodiments 1 to 21, wherein the second layer comprises a plurality of pores on the first side and the second side of the second layer.

[0132] Embodiment 23: The composite ion exchange membrane of embodiment 22, wherein the plurality of pores on the first side of the second layer are occupied by the layer, and the plurality of pores on the second side of the second layer are occupied by the third layer.

[0133] Embodiment 24: The composite ion exchange membrane of any one of embodiments 1 to 23, wherein the second layer comprises a plurality of channels.

[0134] Embodiment 25: The composite ion exchange membrane of embodiment 24, wherein the plurality of channels are occupied by the first layer and the third layer.

[0135] Embodiment 26: A method of making a composite ion exchange membrane, the method comprising hot-pressing a first layer comprising a first ion-conducting membrane, a second layer comprising a gas barrier membrane, and a third layer comprising a second ion-conducting membrane, thereby forming the composite ion exchange membrane.

[0136] Embodiment 27: The method of embodiment 26, wherein the hot welding is performed at a temperature of about 100°C to about 300°C.

[0137] Embodiment 28: The method of embodiment 26 or embodiment 27, wherein the hot welding is performed at a temperature of about 125°C to about 250°C.

[0138] Embodiment 29: The method of any one of embodiments 26-28, wherein the hot welding is performed at a pressure of about 100 psi to about 3000 psi.

[0139] Embodiment 30: The method of any one of embodiments 26-29, wherein the hot welding is performed at a pressure of about 1000 psi to about 2000 psi.

[0140] Embodiment 31: The method of any one of embodiments 26 to 30, wherein the hot welding is performed for about 1 minute to about 10 minutes.

[0141] Embodiment 32: The method of any one of embodiments 26-31, wherein the hot welding is performed for about 4 minutes to about 6 minutes.

[0142] Embodiment 33: The method of any one of embodiments 26 to 32, further comprising the step of immersing the gas barrier membrane in a solution containing a catalyst prior to the hot welding.

[0143] Embodiment 34: The method of embodiment 33, wherein the catalyst is in the form of nanoparticles.

[0144] Embodiment 35: The method of any one of embodiments 26 to 34, further comprising spraying the gas barrier membrane with a solution comprising a catalyst.

[0145] Embodiment 36: The method of embodiment 35, wherein the catalyst is in the form of nanoparticles.

[0146] Embodiment 37: The method of embodiment 35 or embodiment 36, wherein the spraying is performed using an air brush.

[0147] Embodiment 38: The method of embodiment 35 or embodiment 36, wherein the nebulization is performed by ultrasonic nebulization.

[0148] Embodiment 39: The method of any one of embodiments 35-38, wherein the spraying produces a coating on the gas barrier membrane having a thickness of at most 0.5 microns.

[0149] Embodiment 40: The method of any one of embodiments 26 to 39, further comprising spraying the first ion-conducting membrane and / or the second ion-conducting membrane with a solution comprising a catalyst.

[0150] Embodiment 41: The method of embodiment 40, wherein the catalyst is in the form of nanoparticles.

[0151] Embodiment 42: The method of embodiment 40 or embodiment 41, wherein the spraying is performed using an air brush.

[0152] Embodiment 43: The method of embodiment 40 or embodiment 41, wherein the spraying is performed by ultrasonic spraying.

[0153] Embodiment 44: The method of any one of embodiments 40-43, wherein the spraying produces a coating on the first ion-conducting membrane and / or the second ion-conducting membrane having a thickness of at most 0.5 microns.

[0154] Embodiment 45: The method of any one of embodiments 26 to 44, further comprising the step of loading the catalyst onto one or more of the first ion-conducting membrane, the gas barrier membrane, and the second ion-conducting membrane by immersing the first ion-conducting membrane, the gas barrier membrane, or the second ion-conducting membrane in a solution containing a metal salt of the catalyst, and reducing the metal salt of the catalyst in situ.

[0155] Embodiment 46: A method of making a composite ion exchange membrane, the method comprising: casting a first layer solution on a substrate, the first layer solution comprising a first ion-conductive membrane resin; drying the first layer solution to form a first layer; casting a second layer solution on the first layer, the second layer solution comprising a gas barrier membrane resin; and drying the second layer solution to form a second layer; casting a third layer solution on the second layer, the third layer solution comprising a second ion-conductive membrane resin; and drying the third layer solution to form a third layer, thereby forming the composite ion exchange membrane.

[0156] Embodiment 47: The method of embodiment 46, wherein the drying is performed at a temperature of about 50°C to about 100°C.

[0157] Embodiment 48: The method of embodiment 46 or embodiment 47, wherein said drying is performed at a temperature of about 75°C.

[0158] Embodiment 49: The method of any one of embodiments 46-48, wherein the drying is performed overnight.

[0159] Embodiment 50: The method of any one of embodiments 46-49, further comprising spraying the gas barrier membrane with a solution comprising a catalyst.

[0160] Embodiment 51: The method of embodiment 50, wherein the catalyst is in the form of nanoparticles.

[0161] Embodiment 52: The method of embodiment 50 or embodiment 51, wherein the spraying is performed using an air brush.

[0162] Embodiment 53: The method of embodiment 50 or embodiment 51, wherein the spraying is performed by ultrasonic spraying.

[0163] Embodiment 54: The method of any one of embodiments 50-53, wherein the spraying produces a coating on the gas barrier membrane having a thickness of at most 0.5 microns.

[0164] Embodiment 55: The method of any one of embodiments 46-54, further comprising placing a scaffold on the first layer before casting the solution of the second layer.

[0165] Embodiment 56: The method of any one of embodiments 46 to 55, further comprising the step of loading the catalyst onto one or more of the first ion-conducting membrane, the gas barrier membrane, and the second ion-conducting membrane by immersing the first ion-conducting membrane, the gas barrier membrane, or the second ion-conducting membrane in a solution containing a metal salt of the catalyst, and reducing the metal salt of the catalyst in situ.

[0166] Embodiment 57: An electrolytic cell comprising the composite ion exchange membrane of any one of embodiments 1 to 25.

[0167] Embodiment 58: A fuel cell comprising the composite ion exchange membrane of any one of embodiments 1 to 25.

[0168] Embodiment 59: An electrochemical hydrogen pump comprising the composite ion exchange membrane of any one of embodiments 1 to 25.

[0169] Embodiment 60: A method of making a composite ion exchange membrane, the method comprising the steps of providing a gas barrier membrane comprising a first side and a second side opposite the first side; forming pores or channels in the gas barrier membrane; coating the first side of the gas barrier layer and the second side of the gas barrier layer with an ion conductive membrane resin, thereby forming the composite ion exchange membrane.

[0170] Embodiment 61: The method of embodiment 60, wherein the step of forming pores or channels in the gas barrier membrane is performed using an optical laser.

[0171] Embodiment 62: The method of embodiment 60 or embodiment 61, wherein the step of forming pores or channels in the gas barrier membrane comprises coating the first side of the gas barrier membrane and the second side of the gas barrier membrane with a pore former composition, and removing the pore former from the gas barrier membrane, thereby producing a porous gas barrier membrane.

[0172] Embodiment 63: The method of embodiment 62, wherein the pore former composition comprises a gas barrier ion-conducting membrane resin and a pore former.

[0173] Embodiment 64: The method of embodiment 63, wherein the pore-forming agent comprises polystyrene, a derivative of polystyrene, polyethylene oxide, a derivative of polyethylene oxide, polyvinylidene fluoride, a derivative of polyvinylidene fluoride, carbon black, silica, polyacrylic acid, N-(2-hydroxypropyl)methacrylamide (HPMA), polyacrylamide (PAM), or a combination thereof.

[0174] Embodiment 65: The method of any one of embodiments 62 to 64, wherein the pore-former and the gas-barrier ion-conductive membrane resin are present in the pore-former composition in a weight ratio of pore-former to gas-barrier ion-conductive membrane resin of about 50:50 to about 90:10.

[0175] Embodiment 66: The method of any one of embodiments 62-65, further comprising drying the gas barrier membrane after the step of coating the pore-former composition.

[0176] Embodiment 67: The method of embodiment 66, wherein the drying step is carried out at a temperature of from about 25°C to about 120°C.

[0177] Embodiment 68: The method of any one of embodiments 62 to 67, wherein the coated pore-former composition has a thickness of about 5 μm to about 20 μm on each side of the gas barrier membrane.

[0178] Embodiment 69: The method of any one of embodiments 60-68, further comprising drying the ion exchange resin after the step of coating the ion conductive membrane resin.

[0179] Embodiment 70: The method of embodiment 69, wherein the drying step is carried out at a temperature of from about 25°C to about 120°C.

[0180] Embodiment 71: The method of any one of embodiments 60 to 70, further comprising the step of adding a catalyst to the gas barrier membrane, comprising immersing the gas barrier membrane in a solution containing a metal salt of the catalyst, and reducing the metal salt of the catalyst in situ.

[0181] Embodiment 72: A method of making a composite ion exchange membrane, the method comprising the steps of providing a gas barrier membrane including a first side and a second side opposite the first side; coating the first side of the gas barrier membrane and the second side of the gas barrier membrane with a pore former composition; removing the pore former from the gas barrier membrane, thereby producing a porous gas barrier membrane; coating an ion exchange resin on the first side of the gas barrier layer and the second side of the gas barrier layer, thereby forming the composite ion exchange membrane.

[0182] Embodiment 73: A method of making a composite ion exchange membrane, the method comprising: immersing a gas barrier ion-conductive membrane resin containing a first solvent in a non-solvent, such that the non-solvent replaces the first solvent in the gas barrier ion-conductive membrane resin; drying the gas barrier ion-conductive membrane resin to form a gas barrier membrane comprising a first side and a second side, the gas barrier membrane comprising a plurality of pores on the first side and a plurality of pores or channels on the second side; and coating the first side of the gas barrier membrane and the second side of the gas barrier membrane with an ion-conductive membrane resin, thereby forming the composite ion exchange membrane. [Example]

[0183] Example 1 The properties of sulfonated polymers suitable for use in the gas barrier membranes of the present disclosure are presented in Table 1 below. [Table 1]

[0184] All documents cited herein are incorporated herein by reference in their entirety. Unless expressly stated otherwise or clear from the context, reference to a singular item should be understood to include the plural, and vice versa. Grammatical conjunctions are intended to represent any and all disjunctive and conjunctive combinations of connected clauses, sentences, words, etc., unless expressly stated otherwise or clear from the context. Thus, the term "or" should generally be understood to mean "and / or," and the term "and" should generally be understood to mean "and / or."

[0185] The recitation of ranges of values ​​herein is not intended to be limiting, unless otherwise indicated herein, and refers to each and every value falling within that range, rather than individually, and each individual value within such range is incorporated herein as if it were individually recited herein. Words such as "about," "approximately," and the like, when used in conjunction with numerical values, should be interpreted to include any deviation that one of ordinary skill in the art would understand to be sufficient for the intended purpose. Values ​​and / or numerical ranges are presented herein as examples only and do not constitute limitations on the scope of the described embodiments. The use of any and all examples or exemplary language (such as "for example," "etc.", etc.) is intended merely to better clarify the embodiments and does not pose a limitation on the scope of such embodiments. No language herein should be construed as indicating any non-claimed element as essential to the practice of the disclosed embodiments.

[0186] The above-described systems, devices, methods, processes, etc. may be implemented in hardware, software, or any combination thereof suitable for control, data acquisition, and data processing as described herein. This includes implementation in one or more microprocessors, microcontrollers, embedded microcontrollers, programmable digital signal processors, or other programmable devices or processing circuits, with internal and / or external memory. This may also, or instead, include one or more application-specific integrated circuits, programmable gate arrays, programmable array logic components, or any other device(s) that can be configured to process electronic signals. It will further be understood that implementations of the above-described processes or devices may include computer-executable code created using a structured programming language such as C, an object-oriented programming language such as C++, or any other high- or low-level programming language (including assembly language, hardware description languages, and database programming languages ​​and techniques), which may be stored, compiled, or interpreted for execution on one of the above-described devices, as well as heterogeneous combinations of processors, processor architectures, or combinations of different hardware and software. At the same time, processing may be distributed across various system-like devices described above, or all of the functionality may be integrated into a dedicated, standalone device. All such permutations and combinations are intended to fall within the scope of this disclosure.

[0187] Embodiments disclosed herein may include computer program products including computer-executable or computer-usable code that, when executed on one or more computing devices, performs any and / or all of the steps of the above-described control systems. The code may be stored in a non-transitory form in computer memory, which may be memory from which the program executes (such as a random access memory associated with a processor) or a storage device such as a disk drive, flash memory, or any other optical, electromagnetic, magnetic, infrared, or other device or combination of devices. In another aspect, any of the above-described control systems may be embodied in any suitable transmission or propagation medium that conveys the computer-executable code and / or any input or output therefrom.

[0188] The method steps of the implementations described herein, unless a different meaning is expressly provided or otherwise apparent from the context, are intended to include any suitable manner of causing such method steps to be performed, consistent with the patentability of the following claims. Thus, for example, performing step X includes any suitable manner of causing another party, such as a remote user, a remote processing resource (e.g., a server or cloud computer), or a machine, to perform step X. Similarly, performing steps X, Y, and Z may include any manner of directing or controlling any combination of such other individuals or resources to perform steps X, Y, and Z and thereby obtain the benefit of such steps. Thus, the method steps of the implementations described herein, unless a different meaning is expressly provided or otherwise apparent from the context, are intended to include any suitable manner of causing one or more other parties or entities to perform the steps, consistent with the patentability of the following claims. Such parties or entities need not be under the direction or control of any other party or entity, nor need they be located in any particular jurisdiction.

[0189] It is understood that the above methods and systems have been described by way of example and not limitation. Numerous variations, additions, omissions, and other modifications will be apparent to those skilled in the art. Furthermore, the order or presentation of method steps in the above description and drawings is not intended to require such order of performing the recited steps unless a particular order is expressly required or is otherwise apparent from the context. Thus, while specific embodiments have been shown and described, it will be apparent to those skilled in the art that various changes and modifications in form and detail may be made without departing from the scope of the present disclosure. The present invention provides, for example, the following items. (Item 1) a first layer comprising a first ion-conducting membrane; a second layer comprising a gas barrier membrane; and 1. A composite ion exchange membrane comprising a third layer comprising a second ion-conducting membrane, the second layer being disposed between the first layer and the third layer such that a first side of the second layer is in physical contact with the first layer and a second side of the second layer opposite the first side is in physical contact with the third layer. (Item 2) Item 2. The composite ion exchange membrane according to item 1, wherein the first ion-conducting membrane is a tetrafluoroethylene-based fluoropolymer-copolymer. (Item 3) The tetrafluoroethylene-based fluoropolymer-copolymer has the formula CHF 13 O5S·C n F 2n 3. The composite ion exchange membrane according to Item 2, wherein n is an integer of 3,000 to 10,000. (Item 4) Item 10. The composite ion exchange membrane of item 1, wherein the second ion-conducting membrane is a tetrafluoroethylene-based fluoropolymer-copolymer. (Item 5) The tetrafluoroethylene-based fluoropolymer-copolymer has the formula CHF 13O5S·C n F 2n 5. The composite ion exchange membrane according to Item 4, wherein n is an integer of 3,000 to 10,000. (Item 6) Item 2. The composite ion exchange membrane according to item 1, wherein the first layer has a thickness of about 1 micron to about 50 microns. (Item 7) Item 2. The composite ion exchange membrane according to item 1, wherein the first layer has a thickness of about 5 microns to about 35 microns. (Item 8) Item 2. The composite ion exchange membrane according to item 1, wherein the second layer has a thickness of about 1 micron to about 50 microns. (Item 9) Item 2. The composite ion exchange membrane according to item 1, wherein the second layer has a thickness of about 5 microns to about 35 microns. (Item 10) Item 2. The composite ion exchange membrane according to item 1, wherein the third layer has a thickness of about 1 micron to about 50 microns. (Item 11) Item 2. The composite ion exchange membrane according to item 1, wherein the third layer has a thickness of about 5 microns to about 35 microns. (Item 12) Item 10. The composite ion exchange membrane of item 1, wherein the gas barrier membrane comprises a sulfonated polymer. (Item 13) Item 13. The composite ion exchange membrane according to item 12, wherein the sulfonated polymer is selected from the group consisting of sulfonated poly(ether ether ketone) (SPEEK), sulfonated phenylated poly(phenylene) (SPPP), sulfonated poly(ether sulfone) (SPES), sulfonated polystyrene-b-poly(ethylene-r-butylene)-b-polystyrene (S-SEBS), a blend of sulfonated poly(ethylene oxide) blended with poly(vinyl alcohol), sulfonated polystyrene crosslinked with divinylbenzene, and any combination thereof. (Item 14) Item 10. The composite ion exchange membrane of item 1, wherein the second layer further comprises a catalyst. (Item 15) Item 15. The composite ion exchange membrane according to item 14, wherein the catalyst is in the form of nanoparticles. (Item 16) Item 15. The composite ion exchange membrane according to item 14, wherein the catalyst comprises one of platinum, palladium, gold, iridium, osmium, rhodium, ruthenium, silver, or a combination thereof. (Item 17) Item 15. The composite ion exchange membrane according to item 14, wherein the catalyst is embedded in the surface of the gas barrier membrane. (Item 18) Item 15. The composite ion exchange membrane according to item 14, wherein the catalyst is dispersed throughout the gas barrier membrane. (Item 19) Item 10. The composite ion exchange membrane of item 1, wherein the second layer comprises a scaffold. (Item 20) 20. The composite ion exchange membrane according to item 19, wherein the scaffold comprises a supporting polymer. (Item 21) 21. The composite ion exchange membrane of item 20, wherein the support polymer comprises poly(ether ether ketone) (PEEK). (Item 22) Item 10. The composite ion exchange membrane of item 1, wherein the second layer comprises a plurality of pores on the first side and the second side of the second layer. (Item 23) 23. The composite ion exchange membrane of claim 22, wherein the plurality of pores on the first side of the second layer are occupied by the layer and the plurality of pores on the second side of the second layer are occupied by the third layer. (Item 24) Item 10. The composite ion exchange membrane of item 1, wherein the second layer comprises a plurality of channels. (Item 25) 25. The composite ion exchange membrane of claim 24, wherein the plurality of channels are occupied by the first layer and the third layer. (Item 26) 1. A method of making a composite ion exchange membrane, the method comprising hot-pressing a first layer comprising a first ion-conducting membrane, a second layer comprising a gas barrier membrane, and a third layer comprising a second ion-conducting membrane, thereby forming the composite ion exchange membrane. (Item 27) Item 27. The method according to item 26, wherein the hot pressure welding is carried out at a temperature of about 100°C to about 300°C. (Item 28) Item 27. The method according to item 26, wherein the hot welding is carried out at a temperature of about 125°C to about 250°C. (Item 29) Item 27. The method according to item 26, wherein the hot welding is carried out at a pressure of about 100 psi to about 3000 psi. (Item 30) Item 27. The method according to item 26, wherein the hot welding is carried out at a pressure of about 1000 psi to about 2000 psi. (Item 31) Item 27. The method according to item 26, wherein the hot pressure welding is performed for about 1 minute to about 10 minutes. (Item 32) Item 27. The method according to item 26, wherein the hot welding is performed for about 4 minutes to about 6 minutes. (Item 33) 27. The method of claim 26, further comprising the step of immersing the gas barrier membrane in a solution containing a catalyst prior to the hot welding. (Item 34) 34. The method of claim 33, wherein the catalyst is in the form of nanoparticles. (Item 35) 27. The method of claim 26, further comprising spraying the gas barrier membrane with a solution containing a catalyst. (Item 36) 36. The method of claim 35, wherein the catalyst is in the form of nanoparticles. (Item 37) 36. The method of claim 35, wherein the spraying is performed using an air brush. (Item 38) Item 36. The method according to item 35, wherein the atomization is performed by ultrasonic atomization. (Item 39) Item 36. The method of item 35, wherein the spraying produces a coating on the gas barrier film having a thickness of at most 0.5 microns. (Item 40) 27. The method of claim 26, further comprising spraying the first ion-conducting membrane and / or the second ion-conducting membrane with a solution containing a catalyst. (Item 41) 41. The method of claim 40, wherein the catalyst is in the form of nanoparticles. (Item 42) 41. The method of claim 40, wherein the spraying is performed using an air brush. (Item 43) Item 41. The method according to item 40, wherein the atomization is carried out by ultrasonic atomization. (Item 44) Item 41. The method of item 40, wherein the spraying produces a coating on the first ion-conducting membrane and / or the second ion-conducting membrane having a thickness of at most 0.5 microns. (Item 45) immersing the first ion-conductive membrane, the gas barrier membrane, or the second ion-conductive membrane in a solution containing a metal salt of a catalyst; and reducing the metal salt of the catalyst in situ. 27. The method of claim 26, further comprising adding the catalyst to one or more of the first ion-conducting membrane, the gas barrier membrane, and the second ion-conducting membrane by (Item 46) 1. A method for making a composite ion exchange membrane, said method comprising: casting a first layer solution on a substrate, the first layer solution comprising a first ion-conductive membrane resin; drying the first layer solution to form a first layer; casting a solution of a second layer onto the first layer, the solution of the second layer comprising a gas barrier membrane resin; drying the second layer solution to form a second layer; casting a third layer solution onto the second layer, the third layer solution comprising a second ion-conductive membrane resin; drying the third layer solution to form a third layer, thereby forming the composite ion exchange membrane; A method comprising: (Item 47) Item 47. The method according to item 46, wherein the drying is carried out at a temperature of about 50°C to about 100°C. (Item 48) Item 47. The method of item 46, wherein the drying is carried out at a temperature of about 75°C. (Item 49) 47. The method of claim 46, wherein the drying is carried out overnight. (Item 50) Item 47. The method according to item 46, further comprising spraying the gas barrier membrane with a solution containing a catalyst. (Item 51) 51. The method of claim 50, wherein the catalyst is in the form of nanoparticles. (Item 52) 51. The method of claim 50, wherein the spraying is performed using an air brush. (Item 53) 51. The method of claim 50, wherein the atomization is performed by ultrasonic atomization. (Item 54) 51. The method of claim 50, wherein the spraying produces a coating on the gas barrier film having a thickness of at most 0.5 microns. (Item 55) Item 47. The method of item 46, further comprising placing a scaffold on the first layer before casting the solution of the second layer. (Item 56) immersing the first ion-conductive membrane, the gas barrier membrane, or the second ion-conductive membrane in a solution containing a metal salt of a catalyst; and reducing the metal salt of the catalyst in situ. Item 47. The method of claim 46, further comprising adding the catalyst to one or more of the first ion-conducting membrane, the gas barrier membrane, and the second ion-conducting membrane by (Item 57) 26. An electrolytic cell comprising the composite ion exchange membrane according to any one of items 1 to 25. (Item 58) 26. A fuel cell comprising the composite ion exchange membrane according to any one of items 1 to 25. (Item 59) 26. An electrochemical hydrogen pump comprising the composite ion exchange membrane according to any one of items 1 to 25. (Item 60) 1. A method for making a composite ion exchange membrane, said method comprising: providing a gas barrier membrane comprising a first side and a second side opposite the first side; forming pores or channels in the gas barrier membrane; coating the first side of the gas barrier layer and the second side of the gas barrier layer with an ion-conductive membrane resin, thereby forming the composite ion exchange membrane. A method comprising: (Item 61) Item 61. The method of item 60, wherein the step of forming pores or channels in the gas barrier membrane is performed using an optical laser. (Item 62) forming pores or channels in the gas barrier membrane; coating the first side of the gas barrier membrane and the second side of the gas barrier membrane with a pore-former composition; and removing the pore-forming agent from the gas barrier membrane, thereby forming a porous gas barrier membrane. Item 61. The method according to Item 60, comprising: (Item 63) Item 63. The method of claim 62, wherein the pore former composition comprises a gas barrier ion-conducting membrane resin and a pore former. (Item 64) Item 64. The method of item 63, wherein the pore-forming agent comprises polystyrene, derivatives of polystyrene, polyethylene oxide, derivatives of polyethylene oxide, polyvinylidene fluoride, derivatives of polyvinylidene fluoride, carbon black, silica, polyacrylic acid, N-(2-hydroxypropyl)methacrylamide (HPMA), polyacrylamide (PAM), or a combination thereof. (Item 65) Item 63. The method of item 62, wherein the pore-former and the gas-barrier ion-conductive membrane resin are present in the pore-former composition in a weight ratio of pore-former to gas-barrier ion-conductive membrane resin of about 50:50 to about 90:10. (Item 66) Item 63. The method of claim 62, further comprising the step of drying the gas barrier membrane after the step of coating the pore-forming agent composition. (Item 67) Item 67. The method according to item 66, wherein the drying step is carried out at a temperature of about 25°C to about 120°C. (Item 68) Item 63. The method of item 62, wherein the coated pore-forming composition has a thickness of about 5 μm to about 20 μm on each side of the gas barrier membrane. (Item 69) Item 61. The method of claim 60, further comprising the step of drying the ion exchange resin after the step of coating the ion conductive membrane resin. (Item 70) Item 70. The method according to item 69, wherein the drying step is carried out at a temperature of about 25°C to about 120°C. (Item 71) Item 61. The method according to item 60, further comprising adding a catalyst to the gas barrier membrane, immersing the gas barrier membrane in a solution containing a metal salt of the catalyst; and reducing the metal salt of the catalyst in situ; A method comprising: (Item 72) 1. A method for making a composite ion exchange membrane, said method comprising: providing a gas barrier membrane comprising a first side and a second side opposite the first side; coating the first side of the gas barrier membrane and the second side of the gas barrier membrane with a pore-former composition; removing the pore-forming agent from the gas barrier membrane, thereby producing a porous gas barrier membrane; coating an ion exchange resin on the first side of the gas barrier layer and on the second side of the gas barrier layer, thereby forming the composite ion exchange membrane. A method comprising: (Item 73) 1. A method for making a composite ion exchange membrane, said method comprising: immersing a gas barrier ion-conductive membrane resin containing a first solvent in a non-solvent, so that the non-solvent replaces the first solvent in the gas barrier ion-conductive membrane resin; drying the gas barrier ion-conductive membrane resin to form a gas barrier membrane having a first side and a second side, the gas barrier membrane comprising a plurality of pores on the first side and a plurality of pores or a plurality of channels on the second side; coating the first side of the gas barrier membrane and the second side of the gas barrier membrane with an ion-conductive membrane resin, thereby forming the composite ion exchange membrane; A method comprising:

Claims

1. a first layer comprising a first ion-conductive membrane cast from an ion-conductive membrane resin; a second layer comprising a gas barrier membrane cast from an ion-conductive membrane resin; and 1. A composite ion exchange membrane comprising a third layer including a second ion-conducting membrane cast from an ion-conducting membrane resin, the second layer being disposed between the first layer and the third layer such that a first side of the second layer is in physical contact with the first layer and a second side of the second layer opposite the first side is in physical contact with the third layer.

2. 2. The composite ion exchange membrane of claim 1, wherein the first ion-conducting membrane is a tetrafluoroethylene-based fluoropolymer-copolymer.

3. The tetrafluoroethylene-based fluoropolymer-copolymer is of formula C ７ HF １３ O ５ S.C. ｎ F ２ｎ 3. The composite ion exchange membrane according to claim 2, wherein n is an integer of 3,000 to 10,000.

4. 2. The composite ion exchange membrane of claim 1, wherein the second ion-conducting membrane is a tetrafluoroethylene-based fluoropolymer-copolymer.

5. The tetrafluoroethylene-based fluoropolymer-copolymer is of formula C ７ HF １３ O ５ S.C. ｎ F ２ｎ 5. The composite ion exchange membrane according to claim 4, wherein n is an integer of 3,000 to 10,000.

6. 10. The composite ion exchange membrane of claim 1, wherein the first layer has a thickness of from about 1 micron to about 50 microns.

7. 10. The composite ion exchange membrane of claim 1, wherein the first layer has a thickness of from about 5 microns to about 35 microns.

8. 10. The composite ion exchange membrane of claim 1, wherein said second layer has a thickness of from about 1 micron to about 50 microns.

9. 10. The composite ion exchange membrane of claim 1, wherein the second layer has a thickness of from about 5 microns to about 35 microns.

10. 10. The composite ion exchange membrane of claim 1, wherein said third layer has a thickness of from about 1 micron to about 50 microns.

11. 10. The composite ion exchange membrane of claim 1, wherein said third layer has a thickness of from about 5 microns to about 35 microns.

12. The composite ion exchange membrane of claim 1 , wherein the gas barrier membrane comprises a sulfonated polymer.

13. 13. The composite ion exchange membrane of claim 12, wherein the sulfonated polymer is selected from the group consisting of sulfonated poly(ether ether ketone) (SPEEK), sulfonated phenylated poly(phenylene) (SPPP), sulfonated poly(ether sulfone) (SPES), sulfonated polystyrene-b-poly(ethylene-r-butylene)-b-polystyrene (S-SEBS), a blend of sulfonated poly(ethylene oxide) blended with poly(vinyl alcohol), sulfonated polystyrene crosslinked with divinylbenzene, and any combination thereof.

14. The composite ion exchange membrane of claim 1 , wherein the second layer further comprises a catalyst.

15. 15. The composite ion exchange membrane of claim 14, wherein the catalyst is in the form of nanoparticles.

16. 15. The composite ion exchange membrane of claim 14, wherein the catalyst comprises one of platinum, palladium, gold, iridium, osmium, rhodium, ruthenium, silver, or a combination thereof.

17. 15. The composite ion exchange membrane of claim 14, wherein the catalyst is embedded in the surface of the gas barrier membrane.

18. 15. The composite ion exchange membrane of claim 14, wherein the catalyst is dispersed throughout the gas barrier membrane.

19. The composite ion exchange membrane of claim 1 , wherein the second layer comprises a scaffold.

20. 20. The composite ion exchange membrane of claim 19, wherein the scaffold comprises a supporting polymer.

21. 21. The composite ion exchange membrane of claim 20, wherein the support polymer comprises poly(ether ether ketone) (PEEK).

22. 10. The composite ion exchange membrane of claim 1, wherein said second layer comprises a plurality of pores on said first side and said second side of said second layer.

23. 23. The composite ion exchange membrane of claim 22, wherein the plurality of pores on the first side of the second layer are occupied by the layer and the plurality of pores on the second side of the second layer are occupied by the third layer.

24. The composite ion exchange membrane of claim 1 , wherein the second layer comprises a plurality of channels.

25. 25. The composite ion exchange membrane of claim 24, wherein said plurality of channels are occupied by said first layer and said third layer.

26. 1. A method of making a composite ion exchange membrane, the method comprising hot-pressing a first layer comprising a first ion-conducting membrane, a second layer comprising a gas barrier membrane, and a third layer comprising a second ion-conducting membrane, thereby forming the composite ion exchange membrane.

27. 27. The method of claim 26, wherein the hot welding is performed at a temperature of about 100°C to about 300°C.

28. 27. The method of claim 26, wherein the hot welding is performed at a temperature of about 125°C to about 250°C.

29. The method of claim 26, wherein the hot welding is performed at a pressure of about 100 psi to about 3000 psi.

30. The method of claim 26, wherein the hot welding is performed at a pressure of about 1000 psi to about 2000 psi.

31. The method of claim 26, wherein the hot welding is performed for about 1 minute to about 10 minutes.

32. 27. The method of claim 26, wherein the hot welding is performed for about 4 minutes to about 6 minutes.

33. 27. The method of claim 26, further comprising the step of immersing the gas barrier membrane in a solution containing a catalyst prior to the hot welding.

34. 34. The method of claim 33, wherein the catalyst is in the form of nanoparticles.

35. 27. The method of claim 26, further comprising spraying the gas barrier membrane with a solution containing a catalyst.

36. 36. The method of claim 35, wherein the catalyst is in the form of nanoparticles.

37. 36. The method of claim 35, wherein the spraying is performed with an air brush.

38. 36. The method of claim 35, wherein the atomization is performed by ultrasonic atomization.

39. 36. The method of claim 35, wherein the spraying produces a coating on the gas barrier film having a thickness of at most 0.5 microns.

40. 27. The method of claim 26, further comprising spraying the first ion-conducting membrane and / or the second ion-conducting membrane with a solution containing a catalyst.

41. 41. The method of claim 40, wherein the catalyst is in the form of nanoparticles.

42. 41. The method of claim 40, wherein the spraying is performed with an air brush.

43. 41. The method of claim 40, wherein the atomization is performed by ultrasonic atomization.

44. 41. The method of claim 40, wherein the spraying produces a coating on the first ion-conducting membrane and / or the second ion-conducting membrane having a thickness of at most 0.5 microns.

45. immersing the first ion-conductive membrane, the gas barrier membrane, or the second ion-conductive membrane in a solution containing a metal salt of a catalyst; and reducing the metal salt of the catalyst in situ.

27. The method of claim 26, further comprising adding the catalyst to one or more of the first ion-conducting membrane, the gas barrier membrane, and the second ion-conducting membrane by

46. 1. A method for making a composite ion exchange membrane, said method comprising: Casting a first layer solution onto a substrate, the first layer solution comprising a first ion-conductive membrane resin; drying the first layer solution to form a first layer; casting a solution of a second layer onto the first layer, the solution of the second layer comprising a gas barrier membrane resin; drying the second layer solution to form a second layer; casting a third layer solution onto the second layer, the third layer solution comprising a second ion-conductive membrane resin; drying the third layer solution to form a third layer, thereby forming the composite ion exchange membrane; A method comprising:

47. 47. The method of claim 46, wherein the drying is carried out at a temperature of from about 50°C to about 100°C.

48. 47. The method of claim 46, wherein the drying is carried out at a temperature of about 75°C.

49. 47. The method of claim 46, wherein the drying is carried out overnight.

50. 47. The method of claim 46, further comprising spraying the gas barrier membrane with a solution containing a catalyst.

51. 51. The method of claim 50, wherein the catalyst is in the form of nanoparticles.

52. 51. The method of claim 50, wherein the spraying is performed with an air brush.

53. 51. The method of claim 50, wherein the atomization is performed by ultrasonic atomization.

54. 51. The method of claim 50, wherein the spraying produces a coating on the gas barrier film having a thickness of at most 0.5 microns.

55. 47. The method of claim 46, further comprising placing a scaffold on the first layer prior to casting the second layer solution.

56. immersing the first ion-conductive membrane, the gas barrier membrane, or the second ion-conductive membrane in a solution containing a metal salt of a catalyst; and reducing the metal salt of the catalyst in situ.

47. The method of claim 46, further comprising adding the catalyst to one or more of the first ion-conducting membrane, the gas barrier membrane, and the second ion-conducting membrane by

57. An electrolytic cell comprising the composite ion exchange membrane according to any one of claims 1 to 25.

58. A fuel cell comprising the composite ion exchange membrane according to any one of claims 1 to 25.

59. An electrochemical hydrogen pump comprising the composite ion exchange membrane according to any one of claims 1 to 25.

60. 1. A method for making a composite ion exchange membrane, said method comprising: providing a gas barrier membrane comprising a first side and a second side opposite the first side; forming pores or channels in the gas barrier membrane; coating an ion-conductive membrane resin on the first side of the gas barrier layer and on the second side of the gas barrier layer, thereby forming the composite ion exchange membrane. A method comprising:

61. 61. The method of claim 60, wherein the step of forming pores or channels in the gas barrier membrane is performed using an optical laser.

62. forming pores or channels in the gas barrier membrane; coating the first side of the gas barrier membrane and the second side of the gas barrier membrane with a pore former composition; and removing the pore-forming agent from the gas barrier membrane, thereby forming a porous gas barrier membrane.

61. The method of claim 60, comprising:

63. 63. The method of claim 62, wherein the pore former composition comprises a gas barrier ion-conducting membrane resin and a pore former.

64. 64. The method of claim 63, wherein the pore-forming agent comprises polystyrene, derivatives of polystyrene, polyethylene oxide, derivatives of polyethylene oxide, polyvinylidene fluoride, derivatives of polyvinylidene fluoride, carbon black, silica, polyacrylic acid, N-(2-hydroxypropyl)methacrylamide (HPMA), polyacrylamide (PAM), or combinations thereof.

65. 63. The method of claim 62, wherein the pore-former and the gas barrier ion-conductive membrane resin are present in the pore-former composition in a weight ratio of pore-former to gas barrier ion-conductive membrane resin of about 50:50 to about 90:

10.

66. 63. The method of claim 62, further comprising the step of drying the gas barrier membrane after the step of coating the pore-former composition.

67. 67. The method of claim 66, wherein the drying step is carried out at a temperature of from about 25°C to about 120°C.

68. 63. The method of claim 62, wherein the coated pore former composition has a thickness of about 5 μm to about 20 μm on each side of the gas barrier membrane.

69. 61. The method of claim 60, further comprising the step of drying the ion exchange resin after the step of coating the ion conductive membrane resin.

70. 70. The method of claim 69, wherein the drying step is carried out at a temperature of from about 25°C to about 120°C.

71. 61. The method of claim 60, further comprising adding a catalyst to the gas barrier membrane, immersing the gas barrier membrane in a solution containing a metal salt of the catalyst; and reducing the metal salt of the catalyst in situ; A method comprising:

72. 1. A method for making a composite ion exchange membrane, said method comprising: providing a gas barrier membrane comprising a first side and a second side opposite the first side; coating the first side of the gas barrier membrane and the second side of the gas barrier membrane with a pore former composition; removing the pore-forming agent from the gas barrier membrane, thereby producing a porous gas barrier membrane; coating an ion exchange resin on the first side of the gas barrier layer and on the second side of the gas barrier layer, thereby forming the composite ion exchange membrane. A method comprising:

73. 1. A method for making a composite ion exchange membrane, said method comprising: immersing a gas barrier ion-conductive membrane resin containing a first solvent in a non-solvent, so that the non-solvent replaces the first solvent in the gas barrier ion-conductive membrane resin; drying the gas barrier ion-conductive membrane resin to form a gas barrier membrane having a first side and a second side, the gas barrier membrane comprising a plurality of pores on the first side and a plurality of pores or a plurality of channels on the second side; coating the first side of the gas barrier membrane and the second side of the gas barrier membrane with an ion-conductive membrane resin, thereby forming the composite ion exchange membrane; A method comprising:

Images