Fuel cell membrane electrode assembly and fuel cell

Abstract

Fuel cell membrane electrode arrangement (1, 10) comprising: - a support material (5) comprising a ceramic material (6) and iridium oxide (8), wherein - the weight fraction of iridium oxide (8), based on metallic iridium, in relation to the total weight of the support material (5), is at most 50 wt.%, and wherein - the support material exhibits a weight loss of less than 3 wt.%, based on the weight fraction of iridium oxide (8), when the support material is exposed for 12 hours at a temperature of 80 °C to a 3.3 vol.a % hydrogen stream in argon, characterized in that the support material (5) is present in an anode (4) of the fuel cell membrane electrode assembly (1) and the anode (4) further comprises at least one ionomer (14) and a hydrogen oxidation catalyst (9), wherein the hydrogen oxidation catalyst (9) comprises particles of platinum and / or a platinum alloy arranged on the support material (5) and / or is present in a barrier layer (11) arranged between an anode (4) and a gas diffusion layer (12) of the fuel cell membrane electrode assembly (10), wherein the barrier layer (11) further comprises at least one polymeric binder (13), wherein the basis weight of iridium oxide (8), based on metallic iridium, in the barrier layer and / or the anode (11) is less than 0.03 mgIr / cm2.

Description

[0001] The invention relates to a fuel cell membrane electrode arrangement and a fuel cell with improved cell reversal tolerance.

[0002] During fuel cell operation, high potentials can occur on the anode of a membrane electrode assembly (MEA) if there is an insufficient amount of fuel and a certain current is drawn simultaneously, thus reversing the fuel cell voltage. This phenomenon is commonly referred to as "fuel depletion" or "cell reversal." Under these high potentials, the carbon of the anode catalyst, which is typically used as a support material for platinum-based catalysts in the anode, oxidizes (corrodes), and the MEA degrades.

[0003] To solve this problem, various approaches are described in the prior art. For example, highly graphitized carbons can be used as the support material for the platinum catalyst, as these exhibit higher corrosion stability than non-graphitized carbons. The anode can also contain, in addition to the hydrogen oxidation catalyst (HOR), a catalyst composition for oxygen evolution (OER) to provide the required current through the oxidation of water to oxygen, thereby protecting the carbon from oxidation. Although the described measures already improve the so-called "cell reversal tolerance" (CRT), they are not yet sufficient to achieve the required cell reversal tolerance.If fuel depletion occurs too frequently or too regularly, the carbon of the anode catalyst can continue to corrode, the MEA can fail, and consequently, the entire fuel cell can fail. Furthermore, the OER catalyst, usually based on IrO2, can disintegrate under repeated cycles between low and high potentials at the anode, such as those occurring under cell reversal conditions or during air-air fuel cell start-ups (so-called "air-air starts"), thus losing its ability to protect the anodes.

[0004] In addition to the aforementioned measures, carbon-free electrodes have also been proposed to improve corrosion stability. These electrodes consist of platinum catalyst particles on a non-conductive support material, such as titanium dioxide, and the anode incorporates a finely dispersed, conductive ceramic to ensure sufficient conductivity. Such a system is proposed, for example, in US 7677330 A. However, these conductive ceramics, used as support material or as additives, do not exhibit sufficient corrosion stability and tend to dissolve, particularly in the highly acidic environment of a fuel cell. This leads to significant power losses and potentially to contamination of the MEA.

[0005] The object of the present invention is to provide a fuel cell membrane electrode arrangement and a fuel cell which, in addition to high power density, high long-term stability and simple and reliable manufacturability, are characterized by a high cell reversal tolerance.

[0006] The problem is solved by the subject matter of the independent claims. The dependent claims contain advantageous further developments and embodiments of the invention.

[0007] Accordingly, the problem is solved by a fuel cell membrane electrode assembly (fuel cell MEA) comprising a specifically designed support material. The support material comprises a ceramic material and a weight fraction of iridium oxide, based on metallic iridium and further based on the total weight of the support material, of no more than 50 wt.%, wherein the ceramic material is present, in particular, in the form of particles or fibers. The iridium oxide can optionally be present as a mixture with other oxides (hereinafter referred to as iridium oxide) and is, in particular, deposited on the ceramic material. The iridium oxide exhibits stability against reduction in hydrogen, which is characterized by a weight loss of the support material of less than 3 wt.% based on the weight fraction of the contained iridium oxide in a hydrogen atmosphere.

[0008] According to the invention, the reduction stability of the catalyst is determined by measuring the mass loss or weight loss of the OER catalyst under the influence of a hydrogen flow at elevated temperature. For this purpose, a thermogravimetric analysis (TGA) is carried out in a reductive atmosphere. The thermogravimetric analysis of the OER catalyst powder is performed using a Mettler Toledo TGA / DSC 1 apparatus. Approximately 10 to 12 mg of the OER catalyst powder are weighed into a corundum crucible (volume: 70 µL), sealed with a perforated corundum lid, and placed directly into the TGA furnace. All gases used in the thermogravimetric analysis are of 5.0 purity and are distributed by Westfalen AG. Argon (20 mL / min) -1 ) is used as a cell carrier gas in addition to hydrogen.

[0009] Each TGA measurement is divided into steps: i) in-situ drying step in an oxidizing atmosphere and ii) Metal oxide reduction step in a reducing atmosphere.

[0010] The in-situ drying step is used to desorb all water molecules and organic molecules adsorbed on the surface of the OER catalyst powder, so that the weight loss in step ii) is solely due to the reduction of iridium oxide.

[0011] The in-situ drying step is carried out as follows: first, the TGA oven is purged with argon for 5 minutes at a temperature of 25 °C (100 mL / min). -1 ), then the temperature is increased from 25 to 200 °C (10 Kmin) -1 ) in O2 (100 mLmin -1 The temperature of 200 °C is maintained for 10 minutes in O2 (100 mL / min). -1 ). Then the oven temperature is reduced from 200 to 25 °C (-10 Kmin). -1 ) in O2 (100 mLmin -1) cooled down and finally the TGA furnace is filled with argon (100 mLmin) -1 Rinsed for 5 minutes at 25°C.

[0012] During the metal oxide reduction step ii), the furnace is heated from 25 °C to 80 °C at a heating rate of 5 Kmin. -1 in argon (100 mLmin -1 ) heated, followed by a gas exchange to 3.3 vol.% H2 / Ar (40 mLmin) -1 ) and maintained at 80 °C for 12 hours. Afterwards, the oven temperature was reduced from 80 °C to 25 °C (cooling rate: -20 Kmin). -1 ) in Ar (100 mLmin -1 ) cooled down.

[0013] If the support material comprises, for example, 30 wt% IrO₂, the weight loss of the support material in H₂ is less than 0.9 wt%, provided that the ceramic material is selected to exhibit virtually no weight loss under these conditions. The reduction stability of the iridium oxide in the hydrogen environment is achieved by heat treatment, in other words, by annealing the support material at sufficiently high temperatures above 400 °C, preferably above 450 °C, and more preferably above 500 °C.

[0014] According to one embodiment, the support material is located in an anode of the fuel cell membrane electrode assembly, and the anode further comprises at least one ionomer and a hydrogen oxidation catalyst, wherein the hydrogen oxidation catalyst comprises particles of platinum and / or a platinum alloy arranged on the support material. In particular, the hydrogen oxidation catalyst is arranged on the surface of the support material, wherein the hydrogen oxidation catalyst and the ionomer are very well mixed. The hydrogen oxidation catalyst can be arranged on the iridium oxide and / or on the ceramic material.

[0015] The above arrangement results in a high power density. This is achieved in particular by a very fine distribution of the platinum and / or platinum alloy particles of the hydrogen oxidation catalyst on the iridium oxide support material and the ceramic material, thereby ensuring good platinum utilization.

[0016] In an alternative or additive embodiment, the support material is present in a barrier layer arranged between an anode and a gas diffusion layer of the fuel cell membrane electrode assembly, the barrier layer further comprising at least one polymeric binder. Due to the use of the specifically designed support material, the barrier layer is characterized by excellent and reliable manufacturability, high functionality, in particular high long-term stability, and low cost, and enables excellent cell reversal tolerance of the fuel cell MEA.

[0017] In the above-described processes, the use of a stable iridium oxide is particularly important, as it neither dissolves nor loses its OER properties under repeated potential cycles of the anode between low and high potentials. This stability is achieved by heat-treating the support material at high temperatures, which makes the iridium oxide resistant to reduction by hydrogen. In addition to improving stability, the heat treatment of the iridium oxide also reduces the OER activity, both by reducing the surface area and by altering the crystal structure.However, due to the fact that essentially no carbon-based materials are present in the layer where the support material is deployed, the cell reversal tolerance is excellent, even if the OER activity of the iridium oxide does not reach its maximum possible value. In other words, the long-term maintenance of the iridium oxide's activity, i.e., its long-term stability, is more important than its initial OER activity, since the anode and / or barrier layer are essentially free of carbon and / or carbon-containing supports. "Essentially free of carbon and / or carbon-containing supports" means that no carbon or carbon-containing compounds are added to the anode and / or barrier layer. Typically, the carbon-containing supports are not polymeric compounds.

[0018] In the absence of carbon materials, the electrical conductivity of the layers is ensured by the metals or metal oxides, in particular by iridium oxide and platinum in the anode layer, as well as the iridium oxide in the barrier layer. Consequently, neither electrically conductive carbon-containing materials, such as carbon black or graphite, are used in the anode nor in any barrier layer that may be present. To achieve good conductivity and, accordingly, good cell performance, the metal content of electrically conductive metal compounds, based on the total weight of the layer's components (weight ratio of the sum of the metals to the sum of metals, oxides, and ceramic materials), should be sufficiently high, at least 15 wt.% and preferably at least 30 wt.%.

[0019] The support material for producing the anode according to the invention and the support material for producing the barrier layer according to the invention are characterized by the same properties as described above, but within the scope of the claims, they can have different parameters within a fuel cell MEA, such as with regard to the weight fraction of iridium, crystallinity of the iridium compound, chemical composition of the ceramic material, or BET surface of the ceramic material.

[0020] In the fuel cell MEA according to the invention, as already explained above, a high cell reversal tolerance is achieved, which is particularly due to the fact that carbon materials in the anode and in the barrier layer are dispensed with and, in addition, the iridium oxide in the support material acts as an oxygen evolution catalyst, which oxidizes water to oxygen, which limits the potential of the anode in the event of fuel depletion and thus reduces the anode stress.

[0021] According to a further advantageous embodiment, iridium oxide, due to its very good electrical conductivity and high degradation stability, exists as a mixture or alloy with other metal oxides. Examples of metal oxides that can exist as a mixture or alloy with iridium oxide are RuO₂, SnO₂, and Ta₂O₅, resulting in mixed oxides with the molecular formulas Ir x Ru( 1-x )O2, Ir x Sn( 1-x)O2, or IrO2-Ta2O5, can be obtained. However, iridium oxide should constitute the main component, and thus a weight fraction, based on the total weight of the mixture or alloy, of more than 50 wt.% and, in particular, more than 75 wt.% to ensure good OER activity and stability of the support material. Preferably, iridium oxide is used essentially as a pure oxide with the molecular formula IrO2. The iridium oxide is arranged on the surface of the ceramic material and at least partially covers it.

[0022] The resulting conductivity of the support material, as well as of the electrocatalyst obtained by platinum or platinum alloy deposition, can be verified by powder conductivity measurements. Furthermore, the electrical resistivity within the electrode can be verified, for example, in a four-point measurement or directly in the fuel cell application by impedance measurement or measurement of polarization curves. The thermal treatment of the support material leads, on the one hand, to the crystallization of the iridium oxide into a highly crystalline structure with very high electrical conductivity. On the other hand, the thermal treatment of the support material can lead to agglomeration into larger particles of iridium oxide, which are thus separated from one another, resulting in insufficient percolation pathways for electrons.The best compromise between thermal treatment and amount of metal, which still depends on the type of ceramic material used, can be identified by a person skilled in the art through appropriate experimental design within the previously defined limits.

[0023] For cost savings, a further advantageous embodiment provides that the iridium oxide (based on metallic iridium) has a weight fraction of at most 35 wt.% and, more preferably, at most 25 wt.% relative to the total weight of the substrate material. Such low iridium weight fractions ensure sufficient layer thickness even with a low iridium oxide loading (amount of iridium per geometric area) by using an inert component in the form of the ceramic material, thus facilitating the production of these layers using known coating techniques such as doctor blade application, spatter coating, slot die coating, screen printing, gravure printing, etc. Therefore, even with these very low iridium contents, a reliable and, in particular, complete coating of the ceramic material with iridium oxide can be achieved.

[0024] Furthermore, it is advantageously provided that the basis weight of iridium oxide in the barrier layer and / or in the anode, based on metallic iridium, is at most 0.05 mg. Ir / cm 2 , preferably less than 0.03 mg Ir / cm 2 and up to 0.01 mg Ir / cm 2 This means that with a small proportion of iridium oxide in relation to the total weight of the carrier material, manufacturability can be improved, whereby small amounts of iridium oxide are also advantageous for low manufacturing costs, since iridium is a very expensive precious metal.

[0025] In this context, it is further advantageous that the anode layer containing the hydrogen oxidation catalyst has a thickness, for example, of 0.5 to 2 µm. This provides a sufficiently large catalyst layer thickness, which is beneficial for good performance of the fuel cell MEA. In particular, a sufficiently large catalyst layer thickness prevents the anode from being flooded by water under cold and humid operating conditions. To prevent flooding, additional hydrophobic additives, such as perfluorinated polymers like PTFE, can be used in the anode if necessary.

[0026] Advantageously, the ceramic material is a metal oxide, and the metal is selected from the group consisting of titanium, niobium, tantalum, tungsten, silicon, zirconium, hafnium, tin, or mixtures or alloys thereof. The aforementioned metal oxides are characterized by good acid and corrosion resistance. Titanium oxide, niobium oxide, and tungsten oxide are particularly preferred. Furthermore, the ceramic material can be doped with other metals in small quantities. According to the present invention, the ceramic material does not necessarily have to be electrically conductive, since electrical conductivity is achieved through the use of iridium oxide. This also allows good electrical conductivity to be achieved in the anode, where particles of platinum and / or a platinum alloy are present on the substrate material, thereby enabling a high power density of the fuel cell MEA.

[0027] It is further advantageous that the hydrogen oxidation catalyst comprises particles of a platinum alloy, wherein one or more alloying metals are selected from the group consisting of ruthenium, rhodium, nickel, copper, and iridium. The aforementioned alloying metals are characterized by high corrosion stability and thus also improve the oxidation stability of the anode containing a platinum alloy.

[0028] In order to provide particularly high performance of the fuel cell MEA with very good cell reversal tolerance, the weight ratio of iridium in the support material to platinum in the anode is preferably less than or equal to 2:1, more preferably less than or equal to 1:1, further preferably less than or equal to 1:2 and particularly preferably less than or equal to 1:3, wherein the weight proportions that result in the weight ratio refer to the amounts of metallic iridium and metallic platinum.

[0029] In order to save costs, the basis weight of platinum in the anode (based on metallic Pt) is preferably at most 0.1 mg. Pt / cm 2 , preferably no more than 0.05 mg Pt / cm 2 and preferably no more than 0.03 mg Pt / cm 2 .

[0030] To improve the stability of the support material and prevent degradation, the support material preferably has a core-shell structure, with the ceramic material forming the core and the iridium oxide the shell. Furthermore, the iridium oxide can only partially cover the underlying ceramic material and form interconnected particle structures, thus creating electrically conductive channels within the layer. In the case of an anode layer, the electrical connection can also be achieved by platinum particles that connect the iridium-covered surfaces.

[0031] For reasons of chemical inertness and hydrophobic properties, the polymeric binder of the barrier layer is preferably selected from fluorinated polymers, and is in particular polytetrafluoroethylene. Alternatively, an ion-conducting polymeric binder can also be used in the barrier layer. In this case, the binder offers the advantage of promoting the OER reaction by providing water near the iridium oxide. For example, a PFSA binder of the same or a similar type as that used in the anode can be employed. In contrast to the anode, the barrier layer must be essentially free of platinum, particularly near or at the interface with a gas diffusion layer. This prevents carbon corrosion of the gas diffusion layer during cell inversion and thus ensures high cell inversion tolerance of the MEA.

[0032] The combination of a small amount of iridium oxide in the anode and / or the barrier layer of less than 0.05 mg Ir / cm 2 , preferably of less than 0.03 mg Ir / cm 2 and up to 0.01 mg Ir / cm 2The high proportion of ceramic material, combined with the high stability of the iridium oxide, makes this possible. Furthermore, it offers the advantage that only a very small amount of iridium oxide dissolves in the anode and / or barrier layer during anode potential cycles between low and high potentials and in the presence of hydrogen. This prevents contamination of the MEA by iridium oxide dissolution. In particular, no iridium in ionic form can migrate to the cathode and thus reduce the MEA's performance. Moreover, especially with the aforementioned small amounts of iridium, it is crucial that the iridium exhibits high stability against dissolution. Otherwise, the iridium will dissolve rapidly on the anode during cycles, and the cell reversal tolerance will be quickly lost.

[0033] The support material is obtained in particular by precipitation or deposition of an iridium precursor material onto the ceramic material (conventional production) and subsequent calcination in air or an oxygen source at temperatures above 400 °C, preferably above 450 °C and more preferably above 500 °C. The temperature should not exceed 1000 °C and preferably be less than 750 °C and more preferably less than 650 °C in order to avoid excessive aggregation and a loss of specific surface area.

[0034] A fuel cell comprising a fuel cell membrane electrode arrangement as disclosed above is also described according to the invention. Due to the use of the fuel cell membrane electrode arrangement according to the invention for the fuel cell according to the invention, the fuel cell is also characterized by high power density, high long-term stability, simple and reliable manufacturability, and, furthermore, by high cell reversal tolerance.

[0035] Further details, advantages and features of the present invention will become apparent from the following description of exemplary embodiments with reference to the drawing. It shows: Fig. 1 a fuel cell MEA according to a first embodiment in section, Fig. 2 a carrier material of the fuel cell MEA made of Fig. 1 and Fig. 3 a fuel cell MEA according to a second embodiment in section.

[0036] The figures depict only the essential details of the invention. All other details have been omitted for the sake of clarity.

[0037] Fig. Figure 1 shows in detail a fuel cell MEA 1 with a cathode 2, an anode 4 and an intermediate membrane 3. The membrane 3 is proton-conducting. The anode 4 comprises a support material 5 which is homogeneously distributed in an ionomer 14.

[0038] The carrier material 5 is described in detail in Fig. Figure 2 illustrates this. The support material 5 is in particulate form and comprises a ceramic material 6, which is in particular a metal oxide, wherein the metal is selected from the group consisting of titanium, niobium, tantalum, tungsten, silicon, zirconium, hafnium, tin, or mixtures or alloys thereof. The ceramic material is characterized by high chemical resistance, especially under acidic conditions. It is chemically inert, i.e., it has no influence on the reactions in the fuel cell MEA 1, and is not necessarily electrically conductive.

[0039] Iridium oxide particles 8 are deposited on the surface 7 of the ceramic material 6. The ceramic material 5 and the iridium oxide particles 8 form the support material. Based on the total weight of the support material 5, the weight fraction of iridium oxide 8 (this value refers to the proportion of metallic iridium) is at most 50 wt.%, preferably at most 35 wt.%, and particularly preferably at most 25 wt.%. The iridium oxide particles 8 are characterized by good electrical conductivity, which is important for the performance and cell reversal tolerance of the fuel cell MEA 1.In particular, a high cell reversal tolerance is achieved in the fuel cell MEA 1 by eliminating carbon materials in the anode and by using iridium oxide 8 as an oxygen evolution catalyst, which oxidizes water to oxygen, thus limiting the potential of the anode in the event of fuel depletion and reducing anode stress.

[0040] Due to the good electrical conductivity of the iridium oxide particle 8, conventional electrically conductive additives, such as carbon-containing materials like carbon black and graphite, can be omitted. The anode 4 therefore contains no carbon material. In other words, no carbon-containing material is added to the anode 4. The support material 5 is characterized by high corrosion resistance, so that no degradation by oxidative processes occurs during the operation of the fuel cell. This also results in high long-term stability with very good cell reversal tolerance.

[0041] In the Fig. 1 and Fig. In the embodiment of the fuel cell MEA 1 shown in Figure 2, the support material 5 is located in the anode 4. The anode 4 also comprises at least one ionomer 14 and a hydrogen oxidation catalyst 9, wherein the hydrogen oxidation catalyst 9 comprises particles of platinum and / or a platinum alloy, which are arranged, for example, on the support material 5. Particularly suitable alloying metals are selected from the group consisting of ruthenium, rhodium, nickel, copper, and iridium.

[0042] The basis weight of platinum (based on metallic platinum) in anode 4 is, in particular, at most 0.1 mg. Pt / cm 2 , preferably no more than 0.05 mg Pt / cm 2 and preferably no more than 0.03 mg Pt / cm 2 Even with these small amounts of platinum, a very good power density can be achieved for the fuel cell MEA 1.

[0043] Preferably, the weight ratio of iridium oxide 8 in the support material 5 to platinum in the anode 4 (in each case based on metallic iridium and metallic platinum) is less than or equal to 2:1, more preferably less than or equal to 1:1, more preferably less than or equal to 1:2 and particularly preferably less than or equal to 1:3.

[0044] The fuel cell MEA 1 described above is characterized by high cell reversal tolerance, high power density, high long-term stability, and simple and reliable manufacturability.

[0045] Fig. Figure 3 shows a fuel cell MEA 10 according to a second embodiment. The fuel cell MEA 10 again comprises a cathode 2, a membrane 3, and an anode 4. In addition, a barrier layer 11 and a gas diffusion layer 12 are also present.

[0046] In this embodiment, the anode 4 does not contain a support material (but may contain one, for example, shaped like the support material described above), but again includes an ionomer 14 and a hydrogen oxidation catalyst 9 comprising particles of platinum and / or a platinum alloy. Particularly suitable alloying metals are selected from the group consisting of ruthenium, rhodium, nickel, copper, and iridium.

[0047] The basis weight of platinum in anode 4 is at most 0.1 mg. Pt / cm 2 , preferably no more than 0.05 mg Pt / cm 2 and preferably no more than 0.03 mg Pt / cm 2 . These small amounts of platinum also allow for a very good power density to be achieved in the MEA 10 fuel cell.

[0048] To improve the cell reversal tolerance of the fuel cell MEA 10, a barrier layer 11 is provided, which is arranged on the anode side of the fuel cell MEA 10 between the anode 4 and the gas diffusion layer 12. The barrier layer 11 comprises a carrier material 5 and further at least one polymeric binder 13, which advantageously contains PTFE.

[0049] The carrier material 5 can be used like the carrier material made of Fig. 2, but without the hydrogen oxidation catalyst 9. Thus, the support material 5 is particulate and comprises a particulate ceramic material 6, on whose surface 7 particles of iridium oxide 8 are arranged. The areal weight of iridium oxide 8 (this value refers to the metallic iridium) in the barrier layer 11 is at most 0.05 mg. Ir / cm 2 and preferably less than 0.03 mg Ir / cm 2 .

[0050] In the fuel cell MEA 10, a very good cell reversal tolerance can also be achieved by using the carrier material 5 in the barrier layer 11.

[0051] In addition to the foregoing written description of the invention, explicit reference is hereby made to the graphic representation of the invention in the following for its supplementary disclosure. Fig. 1 to Fig. 3. Referenced. Reference symbol list 1 Fuel cell MEA 2 Cathode 3 Membran 4 Anode 5 Carrier material 6 ceramic material 7 Surface of the ceramic material 8 Iridium oxide 9 Hydrogen oxidation catalyst 10 Fuel Cell MEAs 11 Barrier layer 12 Gas diffusion layer 13 polymeric binder 14 lonomer QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] US 7677330 A

[0004]

Claims

[1] Fuel cell membrane electrode arrangement (1, 10) comprising: - a support material (5) comprising a ceramic material (6) and iridium oxide (8), wherein - the weight fraction of iridium oxide (8), based on metallic iridium, in relation to the total weight of the support material (5), is at most 50 wt.%, and wherein - the support material exhibits a weight loss of less than 3 wt.%, based on the weight fraction of the iridium oxide (8) when the support material is exposed for 12 hours at a temperature of 80 °C to a 3.3 vol.% hydrogen stream in argon. [2] Fuel cell membrane electrode arrangement (1, 10) according to claim 1, wherein the support material (5) is present in an anode (4) of the fuel cell membrane electrode arrangement (1) and the anode (4) further comprises at least one ionomer (14) and a hydrogen oxidation catalyst (9), wherein the hydrogen oxidation catalyst (9) comprises particles of platinum and / or a platinum alloy arranged on the support material (5). and / or wherein the carrier material (5) is located in a barrier layer (11) which is arranged between an anode (4) and a gas diffusion layer (12) of the fuel cell membrane electrode arrangement (10), wherein the barrier layer (11) further comprises at least one polymeric binder (13). [3] Fuel cell membrane electrode arrangement (1, 10) according to claim 1 or 2, wherein the iridium oxide (8) is in mixture or alloy with other metal oxides and / or wherein the weight fraction of iridium oxide (8), based on metallic iridium, in relation to the total weight of the support material (5), is at most 35 wt.%, and more preferably at most 25 wt.%. [4] Fuel cell membrane electrode arrangement (1, 10) according to claim 2 or 3, wherein the basis weight of iridium oxide (8), based on metallic iridium, in the barrier layer and / or the anode (11) is at most 0.05 mg Ir / cm 2 and preferably less than 0.03 mg Ir / cm 2 amounts. [5] Fuel cell membrane electrode arrangement (1, 10) according to one of the preceding claims, wherein the ceramic material (6) is a metal oxide and the metal is selected from the group consisting of titanium, niobium, tantalum, tungsten, silicon, zirconium, hafnium, tin or mixtures or alloys thereof. [6] Fuel cell membrane electrode arrangement (1, 10) according to one of claims 2 to 5, wherein the hydrogen oxidation catalyst (9) comprises particles of a platinum alloy, wherein one or more alloy metals are selected from the group consisting of ruthenium, rhodium, nickel, copper and iridium. [7] Fuel cell membrane electrode arrangement (1, 10) according to one of the preceding claims, wherein the weight ratio of iridium oxide (8) in the support material (5) to platinum in the anode, respectively based on metallic iridium and metallic platinum, is less than or equal to 2:1, preferably less than or equal to 1:1, more preferably less than or equal to 1:2 and particularly preferably less than or equal to 1:

3. [8] Fuel cell membrane electrode arrangement (1, 10) according to one of the preceding claims, wherein the basis weight of platinum in the anode is at most 0.1 mg Pt / cm 2 , preferably no more than 0.05 mg Pt / cm 2 and preferably no more than 0.03 mg Pt / cm 2 is and / or wherein the carrier material (5) has a core-shell structure. [9] Fuel cell membrane electrode arrangement (1, 10) according to any one of claims 2 to 8, wherein the polymeric binder (13) is selected from fluorinated polymers and in particular is polytetrafluoroethylene and / or wherein the anode (4) and / or the barrier layer (11) are free of carbon and carbon-containing compounds. [10] Fuel cell comprising a fuel cell membrane electrode arrangement (1, 10) according to any one of the preceding claims.

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