Membrane electrode component for fuel cells with improved durability and polymer electrolyte membrane fuel cell, which includes this

Abstract

Membrane electrode component for fuel cells, comprising: an electrolyte membrane; and one or more electrodes that are associated with the electrolyte membrane; in which at least the electrolyte membrane includes an antioxidant, and the antioxidant comprises a samarium (Sm)-doped cerium oxide (SDC), wherein the electrolyte membrane comprises a perfluorinated sulfonic acid-based ionomer and the antioxidant, wherein the electrolyte membrane comprises the antioxidant in an amount of 0.05 wt.% to 20 wt.%, based on the total weight of the perfluorinated sulfonic acid-based ionomer.

Description

TECHNICAL AREA

[0001] The present invention relates to a membrane electrode component for fuel cells with improved durability as well as a polymer electrolyte membrane fuel cell comprising it. BACKGROUND

[0002] Polymer electrolyte membrane fuel cells for vehicles are devices that generate electricity through an electrochemical reaction between hydrogen and oxygen in the air. They are widely recognized as next-generation, environmentally friendly energy sources that boast high electricity-generating efficiency and produce virtually no emissions other than water. Furthermore, polymer electrolyte membrane fuel cells generally operate at temperatures of 95°C or lower and possess a high energy density.

[0003] The reaction for electricity production in fuel cells takes place in a membrane electrode assembly (MEA), which comprises a membrane based on a perfluorinated sulfonic acid ionomer and a pair of electrodes, such as an anode and a cathode. Hydrogen supplied to the anode, which is an oxidation electrode for fuel cells, is split into a proton and an electron. The proton then moves across the membrane to a reduction electrode, i.e., the cathode. As a consequence, the electron is moved via an external circuit to the cathode. At the cathode, an oxygen molecule, the proton, and the electron then react to generate electricity and heat, with water (H₂O) being produced as a byproduct.

[0004] Generally, hydrogen and oxygen from the air, which are the reaction gases for fuel cells, pass through the electrolyte membrane to produce hydrogen peroxide (HOOH). The hydrogen peroxide produces oxygen-containing radicals, such as hydroxyl radicals (·OH) and hydroperoxyl radicals (·OOH). These radicals attack the perfluorinated sulfonic acid-based electrolyte membrane, including chemical degradation of the membrane, which ultimately reduces the lifespan of the fuel cell.

[0005] As a conventional technology to mitigate such chemical degradation of the electrolyte membrane, various types of antioxidants have been added to the electrolyte membrane.

[0006] For example, an antioxidant includes a primary antioxidant that acts as a radical scavenger, a secondary antioxidant that acts as a hydrogen peroxide decomposer, or the like.

[0007] Examples of primary antioxidants include cerium-based antioxidants, such as cerium oxide and cerium(III) nitrate hexahydrate antioxidants, terephthalate-based antioxidants, and the like. Secondary antioxidants include manganese-based antioxidants, such as manganese oxide antioxidants.

[0008] However, as described in the prior art, cerium oxide can lead to the problem that antioxidant activity is inversely proportional to long-term stability. Therefore, there is an urgent need for research into new antioxidants with both improved antioxidant activity and outstanding long-term stability.

[0009] US 2010 / 0167169 A1 discloses a sulfur-tolerant anode current collector material comprising a fabric or foam containing a cermet. The cermet consists of a metallic and a ceramic component. The metallic component comprises nickel, a nickel-cobalt alloy, or a mixture of a nickel compound and a cobalt compound. The ceramic component contains a mixed-conducting electrolyte material.

[0010] US 2014 / 0335440 A1 discloses a molded part made of a polymer electrolyte composition comprising a block copolymer with one or more hydrophilic segments (A1) containing an ionic group and a hydrophobic segment (A2) not containing an ionic group; and an additive, wherein the molded part forms a cocontinuous or lamellar phase separation structure and the additive is hydrophilic. SUMMARY OF THE REVELATION

[0011] In preferred aspects, the present invention provides a membrane electrode component that exhibits greatly improved durability by incorporating a novel antioxidant that possesses outstanding antioxidant activity and superior long-term stability.

[0012] The objects of the present invention are not limited to those described above. The objects of the present invention will become clear from the following description and could be implemented by means defined in the claims as well as by a combination thereof.

[0013] In one aspect, the present invention provides a membrane electrode assembly for fuel cells with improved durability. The membrane electrode assembly comprises an electrolyte membrane and one or more electrodes associated with the electrolyte membrane. For example, a pair of electrodes can be arranged on both or opposite surfaces of the electrolyte membrane. The phrase "associated with the electrolyte membrane," as used here, means that the electrolyte is used during the operation of the electrode. The electrolyte membrane comprises an antioxidant, and the antioxidant comprises a samarium (Sm)-doped cerium oxide.

[0014] The term "sarmarium(Sm)-doped cerium oxide," as used here, refers to cerium oxide containing one or more samarium ions that replace or substitute cerium ions. For example, samarium(III) ions (Sm) can be used to form cerium oxide. 3+) replace some of the cerium(IV) ions in cerium oxide (CeO2) so that the samarium(III) ions (Sm 3+ ) replace the cerium(IV) ions in a lattice structure of CeO2. The proportion of samarium(III) ions (Sm 3+ ) can suitably represent 0.1%, 1%, 3%, 5%, 10%, 20%, 30%, 40%, 40%, 50%, 60%, 70%, 80% or 90% of the total number of metal ions (e.g., the total number of Cer(IV) ions in undoped CeO2) that can be accommodated in CeO2.

[0015] The SDC can be represented by the following formula 1: SmxCe1−xO2−δ, where x 0 <x≤0,5 ist und δ ein Sauerstoff-Vakanzwert ist, der die Verbindung der Formel 1 elektrisch neutral macht.

[0016] The SDC may have been thermally treated at a temperature of 100°C to 1,000°C.

[0017] The SDC may have been thermally treated for 10 minutes to 10 hours.

[0018] The SDC can exhibit main diffraction peaks at 20 of 28±1.0°, 32±1.0°, 47±1.0° and 56±1.0° in an X-ray diffraction spectrum.

[0019] The SDC can suitably have a crystallite size of 5.5 nm to 60 nm.

[0020] The SDC can suitably have a BET surface area of ​​10 m². 2 / g up to 190 m 2 exhibit / g.

[0021] The electrolyte membrane comprises a perfluorinated sulfonic acid-based ionomer, a reinforcing layer to improve the mechanical strength of the electrolyte membrane, and the antioxidant. The electrolyte membrane contains the antioxidant in an amount of 0.05 wt% to 20 wt%, based on the total weight of the perfluorinated sulfonic acid-based ionomer.

[0022] In another aspect, the present invention provides a polymer electrolyte membrane fuel cell comprising the membrane electrode component described herein.

[0023] Furthermore, a vehicle is provided that includes the polymer electrolyte membrane fuel cell, which includes the membrane electrode component described herein.

[0024] In another aspect, the present invention provides a method for manufacturing a membrane electrode assembly. The method comprises heat-treating a samarium (Sm)-doped cerium oxide (SDC); feeding the heat-treated SDC to enclose at least one electrolyte membrane; and arranging a pair of electrodes on both surfaces of the electrolyte membrane, wherein the electrolyte membrane comprises a perfluorinated sulfonic acid-based ionomer and the antioxidant, and wherein the electrolyte membrane comprises the antioxidant in an amount of 0.05 wt.% to 20 wt.%, based on the total weight of the perfluorinated sulfonic acid-based ionomer.

[0025] The SDC can be appropriately represented by the following formula 1: SmxCe1−xO2−δ, where x 0 <x≤0,5 ist und δ einen Sauerstoff-Vakanzwert bereitstellt, der die Verbindung der Formel 1 elektrisch neutral macht.

[0026] The SDC may have been heat-treated at a temperature of 100°C to 1,000°C.

[0027] The SDC may have been heat-treated for 10 minutes to 10 hours.

[0028] The SDC can exhibit main diffraction peaks at 20 of 28±1.0°, 32±1.0°, 47±1.0° and 56±1.0° in an X-ray diffraction spectrum.

[0029] SDC can have a crystallite size of 5.5 nm to 60 nm. SDC can have a BET surface area of ​​10 m². 2 / g up to 190 m 2 exhibit / g.

[0030] The electrolyte membrane comprises a perfluorinated sulfonic acid-based ionomer and the antioxidant. The electrolyte membrane contains the antioxidant in an amount of 0.05 wt% to 20 wt%, based on the total weight of the perfluorinated sulfonic acid-based ionomer.

[0031] Other aspects and preferred embodiments of the invention are discussed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The foregoing and other features of the present invention will now be described in detail with reference to certain exemplary embodiments thereof, which are illustrated in the accompanying drawings, which are shown below for illustrative purposes only and thus do not limit the present invention, and wherein: Fig. 1 shows an exemplary membrane electrode component according to an exemplary embodiment of the present invention; Fig. 2 shows the X-ray diffraction (XRD) analysis results relating to an exemplary antioxidant (samarium (Sm)-doped cerium oxide) according to an exemplary embodiment of the present invention; Fig. 3 shows the measurement results of the BET surface with respect to an exemplary antioxidant (samarium(Sm)-doped cerium oxide) according to an exemplary embodiment of the present invention; Fig. 4 shows the test results of the antioxidant activity with respect to an exemplary antioxidant (samarium(Sm)-doped cerium oxide) according to an exemplary embodiment of the present invention by a methyl violet method; Fig. 5 shows the test results of the antioxidant activity with respect to an exemplary antioxidant (samarium (Sm)-doped cerium oxide) according to an exemplary embodiment of the present invention by UV-Vis spectroscopy; and Fig.6 shows the test results of the long-term stability of an exemplary antioxidant (samarium(Sm)-doped cerium oxide) according to an exemplary embodiment of the present invention by a dissolution test. DETAILED DESCRIPTION

[0033] The tasks described above, as well as other tasks, features and advantages, will become clearly understandable from the following preferred embodiments with reference to the accompanying drawings.

[0034] In the description of the figures, similar reference numerals denote similar elements. In the drawings, the sizes of the structures are exaggerated for clarity. It should be understood that although the terms first, second, etc., may be used herein to describe different elements, these elements are not to be limited by these terms, and they are used only to distinguish one element from another. For example, within the scope defined by the present invention, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element. The singular forms are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0035] It is further understood that the terms "comprise," "exhibit," and the like, when used in this description, specify the presence of the indicated features, numbers, steps, actions, elements, components, or combinations thereof, but do not exclude the presence or addition of one or more other features, numbers, steps, actions, elements, components, or combinations thereof. It is also understood that when an element such as a layer, film, area, or substrate is described as being "on" another element, it may be directly on top of the other element or it may be an intermediate element. It is also understood that when an element such as a layer, film, area, or substrate is described as being "under" another element, it may be directly beneath the other element or it may be an intermediate element.

[0036] Unless the context clearly indicates otherwise, all numbers, values, and / or expressions representing ingredients, reaction conditions, polymer compositions, and quantities of mixtures used in this description are approximations that reflect various measurement uncertainties inherent in obtaining these values, among other things. Furthermore, where numerical ranges are disclosed in the description, these ranges are continuous and include all numbers from the minimum to the maximum, including the maximum, within the range, unless otherwise defined. If the range is denoted by integers, it further includes all integers from the minimum to the maximum, including the maximum, within the range, unless otherwise defined.Unless specifically stated or evident from the context, as used here, the terms denoting ingredients, reaction conditions, polymer compositions and quantities of mixtures used in the description are approximations reflecting various values, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.05% or 0.01% of the stated value.

[0037] It should be understood that when a range is described in terms of a parameter, the parameter includes all values, including endpoints, disclosed within the range. For example, the range "5 to 10" includes the values ​​5, 6, 7, 8, 9, and 10, as well as arbitrary subranges, such as ranges from 6 to 10, 7 to 10, 6 to 9, and 7 to 9, and any values, such as 5.5, 6.5, 7.5, 5.5 to 8.5, and 6.5 to 9, between suitable integers that fall within the range. Additionally, for example, the range of "10% to 30%" includes all integers containing values ​​such as 10%, 11%, 12% and 13% as well as 30%, and any subranges of 10% to 15%, 12% to 18% or 20% to 30%, as well as any values ​​such as 10.5%, 15.5% and 25.5% between suitable integers that lie within the range.

[0038] It should be understood that the term "vehicle" or "vehicle-" or other similar expressions as used herein include motor vehicles in general, such as passenger cars, including sports utility vehicles (SUVs), buses, trucks, various commercial motor vehicles, watercraft, including a variety of boats and ships, aircraft and the like, and hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles or vehicles powered by other alternative fuels (e.g., fuels derived from sources other than petroleum). As defined herein, a hybrid vehicle is a vehicle that has two or more sources of propulsion, e.g., vehicles powered by both gasoline and electric current.

[0039] Fig.Figure 1 schematically illustrates an exemplary membrane electrode component according to an exemplary embodiment of the present invention. As shown in Fig. As shown in Figure 1, the membrane electrode assembly comprises an electrolyte membrane (10) and a pair of electrodes (20) arranged on both surfaces of the electrolyte membrane. Here, “a pair of electrodes” refers to an anode and a cathode located on opposite surfaces or sides of the electrolyte membrane.

[0040] At least the electrolyte membrane (10) contains an antioxidant.

[0041] The electrolyte membrane (10) comprises a perfluorinated sulfonic acid-based ionomer, a reinforcing layer to improve the mechanical strength of the electrolyte membrane, and the antioxidant. The electrolyte membrane (10) contains the antioxidant in an amount of 0.05 wt% to 20 wt%, based on the total weight of the perfluorinated sulfonic acid-based ionomer. If the antioxidant content is less than 0.05 wt%, the chemical stability of the electrolyte membrane may not be maintained due to excessively low antioxidant activity, and if the content is greater than 20 wt%, the proton conductivity of the electrolyte membrane may be reduced and its brittleness may be increased.

[0042] The antioxidant is an Sm-doped cerium oxide (hereinafter referred to as "SDC"). The SDC can be a compound containing samarium(III) ions (Sm 3+) contains compounds that replace some of the cerium(IV) ions in cerium oxide (CeO2) with a fluorite structure. As a result, the oxygen vacancy can be increased and the redox reaction properties of the cerium ions can be improved.

[0043] The antioxidant can be represented by the following formula 1. SmxCe1−xO2−δ, where x 0 <x≤0,5 ist und δ einen Sauerstoff-Vakanzwert bereitstellt, der die Verbindung der Formel 1 elektrisch neutral macht, z.B. 0<δ≤0,25.

[0044] If x is greater than 0.5, the inherent structural properties of cerium oxide may be degraded. For this reason, x is preferably located within this range.

[0045] As mentioned above, antioxidant activity can be increased, but long-term stability may be impaired if the antioxidant crystal size decreases. The present inventors have realized that by controlling the crystallite size and surface area of ​​the SDC through thermal treatment of the SDC at a high temperature, both superior antioxidant activity and outstanding long-term stability can be ensured.

[0046] The antioxidant can preferably be SDC, which has been thermally treated at a temperature of 100°C to 1,000°C for 10 minutes to 10 hours.

[0047] If the temperature of the thermal treatment is less than 100°C, the effect of the thermal treatment may be insufficient, and the antioxidant activity of the SDC may be increased, while its long-term stability may be reduced. If the temperature is greater than 1,000°C, the effect of the thermal treatment may be excessive, and the long-term stability of the SDC may be increased, but its antioxidant activity may be reduced.

[0048] If the time for thermal treatment is less than 10 minutes, the effect of the thermal treatment is insufficient, the antioxidant activity of the SDC is high, but the long-term stability is low, and if the time is longer than 10 hours, the time for the process cycle becomes excessively long.

[0049] The thermal treatment of SDC can be carried out in an atmospheric environment. EXAMPLE

[0050] The antioxidant according to the invention is described in more detail below with reference to the following examples. Production of the antioxidant

[0051] An antioxidant was produced according to the conditions shown in Table 1 below. TABLE 1 Object composition Thermal treatment temperature [°C] Thermal treatment time [hours] Example 1 (SDC-400) Sm 0.2 Ce 0.8 O 2-δ ,δ provides an oxygen vacancy value that makes the compound of formula 1 electrically neutral 400 2 Example 2 (SDC-600) 600 2 Example 3 (SDC-800) 800 2 Example 4 (SDC-1000) 1.000 2 Comparison example 1 (SDC-NA) no thermal treatment no thermal treatment Comparison example 2 (SDC-1100) 1.100 2

[0052] The antioxidants according to examples 1 to 4 and comparison examples 1 and 2 were subjected to microstructure analysis, antioxidant activity testing, and long-term stability testing. Microstructure analysis 1) X-ray diffraction (XRD) analysis

[0053] The changes in crystal size of the antioxidants in examples 1 to 4 and comparison examples 1 and 2 were measured by X-ray diffraction. The results are presented in Fig. 2 shown.

[0054] As in Fig.As shown in Figure 2, examples 1 to 4 and comparison example 2, which were thermally treated at a high temperature, exhibited a gradual, observable growth in the characteristic crystal peaks compared to comparison example 1. Specifically, the main diffraction peaks with high intensities are shown in the X-ray diffraction spectrum at 20° = 28 ± 1.0°, 32 ± 1.0°, 47 ± 1.0°, and 56 ± 1.0°. 2) Calculation of crystal size

[0055] The crystallite sizes of the antioxidants in Examples 1 to 4 and in Comparison Examples 1 and 2 were calculated using the Debye-Scherrer equation. The results are shown in Table 2 below. TABLE 2 Object Crystallite size [nm] Example 1 (SDC-400) 6,8 Example 2 (SDC-600) 13,3 Example 3 (SDC-800) 22,4 Example 4 (SDC-1000) 43,8 Comparison example 1 (SDC-NA) 5,1 Comparison example 2 (SDC-1100) 365,8

[0056] As shown in Table 2, the crystallite size of the SDC gradually increased with increasing thermal treatment temperature. However, when the thermal treatment temperature reached 1100°C, the crystallite size of the SDC rapidly increased to 365.8 nm, which is excessively large. 3) Measurement of the BET (Brunauer-Emmett-Teller) surface area

[0057] The BET surface areas of the antioxidants in examples 1 to 4 and comparison examples 1 and 2 were measured using a surface analysis machine (TriStar II, Micromeritics Co., USA). The results are presented in the Fig. 3 shown.

[0058] Taking into account the results of comparative example 1, examples 1 to 4 and comparative example 2, which are presented in Fig. As shown in Figure 3, the BET surface area of ​​the antioxidant decreases when thermal treatment is performed at high temperature.

[0059] In other words, the antioxidant in comparison example 1 had a BET surface area of ​​199.2 m². 2 / g, the antioxidants of examples 1 to 4, which had been thermally treated at a temperature of 400°C, 600°C, 800°C and 1000°C respectively, showed a gradually reduced BET surface area of ​​157.0 m² 2 / g, 68.2 m 2 / g, 36.1 m 2 / g or 17.1 m 2 / g, and the antioxidant of comparison example 2, which had been thermally treated at a temperature of 1,100°C, had a considerably smaller BET surface area of ​​1.8 m² 2 / g on. Antioxidant activity test1) Antioxidant activity test using a methyl violet method

[0060] A methyl violet method was used, which allows rapid verification by the naked eye, to test the antioxidant activities of the antioxidants of Examples 1 to 4 and of the comparison examples 1 and 2.

[0061] Methyl violet was produced with iron(II) sulfate heptahydrate (FeSO₄) 4· 7H2O), hydrogen peroxide, an antioxidant and the like, and the color change was observed.

[0062] When the antioxidant activity of the antioxidant increases, the original color of the methyl violet is well maintained, and when the antioxidant activity decreases, the violet becomes pale and eventually colorless.

[0063] Methyl violet, iron(II) sulfate heptahydrate, and hydrogen peroxide were mixed in a weight ratio of 30:1:1 to prepare a methyl violet test solution, and the antioxidants from Examples 1 to 4 and Comparison Examples 1 and 2 were each added to the solution in amounts of 10 mg. The results are presented in Fig. 4 shown.

[0064] As in Fig.As shown in Figure 4, the violet color of methyl violet gradually faded in both Comparison Example 1 and Comparison Example 2. Specifically, Examples 1 to 4 retained their vibrant violet color, although some of it also faded, whereas the solution color of Comparison Example 2 rapidly became colorless. This indicates that Examples 1 to 4 retained good antioxidant activity, whereas Comparison Example 2 exhibited considerably reduced antioxidant activity. 2) Testing of antioxidant activity by UV-Vis spectroscopy

[0065] The absorbance of a methyl violet test solution was measured and compared to more accurately test the antioxidant activity.

[0066] When the antioxidant activity of the antioxidant is excellent, a high absorption intensity appears at 582 nm, which is the inherent absorption wavelength of methyl violet, whereas when the antioxidant activity is low, a low absorption intensity appears.

[0067] The absorbances of the methyl violet solutions according to Examples 1 to 4 and Comparative Examples 1 and 2 were measured using a UV-Vis spectrometer (UV-3600, Shimadzu Corporation, Japan). The results are presented in Fig. 5 shown.

[0068] As in Fig.As shown in Figure 5, the UV absorption intensity gradually decreases from comparison example 1 to comparison example 2. In other words, comparison example 1 maintained a high absorption intensity at a wavelength of 582 nm, whereas examples 1 to 4 exhibited a partially reduced absorption intensity, but still showed considerable absorption intensity and good antioxidant activity. On the other hand, comparison example 2 showed a rapidly decreasing absorption intensity and a considerable reduction in antioxidant activity. Long-term stability test1) Long-term stability test by a dissolution test

[0069] To test the long-term stability of the antioxidants according to Examples 1 to 4 and Comparative Examples 1 and 2, the antioxidants were subjected to a dissolution test under acidic conditions simulating the actual operating conditions of a polymer electrolyte membrane for fuel cells. First, the antioxidant was dispersed and dissolved in 12 M sulfuric acid (H₂SO₄) for 72 hours, and the absorption intensity of the solution was measured by UV-Vis spectroscopy to test the dissolution stability of the antioxidant.

[0070] If the dissolution resistance or stability of the antioxidant in sulfuric acid decreases, the amount of antioxidant dissolved in sulfuric acid increases, and its absorption intensity also increases. Conversely, if the dissolution resistance or stability increases, its absorption intensity decreases. Specifically, the long-term stability of the antioxidant can be determined by observing the change in absorption intensity at a wavelength of 320 nm, which is a characteristic value for Ce among the absorption wavelengths used in UV-Vis spectroscopy. 4+ -ions in the antioxidant.

[0071] To measure the absorption intensity, a solution of the antioxidant in sulfuric acid was diluted in deionized water at a ratio of 1:9 (vol.% / vol.%). The results are presented in Fig. 6 shown.

[0072] As in Fig.As shown in Figure 6, comparative example 1 exhibited a considerably high absorption intensity and thus very poor long-term stability. However, in examples 1 to 4 and comparative example 2, the resistance to dissolution with sulfuric acid increased, as the UV-Vis absorption intensity gradually decreased. Antioxidant activity and long-term stability test

[0073] The results are shown and summarized in Table 3 below. TABLE 3 Object thermal treatment temperature [°C] Microstructure properties Antioxidant activity Long-term stability Crystallite size [nm] BET surface [m²] 2 / G] Comparative example 1 unheat-treated 5, 1 199,2 excellent bad Example 1 400 6,8 157,0 excellent good Example 2 600 13,3 68,2 excellent good Example 3 800 22,4 36,1 good excellent Example 4 1000 43,8 17,1 good excellent Comparative example 2 1100 365,8 1,8 bad excellent

[0074] As shown in Table 3 above, the crystallite size of the antioxidant ranged from 5.5 nm to 60 nm and the BET surface area of ​​this was 10 m². 2 / g up to 190 m 2 / g, to ensure both good antioxidant activity and long-term stability of the antioxidant. Therefore, the SDC represented by the following formula 1 should be thermally treated at a temperature of 100°C to 1,000°C for 10 minutes to 10 hours. SmxCe1−xO2−δ, where x 0 <x≤0,5 erfüllt und δ einen Sauerstoff-Vakanzwert bereitstellt, der die Verbindung der Formel 1 elektrisch neutral macht.

[0075] As can be seen from the foregoing, the present invention provides a new antioxidant with outstanding antioxidant activity and outstanding long-term stability, and a membrane electrode component in which the antioxidant is introduced can exhibit greatly improved durability.

Claims

[1] Membrane electrode assembly for fuel cells, comprising: an electrolyte membrane; and one or more electrodes that are associated with the electrolyte membrane; in which at least the electrolyte membrane includes an antioxidant, and the antioxidant comprises a samarium (Sm)-doped cerium oxide (SDC), wherein the electrolyte membrane comprises a perfluorinated sulfonic acid-based ionomer and the antioxidant, wherein the electrolyte membrane comprises the antioxidant in an amount of 0.05 wt.% to 20 wt.%, based on the total weight of the perfluorinated sulfonic acid-based ionomer. [2] Membrane electrode assembly according to claim 1, wherein a pair of electrodes are arranged on both surfaces of the electrolyte membrane. [3] Membrane electrode component according to claim 1, wherein the SDC is represented by the following formula 1: SmxCe1−xO2−δ, where x 0 <x≤0,5 ist und δ ein Sauerstoff-Vakanzwert darstellt, der die Verbindung der Formel 1 elektrisch neutral macht. [4] Membrane electrode component according to claim 1, wherein the SDC has been thermally treated at a temperature of 100°C to 1,000°C. [5] Membrane electrode component according to claim 4, wherein the SDC has been thermally treated for 10 minutes to 10 hours. [6] Membrane electrode component according to claim 1, wherein the SDC has main diffraction peaks at 2Θ of 28±1.0°, 32±1.0°, 47±1.0° and 56±1.0° in an X-ray diffraction spectrum. [7] Membrane electrode component according to claim 1, wherein the SDC has a crystallite size of 5.5 nm to 60 nm. [8] Membrane electrode component for fuel cells according to claim 1, wherein the SDC has a BET surface area of ​​10 m² 2 / g up to 190 m 2 / g [9] Polymer electrolyte membrane fuel cell comprising a membrane electrode assembly according to claim 1. [10] Vehicle comprising a polymer electrolyte membrane fuel cell according to claim 9. [11] Method for manufacturing a membrane electrode assembly, comprising: Heat treatment of a samarium(Sm)-doped cerium oxide (SDC); Feeding to enclose the heat-treated SDC to at least one electrolyte membrane; and Arranging a pair of electrodes on both surfaces of the electrolyte membrane, wherein the electrolyte membrane comprises a perfluorinated sulfonic acid-based ionomer and the antioxidant, wherein the electrolyte membrane comprises the antioxidant in an amount of 0.05 wt.% to 20 wt.%, based on the total weight of the perfluorinated sulfonic acid-based ionomer. [12] Method according to claim 11, wherein the SDC is represented by the following formula 1: SmxCe1−xO2−δ, where x 0 <x≤0,5 ist und δ ein Sauerstoff-Vakanzwert darstellt, der die Verbindung der Formel 1 elektrisch neutral macht. [13] Method according to claim 11, wherein the SDC is thermally treated at a temperature of 100°C to 1,000°C. [14] Method according to claim 13, wherein the SDC is thermally treated for 10 minutes to 10 hours. [15] Method according to claim 11, wherein the SDC has main diffraction peaks at 2Θ of 28±1.0°, 32±1.0°, 47±1.0° and 56±1.0° in an X-ray diffraction spectrum. [16] Method according to claim 11, wherein the SDC has a crystallite size of 5.5 nm to 60 nm. [17] Method according to claim 11, wherein the SDC has a BET surface area of ​​10 m² 2 / g up to 190 m 2 / g

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