KR20200043155A - Fuel cell electrode with organic compound having phosphonic acid group and manufacturing method thereof - Google Patents

Abstract

According to an embodiment of the present invention, provided are an electrode for a high-temperature polymeric fuel cell coated with an organic compound having a phosphonic acid group and a manufacturing method thereof. The electrode for a high-temperature polymeric fuel cell according to an embodiment of the present invention can improve the performance of a fuel cell by applying the organic compound having the phosphonic acid group to the electrode to provide high proton conductivity even in a high temperature environment. In addition, also provided are a membrane electrode assembly including the electrode for a high-temperature polymeric fuel cell, and a fuel cell.

Description

{Fuel cell electrode with organic compound having phosphonic acid group and manufacturing method thereof}

The present invention relates to a fuel cell electrode and a method for manufacturing the same, and more particularly, to a high temperature polymer fuel cell electrode and a method for manufacturing the same.

A polymer electrolyte fuel cell is a fuel cell that uses a polymer membrane having hydrogen ion exchange properties as an electrolyte, a solid polymer electrolyte fuel cell (SPEFC), a solid polymer fuel cell (SPFC), a polymer electrolyte fuel cell (PEFC), or a proton-exchange membrane. It is called by various names such as fuel cell (PEMFC). The polymer electrolyte fuel cell has advantages such as high efficiency, high current density and output density, simple design and easy manufacturing compared to the fuel cell of the type. Due to these characteristics, the polymer electrolyte fuel cell can be applied to a wide variety of fields, such as power sources for pollution-free vehicles, local installation power generation, spacecraft power, mobile power, and military power.

The polymer electrolyte fuel cell can be divided into a low temperature type and a high temperature type operated at 100 ° C or higher, and the high temperature polymer electrolyte fuel cell has several advantages over a low temperature type. For example, the high-temperature polymer electrolyte fuel cell does not require a humidifier, which is necessary in the existing low-temperature type, because the proton conduction mechanism does not depend on water, and various problems caused by condensate such as flooding that can occur in the low-temperature type It does not have the advantage of easy stack design. In addition, due to the high operating temperature, the electrochemical reaction of the fuel cell can be improved, and the mass transfer resistance is also reduced, so that concentration polarization can also be reduced. Research into developing a high-temperature polymer electrolyte fuel cell having various advantages as described above has been actively conducted.

Republic of Korea Registered Patent No. 10-1101497

Technical problem to be achieved by the present invention is to provide an electrode for a high-temperature polymer fuel cell coated with an organic compound having a phosphonic acid group. By applying the organic compound having the phosphonic acid group to the electrode, it is possible to provide high proton conductivity even in a high temperature environment, thus improving performance of a fuel cell manufactured using the same.

In addition, to provide a membrane electrode assembly comprising an electrode for a high-temperature polymer fuel cell coated with an organic compound having the phosphonic acid group.

In addition, to provide a high-temperature polymer fuel cell comprising an electrode for a high-temperature polymer fuel cell coated with the organic compound having the phosphonic acid group.

In addition, to provide a method for producing a high-temperature polymer fuel cell coated with an organic compound having a phosphonic acid group.

The technical problem to be achieved by the present invention is not limited to the technical problem mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary knowledge in the technical field to which the present invention belongs from the following description. There will be.

In order to achieve the above technical problem, an embodiment of the present invention can provide an electrode for a high-temperature polymer fuel cell. The high temperature polymer fuel cell electrode may include a gas diffusion layer, a catalyst layer formed on the gas diffusion layer, and an organic compound having a phosphonic acid group applied on the catalyst layer.

In addition, the organic compound having a phosphonic acid group is a single molecule having a phosphonic acid group; Monomer; Or it characterized in that it comprises a polymer compound having a phosphonic acid group in the main chain and / or side chains.

In addition, the organic compound having a phosphonic acid group is vinylphosphonic acid, isopropenylphosphonic acid, 1-phenylvinyl phosphonic acid, methylenephosphonic acid (N, N , N ', N'-ethylenediamine tetrakis), 1-Hydroxyethane-1,1-diphosphonic acid, alendronic acid, 2-aminoethylphos Characterized in that it comprises at least one compound selected from phosphonic acid (2-Aminoethylphosphonic acid), methylphosphonic acid (methylphosphonic acid) and p-hydroxyphenyl phosphonic acid (p-hydroxypheny phosphonic acid).

In addition, the thickness of the catalyst layer is characterized in that 5 μm to 120 μm.

In addition, the weight per unit area (M / A) of the organic compound having the phosphonic acid group applied on the catalyst layer is 0.1 mg / cm ² to 15 mg / cm ² .

In addition, the catalyst layer is polyvinylidene fluoride (polyvinylidene fluoride), polytetrafluoro ethylene (Polytetrafluoroethylene), tetrafluoroethylene-hexafluoroethylene copolymer, perfluoroethylene propylene copolymer and polyphenylene oxide-methyl It may include a binder formed of one or more compounds selected from the group consisting of phosphonic acid copolymers.

In addition, the catalyst layer may include a metal catalyst, wherein the metal catalyst can activate the oxidation reaction of hydrogen and the oxidation reaction of oxygen.

In addition, the catalyst layer is platinum; Palladium; Palladium alloy; Or a metal catalyst formed of an alloy of platinum and one or more metals selected from the group consisting of cobalt, gold, ruthenium, tin, molybdenum, palladium, rhodium, iridium, bismuth, copper, yttrium and chromium.

In addition, the electrode for the high-temperature polymer fuel cell exhibits peaks at 1620, 1240, 1070, 960 and 751 cm ^-1 when measured by FT-IR, and the error range of each peak is ± 5 cm ^-1 .

Another embodiment of the present invention can provide a membrane electrode assembly for a high-temperature polymer fuel cell. In this case, the membrane electrode assembly for a high-temperature polymer fuel cell may include an electrode for a high-temperature polymer fuel cell according to an embodiment of the present invention.

Another embodiment of the present invention can provide a high-temperature polymer fuel cell. In this case, the high-temperature polymer fuel cell may include an electrode for a high-temperature polymer fuel cell according to an embodiment of the present invention.

Another embodiment of the present invention can provide a method of manufacturing an electrode for a high-temperature polymer fuel cell. At this time, the method for manufacturing the electrode for a high-temperature polymer fuel cell may include preparing a composition containing an organic compound having a phosphonic acid group and applying the composition on the catalyst layer of the electrode for a fuel cell.

In addition, the electrode for the fuel cell, the step of preparing a binder solution by mixing a binder material in a solvent, adding a metal catalyst supported on a carbon support to the binder solution to prepare a binder-catalyst mixture solution and the mixed solution It may be prepared through the step of forming a catalyst layer by coating on the gas diffusion layer.

In addition, the organic compound having a phosphonic acid group is a single molecule having a phosphonic acid group; Monomer; Or it may include a polymer compound having a phosphonic acid group in the main chain and / or side chains.

In addition, the organic compound having a phosphonic acid group is vinyl phosphonic acid, isopropenyl phosphonic acid, 1-phenylvinyl phosphonic acid, methylenephosphonic acid (N , N, N ', N'-ethylenediamine tetrakis), 1-Hydroxyethane-1,1-diphosphonic acid, alendronic acid, 2-amino It may include at least one compound selected from ethyl phosphonic acid (2-Aminoethylphosphonic acid), methyl phosphonic acid (methylphosphonic acid) and p-hydroxyphenyl phosphonic acid (p-hydroxypheny phosphonic acid).

In addition, in the step of applying the composition to the electrode for a fuel cell, the weight per unit area (M / A) of the organic compound having the phosphonic acid group applied on the catalyst layer is 0.1 mg / cm ² to 15 mg / cm ² It is characterized by being.

According to an embodiment of the present invention, the performance of a fuel cell can be improved by applying an organic compound containing a phosphonic acid group to an electrode for a high-temperature polymer fuel cell. At this time, the organic compound containing the phosphonic acid group can be applied to the electrode to provide high proton conductivity even at high temperatures, and thus, higher voltage and power at the same current density and at the same catalyst content than when using only a conventional binder material. Can provide

It should be understood that the effects of the present invention are not limited to the above-described effects, and include all effects that can be deduced from the configuration of the invention described in the detailed description or claims of the present invention.

1 is a graph showing the results of P-31 NMR measurement of vinyl phosphonic acid present in an electrode for a high-temperature polymer fuel cell.
2 is a graph of measuring voltages according to the current density (A / cm ² ) of a fuel cell according to Preparation Examples 1 to 4 and Comparative Example 1.
3 is a graph showing normalized results of FIG. 2 according to the platinum (Pt) loading amount.
4 is a graph measuring voltage and power values according to current densities (A / cm ² ) of a fuel cell according to Preparation Examples 5 to 7 and Comparative Example ² .
Figure 5 (a) is a graph showing the FT-IR measurement results of the Cathode electrode according to Preparation Example 2.
Figure 5 (b) is a graph showing the results of FT-IR measurement of the Cathode electrode according to Preparation Example 6.

Hereinafter, the present invention will be described with reference to the accompanying drawings. However, the present invention may be implemented in various different forms, and thus is not limited to the embodiments described herein. In addition, in order to clearly describe the present invention in the drawings, parts irrelevant to the description are omitted, and like reference numerals are assigned to similar parts throughout the specification.

Throughout the specification, when a part is "connected (connected, contacted, coupled)" to another part, this is not only when it is "directly connected", but also "indirectly" with another member in between. "It also includes the case where it is. Also, when a part is said to “include” a certain component, this means that other components may be further provided instead of excluding the other component unless otherwise stated.

The terms used in this specification are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as “include” or “have” are intended to indicate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, and that one or more other features are present. It should be understood that the existence or addition possibilities of fields or numbers, steps, operations, components, parts or combinations thereof are not excluded in advance.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

An electrode for a high-temperature polymer fuel cell according to an embodiment of the present invention will be described.

The electrode for a high-temperature polymer fuel cell according to an embodiment of the present invention may include a gas diffusion layer, a catalyst layer formed on the gas diffusion layer, and an organic compound having a phosphonic acid group applied on the catalyst layer.

Conventional high-temperature polymer fuel cells operate at a high temperature of 100 ° C. or higher, and there is a problem that nafion cannot be used as an ionomer. Accordingly, a binder material having excellent thermal and mechanical stability is added as a support, and phosphoric acid is impregnated as a proton conductor.

The electrode for a high-temperature polymer fuel cell according to an embodiment of the present invention can provide a high proton conductivity even at high temperatures by applying an organic compound containing a phosphonic acid group on the catalyst layer. It is possible to provide a higher voltage at the same current density and the same catalyst content as compared to the case where only the existing binder material is used, thus improving the performance of the fuel cell.

The organic compound having a phosphonic acid group is a single molecule having a phosphonic acid group; Monomer; Or it may include a polymer compound having a phosphonic acid group in the main chain and / or side chains.

For example, the organic compound having a phosphonic acid group is vinyl phosphonic acid, isopropenyl phosphonic acid, 1-phenylvinyl phosphonic acid, methylenephosphonic acid (N, N, N ', N'-ethylenediamine tetrakis), 1-hydroxyethane-1,1-diphosphonic acid (1-Hydroxyethane-1,1-diphosphonic acid), alendronic acid, 2 -Aminoethyl phosphonic acid (2-Aminoethylphosphonic acid), methyl phosphonic acid (methylphosphonic acid) and p-hydroxyphenyl phosphonic acid (p-hydroxypheny phosphonic acid) may include one or more compounds selected from.

The weight per unit area (M / A) of the organic compound having the phosphonic acid group applied on the catalyst layer is 0.1 mg / cm ² to 15 mg / cm ² . When the weight per unit area (M / A) of the organic compound having a phosphonic acid group is less than 0.1 mg / cm ² , it is not preferable because it cannot sufficiently provide a proton conductivity improving effect. When the weight per unit area of the organic compound having the phosphonic acid group (M / A) is more than 15 mg / cm ² , the organic compound having the phosphonic acid group can screen the metal catalyst and lower the activity of the catalyst layer. Do not.

Since the catalyst layer contains an organic compound having a phosphonic acid group, an infrared (IR) spectrum corresponding to the phosphonic acid group can be obtained when FT-IR measurement of the electrode for the high-temperature polymer fuel cell is performed. For example, in the vicinity of 1620 cm ^-1 , 1240 cm ^-1 , 1070 cm ^-1 , 960 cm ^-1 , and 751 cm ^-1 , the stretching vibration of POH bond, the stretching vibration of P = O bond, and the stretching of PO bond, respectively. Peaks corresponding to vibration, stretching vibration of PO bond, and bending vibration of POH bond can be obtained, and the error range of each peak may be ± 5 cm ^-1 .

The catalyst layer may include a metal catalyst supported on a carbon support.

The metal catalyst can be used without limitation as long as it is suitable for activating the oxidation reaction of hydrogen and the reduction reaction of oxygen.

For example, the metal catalyst may include a metal catalyst formed of platinum (Pt), palladium (Pd), platinum (Pt) alloy or palladium (Pd) alloy, preferably platinum (Pt) or platinum (Pt) ) It may include a metal catalyst formed of an alloy.

At this time, the platinum (Pt) alloy is cobalt (Co), gold (Au), ruthenium (Ru), tin (Sn), molybdenum (Mo), palladium (Pd), rhodium (Rh), iridium (Ir) , Bismuth (Bi), copper (Cu), yttrium (Y) and chromium (Cr) may include a metal catalyst formed of an alloy of at least one metal and platinum (Pt) selected from the group consisting of.

The metal catalyst is not limited thereto, and it will be sufficient if it is used in a high temperature polymer fuel cell to improve performance. For example, the metal catalyst may be a metal material such as palladium, ruthenium, bismuth (Bi), tin (Sn) or molybdenum (Mo) deposited on platinum (Pt).

At this time, in order to increase the effective surface area of the metal catalyst, the metal catalyst may be used in a form supported on a carbon support.

For example, it may be used in the form of a Pt / C catalyst in which platinum (Pt) particles having a size of 1 to 5 nm are supported on the surface of fine carbon black particles having a size of 20 to 40 nm.

The catalyst layer may include a binder, and the binder may provide structural stability by fixing a metal catalyst supported on a carbon support.

In this case, the binder will be sufficient if it is chemically and mechanically stable in a fuel cell environment and there is no problem in mass transfer of hydrogen, oxygen, and water.

For example, the binder is polyvinylidene fluoride, polytetrafluoroethylene, tetrafluoroethylene-hexafluoroethylene copolymer, perfluoroethylene propylene copolymer and polyphenylene oxide -Methyl phosphonic acid copolymer may include a binder formed of at least one compound selected from the group consisting of.

The thickness of the catalyst layer of the electrode for a high-temperature polymer fuel cell according to an embodiment of the present invention is characterized in that it is 5 μm to 120 μm. When the thickness of the catalyst layer is less than 5 μm, mechanical stability of the electrode may deteriorate, which is not preferable. When the thickness of the catalyst layer is more than 120 μm, the proton conductivity decreases, which may degrade the performance of the fuel cell, which is undesirable.

A membrane electrode assembly for a high-temperature polymer fuel cell according to another embodiment of the present invention will be described.

The membrane electrode assembly for a high temperature polymer fuel cell according to another embodiment of the present invention may include an electrode for a high temperature polymer fuel cell according to an embodiment of the present invention.

A high temperature polymer fuel cell according to another embodiment of the present invention will be described.

The high temperature polymer fuel cell according to another embodiment of the present invention may include an electrode for a high temperature polymer fuel cell according to an embodiment of the present invention.

Next, a method of manufacturing an electrode for a high-temperature fuel cell according to another embodiment of the present invention will be described.

The manufacturing method of the electrode for a high-temperature polymer fuel cell may include preparing a composition containing an organic compound having a phosphonic acid group and applying the composition on the catalyst layer of the electrode for a fuel cell.

At this time, the electrode for the fuel cell, mixing a binder material in a solvent to prepare a binder solution, adding a metal catalyst supported on a carbon support to the binder solution to prepare a binder-catalyst mixed solution and the mixed solution It may be prepared through the step of forming a catalyst layer by coating on the gas diffusion layer.

At this time, the organic compound having a phosphonic acid group is a single molecule having a phosphonic acid group; Monomer; Or it may include a polymer compound having a phosphonic acid group in the main chain and / or side chains.

For example, the organic compound having a phosphonic acid group is vinyl phosphonic acid, isopropenyl phosphonic acid, 1-phenylvinyl phosphonic acid, methylenephosphonic acid (N, N, N ', N'-ethylenediamine tetrakis), 1-hydroxyethane-1,1-diphosphonic acid (1-Hydroxyethane-1,1-diphosphonic acid), alendronic acid, 2 -Aminoethyl phosphonic acid (2-Aminoethylphosphonic acid), methyl phosphonic acid (methylphosphonic acid) and p-hydroxyphenyl phosphonic acid (p-hydroxypheny phosphonic acid) may include one or more compounds selected from.

In addition, in the step of applying the composition to the electrode for a fuel cell, the weight per unit area (M / A) of the organic compound having the phosphonic acid group applied on the catalyst layer of the electrode for the fuel cell is 0.1 mg / cm ² to 15 It is characterized by being mg / cm ² .

When the weight per unit area (M / A) of the organic compound having a phosphonic acid group is less than 0.1 mg / cm ² , it is not preferable because it cannot sufficiently provide a proton conductivity improving effect.

When the weight per unit area of the organic compound having the phosphonic acid group (M / A) is more than 15 mg / cm ² , the organic compound having the phosphonic acid group can screen the metal catalyst and lower the activity of the catalyst layer. Do not.

Hereinafter, the present invention will be described in more detail through preparation examples, comparative examples, and experimental examples. However, the present invention is not limited to the following manufacturing examples and experimental examples.

<Production Example 1: Preparation of a membrane electrode assembly in which an organic compound containing phosphonic acid is applied on a catalyst layer>

A binder solution was prepared by mixing polyvinylidene fluoride (PVDF), a binder material, with N-methyl-2-pyrrolidone (NMP), an organic solvent. The viscosity increasing agent was added to the binder solution, followed by further mixing. Then, a binder-catalyst mixture solution was prepared by adding a PtCo / C (50 wt%, TKK corp.) Catalyst to the binder solution to which the viscosity increasing agent was added. At this time, the composition ratio (mass ratio) of the catalyst: binder in the binder-catalyst mixed solution was prepared to be 4: 1. The binder-catalyst mixture solution was mixed with a ball mill (250 rpm) for 1 hour, and then bubbles were removed through rotation. The bubble-removed binder-catalyst mixture solution was bar-coated on a gas diffusion layer (GDL, 3.2 x 3.2 cm ² , 320 nm thickness) to form a catalyst layer. Then, using a vacuum oven (vacuum oven) to dry at about 60 ° C to prepare an electrode for a fuel cell. A coating solution was prepared by mixing vinylphosphonic acid in a water solvent. At this time, the concentration of vinylphosphonic acid (vinylphosphonic acid) in the coating solution was prepared to be 20 wt%. 0.145 ml of the coating solution was applied on the catalyst layer of the electrode for the fuel cell, wherein the weight per unit area (M / A) of vinylphosphonic acid was 3.1 mg / cm ² . Then, it was dried at about 80 ° C to prepare a cathode electrode for a high-temperature polymer fuel cell. In addition to the cathode electrode, an anode electrode containing a PtRu / C metal catalyst and a Celtec® electrolyte membrane were used to prepare a membrane electrode assembly.

<Production Examples 2 to 4>

In Preparation Example 1, a membrane electrode assembly was manufactured in the same manner as in Production Example 1, except that the coating amount of the coating solution was changed. At this time, in Production Examples 2 to 4, the coating amounts of the coating solutions were prepared to be 0.29 ml, 0.387 ml, and 0.483 ml, respectively. At this time, the weight per unit area (M / A) of vinylphosphonic acid in Preparation Examples 2 to 4 was 6.3 mg / cm ² , 8.6 mg / cm ² , and 10.5 mg / cm ² , respectively.

<Comparative Example 1>

In Preparation Example 1, a membrane electrode assembly was manufactured in the same manner as in Production Example 1, except that the coating solution was not applied.

<Production Example 5: Preparation of a membrane electrode assembly in which an organic compound containing phosphonic acid is applied to an electrode>

A binder solution was prepared by adding polyphenylene oxide-methylphosphonic acid copolymer (PPO-MPA) as a binder material to a solvent in which N-methyl-2-pyrrolidone (NMP) and Dimethyl Sulfoxide (DMSO) were mixed. The viscosity increasing agent was added to the binder solution, followed by further mixing. Then, a binder-catalyst mixture solution was prepared by adding a Pt / C (50 wt.%, RTX corp.) Catalyst to the binder solution to which the viscosity increasing agent was added. At this time, the composition ratio (mass ratio) of the catalyst: binder in the binder-catalyst mixed solution was prepared to be 4: 1. The binder-catalyst mixture solution was mixed with a ball mill (250 rpm) for 1 hour, and then bubbles were removed through rotation. The bubble-removed binder-catalyst mixture solution was bar-coated on a gas diffusion layer (GDL, 3.2 x 3.2 cm ² , 320 nm thickness) to form a catalyst layer. Then, using a vacuum oven (vacuum oven) to dry at about 60 ° C to prepare an electrode for a fuel cell. A coating solution was prepared by mixing vinylphosphonic acid in a water solvent. At this time, the concentration of vinylphosphonic acid (vinylphosphonic acid) in the coating solution was prepared to be 20 wt.%. 0.058 ml of the coating solution was applied on the catalyst layer of the electrode for the fuel cell, wherein the weight per unit area (M / A) of vinylphosphonic acid was 1.03 mg / cm ² . Then, it was dried at about 80 ° C to prepare a cathode electrode for a high-temperature polymer fuel cell. In addition to the cathode electrode, an anode electrode containing a PtRu / C metal catalyst and a Celtec® electrolyte membrane were used to prepare a membrane electrode assembly.

<Production Example 6 and Production Example 7>

In Preparation Example 5, a membrane electrode assembly was prepared in the same manner as in Production Example 5, except that the coating amount of the coating solution was changed. At this time, the coating amounts of the coating solutions of Preparation Examples 6 and 7 were prepared to be 0.29 ml and 0.386 ml, respectively. At this time, the weight per unit area (M / A) of vinylphosphonic acid in Preparation Examples 5 and 7 was 5.75 mg / cm ² and 9.45 mg / cm ² , respectively.

<Comparative Example 2>

In Preparation Example 5, a membrane electrode assembly was manufactured in the same manner as in Preparation Example 5, except that the coating solution was not applied.

<Experimental Example 1>

An experiment was conducted to confirm the presence of the organic compound containing phosphonic acid in the electrode. To this end, the Cathode electrode prepared according to Preparation Example 1 was measured by P-31 NMR to confirm whether vinylphosphonic acid was present in the electrode. At this time, the Cathode electrode was dissolved in DMSO-D6, the supported catalyst was filtered through a filter, and then P-31 NMR was measured.

Figure 1 (a) is a graph showing the P-31 NMR measurement results of the Cathode electrode prepared according to Preparation Example 1.

1 (b) is a graph showing the NMR peak of a sample in which vinylphosphonic acid is dissolved in DMSO-D6.

1 (a) and (b), the NMR peak of the electrode for a high-temperature polymer fuel cell according to the present invention corresponds to the NMR peak of the vinylphosphonic acid (vinylphosphonic acid) shown in FIG. 1 (b) It can be confirmed that the vinyl phosphonic acid (vinylphosphonic acid) is present in the electrode.

<Experimental Example 2>

An experiment was conducted to compare the performance of the membrane electrode assembly according to whether or not an organic compound containing phosphonic acid was applied. To this end, a high-temperature polymer fuel cell was manufactured using the membrane electrode assemblies prepared according to Preparation Examples 1 to 4 and Comparative Example 1, and experiments were conducted to compare their performance.

2 is a graph of measuring voltages according to current density (A / cm ² ) of a high-temperature polymer fuel cell using membrane electrode assemblies according to Preparation Examples 1 to 4 and Comparative Example 1;

3 is a graph showing normalizaing the results measured according to FIG. 2 according to the platinum (Pt) loading amount.

Table 1 below summarizes the results measured according to Experimental Example 2.

VPA loading
(mg / cm ² ) Pt loading
(mg / cm ² ) Voltage at 0.2 A / cm ²
(V) Voltage at 0.2 A / mg _pt
(V) Preparation Example 1 3.1 0.93 0.645 0.650 Preparation Example 2 6.3 0.96 0.656 0.656 Preparation Example 3 8.6 1.06 0.660 0.652 Preparation Example 4 10.5 1.00 0.648 0.648 Comparative Example 1 - 1.00 0.636 0.636

2 and 3, compared to Comparative Example 1 in which vinylphosphonic acid (vinylphosphonic acid, VPA) was not applied to the electrode, the same currents in Preparation Examples 1 to 4 in which vinylphosphonic acid (VPA) was applied It can be seen that the voltage and power values are high at the density (A / cm ² ).

Specifically, referring to Table 1, in the case of Comparative Example 1 in which vinylphosphonic acid (VPA) was not applied on the catalyst layer, the voltage was 0.636 V at 0.2 A / cm ² and 0.636 at 0.2 A / mg _pt . It can be confirmed that the value of V is shown. On the other hand, in the case of Preparation Examples 1 to 4, the VPA loadings were 6.3 mg / cm ² , 8.6 mg / cm ² , and 10.5 mg / cm ² , respectively. In addition, voltages of Preparation Examples 1 to 4 show values of 0.645, 0.656, and 0.660 V, respectively, at 0.2 A / cm ² , and values of 0.650 V, 0.656 V, 0.652 V, and 0.648 V, respectively, at 0.2 A / mg _pt . You can confirm that. Through these results, in the case of a fuel cell coated with vinylphosphonic acid (VPA) on the catalyst layer, the same current density (A / cm ² ), the same as compared with the case where the vinylphosphonic acid (VPA) is not applied It can be seen that the voltage and power values measured at the Pt loading amount are large, and thus it can be seen that the performance of the fuel cell is excellent.

At this time, the voltage and power values of the fuel cell tended to increase and decrease again as the weight (M / A) per unit area of vinylphosphonic acid (VPA) increased, which was excessively applied to VPA. In this case, it is considered that the catalyst activity is lowered by screening the metal catalyst. At this time, the voltage value at 0.2 A / cm ² is the best when the weight per unit area of vinylphosphonic acid (VPA) is 8.6 mg / cm ² , and the voltage value at 0.2 A / mg _pt Silver vinyl phosphonic acid (vinylphosphonic acid, VPA) weight per unit area (M / A) of 6.3 mg / cm ^{2 It} can be seen that the best.

<Experimental Example 3>

An experiment was conducted to compare the performance of a membrane electrode assembly to which a polyphenylene oxide-methylphosphonic acid copolymer (PPO-MPA) binder was applied depending on whether an organic compound containing phosphonic acid was applied. To this end, high-temperature polymer fuel cells were prepared using membrane electrode assemblies prepared according to Preparation Examples 5 to 7 and Comparative Example 2, and experiments were conducted to compare their performance.

4 is a graph measuring voltage and power according to current density (A / cm ² ) of a high-temperature polymer fuel cell using a membrane electrode assembly according to Preparation Examples 5 to 7 and Comparative Example ² .

Table 2 below is a table summarizing the results measured according to Experimental Example 3.

VPA loading
(mg / cm ² ) Pt loading
(mg / cm ² ) Voltage at 0.2 A / cm ²
(V) Peak power (W) Preparation Example 5 1.03 1.06 0.393 0.636 Preparation Example 6 5.75 1.06 0.498 0.825 Preparation Example 7 9.45 1.04 0.439 0.692 Comparative Example 2 - 1.06 - 0.322

5, compared to the case of Comparative Example 1 in which vinylphosphonic acid (vinylphosphonic acid, VPA) was not applied to the electrode, the voltage in Preparation Examples 5 to 7 in which vinylphosphonic acid (VPA) was applied to the electrode And it can be seen that the power value is high.

Specifically, referring to Table 2, in the case of Comparative Example 1 in which vinylphosphonic acid (VPA) was not applied, the voltage (V) at 0.2 A / cm ² is a value less than or equal to the measurement range (about 0.3 V or more). And the power (W) was measured to be 0.322 W. In contrast, in the case of Preparation Examples 5 to 7 in which vinylphosphonic acid (VPA) was applied, the voltage (V) at 0.2 A / cm ² was measured to be 0.393 V, 0.498 V, and 0.439 V, respectively, and power (W). Was measured as 0.636 W, 0.825 W, and 0.692 W, respectively. Through these results, when vinyl phosphonic acid (vinylphosphonic acid, VPA) is applied on the catalyst layer compared to when vinyl phosphonic acid (vinylphosphonic acid, VPA) is not applied on the catalyst layer, the same current density (A / cm ² ), the same It can be seen that the voltage and power values measured at the Pt loading amount are large, and thus it can be seen that the performance of the fuel cell is excellent.

At this time, the voltage and power values of the fuel cell tended to increase and decrease again as the weight per unit area of vinylphosphonic acid (VPA) increased (M / A), and this tended to decrease again. , VPA) is excessively applied, and it is considered that the catalyst activity is lowered by screening the metal catalyst. At this time, when the weight per unit area of vinylphosphonic acid (VPA) (M / A) is 5.75 mg / cm ² , it can be seen that voltage and power are the best.

<Experimental Example 4>

An experiment was conducted to confirm the presence of the organic compound containing phosphonic acid in the electrode. To this end, two Cathode electrodes according to Preparation Example 2 were prepared. One of the two Cathode electrodes prepared above was heat treated at 80 ° C. for about 1 hour, and the other electrode was heat treated at 150 ° C. for about 1 hour. Thereafter, FT-IR measurement was performed on the two cathode electrodes. Separately, two Cathode electrodes according to Preparation Example 6 were prepared, one of which was heat treated at 80 ° C for about 1 hour, and the other electrode was heat treated at 150 ° C for about 1 hour. Thereafter, FT-IR measurement was performed on the two cathode electrodes. At this time, the experiment was performed by setting the Cathode electrode before applying the vinylphosphonic acid (VPA) as an FT-IR background.

5 (a) is a graph showing the FT-IR measurement results of the Cathode electrode prepared according to Preparation Example 2.

5 (b) is a graph showing the results of FT-IR measurement of the Cathode electrode prepared according to Preparation Example 6.

5 (a) and (b), 1621 cm ^-1 , 1415 cm ^-1 , 1240 cm ^-1 , 1070 cm ^-1 , 960 cm ^-1 , 751 cm ^-1 , 620 cm ^-1 vicinity Corresponding to the stretching vibration of POH bond, Scissoring vibration of C = CH bond, stretching vibration of P = O bond, stretching vibration of PO bond, stretching vibration of POH bond, bending vibration of CP bond, respectively Peaks were observed, from which it can be seen that the cathode electrode according to Preparation Example 2 and Preparation Example 6 contains vinylphosphonic acid (VPA).

However, referring to (b) of FIG. 5, in the case of a temperature condition of 150 ° C., a change was observed at a peak around 1240 cm ⁻¹ corresponding to P = O stretching vibration, which is a PPO used as a binder in Preparation Example 6 -It is judged that MPA reacts with vinylphosphonic acid (VPA) at high temperature.

The above description of the present invention is for illustration only, and a person having ordinary knowledge in the technical field to which the present invention pertains can understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined form.

The scope of the present invention is indicated by the following claims, and all changes or modifications derived from the meaning and scope of the claims and equivalent concepts should be interpreted to be included in the scope of the present invention.

Claims (16)

Gas diffusion layer;
A catalyst layer formed on the gas diffusion layer; And
An electrode for a high-temperature polymer fuel cell comprising an organic compound having a phosphonic acid group applied on the catalyst layer. According to claim 1,
The organic compound having a phosphonic acid group is a single molecule having a phosphonic acid group; Monomer; Or a high-temperature polymer fuel cell electrode comprising a polymer compound having a phosphonic acid group in the main chain and / or side chain. According to claim 1,
The organic compound having a phosphonic acid group is vinylphosphonic acid, isopropenylphosphonic acid, 1-phenylvinyl phosphonic acid, methylenephosphonic acid (N, N, N ', N'-ethylenediamine tetrakis), 1-Hydroxyethane-1,1-diphosphonic acid, alendronic acid, 2-aminoethylphosphonic acid ( An electrode for a high-temperature polymer fuel cell comprising at least one compound selected from 2-Aminoethylphosphonic acid, methylphosphonic acid, and p-hydroxypheny phosphonic acid. According to claim 1,
The catalyst layer has a thickness of 5 μm to 120 μm, characterized in that the high-temperature polymer fuel cell electrode. According to claim 1,
The electrode for a high-temperature polymer fuel cell, characterized in that the weight per unit area (M / A) of the organic compound having the phosphonic acid group applied on the catalyst layer is 0.1 mg / cm ² to 15 mg / cm ² . According to claim 1,
The catalyst layer is polyvinylidene fluoride, polytetrafluoroethylene, tetrafluoroethylene-hexafluoroethylene copolymer, perfluoroethylene propylene copolymer and polyphenylene oxide-methylphosphonic acid High temperature polymer fuel cell electrode comprising a binder formed of at least one compound selected from the group consisting of copolymers. According to claim 1,
The catalyst layer includes a metal catalyst,
The metal catalyst is an electrode for a high-temperature polymer fuel cell, characterized in that it activates the oxidation reaction of hydrogen and the reduction reaction of oxygen. According to claim 1,
The catalyst layer is platinum; Palladium; An alloy of platinum and one or more metals selected from the group consisting of cobalt, gold, ruthenium, tin, molybdenum, palladium, rhodium, iridium, bismuth, copper, yttrium and chromium; Or an electrode for a high-temperature polymer fuel cell comprising a metal catalyst formed of an alloy of palladium. According to claim 1,
The high-temperature polymer fuel cell electrode exhibits peaks at 1620, 1240, 1070, 960 and 751 cm ^-1 when measured by FT-IR, and the error range of each peak is ± 5 cm ^-1 . Battery electrode. A membrane electrode assembly for a high-temperature polymer fuel cell, comprising the electrode for a high-temperature polymer fuel cell according to any one of claims 1 to 9. A high-temperature polymer fuel cell comprising the electrode for a high-temperature polymer fuel cell according to any one of claims 1 to 9. Preparing a composition comprising an organic compound having a phosphonic acid group; And
Method for manufacturing a high temperature polymer fuel cell electrode comprising the step of applying the composition on the catalyst layer of the electrode for a fuel cell. The method of claim 12,
The electrode for the fuel cell, preparing a binder solution by mixing a binder material in a solvent;
Preparing a binder-catalyst mixed solution by adding a metal catalyst supported on a carbon support to the binder solution; And
Method for manufacturing an electrode for a high-temperature polymer fuel cell, characterized in that it is prepared through the step of forming a catalyst layer by coating the mixed solution on a gas diffusion layer. The method of claim 12,
The organic compound having a phosphonic acid group is a single molecule having a phosphonic acid group; Monomer; Or a method of manufacturing an electrode for a high-temperature polymer fuel cell, comprising a polymer compound having a phosphonic acid group in the main chain and / or side chain. The method of claim 12,
The organic compound having the phosphonic acid group is vinyl phosphonic acid, isopropenyl phosphonic acid, 1-phenylvinyl phosphonic acid, methylenephosphonic acid (N, N , N ', N'-ethylenediamine tetrakis), 1-Hydroxyethane-1,1-diphosphonic acid, alendronic acid, 2-aminoethylphos Electrode for a high-temperature polymer fuel cell comprising at least one compound selected from phosphonic acid (2-Aminoethylphosphonic acid), methylphosphonic acid (methylphosphonic acid) and p-hydroxyphenyl phosphonic acid (p-hydroxypheny phosphonic acid) Method of manufacturing. The method of claim 12,
In the step of applying the composition on the catalyst layer of the electrode for a fuel cell, the weight per unit area (M / A) of the organic compound having the phosphonic acid group applied on the catalyst layer is 0.1 mg / cm ² to 15 mg / cm Method of manufacturing an electrode for a high-temperature polymer fuel cell, characterized in that ² .

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