KR20200043579A - Non-platinum based oxygen reduction catalyst and method for its preparation - Google Patents

Abstract

An embodiment of the present invention is to provide a non-platinum-based oxygen reduction active catalyst. The non-platinum-based oxygen reduction active catalyst according to an embodiment of the present invention has improved oxygen reduction activities as transition metal is doped.

Description

Non-platinum based oxygen reduction catalyst and method for its preparation

The present invention relates to a non-platinum-based oxygen reduction activity catalyst, and more particularly, to a non-platinum-based oxygen reduction activity catalyst supported on a carbon carrier.

Since Sir William Grove reported fuel cells using hydrogen and oxygen as fuels and oxidants, respectively, on platinum electrodes immersed in dilute sulfuric acid electrolytes, fuel cells have been developed in various types according to the electrolyte used. come. However, regardless of its type, fuel cells are highly regarded as the most excellent source of electrochemical energy that can be used in combustion engines or batteries. Fuel cells can not only be used continuously as long as fuel is injected, such as combustion engines, but also convert chemical energy into electrical energy. The most prominent thing about fuel cells is that, unlike conventional internal combustion engines, their efficiency is not limited by the Carnot limitation. Fuel cells are reported to have an efficiency of converting fuel to electrochemical energy of about 40-50%, and have a maximum efficiency of 90% in cogeneration.

The polymer electrolyte membrane fuel cell can be largely classified into an anode part that oxidizes hydrogen, a cathode part that reduces oxygen, and an electrolyte in which ions move between them. At this time, platinum is the most representative electrode catalyst used for both electrodes. While the oxidation reaction of hydrogen on the platinum electrode is fast, the oxygen reduction reaction (ORR) on another platinum electrode is very slow compared to that of hydrogen. Therefore, the overall reaction rate is determined by the ORR rate. Moreover, the slower ORR induces a high overpotential to the cathode electrode, thereby lowering the efficiency of the fuel cell. Therefore, the most urgent problem to be solved in the current PEMFC is to make the slow ORR on the cathode fast. On the other hand, since platinum electrodes are very expensive, it is required to develop a more efficient and inexpensive non-platinum electrode catalyst.

Korea Registered Patent No. 10-1494432

The technical problem to be achieved by the present invention is to provide a non-platinum-based oxygen reduction activity catalyst for a fuel cell.

The technical problem to be achieved by the present invention is to provide a highly efficient non-platinum oxygen reduction active catalyst for a fuel cell.

The technical problems to be achieved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by those skilled in the art from the following description. There will be.

In order to achieve the above technical problem, an embodiment of the present invention provides a non-platinum oxygen reduction active catalyst.

In an embodiment of the present invention, the non-platinum-based oxygen reduction activity catalyst is characterized in that the ternary alloy catalyst particles including palladium (Pd), iridium (Ir) and transition metal are supported on a carbon carrier.

At this time, the palladium: iridium: lanthanum (La) or scandium (Sc) is characterized in that it has a weight ratio of 30 to 50: 5 to 15: 1.

At this time, the ternary alloy catalyst particles are characterized in having a loading ratio supported by 10% to 60% by weight relative to the total weight of the ternary alloy catalyst supported on the carbon carrier.

In this case, the carbon carrier may include carbon black, carbon nanotubes, carbon nanofibers, graphene, activated carbon, mesoporous carbon structure, or hierarchical multi-structure carbon structure.

At this time, the carbon carrier is characterized in that doped with iron (Fe) and / or nitrogen (N).

In order to achieve the above technical problem, an embodiment of the present invention provides a method for preparing a non-platinum oxygen reducing active catalyst.

In an embodiment of the present invention, the non-platinum-based oxygen reduction activity catalyst manufacturing method comprises dispersing a carbon carrier in a polyhydric alcohol to prepare a carbon carrier dispersion, a palladium precursor, an iridium precursor, and a lanthanum (La) in the carbon carrier dispersion. Preparing a mixture solution in which the palladium precursor, the iridium precursor and the lanthanum (La) precursor or the scandium (Sc) precursor are adsorbed on the carbon carrier by adding a precursor or a scandium (Sc) precursor, the palladium precursor from the mixture, Preparing a ternary alloy catalyst solution in which ternary alloy catalyst particles are supported on the carbon carrier by reducing iridium precursor and lanthanum (La) precursor or scandium (Sc) precursor through reflux under basic conditions, and the ternary alloy And recovering the ternary alloy catalyst from the catalyst solution.

In this case, the carbon carrier may include carbon black, carbon nanotubes, carbon nanofibers, graphene, activated carbon, mesoporous carbon structures, or hierarchical multi-structure carbon structures.

At this time, the step of preparing the mixture solution is characterized in that the palladium precursor: iridium precursor: lanthanum (La) precursor or scandium (Sc) precursor is added in a weight ratio of 30 to 50: 5 to 15: 1.

At this time, the step of preparing the ternary alloy catalyst solution is characterized in that it is performed under the conditions of pH 10.5 to pH 11.5.

At this time, the step of preparing the ternary alloy catalyst solution is characterized in that it is performed at 100 ° C to 130 ° C.

At this time, the ternary alloy catalyst particles are characterized in having a loading ratio supported by 10% to 60% by weight relative to the total weight of the ternary alloy catalyst supported on the carbon carrier.

In order to achieve the above technical problem, an embodiment of the present invention provides a method for producing a non-platinum oxygen reduction active catalyst.

In an embodiment of the present invention, the non-platinum-based oxygen reduction activity catalyst manufacturing method comprises dispersing a carbon carrier in a polyhydric alcohol to prepare a carbon carrier dispersion, a palladium precursor, an iridium precursor, and a lanthanum (La) in the carbon carrier dispersion. Preparing a mixture solution in which the palladium precursor, the iridium precursor and the lanthanum (La) precursor or the scandium (Sc) precursor are adsorbed on the carbon carrier by adding a precursor or a scandium (Sc) precursor, the palladium precursor from the mixture, The iridium precursor and the lanthanum (La) precursor or the scandium (Sc) precursor are reduced through an electron beam reduction method under basic conditions to prepare a ternary alloy catalyst solution in which ternary alloy catalyst particles are supported on the carbon carrier and the ternary system And recovering the ternary alloy catalyst from the alloy catalyst solution.

In this case, the carbon carrier may include carbon black, carbon nanotubes, carbon nanofibers, graphene, activated carbon, mesoporous carbon structures, or hierarchical multi-structure carbon structures.

At this time, the step of preparing the mixture solution is characterized in that the palladium precursor: iridium precursor: lanthanum (La) precursor or scandium (Sc) precursor is added at a molar ratio of 30 to 50: 5 to 15: 1.

At this time, the step of preparing the ternary alloy catalyst solution is characterized in that it is carried out at pH 9.5 to pH 10.5.

At this time, the step of preparing the ternary alloy catalyst solution is characterized by irradiating an electron beam of 0.1MeV to 1MeV to the mixture solution adsorbed with the palladium precursor, iridium precursor and lanthanum (La) precursor or scandium (Sc) precursor. do.

At this time, the ternary alloy catalyst particles are characterized in having a loading ratio supported by 10% to 60% by weight relative to the total weight of the ternary alloy catalyst supported on the carbon carrier.

According to the embodiment of the present invention, it is possible to provide a non-platinum-based oxygen reduction active catalyst.

According to the embodiment of the present invention, it is possible to provide a highly efficient non-platinum oxygen reduction active catalyst.

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 flow chart showing a method for preparing a non-platinum oxygen reduction active catalyst according to an embodiment of the present invention.
Figure 2 is a flow chart showing a method for producing a non-platinum oxygen reduction active catalyst according to an embodiment of the present invention.
3 is a SEM photograph of a non-platinum oxygen reduction active catalyst according to an embodiment of the present invention.
Figure 4 is a graph showing the current density-voltage characteristics of the oxygen reduction active catalyst according to an embodiment or comparative example of the present invention.

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.

A method for preparing a non-platinum oxygen reducing active catalyst according to an embodiment of the present invention will be described.

1 is a flow chart showing a method for preparing a non-platinum oxygen reduction active catalyst according to an embodiment of the present invention.

Referring to Figure 1, the non-platinum oxygen reduction active catalyst manufacturing method is a step of preparing a carbon carrier dispersion by dispersing a carbon carrier in polyhydric alcohol (S100), palladium precursor, iridium precursor and lanthanum (La) in the carbon carrier dispersion ) Adding a precursor or a scandium (Sc) precursor to prepare a mixture solution in which the palladium precursor, iridium precursor and lanthanum (La) precursor or scandium (Sc) precursor are adsorbed on the carbon carrier (S200), from the mixture Preparing the ternary alloy catalyst solution in which ternary alloy catalyst particles are supported on the carbon carrier by reducing the palladium precursor, iridium precursor and lanthanum (La) precursor or scandium (Sc) precursor through reflux under basic conditions ( S300) and recovering the ternary alloy catalyst from the ternary alloy catalyst solution (S400).

At this time, the step of preparing the carbon carrier dispersion (S100) may be a step of dispersing the carbon carrier in a solvent.

At this time, the solvent may include ethylene glycol or polyhydric alcohol.

In this case, the carbon carrier may include carbon black, carbon nanotubes, carbon nanofibers, graphene, activated carbon, mesoporous carbon structures, or hierarchical multi-structure carbon structures.

There is a research result that the step of transferring electrons to oxygen molecules is a reaction rate determination step in the reduction reaction of oxygen molecules. Therefore, in order to cause the reduction reaction of the oxygen molecules to occur quickly, it is important to quickly transfer electrons to the oxygen molecules. Therefore, in the oxygen reduction activity catalyst, when the metal catalyst is doped with a transition metal, the transition metal can supply electrons to the metal catalyst, thereby improving the oxygen reduction activity of the metal catalyst.

At this time, the step (S200) of preparing the mixture solution is characterized in that the palladium precursor: iridium precursor: lanthanum (La) precursor or scandium (Sc) precursor is added in a weight ratio of 30 to 50: 5 to 15: 1. .

At this time, when the lanthanum (La) or scandium (Sc) is included less than the weight ratio, the electron supply effect of the transition metal is low, and the oxygen reduction activity of the catalyst may be lowered.

At this time, when the lanthanum (La) or scandium (Sc) is included in excess of the weight ratio, a problem of deterioration of oxygen reduction activity by generation of lanthanum (La) oxide or scandium (Sc) oxide may occur.

Preferably, the step (S300) of preparing the ternary alloy catalyst solution may be performed at pH 10.5 to pH 11.5.

Preferably, the step of preparing the ternary alloy catalyst solution (S300) may be performed at 100 ° C to 130 ° C.

The recovering step (S400) may be performed through filtration, washing or drying.

Preferably, the step of recovering (S400) may include a step of heat treatment (not shown).

Preferably, the step of heat treatment (not shown) may be performed in an inert atmosphere of 200 ° C to 500 ° C.

Preferably, the inert atmosphere may be an inert gas atmosphere including nitrogen (N ₂ ), hydrogen (H ₂ ), or argon (Ar) gas.

Preferably, the ternary alloy catalyst particles may have a loading ratio of 10% to 60% by weight based on the total weight of the ternary alloy catalyst supported on the carbon carrier.

At this time, when the loading rate of the ternary alloy catalyst particles is less than 10%, oxygen reduction activity may be deteriorated due to low catalyst concentration.

At this time, when the loading rate of the ternary alloy catalyst particles is more than 60%, the catalyst particles may not be uniformly distributed on the carbon carrier due to the high concentration of catalyst particles.

Preparation Example 1

According to an embodiment of the present invention, a non-platinum oxygen reducing activity catalyst was prepared.

First, the carbon carrier was dissolved in a solvent composed of ethylene glycol and water. Next, sonication was performed for 15 minutes to disperse the carbon carrier in the solvent to prepare a carbon carrier dispersion. Next, the palladium precursor, iridium precursor and lanthanum (La) precursor or scandium (Sc) precursor are added to the carbon carrier dispersion to add the palladium precursor, iridium precursor and lanthanum (La) precursor or scandium (Sc) to the carbon carrier. A mixture solution in which the precursor was adsorbed was prepared. Next, the pH of the mixture solution was adjusted to pH 11 through an aqueous NaOH solution. Next, the mixture solution in a basic atmosphere is refluxed to reduce the palladium precursor, iridium precursor, and lanthanum (La) precursor or scandium (Sc) precursor, so that a ternary alloy catalyst solution in which ternary alloy catalyst particles are supported on the carbon carrier Was prepared. Next, filter filtration was performed to recover the ternary alloy catalyst from the ternary alloy catalyst solution. Next, the ternary alloy catalyst recovered using distilled water was washed several times, and then freeze-dried to prepare a ternary alloy catalyst. Next, the ternary alloy catalyst was heat treated for 1 hour at 300 ° C in an inert gas (N ₂ : H ₂ = 2: 1) atmosphere. At this time, La or Sc was used as the transition metal.

Example 1

According to the method for preparing a non-platinum-based oxygen reduction active catalyst according to an embodiment of the present invention, Pd ₄ IrSc _0.1 is supported on a carbon carrier to which iron (Fe) and nitrogen (N) have been added through Preparation Example 1 According to the non-platinum-based oxygen reduction activity catalyst was prepared. The SEM photograph of this is shown in FIG. 3. Table 1 shows the current density characteristics and the half-cell characteristics.

Example 2

A non-platinum oxygen reduction activity catalyst according to an embodiment of the present invention is supported by supporting Pd ₄ IrSc _0.1 on a carbon carrier having mesopores through Production Example 1 according to a method for preparing a non-platinum oxygen reduction activity catalyst according to an embodiment of the present invention. Was prepared.

Comparative Example 1

In order to compare with the example of the present invention, palladium (Pd) was prepared on the carbon black carbon carrier through Preparation Example 1 to prepare an oxygen reduction activity catalyst. Table 1 shows the current density characteristics and the half-cell characteristics.

Comparative Example 2

In order to compare with the example of the present invention, Pd ₄ Ir was prepared on the carbon black carbon carrier through Preparation Example 1 to prepare an oxygen reduction activity catalyst. Table 1 shows the current density characteristics and the half-cell characteristics.

According to the embodiment of the present invention, a non-platinum-based oxygen reduction active catalyst can be prepared.

According to the embodiment of the present invention, a highly efficient non-platinum oxygen reduction active catalyst can be prepared.

According to an embodiment of the present invention, the oxygen reduction activity of the metal particles is improved through the doping of the transition metal, so that a highly efficient non-platinum oxygen reduction activity catalyst can be prepared.

According to an embodiment of the present invention, a high-efficiency non-platinum oxygen reduction active catalyst can be prepared through metal particles doped with transition metals and carbon carriers doped with hetero elements.

A method for preparing a non-platinum oxygen reducing active catalyst according to an embodiment of the present invention will be described.

Figure 2 is a flow chart showing a method for producing a non-platinum oxygen reduction active catalyst according to an embodiment of the present invention.

Referring to FIG. 2, the method for preparing a non-platinum oxygen reduction active catalyst comprises dispersing a carbon carrier in polyhydric alcohol to prepare a carbon carrier dispersion, a palladium precursor, an iridium precursor, and a lanthanum (La) precursor in the carbon carrier dispersion, or Preparing a mixture solution in which the palladium precursor, the iridium precursor and the lanthanum (La) precursor or the scandium (Sc) precursor are adsorbed on the carbon carrier by adding a scandium (Sc) precursor; and the palladium precursor and iridium precursor from the mixture And preparing a ternary alloy catalyst solution in which ternary alloy catalyst particles are supported on the carbon carrier by reducing the lanthanum (La) precursor or the scandium (Sc) precursor under basic conditions through an electron beam reduction method, and the ternary alloy catalyst. And recovering the ternary alloy catalyst from a solution.

At this time, the step of preparing the carbon carrier dispersion (S500) may be a step of dispersing the carbon carrier in a solvent.

At this time, the solvent may include ethylene glycol or polyhydric alcohol.

In this case, the carbon carrier may include carbon black, carbon nanotubes, carbon nanofibers, graphene, activated carbon, mesoporous carbon structures, or hierarchical multi-structure carbon structures.

There is a research result that the step of transferring electrons to oxygen molecules is a reaction rate determination step in the reduction reaction of oxygen molecules. Therefore, in order to cause the reduction reaction of the oxygen molecules to occur quickly, it is important to quickly transfer electrons to the oxygen molecules. Therefore, in the oxygen reduction activity catalyst, when the metal catalyst is doped with a transition metal, the transition metal can supply electrons to the metal catalyst, thereby improving the oxygen reduction activity of the metal catalyst.

At this time, the step (S600) of preparing the mixture solution is characterized in that the palladium precursor: iridium precursor: lanthanum (La) precursor or scandium (Sc) precursor is added in a weight ratio of 30 to 50: 5 to 15: 1. .

At this time, when the lanthanum (La) or scandium (Sc) is included less than the weight ratio, the electron supply effect of the transition metal is low, and the oxygen reduction activity of the catalyst may be lowered.

At this time, when the lanthanum (La) or scandium (Sc) is included in excess of the weight ratio, a problem of deterioration of oxygen reduction activity by generation of lanthanum (La) oxide or scandium (Sc) oxide may occur.

At this time, the step (S700) of preparing the ternary alloy catalyst solution is to irradiate an electron beam of 0.1MeV to 1MeV to a mixture solution in which the palladium precursor, iridium precursor and lanthanum (La) precursor or scandium (Sc) precursor are adsorbed. It is characterized by.

At this time, when irradiating an electron beam of less than 0.1 MeV in the step (S700) of preparing the ternary alloy catalyst solution, the energy of the electron beam is low, so it may be difficult to reduce the lanthanum (La) precursor or scandium (Sc) precursor.

At this time, when the electron beam of more than 1 MeV is irradiated in the step (S700) of preparing the ternary alloy catalyst solution, efficiency and economic efficiency may be reduced.

Preferably, the step (S700) of preparing the ternary alloy catalyst solution may be performed under conditions of pH 9.5 to pH 10.5.

Preferably, the step (S700) of preparing the ternary alloy catalyst solution may be performed at 100 ° C to 130 ° C.

The recovering step (S400) may be performed through filtration, washing or drying.

Preferably, the step of recovering (S800) may include a step of heat treatment (not shown).

Preferably, the step of heat treatment (not shown) may be performed in an inert atmosphere of 200 ° C to 500 ° C.

Preferably, the inert atmosphere may be an inert gas atmosphere including nitrogen (N ₂ ), hydrogen (H ₂ ), or argon (Ar) gas.

Preferably, the ternary alloy catalyst particles may have a loading ratio of 10% to 60% by weight based on the total weight of the ternary alloy catalyst supported on the carbon carrier.

At this time, when the loading rate of the ternary alloy catalyst particles is less than 10%, oxygen reduction activity may be deteriorated due to low catalyst concentration.

At this time, when the loading rate of the ternary alloy catalyst particles is more than 60%, the catalyst particles may not be uniformly distributed on the carbon carrier due to the high concentration of catalyst particles.

Preparation Example 2

According to an embodiment of the present invention, a non-platinum oxygen reducing activity catalyst was prepared.

First, the carbon carrier was dissolved in a solvent composed of diethylene glycol, secondary alcohol and water. Next, sonication was performed for 10 minutes to disperse the carbon carrier in the solvent to prepare a carbon carrier dispersion. Next, the palladium precursor, iridium precursor and lanthanum (La) precursor or scandium (Sc) precursor are added to the carbon carrier dispersion to add the palladium precursor, iridium precursor and lanthanum (La) precursor or scandium (Sc) to the carbon carrier. A mixture solution in which the precursor was adsorbed was prepared. Next, the pH of the mixture solution was adjusted to pH 10 through an aqueous NaOH solution. Next, by irradiating a mixture solution of a basic atmosphere with a 0.2 MeV electron beam for 40 minutes to reduce the palladium precursor, iridium precursor and lanthanum (La) precursor or scandium (Sc) precursor, ternary alloy catalyst particles are deposited on the carbon carrier. A supported ternary alloy catalyst solution was prepared. Next, filter filtration was performed to recover the ternary alloy catalyst from the ternary alloy catalyst solution. Next, the ternary alloy catalyst recovered by using distilled water was washed several times and then oven dried to prepare a ternary alloy catalyst. Next, the ternary alloy catalyst was heat treated at 300 ° C for 1 hour in an inert gas (Ar: H ₂ = 4: 1) atmosphere. At this time, La or Sc was used as the transition metal.

Example 3

A non-platinum oxygen-reducing active catalyst according to an embodiment of the present invention is prepared by supporting Pd ₄ IrLa _0.1 on a carbon black carbon carrier through Production Example 2 according to a method for preparing a non-platinum-based oxygen reducing active catalyst according to an embodiment of the present invention. Did. Table 1 shows the current density characteristics and the half-cell characteristics.

Example 4

A non-platinum oxygen-reducing active catalyst according to an embodiment of the present invention is prepared by supporting Pd ₄ IrSc _0.1 on a carbon black carbon carrier through Production Example 2 according to a method for preparing a non-platinum-based oxygen reducing active catalyst according to an embodiment of the present invention. Did. Table 1 shows the current density characteristics and the half-cell characteristics.

Comparative Example 3

In order to compare with the example of the present invention, Pd ₄ Ir was supported on a carbon black carbon carrier through Preparation Example 2 to prepare an oxygen reduction activity catalyst. Table 1 shows the current density characteristics and the half-cell characteristics.

Comparative Example 4

Compared with the embodiment of the present invention, a carbon carrier to which iron and nitrogen was added was prepared. Table 1 shows the current density characteristics and the half-cell characteristics.

According to the embodiment of the present invention, a non-platinum-based oxygen reduction active catalyst can be prepared.

According to the embodiment of the present invention, a highly efficient non-platinum oxygen reduction active catalyst can be prepared.

According to an embodiment of the present invention, the oxygen reduction activity of the metal particles is improved through the doping of the transition metal, so that a highly efficient non-platinum oxygen reduction activity catalyst can be prepared.

According to an embodiment of the present invention, a highly efficient non-platinum oxygen reduction active catalyst may be prepared by reducing a lanthanum (La) precursor or a scandium (Sc) precursor through an electron beam.

According to an embodiment of the present invention, a high-efficiency non-platinum oxygen reduction active catalyst can be prepared through metal particles doped with transition metals and carbon carriers doped with hetero elements.

A non-platinum oxygen reduction active catalyst according to an embodiment of the present invention will be described.

In an embodiment of the present invention, the non-platinum-based oxygen reduction activity catalyst is characterized in that the ternary alloy catalyst particles including palladium (Pd), iridium (Ir) and transition metal are supported on a carbon carrier.

There is a research result that the step of transferring electrons to oxygen molecules is a reaction rate determination step in the reduction reaction of oxygen molecules. Therefore, in order to cause the reduction reaction of the oxygen molecules to occur quickly, it is important to quickly transfer electrons to the oxygen molecules. Therefore, in the oxygen reduction activity catalyst, when the metal catalyst is doped with a transition metal, the transition metal can supply electrons to the metal catalyst, thereby improving the oxygen reduction activity of the metal catalyst.

In this case, the transition metal may include lanthanum (La) or scandium (Sc).

At this time, the palladium: iridium: lanthanum (La) or scandium (Sc) is characterized in that it has a weight ratio of 30 to 50: 5 to 15: 1.

At this time, when the lanthanum (La) or scandium (Sc) is included less than the weight ratio, the electron supply effect of the transition metal is low, and thus the oxygen reduction activity of the catalyst may be lowered.

In this case, when the lanthanum (La) or scandium (Sc) is included in excess of the weight ratio, a problem of deterioration of oxygen reduction activity by generation of lanthanum (La) oxide or scandium (Sc) oxide may occur.

At this time, the ternary alloy catalyst particles are characterized in having a loading ratio supported by 10% to 60% by weight relative to the total weight of the ternary alloy catalyst supported on the carbon carrier.

At this time, when the loading rate of the ternary alloy catalyst particles is less than 10%, oxygen reduction activity may be deteriorated due to low catalyst concentration.

At this time, when the loading ratio of the ternary alloy catalyst particles is more than 60%, the catalyst particles may not be uniformly distributed on the carbon carrier due to the high concentration of catalyst particles.

In this case, the carbon carrier may include carbon black, carbon nanotubes, carbon nanofibers, graphene, mesoporous carbon structures or hierarchical multi-structure carbon structures.

When a hetero element is added to the carbon carrier, oxygen reduction activity may be exhibited by the carbon carrier and the hetero element. Therefore, when the oxygen reduction activity catalyst particles are supported on the carbon carrier to which the hetero element is added, both the carbon carrier and the oxygen reduction activity catalyst have oxygen reduction activity, thereby improving the oxygen reduction activity. In this case, the hetero element may include nitrogen, sulfur, boron, phosphorus, or iron.

At this time, the carbon carrier is characterized in that doped with iron (Fe) and / or nitrogen (N).

3 is a SEM photograph of a non-platinum oxygen reduction active catalyst according to an embodiment of the present invention. Referring to FIG. 3, it can be seen that the non-platinum-based oxygen reduction activity catalyst prepared according to Example 1 of the present invention has even distribution of ternary alloy catalyst particles on the carbon carrier.

Table 1 below is a table showing the current density characteristics and half-cell characteristics of the oxygen reduction active catalyst according to Examples and Comparative Examples of the present invention.

catalyst Catalyst manufacturing method Current density at 0.75V (mA / cm ² ) Half wave potential (E _1/2 , V) Example 1 Pd ₄ IrSc _0.1 / FeN-pC Preparation Example 1 1.157 0.666 Example 2 Pd ₄ IrSc _0.1 / pCMK Preparation Example 1 0.749 0.648 Example 3 Pd ₄ IrLa _0.1 / C Preparation Example 2 0.589 0.614 Example 4 Pd ₄ IrSc _0.1 / C Preparation Example 2 0.409 0.607 Comparative Example 1 Pd / C Preparation Example 1 0.089 0.532 Comparative Example 2 Pd ₄ Ir / C Preparation Example 1 0.314 0.590 Comparative Example 3 Pd ₄ Ir / C Preparation Example 2 0.486 0.613 Comparative Example 4 FeN-pC * - 0.046 0.463

Figure 4 is a graph showing the current density-voltage characteristics of the oxygen reduction active catalyst according to an embodiment or comparative example of the present invention.

Referring to Table 1 and Figure 4, it can be seen that the oxygen reduction activity catalyst according to the embodiment of the present invention shows a superior current density than the oxygen reduction activity catalyst of the comparative example. Therefore, it can be seen that when an oxygen reduction activity catalyst is prepared by doping a transition metal according to an embodiment of the present invention, it can exhibit excellent oxygen reduction activity. Further, Example 1 using a carbon carrier doped with iron and nitrogen shows the best current density, and when a carbon carrier doped with a hetero element is used, that is, when the carrier has oxygen reduction activity, a non-platinum catalyst It can be seen that the synergistic effect can be exerted with the composition.

According to the embodiment of the present invention, it is possible to provide a non-platinum-based oxygen reduction active catalyst.

According to the embodiment of the present invention, it is possible to provide a highly efficient non-platinum oxygen reduction active catalyst.

According to an embodiment of the present invention, the oxygen reduction activity of the metal particles is improved through doping of the transition metal, thereby providing a highly efficient non-platinum oxygen reduction activity catalyst.

According to an embodiment of the present invention, it is possible to provide a high-efficiency non-platinum oxygen reduction active catalyst through a metal carrier doped with a transition metal and a carbon carrier doped with a hetero element.

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 (17)

Carbon carrier; And
A non-platinum oxygen reduction active catalyst comprising ternary alloy catalyst particles comprising palladium (Pd), iridium (Ir) and lanthanum (La) or scandium (Sc) supported on the carbon carrier. According to claim 1,
The palladium: iridium: lanthanum (La) or scandium (Sc) is a non-platinum oxygen reduction activity catalyst, characterized in that it has a weight ratio of 30 to 50: 5 to 15: 1. According to claim 1,
The ternary alloy catalyst particles are non-platinum oxygen reduction active catalysts, characterized in that it has a loading ratio supported by 10 to 60% by weight relative to the total weight of the ternary alloy catalyst supported on the carbon carrier. According to claim 1,
The carbon carrier is a carbon black, carbon nanotubes, carbon nanofibers, graphene, activated carbon, mesoporous carbon structure, or a non-platinum oxygen reduction activity catalyst comprising a multi-layered carbon structure. According to claim 1,
The carbon carrier is a non-platinum oxygen reduction activity catalyst, characterized in that iron (Fe) and / or nitrogen (N) is doped. Dispersing the carbon carrier in a polyhydric alcohol to prepare a carbon carrier dispersion;
The palladium precursor, iridium precursor, and lanthanum (La) precursor or scandium (Sc) precursor are added to the carbon carrier dispersion to give the palladium precursor, iridium precursor, and lanthanum (La) precursor or scandium (Sc) precursor to the carbon carrier. Preparing an adsorbed mixture solution;
From the mixture, the palladium precursor, iridium precursor, and lanthanum (La) precursor or scandium (Sc) precursor are reduced through reflux under basic conditions to prepare a ternary alloy catalyst solution in which ternary alloy catalyst particles are supported on the carbon carrier. To do; And
Method for producing a non-platinum oxygen reduction active catalyst comprising the step of recovering the ternary alloy catalyst from the ternary alloy catalyst solution. The method of claim 6,
The carbon carrier is carbon black, carbon nanotubes, carbon nanofibers, graphene, activated carbon, mesoporous carbon structure or a method for producing a non-platinum oxygen reduction active catalyst comprising a multi-layered carbon structure. The method of claim 6,
The step of preparing the mixture solution is a non-platinum oxygen reduction activity characterized in that the palladium precursor: iridium precursor: lanthanum (La) precursor or scandium (Sc) precursor is added in a weight ratio of 30 to 50: 5 to 15: 1. Method for preparing catalyst. The method of claim 6,
The step of preparing the ternary alloy catalyst solution is a method of preparing a non-platinum oxygen reducing active catalyst, characterized in that it is performed under conditions of pH 10.5 to pH 11.5. The method of claim 6,
The step of preparing the ternary alloy catalyst solution is a method for preparing a non-platinum oxygen reducing active catalyst, characterized in that it is performed at 100 ° C to 130 ° C. The method of claim 6,
The ternary alloy catalyst particle is a method for producing a non-platinum oxygen reduction active catalyst, characterized in that it has a loading ratio of 10 to 60% by weight based on the total weight of the ternary alloy catalyst supported on the carbon carrier. Dispersing the carbon carrier in a polyhydric alcohol to prepare a carbon carrier dispersion;
The palladium precursor, iridium precursor, and lanthanum (La) precursor or scandium (Sc) precursor are added to the carbon carrier dispersion to give the palladium precursor, iridium precursor, and lanthanum (La) precursor or scandium (Sc) precursor to the carbon carrier. Preparing an adsorbed mixture solution;
From the mixture, the palladium precursor, iridium precursor, and lanthanum (La) precursor or scandium (Sc) precursor are reduced by an electron beam reduction method under basic conditions to obtain a ternary alloy catalyst solution in which ternary alloy catalyst particles are supported on the carbon carrier. Manufacturing; And
Method for producing a non-platinum oxygen reduction active catalyst comprising the step of recovering the ternary alloy catalyst from the ternary alloy catalyst solution. The method of claim 12,
The carbon carrier is carbon black, carbon nanotubes, carbon nanofibers, graphene, activated carbon, mesoporous carbon structure or a method for producing a non-platinum oxygen reduction active catalyst comprising a multi-layered carbon structure. The method of claim 12,
The step of preparing the mixture solution is a non-platinum oxygen reduction activity characterized in that the palladium precursor: iridium precursor: lanthanum (La) precursor or scandium (Sc) precursor is added in a weight ratio of 30 to 50: 5 to 15: 1. Method for preparing catalyst. The method of claim 12,
The step of preparing the ternary alloy catalyst solution is a method of preparing a non-platinum oxygen reducing activity catalyst, characterized in that it is performed under conditions of pH 9.5 to pH 10.5. The method of claim 12,
In the step of preparing the ternary alloy catalyst solution, the whitening of the palladium precursor, the iridium precursor and the lanthanum (La) precursor or the scandium (Sc) precursor is irradiated with an electron beam of 0.1 MeV to 1 MeV in a mixture solution adsorbed. Method for producing gold-based oxygen reduction active catalyst. The method of claim 12,
The ternary alloy catalyst particle is a method for producing a non-platinum oxygen reduction active catalyst, characterized in that it has a loading ratio of 10 to 60% by weight based on the total weight of the ternary alloy catalyst supported on the carbon carrier.

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