CN114122413A - Membrane electrode catalyst layer with gradient pore structure and preparation method and application thereof - Google Patents

Membrane electrode catalyst layer with gradient pore structure and preparation method and application thereof Download PDF

Info

Publication number
CN114122413A
CN114122413A CN202111269062.9A CN202111269062A CN114122413A CN 114122413 A CN114122413 A CN 114122413A CN 202111269062 A CN202111269062 A CN 202111269062A CN 114122413 A CN114122413 A CN 114122413A
Authority
CN
China
Prior art keywords
layer
catalyst
small
slurry
noble metal
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202111269062.9A
Other languages
Chinese (zh)
Inventor
栾邹杰
徐一凡
唐厚闻
李红涛
白云飞
孔令兴
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shanghai H Rise New Energy Technology Co Ltd
Original Assignee
Shanghai H Rise New Energy Technology Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shanghai H Rise New Energy Technology Co Ltd filed Critical Shanghai H Rise New Energy Technology Co Ltd
Priority to CN202111269062.9A priority Critical patent/CN114122413A/en
Publication of CN114122413A publication Critical patent/CN114122413A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/8605—Porous electrodes
    • H01M4/861—Porous electrodes with a gradient in the porosity
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/88—Processes of manufacture
    • H01M4/8825—Methods for deposition of the catalytic active composition
    • H01M4/8828—Coating with slurry or ink
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/90—Selection of catalytic material
    • H01M4/92—Metals of platinum group
    • H01M4/921—Alloys or mixtures with metallic elements
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/90—Selection of catalytic material
    • H01M4/92—Metals of platinum group
    • H01M4/925—Metals of platinum group supported on carriers, e.g. powder carriers
    • H01M4/926—Metals of platinum group supported on carriers, e.g. powder carriers on carbon or graphite
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/10—Fuel cells with solid electrolytes
    • H01M8/1004—Fuel cells with solid electrolytes characterised by membrane-electrode assemblies [MEA]
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/50—Fuel cells

Abstract

The invention relates to a membrane electrode catalyst layer with a gradient pore structure and a preparation method and application thereof, wherein the catalyst layer comprises a macroporous layer (11), a microporous layer (12) and a noble metal catalyst, and the microporous layer (12) is close to one side of a proton exchange membrane (2); the noble metal catalyst comprises a large catalyst and a small catalyst; the macroporous layer (11) comprises a macroporous catalyst; the small pore layer (12) comprises a small catalyst. At least one transition layer is arranged between the macroporous layer (11) and the microporous layer (12), and the transition layer comprises a large catalyst and a small catalyst. The transition layer is provided with a plurality of layers, and the mass fraction of the large catalyst in each transition layer gradually decreases from layer to layer along the direction from the large-pore layer (11) to the small-pore layer (12). Compared with the prior art, the invention has the advantages of ensuring the wetting of the catalyst layer and the proton conduction capability in the catalyst layer, high battery performance and the like.

Description

Membrane electrode catalyst layer with gradient pore structure and preparation method and application thereof
Technical Field
The invention relates to the field of membrane electrode catalyst layers, in particular to a membrane electrode catalyst layer with a gradient pore structure and a preparation method and application thereof.
Background
The membrane electrode is used as a core component of a fuel cell, mainly comprises a proton exchange membrane, a catalyst layer and a diffusion layer, wherein the catalyst layer is used as a place for chemical reaction of fuel in the membrane electrode, and the optimization of the structure and the improvement of the performance of the membrane electrode are always the key points of research. The catalytic layer is typically composed of Pt particles, a carbon support that conducts electrons, an ionomer that conducts protons and binding action (typically Nafion solution), and a large number of pores.
The pore structure within the catalytic layer is an important parameter in determining gas transport and water management. The catalyst layer can be divided into a primary pore and a secondary pore, wherein the primary pore is mainly formed by mutually gathering a plurality of carbon carriers, the radius of the pore formed in the catalyst layer is about 2-20 nm, the secondary pore is mainly formed by mutually gathering a plurality of carbon carriers into large particles, and the radius of the pores formed among the carbon carriers is generally more than 20 nm. In the traditional CCM preparation method, under the influence of a plurality of factors such as preparation materials, a hot pressing process and the like, the porosity inside the catalyst layer is low, the pore diameter is small, and a certain diffusion resistance is formed on reactant gas. In order to improve the power generation efficiency of the cell, accelerate the electrochemical reaction process and improve the output current density, the problems of mass transfer and water management of the fuel cell under high current density also need to be solved. Therefore, optimizing the pore size distribution and pore size of the catalytic layer is critical in the preparation of membrane electrodes. For the CCM preparation process, the optimization of the pore structure of the catalyst layer needs to be started from the preparation materials of the catalyst layer, carbon carriers, such as Ketjen Black and Vulcan XC-72, the pore diameter distribution of the carbon carriers is similar, but the proportion of the specific surface area to the pore size is different, carbon carriers, ionomers and solvents all have influence on the pores of the catalyst layer; the addition of the ionomer increases the electrochemical reaction active region of the catalyst layer, effectively conducts protons and improves the utilization rate of the catalyst, but the catalyst layer contains too much ionomer, which not only covers a large amount of Pt/C particles and hinders electron conduction, but also can block 'primary holes' and 'secondary holes' in the catalyst layer, so that the transmission channel of internal water and reaction gas is hindered, and thus the performance of the battery is greatly weakened; the solvent mainly acts to disperse the catalytic layer material and promote the formation of a pore structure, which is related to its properties such as viscosity, solubility, volatility, dielectric constant, etc.
The current common membrane electrode is often under the condition of large current density (>1A/cm2) Serious mass transfer polarization appears, and the water that the reaction generated can not in time be discharged and lead to the water logging, has not only covered the reaction site of catalyst, has also prevented the entering of reaction gas, and for solving this problem, it is very important to optimize the aperture distribution of catalysis layer, and this patent has designed a catalysis layer that has gradient pore structure, can effectively alleviate the water logging, promotes the output voltage of battery.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a membrane electrode catalyst layer with a gradient pore structure, a preparation method and application thereof, wherein the membrane electrode catalyst layer ensures the wetting of the catalyst layer and the proton conduction capability in the catalyst layer and has high cell performance.
The purpose of the invention can be realized by the following technical scheme:
the inventor knows that the composition and structure of the catalyst layers on both sides of the proton exchange membrane of the membrane electrode serving as the core component of the hydrogen fuel cell play a decisive role in the performance of the cell, the catalyst layers are the places where electrochemical reactions occur, and the membrane electrode needs to have good proton conductivity and electrical conductivity, and in addition, the membrane electrode also needs to be capable of timely discharging water generated by the reactions so as to prevent reaction gas from contacting with active sites and reduce mass transfer resistance.
The invention selects noble metal catalysts of carbon carriers with different diameters to prepare the catalyst layer with gradient pore size, wherein the catalyst layer closest to the proton exchange membrane becomes a pore layer, the catalyst layer furthest away from the proton exchange membrane is called a macroporous layer, and a transition layer with large pores and small pores arranged alternately can be continuously arranged between the pore layer and the macroporous layer. Catalyst layers with different layers and thicknesses are obtained by controlling a preparation process so as to achieve the purpose of improving the performance of the battery, and the specific scheme is as follows:
a membrane electrode catalyst layer with a gradient pore structure comprises a macroporous layer, a small pore layer and a noble metal catalyst, wherein the small pore layer is close to one side of a proton exchange membrane; the noble metal catalyst comprises a large catalyst and a small catalyst;
the macroporous layer comprises a large catalyst; the small pore layer comprises a small catalyst.
Furthermore, at least one transition layer is arranged between the macroporous layer and the microporous layer, and the transition layer comprises a large catalyst and a small catalyst.
Furthermore, the transition layer is provided with a plurality of layers, and the mass fraction of the large catalyst in each transition layer is gradually reduced from layer to layer along the direction from the large pore layer to the small pore layer.
Further, the noble metal catalyst comprises a carbon carrier and noble metal loaded on the carbon carrier, the diameter of the carbon carrier is 30-200nm, the diameter of the noble metal nano-particles is 2-10nm, and the loading amount of the noble metal nano-particles is 30-60%.
Further, the large catalyst comprises a large carbon carrier and noble metal nano-particles; the diameter of the large carbon carrier is 100-200 nm; the small catalyst comprises a small carbon carrier and noble metal nano-particles; the diameter of the small carbon carrier is 30-100nm, and is not 100.
A method for preparing a membrane electrode catalyst layer having a gradient pore structure as described above, comprising the steps of:
preparing small-pore layer catalyst layer slurry: uniformly mixing a small catalyst, a perfluorinated sulfonic acid resin solution, a low-boiling-point solvent and deionized water to obtain small-pore layer catalyst layer slurry;
preparing slurry of the transition layer catalyst layer: uniformly mixing a small catalyst, a large catalyst, a perfluorinated sulfonic acid resin solution, a low-boiling-point solvent and deionized water to obtain transition layer catalyst layer slurry;
preparing slurry of the macroporous catalyst layer: uniformly mixing a large catalyst, a perfluorinated sulfonic acid resin solution, a low-boiling-point solvent and deionized water to obtain a macroporous catalyst layer slurry;
firstly, transferring the prepared small-pore layer catalyst layer slurry to one side of a proton exchange membrane by adopting a spraying method, then spraying transition layer catalyst layer slurry on the small-pore layer catalyst layer slurry, and then spraying large-pore layer catalyst layer slurry on the transition layer catalyst layer slurry;
and repeating the previous step on the other side of the proton exchange membrane to obtain the membrane electrode catalyst layer with the gradient pore structure.
If there is no transition layer, the preparation steps can be summarized as:
preparing small-pore layer catalyst layer slurry: uniformly mixing a small catalyst, a perfluorinated sulfonic acid resin solution, a low-boiling-point solvent and deionized water to obtain small-pore layer catalyst layer slurry;
preparing slurry of the macroporous catalyst layer: uniformly mixing a large catalyst, a perfluorinated sulfonic acid resin solution, a low-boiling-point solvent and deionized water to obtain a macroporous catalyst layer slurry;
firstly, transferring the prepared small-pore layer catalyst layer slurry to one side of a proton exchange membrane by a spraying method, and then spraying the large-pore layer catalyst layer slurry on the small-pore layer catalyst layer slurry;
and repeating the previous step on the other side of the proton exchange membrane to obtain the membrane electrode catalyst layer with the gradient pore structure.
Further, in the catalyst layer slurry, the mass ratio of the perfluorosulfonic acid resin solid to the total carbon component in the noble metal catalyst is 0.5-1.5, and the mass ratio of the low-boiling-point solvent to the deionized water is (5-20): 1; the solid content in the catalyst slurry is 0.5-20 wt%.
In the concrete slurry, the mass ratio of the perfluorosulfonic acid resin solid to the total carbon component in each noble metal catalyst is 0.5-1.5, for example, in the small pore layer catalyst layer slurry, the mass ratio of the perfluorosulfonic acid resin solid to the total carbon component in the small catalyst is 0.5-1.5, and in the large pore layer catalyst layer slurry and the transition layer catalyst layer slurry, the mass ratio is similar.
Further, the equivalent mass EW of the perfluorosulfonic acid resin is 700-1100g/mol, and the boiling point of the low-boiling-point solvent is between 70 and 120 ℃, and specifically comprises ethanol, n-propanol or isopropanol.
Further, the surface temperature of the proton exchange membrane is kept between 70 and 120 ℃ during spraying.
Furthermore, in the transition layer catalyst layer slurry, the mass of the large catalyst accounts for 10-90% of the mass of the transition layer, and the mass of the small catalyst accounts for 10-90% of the mass of the transition layer.
Use of a membrane electrode catalyst layer having a gradient pore structure as described above for use in a fuel cell.
Compared with the prior art, the invention has the following advantages:
(1) according to the invention, different pore diameter gradients are arranged in the catalyst layer, so that water generated by reaction can be smoothly discharged without losing too fast, and the wetting of the catalyst layer and the proton conduction capability in the catalyst layer are ensured;
(2) according to the invention, different pore diameter gradients are arranged in the catalyst layer, so that the reaction gas can smoothly reach the active site without too high flow speed, thereby ensuring that the water content in the catalyst layer is proper and the proton exchange membrane is not dried;
(3) the transition layer is arranged in the catalyst layer, so that the concentration of the product water and the reaction gas in the catalyst layer is distributed in a gradient manner, and the condition that each part of the catalyst layer is flooded with water or is short of gas is avoided;
(4) the invention uses the noble metal catalyst with larger carbon carrier particle size, thereby reducing the synthesis difficulty of the catalyst and reducing the cost of the membrane electrode while ensuring the performance.
Drawings
FIG. 1 is a schematic view showing a catalytic layer structure of a membrane electrode according to example 1;
FIG. 2 is a schematic view showing a catalytic layer structure of a membrane electrode according to example 2;
FIG. 3 is a schematic view showing a catalytic layer structure of a membrane electrode according to example 3;
FIG. 4 is a schematic view showing a catalytic layer structure of a membrane electrode assembly of a comparative example;
FIG. 5 is an electrochemical voltammogram in a gradient distribution when the pore size of the catalytic layer is uniformly distributed;
the reference numbers in the figures indicate: common microporous layer 1, macroporous layer 11, first transition layer 111, second transition layer 112, microporous layer 12 and proton exchange membrane 2.
Detailed Description
The invention is described in detail below with reference to the figures and specific embodiments. The present embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation manner and a specific operation process are given, but the protection scope of the present invention is not limited to the following embodiments.
A membrane electrode catalyst layer with a gradient pore structure comprises a macroporous layer 11, a small pore layer 12 and a noble metal catalyst, wherein the small pore layer 12 is close to one side of a proton exchange membrane 2; the noble metal catalyst comprises a large catalyst and a small catalyst; the macroporous layer 11 comprises a macroporous catalyst; the small pore layer 12 includes a small catalyst therein.
At least one transition layer is arranged between the large-hole layer 11 and the small-hole layer 12, and the transition layer comprises a large catalyst and a small catalyst. Or the transition layer is provided with a plurality of layers, and the mass fraction of the large catalyst in each transition layer gradually decreases from layer to layer along the direction from the large hole layer 11 to the small hole layer 12.
The noble metal catalyst comprises a carbon carrier and noble metals (such as Pt, Pt-Pd, Pt-Ru and the like) loaded on the carbon carrier, wherein the diameter of the carbon carrier (solid carbon spheres, porous carbon or carbon nano tubes) is 30-200nm, the diameter of the noble metal nano particles is 2-10nm, and the loading capacity of the noble metal nano particles is 30-60%. The large catalyst comprises a large carbon carrier and noble metal nano-particles; the diameter of the large carbon carrier is 100-200 nm; the small catalyst comprises a small carbon carrier and noble metal nano-particles; the diameter of the small carbon carrier is 30-100nm, and is not 100.
The preparation method of the membrane electrode catalyst layer with the gradient pore structure comprises the following steps:
preparing small-pore layer catalyst layer slurry: uniformly mixing a small catalyst, a perfluorinated sulfonic acid resin solution, a low-boiling-point solvent and deionized water to obtain small-pore layer catalyst layer slurry;
preparing slurry of the transition layer catalyst layer: uniformly mixing a small catalyst, a large catalyst, a perfluorinated sulfonic acid resin solution, a low-boiling-point solvent and deionized water to obtain transition layer catalyst layer slurry; in the transition layer catalyst layer slurry, the mass of the large catalyst accounts for 10-90% of the mass of the transition layer, and the mass of the small catalyst accounts for 10-90% of the mass of the transition layer.
Preparing slurry of the macroporous catalyst layer: uniformly mixing a large catalyst, a perfluorinated sulfonic acid resin solution, a low-boiling-point solvent and deionized water to obtain a macroporous catalyst layer slurry;
firstly, transferring the prepared small-pore layer catalyst layer slurry to one side of a proton exchange membrane 2 by adopting a spraying method, then spraying transition layer catalyst layer slurry on the small-pore layer catalyst layer slurry, and then spraying large-pore layer catalyst layer slurry on the transition layer catalyst layer slurry;
and repeating the previous step on the other side of the proton exchange membrane 2 to obtain the membrane electrode catalyst layer with the gradient pore structure. When spraying, the surface temperature of the proton exchange membrane 2 is kept between 70 ℃ and 120 ℃.
In the catalyst layer slurry, the mass ratio of the perfluorosulfonic acid resin solid to the total carbon component in the noble metal catalyst is 0.5-1.5, and the mass ratio of the low-boiling-point solvent to the deionized water is (5-20): 1; the solid content in the catalyst slurry is 0.5-20 wt%. The equivalent mass EW of the perfluorosulfonic acid resin is 700-1100g/mol, and the boiling point of the low-boiling-point solvent is between 70 and 120 ℃, and specifically comprises ethanol, n-propanol or isopropanol.
Example 1
The preparation method of the catalyst layer with a large and small layer pore structure comprises the following steps:
a: preparing small-pore layer catalyst layer slurry: uniformly mixing a noble metal catalyst, a perfluorinated sulfonic acid resin solution, a low-boiling-point solvent and deionized water to obtain catalyst slurry; wherein the diameter of the carbon carrier of the noble metal catalyst is 30-100nm, the mass ratio of the mass of the perfluorosulfonic acid resin solid to the total mass of the carbon components in the noble metal catalyst is 0.7, the diameter of the carrier of the noble metal catalyst is 2-10nm, the loading amount of the noble metal Pt nano particles is 50%, and the mass ratio of the low-boiling-point solvent to the deionized water is 10; the solids content in the catalyst slurry was 1%;
b: preparing slurry of the macroporous catalyst layer: uniformly mixing a noble metal catalyst, a perfluorinated sulfonic acid resin solution, a low-boiling-point solvent and deionized water to obtain catalyst slurry; wherein the diameter of the carbon carrier of the noble metal catalyst is 100-200nm, the mass ratio of the mass of the perfluorosulfonic acid resin solid to the mass of the total carbon component in the noble metal catalyst is 0.7, the diameter of the carrier of the noble metal catalyst is between 2 and 10nm, and the loading amount of the noble metal Pt nano particles is 50 percent; the mass ratio of the low-boiling point solvent to the deionized water is 10; the solids content in the catalyst slurry was 1%;
c: transferring the prepared small-pore layer catalyst layer slurry to one side of a proton exchange membrane by a spraying method, and spraying the large-pore layer catalyst layer slurry on the small-pore layer catalyst layer slurry, wherein the surface temperature of the proton exchange membrane is controlled to be 70-120 ℃.
d: and c, repeating the step c on the other side of the proton exchange membrane after spraying one side of the proton exchange membrane, wherein the finished product is shown in figure 1.
Example 2
The preparation method of the catalyst layer with the three-layer pore structure of the macroporous layer, the single-layer transition layer and the small-pore layer comprises the following steps:
a: preparing small-pore layer catalyst layer slurry, namely uniformly mixing a noble metal catalyst, a perfluorinated sulfonic acid resin solution, a low-boiling-point solvent and deionized water to obtain catalyst slurry; wherein the diameter of the carbon carrier of the noble metal catalyst is 30-100nm, the mass ratio of the mass of the perfluorosulfonic acid resin solid to the mass of the total carbon component in the noble metal catalyst is 0.7, the diameter of the carrier of the noble metal catalyst is 2-10nm, and the loading capacity of the noble metal Pt nano-particles is 50%; the mass ratio of the low-boiling point solvent to the deionized water is 10; the solids content in the catalyst slurry was 1%;
b: preparing transition layer catalyst layer slurry, namely uniformly mixing a noble metal catalyst, a perfluorinated sulfonic acid resin solution, a low-boiling-point solvent and deionized water to obtain catalyst slurry; wherein the large catalyst accounts for 50% of the mass of the transition layer, and the small catalyst accounts for 50% of the mass of the transition layer; the ratio of the mass of the perfluorosulfonic acid resin solid to the mass of the total carbon component in the noble metal catalyst was 0.7; the diameter of the carrier of the noble metal catalyst is between 2 and 10nm, and the loading amount of the noble metal Pt nano particles is 50 percent;
c: preparing macroporous catalyst layer slurry, namely uniformly mixing a noble metal catalyst, a perfluorinated sulfonic acid resin solution, a low-boiling-point solvent and deionized water to obtain catalyst slurry; wherein the diameter of the carbon carrier of the noble metal catalyst is 100-200nm, the mass ratio of the mass of the perfluorosulfonic acid resin solid to the mass of the total carbon component in the noble metal catalyst is 0.7, the diameter of the carrier of the noble metal catalyst is between 2 and 10nm, and the loading amount of the noble metal Pt nano particles is 50 percent; the mass ratio of the low-boiling point solvent to the deionized water is 10; the solids content in the catalyst slurry was 1%;
d: transferring the prepared small-pore layer catalyst layer slurry to one side of a proton exchange membrane by a spraying method, and then spraying transition layer and large-pore layer catalyst layer slurry on the small-pore layer catalyst layer slurry in sequence, wherein the surface temperature of the proton exchange membrane is controlled to be 70-120 ℃.
e: and d, repeating the step d on the other side of the proton exchange membrane after spraying one side of the proton exchange membrane, wherein the finished product is shown in figure 2.
Example 3
The preparation method of the catalyst layer with the three-layer pore structure of the macroporous layer, the two transition layers and the small pore layer comprises the following steps:
a: preparing small-pore layer catalyst layer slurry, namely uniformly mixing a noble metal catalyst, a perfluorinated sulfonic acid resin solution, a low-boiling-point solvent and deionized water to obtain catalyst slurry; wherein the diameter of the carbon carrier of the noble metal catalyst is 30-100nm, the mass ratio of the mass of the perfluorosulfonic acid resin solid to the mass of the total carbon component in the noble metal catalyst is 0.7, the diameter of the carrier of the noble metal catalyst is 2-10nm, and the loading capacity of the noble metal Pt nano-particles is 50%; the mass ratio of the low-boiling point solvent to the deionized water is 10; the solids content in the catalyst slurry was 10%;
b: preparing slurry of a first transition layer catalyst layer, namely uniformly mixing a noble metal catalyst, a perfluorinated sulfonic acid resin solution, a low-boiling-point solvent and deionized water to obtain catalyst slurry; wherein the mass of the large catalyst accounts for 30 percent of the mass of the transition layer, the mass of the small catalyst accounts for 70 percent of the mass of the transition layer, and the mass ratio of the mass of the perfluorosulfonic acid resin solid to the mass of the total carbon component in the noble metal catalyst is 0.7; the diameter of the carrier of the noble metal catalyst is between 2 and 10nm, and the loading amount of the noble metal Pt nano particles is 50 percent
c: preparing slurry of a catalyst layer of a second transition layer, namely uniformly mixing a noble metal catalyst, a perfluorinated sulfonic acid resin solution, a low-boiling-point solvent and deionized water to obtain catalyst slurry; wherein the mass of the large catalyst accounts for 70 percent of the mass of the transition layer, the mass of the small catalyst accounts for 30 percent of the mass of the transition layer, and the mass ratio of the mass of the perfluorosulfonic acid resin solid to the mass of the total carbon component in the noble metal catalyst is 0.7; the diameter of the carrier of the noble metal catalyst is between 2 and 10nm, and the loading amount of the noble metal Pt nano particles is 50 percent
d: preparing macroporous catalyst layer slurry, namely uniformly mixing a noble metal catalyst, a perfluorinated sulfonic acid resin solution, a low-boiling-point solvent and deionized water to obtain catalyst slurry; wherein the diameter of the noble metal catalyst carbon carrier is 100-200nm, and the mass ratio of the mass of the perfluorosulfonic acid resin solid to the mass of the total carbon component in the noble metal catalyst is 0.7; the diameter of the carrier of the noble metal catalyst is between 2 and 10nm, and the loading amount of the noble metal Pt nano particles is 50 percent; the mass ratio of the low-boiling point solvent to the deionized water is 10; the solids content in the catalyst slurry was 1%;
e: transferring the prepared small-pore layer catalyst layer slurry to one side of a proton exchange membrane by a spraying method, and spraying a first layer catalyst layer slurry, a second layer catalyst layer slurry and a large-pore layer catalyst layer slurry on the small-pore layer catalyst layer slurry, wherein the surface temperature of the proton exchange membrane is controlled to be 70-120 ℃.
f: and e, repeating the step e on the other side of the proton exchange membrane after spraying one side of the proton exchange membrane, wherein the finished product is shown in figure 3.
Comparative example
The preparation method of the common catalytic layer comprises the following steps:
a: uniformly mixing a noble metal catalyst, a perfluorinated sulfonic acid resin solution, a low-boiling-point solvent and deionized water to obtain catalyst slurry; wherein the diameter of the carbon carrier of the noble metal catalyst is 30-200nm, the mass ratio of the mass of the perfluorosulfonic acid resin solid to the mass of the total carbon component in the noble metal catalyst is 0.7, the diameter of the carrier of the noble metal catalyst is 2-10nm, and the loading capacity of the noble metal Pt nano-particles is 50%; the mass ratio of the low-boiling point solvent to the deionized water is 10; the solids content in the catalyst slurry was 1%;
b: transferring the prepared catalyst layer slurry to one side of a proton exchange membrane by a spraying method, and controlling the surface temperature of the proton exchange membrane to be between 70 and 120 ℃.
c: and (c) after spraying one side of the proton exchange membrane, repeating the step (b) on the other side of the proton exchange membrane, and obtaining a finished product as shown in figure 4.
Fig. 1-3 are schematic diagrams of the membrane electrode catalyst layer with the gradient pore structure provided by the invention. The pore diameter of the catalytic layer gradually increases from the proton exchange membrane to the diffusion layer. The effective reaction area of the membrane electrode used in all the examples was 30cm2。
Fig. 5 is an electrochemical voltammogram in a gradient distribution when the pore size of the catalytic layer is uniformly distributed. The operating conditions at the time of battery testing were: hydrogen relative humidity 40%, air relative humidity 30%, cell temperature 70 ℃, hydrogen/air stoichiometric ratio 1.5/1.8, operating pressure 100 kPa.
As can be seen from the results of cell polarization tests, the output voltage of the cells in the examples was significantly increased compared to the comparative examples after introducing the gradient pore structure into the catalytic layer, while the output voltage of the cells in the examples was 1A/cm2The voltage difference before is small because the mass transfer polarization is not too serious at this time, the effect of the gradient pore structure is not fully shown, the product water is continuously increased along with the gradual increase of the current density, and the higher requirement is provided for the water drainage effect of the catalyst layer, the embodiment 3 has the advantages that the advantage is larger and larger, and the trend of the voltage reduction is obviously slower than that of other embodiments along with the increase of the current density, which also shows that the pore structure with gradient distribution is introduced into the catalyst layer, and the effect of inhibiting the rapid voltage reduction caused by the mass transfer polarization in the case of large current density is obvious.
TABLE 1
Figure BDA0003328017920000101
Table 1 shows the electrochemical active area of the catalytic layer at the pore size gradient distribution measured on-line after the sample was fabricated into MEA. The scanning speed is set to be 20mV/s, and the platinum loading capacity of the anode is 0.1mg/cm2Cathode platinum loading 0.3mg/cm2Relative humidity 100%, cell temperature 70 ℃.
The foregoing is directed to preferred embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. However, any simple modification, equivalent change and modification of the above embodiments according to the technical essence of the present invention are within the protection scope of the technical solution of the present invention.

Claims (10)

1. The membrane electrode catalyst layer with the gradient pore structure is characterized by comprising a macroporous layer (11), a microporous layer (12) and a noble metal catalyst, wherein the microporous layer (12) is close to one side of a proton exchange membrane (2); the noble metal catalyst comprises a large catalyst and a small catalyst;
the macroporous layer (11) comprises a macroporous catalyst; the small pore layer (12) comprises a small catalyst.
2. The membrane electrode catalyst layer with the gradient pore structure according to claim 1, wherein at least one transition layer is further arranged between the macroporous layer (11) and the small pore layer (12), and the transition layer comprises a large catalyst and a small catalyst.
3. The membrane electrode catalyst layer with a gradient pore structure according to claim 2, wherein the transition layers are provided with a plurality of layers, and the mass fraction of the large catalyst in each transition layer decreases from layer to layer along the direction from the large pore layer (11) to the small pore layer (12).
4. The membrane electrode catalyst layer with a gradient pore structure according to any one of claims 1 to 3, wherein the noble metal catalyst comprises a carbon support and noble metal nanoparticles supported on the carbon support, the diameter of the carbon support is 30 to 200nm, the diameter of the noble metal nanoparticles is 2 to 10nm, and the supporting amount of the noble metal nanoparticles is 30 to 60%.
5. The membrane electrode catalyst layer having a gradient pore structure according to claim 1, wherein the large catalyst comprises a large carbon support and noble metal nanoparticles; the diameter of the large carbon carrier is 100-200 nm; the small catalyst comprises a small carbon carrier and noble metal nano-particles; the diameter of the small carbon carrier is 30-100 nm.
6. A method for preparing a membrane electrode catalyst layer with a gradient pore structure according to any one of claims 1 to 5, which comprises the steps of:
preparing small-pore layer catalyst layer slurry: uniformly mixing a small catalyst, perfluorinated sulfonic acid resin, a low-boiling-point solvent and deionized water to obtain small-pore layer catalyst layer slurry;
preparing slurry of the transition layer catalyst layer: uniformly mixing a small catalyst, a large catalyst, perfluorinated sulfonic acid resin, a low-boiling-point solvent and deionized water to obtain transition layer catalyst layer slurry;
preparing slurry of the macroporous catalyst layer: uniformly mixing a large catalyst, perfluorinated sulfonic acid resin, a low-boiling point solvent and deionized water to obtain a macroporous catalyst layer slurry;
firstly, transferring the prepared small-pore layer catalyst layer slurry to one side of a proton exchange membrane (2) by adopting a spraying method, then spraying transition layer catalyst layer slurry on the small-pore layer catalyst layer slurry, and then spraying large-pore layer catalyst layer slurry on the transition layer catalyst layer slurry;
and repeating the previous step on the other side of the proton exchange membrane (2) to obtain the membrane electrode catalyst layer with the gradient pore structure.
7. The preparation method of the membrane electrode catalyst layer with the gradient pore structure according to claim 6, wherein in the catalyst layer slurry, the mass ratio of the perfluorosulfonic acid resin solid to the total carbon component in the noble metal catalyst is 0.5-1.5, and the mass ratio of the low-boiling-point solvent to the deionized water is (5-20): 1; the solid content in the catalyst slurry is 0.5-20 wt%.
8. The method for preparing a membrane electrode catalyst layer with a gradient pore structure as claimed in claim 6, wherein the equivalent mass EW of the perfluorosulfonic acid resin is 700-1100g/mol, and the boiling point of the low boiling point solvent is between 70-120 ℃, specifically comprising ethanol, n-propanol or isopropanol; when spraying, the surface temperature of the proton exchange membrane (2) is kept between 70 ℃ and 120 ℃.
9. The preparation method of the membrane electrode catalyst layer with the gradient pore structure according to claim 6, wherein in the slurry of the transition layer catalyst layer, the mass of the large catalyst accounts for 10-90% of the mass of the transition layer, and the mass of the small catalyst accounts for 10-90% of the mass of the transition layer.
10. Use of a membrane electrode catalyst layer with a gradient pore structure according to any one of claims 1 to 5 in a fuel cell.
CN202111269062.9A 2021-10-29 2021-10-29 Membrane electrode catalyst layer with gradient pore structure and preparation method and application thereof Pending CN114122413A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202111269062.9A CN114122413A (en) 2021-10-29 2021-10-29 Membrane electrode catalyst layer with gradient pore structure and preparation method and application thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111269062.9A CN114122413A (en) 2021-10-29 2021-10-29 Membrane electrode catalyst layer with gradient pore structure and preparation method and application thereof

Publications (1)

Publication Number Publication Date
CN114122413A true CN114122413A (en) 2022-03-01

Family

ID=80379383

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111269062.9A Pending CN114122413A (en) 2021-10-29 2021-10-29 Membrane electrode catalyst layer with gradient pore structure and preparation method and application thereof

Country Status (1)

Country Link
CN (1) CN114122413A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116364948A (en) * 2023-03-24 2023-06-30 一汽解放汽车有限公司 Pore-diameter gradient cathode catalytic layer and preparation method and application thereof

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1691383A (en) * 2004-04-26 2005-11-02 株式会社东芝 Anode for liquid fuel cell, membrane electrode assembly for liquid fuel cell, and liquid fuel cell
US20080206616A1 (en) * 2007-02-27 2008-08-28 Cabot Corporation Catalyst coated membranes and sprayable inks and processes for forming same
CN102315457A (en) * 2011-08-03 2012-01-11 哈尔滨工业大学 Passive miniature methanol fuel cell membrane electrode and its preparation method
US20160156054A1 (en) * 2014-11-28 2016-06-02 Ford Motor Company Membrane electrode assembly for a fuel cell, method for preparing the membrane electrode assembly, fuel cell system and vehicle
CN106684395A (en) * 2016-11-22 2017-05-17 新源动力股份有限公司 Technique for manufacturing cathode catalyst layer with gradient porosity for fuel cell
CN110880604A (en) * 2018-09-05 2020-03-13 广州汽车集团股份有限公司 Proton exchange membrane fuel cell membrane electrode and preparation method thereof
CN111463442A (en) * 2020-04-13 2020-07-28 上海电气集团股份有限公司 Catalyst layer, fuel cell membrane electrode and preparation method thereof
CN112103543A (en) * 2020-10-16 2020-12-18 大连理工大学 Gradient membrane electrode for proton exchange membrane fuel cell and preparation method thereof
CN112259768A (en) * 2020-10-21 2021-01-22 成都新柯力化工科技有限公司 Fuel cell membrane electrode with gradient distribution catalyst layer and preparation method thereof

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1691383A (en) * 2004-04-26 2005-11-02 株式会社东芝 Anode for liquid fuel cell, membrane electrode assembly for liquid fuel cell, and liquid fuel cell
US20080206616A1 (en) * 2007-02-27 2008-08-28 Cabot Corporation Catalyst coated membranes and sprayable inks and processes for forming same
CN102315457A (en) * 2011-08-03 2012-01-11 哈尔滨工业大学 Passive miniature methanol fuel cell membrane electrode and its preparation method
US20160156054A1 (en) * 2014-11-28 2016-06-02 Ford Motor Company Membrane electrode assembly for a fuel cell, method for preparing the membrane electrode assembly, fuel cell system and vehicle
CN106684395A (en) * 2016-11-22 2017-05-17 新源动力股份有限公司 Technique for manufacturing cathode catalyst layer with gradient porosity for fuel cell
CN110880604A (en) * 2018-09-05 2020-03-13 广州汽车集团股份有限公司 Proton exchange membrane fuel cell membrane electrode and preparation method thereof
CN111463442A (en) * 2020-04-13 2020-07-28 上海电气集团股份有限公司 Catalyst layer, fuel cell membrane electrode and preparation method thereof
CN112103543A (en) * 2020-10-16 2020-12-18 大连理工大学 Gradient membrane electrode for proton exchange membrane fuel cell and preparation method thereof
CN112259768A (en) * 2020-10-21 2021-01-22 成都新柯力化工科技有限公司 Fuel cell membrane electrode with gradient distribution catalyst layer and preparation method thereof

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116364948A (en) * 2023-03-24 2023-06-30 一汽解放汽车有限公司 Pore-diameter gradient cathode catalytic layer and preparation method and application thereof

Similar Documents

Publication Publication Date Title
JP4465058B2 (en) Membrane-electrode unit for polymer-electrolyte fuel cells, process for producing the same and ink for manufacturing membrane-electrode unit
CN105228741B (en) Catalyst, and electrode catalyst layer, membrane electrode assembly, and fuel cell using same
CN101557001B (en) Fuel cell film electrode and preparation method thereof
EP2722916A1 (en) Gas diffusion layer for fuel cell
CN112993270A (en) Catalyst, and electrode catalyst layer, membrane electrode assembly, and fuel cell using same
CN111092230A (en) Catalyst slurry of proton exchange membrane fuel cell and application thereof
CN111146482A (en) Self-humidifying proton exchange membrane and preparation method and application thereof
US20220216484A1 (en) Cathode catalyst layer structure for enhancing durability of catalyst and fabrication method thereof
WO2007005081A2 (en) Voltage cycling durable catalysts
US20190280307A1 (en) Composite electrode layer for polymer electrolyte fuel cell
CN114171748A (en) Fuel cell catalyst slurry for forming ionomer network and preparation method thereof
CN110797546B (en) Microporous layer structure, preparation method, membrane electrode assembly and fuel cell
Li et al. Highly ordered 3D macroporous scaffold supported Pt/C oxygen electrodes with superior gas-proton transportation properties and activities for fuel cells
CN114122413A (en) Membrane electrode catalyst layer with gradient pore structure and preparation method and application thereof
Cai et al. One simple method to improve the mass transfer of membrane electrode assembly to realize operation under wide humidity
Kim et al. Effects of heat treatment time on electrochemical properties and electrode structure of polytetrafluoroethylene-bonded membrane electrode assemblies for polybenzimidazole-based high-temperature proton exchange membrane fuel cells
CN112615018A (en) Cathode catalyst layer, preparation method thereof, membrane electrode and fuel cell
KR101101497B1 (en) Producing method for electrodes of fuel cell with high temperature type and membrane electrode assembly produced thereby
CN114566653B (en) Non-uniform catalyst layer, membrane electrode and preparation method thereof
CN100506373C (en) Improved pemfc electrocatalyst based on mixed carbon supports
US20070190398A1 (en) Electrode for fuel cell, fuel cell, and method of preparing electrode for fuel cell
KR102075180B1 (en) Membrane electrode assembly and fuel cell comprising the same
JP2020057516A (en) Electrode layer, membrane electrode assembly including the electrode layer, and fuel cell
CN115101754A (en) Preparation method of graphene aerogel based gas diffusion electrode of direct methanol fuel cell and membrane electrode
CN114023977A (en) Membrane electrode with ionic resin in continuous gradient distribution and preparation method thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination