Nano composite material based on porous carrier as well as preparation method and application of nano composite material

Abstract

The invention discloses a nano composite material based on a porous carrier as well as a preparation method and application of the nano composite material. The nano composite material comprises a porous carrier and nano particles loaded by the porous carrier, the porous carrier is provided with mesopores and other pore channels except the mesopores, and the nano particles are mainly loaded in the mesopores; the nano-particles comprise a metal and a metal compound, the nano-composite material further comprises doping elements, and part of the doping elements are used for forming the metal compound. When being used as a catalyst, the nano composite material has the advantages of high catalytic activity, good high-temperature operation stability and the like, and the preparation method of the nano composite material can realize directional controllable adjustment of loading sites of nano particles on a porous carrier.

Description

Technical Field

[0001] The invention relates to a nano composite material, in particular to a nano composite material based on a porous carrier and a preparation method and application thereof, belonging to the field of material science. Background Art

[0002] Nanocomposites based on porous carriers have shown broad application potential in many fields such as clean energy production, environment and energy conversion, chemical energy storage, wearable and implantable bioelectronic devices due to their unique structural advantages such as high specific surface area, adjustable pore size, excellent conductivity and mechanical adaptability. Especially in the field of high-temperature fuel cells, the development of catalyst materials with high activity and high stability is of great significance.

[0003] For nanocomposites based on porous carriers, the loading sites of active nanoparticles are of great significance. Taking platinum-based catalysts as an example, the proportion of platinum particles in the mesopores of porous carriers has an important influence on their catalytic activity and anti-poisoning performance, but the existing technology cannot controllably adjust the proportion of platinum particles in the mesopores of porous carriers. Specifically, the common synthesis processes of platinum-based catalysts currently include polyol method, ion exchange method, colloid method, etc., but the surface tension of the reaction solvents used in these synthesis processes is too large, and the metal precursors cannot effectively infiltrate the mesopores. Platinum nanoparticles are mainly distributed in the pores outside the mesopores, resulting in direct contact between the nanoparticles and the poisoning substances, resulting in the inactivation of the active sites and affecting their catalytic performance. Some researchers have successfully loaded different proportions of nanoparticles on the inner and outer surfaces of Ketjen black carriers through different synthesis methods such as incipient wetness method and polyol reduction method. Among them, the catalyst nanoparticles prepared by the polyol method are mainly deposited on the outer surface of the Ketjen black carrier. At present, there is no report on the process that can achieve the controllable distribution of the proportion of mesoporous nanoparticles on the same carbon carrier.

[0004] In addition, existing platinum-based catalysts are generally only suitable for low-temperature proton exchange membrane fuel cell equipment with an operating temperature of less than 100°C. In order to further improve energy conversion efficiency, reduce hydrogen purity and reduce water management requirements, the high-temperature application of low-temperature proton exchange membrane fuel cell equipment has gradually become the most promising development direction in the future. However, the metal of existing platinum-based catalysts is easily dissolved and detached during high-temperature operation above 100°C, causing rapid performance degradation. Summary of the invention

[0005] The main purpose of the present invention is to provide a nanocomposite material based on a porous carrier and a preparation method and application thereof, so as to solve the above-mentioned problems in the prior art.

[0006] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention includes: The first aspect of the present invention provides a nanocomposite material based on a porous carrier, which comprises a porous carrier and nanoparticles supported by the porous carrier, and the nanocomposite material also satisfies the following conditions: (1.1) The porous carrier has mesopores and other pores other than the mesopores, wherein the volume proportion of the mesopores is 50% to 90%; (1.2) The nanoparticles are loaded in the mesopores and other pores outside the mesopores. The mass of the nanoparticles in the mesopores is defined as M, and the mass of the nanoparticles in other pores outside the mesopores is defined as N. Then Fx≥0.3, Fx=M / (M+N); (1.3) The nanoparticles comprise a metal and a metal compound, the mass ratio of the metal compound to the metal is 0.02 to 0.2, and the metal element in the metal compound is the same as at least part of the metal element in the metal; (1.4) The nanocomposite material further comprises a doping element, wherein a portion of the doping element is used to form the metal compound, and a mass ratio of the doping element to the metal element contained in the nanoparticles is 0.1 to 0.3.

[0007] The second aspect of the present invention provides a method for preparing a nanocomposite material based on a porous carrier, comprising: Allowing a liquid mixed reaction system comprising a metal source, an organic auxiliary agent and a solvent to fully react at room temperature to form a precursor liquid, wherein the molar ratio of the organic auxiliary agent to the metal source is 1:3 to 1:1, and the organic auxiliary agent comprises a doping element; The porous carrier is dispersed in the precursor liquid and fully mixed and reacted at room temperature, and then the obtained reaction product is dried and reduced in sequence, and then directly etched after the reduction treatment, so as to obtain the nanocomposite material based on the porous carrier.

[0008] The third aspect of the present invention provides use of the porous support-based nanocomposite material in preparing a fuel cell catalyst or a fuel cell.

[0009] A fourth aspect of the present invention provides a fuel cell catalyst, which comprises the aforementioned porous support-based nanocomposite material.

[0010] A fifth aspect of the present invention provides a fuel cell comprising the aforementioned fuel cell catalyst.

[0011] Compared with the prior art, the present invention has at least the following beneficial effects: First, in the nanocomposite material based on a porous carrier provided by the present invention, the nanoparticles as the active material can be controllably enriched in the mesopores of the porous carrier, that is, the controllable loading of the nanoparticles on the porous carrier is achieved, so that when the nanocomposite material is used as a catalyst, it has the advantages of controllable catalytic performance, high mass activity, not easy to be poisoned, and high cycle stability; at the same time, doping elements are also introduced into the nanocomposite material. The metal compounds formed by the combination of these doping elements and some metal elements in the nanoparticles can cooperate with the metals in the nanoparticles to form a synergistic catalytic system, improve the metal electron cloud structure, and further significantly enhance the activity of the nanocomposite material as a catalyst and the stability under high-temperature operating conditions. Exemplarily, a nanocomposite material based on a porous carrier provided by the present invention is a platinum-based catalyst, and its mass activity can be as high as 720 mA / mg Pt (0.9 V vs. RHE), the performance decay rate after 30,000 cycles is less than 10%. During high-temperature operation above 105°C, the membrane electrode peak power can reach 1.55W / cm 2 It meets the high-temperature application requirements of low-temperature proton exchange membrane fuel cells, caters to the development of new proton exchange membrane fuel cells in the future, and can provide strong support for the commercial application of proton exchange membrane fuel cells.

[0012] Secondly, in the synthesis process of nanocomposite materials based on porous carriers provided by the present invention, by adding organic additives to the raw material system, on the one hand, the charge on the surface of the porous carrier can be regulated to achieve the enrichment and regulation of metal colloid particles as precursors of nanoparticles, so that the nanoparticles can be controllably loaded on the porous carrier; on the other hand, the doping elements introduced by the organic additives are combined with part of the metal elements used to constitute the nanoparticles to form metal compounds, so that the metal in the nanoparticles can form a synergistic catalytic system with the metal compounds.

[0013] Third, in the synthesis process of the nanocomposite material based on the porous carrier provided by the present invention, after drying and reducing the reaction product of the nanoparticle precursor and the porous carrier, the reaction product is directly etched in an air atmosphere without undergoing a high temperature treatment process of 600-1000°C, which simplifies the synthesis process and allows the doping elements to be well retained in the nanocomposite material, thereby allowing the aforementioned synergistic catalytic system to fully exert its effectiveness. The synthesis process of the present invention breaks through the limitations of existing catalyst preparation technology and can provide a new technical solution and implementation paradigm for the design of high-performance catalysts in the fields of fuel cells, chemical catalysis, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will describe the embodiments. Or a brief introduction is given to the drawings required for use in the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0015] Figure 1 This is a SEM image of the nanocomposite material prepared in Example 3e of the present invention; Figure 2 TEM image of the nanocomposite material prepared in Example 3e of the present invention; Figure 3 This is a schematic diagram of the structure of the nanocomposite material obtained in Example 3e of the present invention; Figure 4 TEM image of the nanocomposite material prepared in Example 5 of the present invention; Figure 5 This is an element scanning diagram of the nanocomposite material prepared in Example 5 of the present invention; Figure 6 TEM image of the nanocomposite material prepared in Comparative Example 3; Figure 7 is a SEM image of the nanocomposite material prepared in Comparative Example 4; Figure 8 TEM image of the nanocomposite material prepared in Comparative Example 4; Fig. 9 This is a schematic diagram of the structure of the nanocomposite material prepared in Comparative Example 4; Fig.10 The linear relationship diagram of the voltage power density-current density of the single cell membrane electrode of the catalysts prepared in Example 2, Example 4, Example 5, Comparative Example 1 and Comparative Example 5 of the present invention; Fig.11 The XRD diffraction patterns of the nanocomposites prepared in Examples 1 to 4 and Comparative Example 3 of the present invention are shown. DETAILED DESCRIPTION

[0016] As mentioned above, existing synthetic platinum-based catalysts and other nanocomposites based on porous carriers generally have the disadvantages of being difficult to adapt to high-temperature operating environments, and their synthesis processes are difficult to control the distribution position of nanoparticles in the carrier. In view of this, the inventors of the present invention have proposed the technical solution of the present invention after long-term research and a lot of practice. In summary, the present invention mainly adds an excessive amount of organic additives to the raw material system in the synthesis process of nanocomposites based on porous carriers. On the one hand, the organic additives are used to change the surface electronegativity of the porous carrier, drive the penetration of metal colloid particles as precursors of nanoparticles, the dynamic confinement fixation of solvent volatilization and the carrier-particle synergy, etc., to achieve precise control of the proportion of mesoporous nanoparticles. On the other hand, the organic additives are used to introduce doping elements, so that the metal compounds formed by the reaction of the doping elements with some metal elements constituting the nanoparticles and the metals in the nanoparticles form a synergistic catalytic system, thereby significantly improving the activity, stability and mass transfer efficiency of the nanocomposites.

[0017] The technical solution, implementation process and principle of the present invention will be further explained as follows.

[0018] Specifically, as one aspect of the technical solution of the present invention, a nanocomposite material based on a porous carrier includes a porous carrier and a plurality of nanoparticles supported by the porous carrier, wherein the nanoparticles contain a metal compound and a metal.

[0019] In some embodiments, the porous carrier has mesopores and other pores other than the mesopores, wherein the volume proportion of the mesopores is 50% to 90%, preferably 60% to 90%, and more preferably 80% to 85%. If the volume proportion of the mesopores is too small, it is difficult for the internal space of the mesopores to accommodate enough nanoparticles. If the volume proportion of the mesopores is too large, most of the nanoparticles are inside the mesopores of the porous carrier, and the resistance of oxygen passing through the pores is too large, which will also affect the performance.

[0020] In some embodiments, the nanoparticles are loaded in the mesopores and other pores outside the mesopores. If the mass of the nanoparticles in the mesopores is defined as M, the mass of the nanoparticles in other pores outside the mesopores is defined as N, and the total mass of the nanoparticles in the porous carrier is M+N, then M and N satisfy Fx=M / (M+N), and Fx≥0.3.

[0021] Furthermore, the mass of the nanoparticles in the mesopores and the mass of the nanoparticles in other pores outside the mesopores satisfy 0.3≤Fx≤0.9, preferably 0.5-0.6. If the proportion of nanoparticles in the mesopores is too large, the resistance of the reactants to the metal active sites is too large, affecting the performance. If the proportion of nanoparticles in the mesopores is too small, the metal active sites will directly contact the ionomer, poisoning the active sites and affecting the performance.

[0022] In some embodiments, the average particle size of the nanoparticles is 1-5 nm. The nanoparticles in the porous carrier-based nanocomposite material synthesized in the present invention are characterized by small size.

[0023] In some embodiments, the nanocomposite material further comprises a doping element, wherein part of the doping element is used to combine with part of the metal element in the nanoparticle to form the metal compound. In some cases, part of the doping element may also be distributed in the pore wall of the porous carrier.

[0024] In some preferred embodiments, the metal elements contained in the nanoparticles include one or a combination of two or more of Pt, Al, Ti, V, Cr, Mn, Co, Ni, etc., but are not limited thereto.

[0025] In some more preferred embodiments, the metal element is Pt, or the metal element includes a combination of one or more of Al, Ti, V, Cr, Mn, Co, Ni, etc. and Pt.

[0026] In some preferred embodiments, the mass ratio of the doping element to the metal element contained in the nanoparticles is 0.1 to 0.3, preferably 0.2 to 0.3. If the doping element is too much, it will cause pore blocking, and if the doping element is too little, the synthesized nanocomposite material will be larger in size, thereby reducing the catalyst activity.

[0027] Furthermore, the doping element may include one or more combinations of N, P, S, etc., but is not limited thereto.

[0028] Among them, taking the metal element Pt as an example, when N is selected as the doping element, the lone pair of electrons of N forms a Pt-N coordination bond with Pt, stabilizes the Pt nanoparticles, and regulates the electronic structure. The specific principle is: the electron donation effect of N increases the d-band center of Pt, enhances the electron transfer to reactants (such as H 2 , O 2 ) adsorption, improving hydrogen evolution (HER) and ORR activity. N-containing sites can form local positive charge sites, promoting O 2 adsorption and activation.

[0029] When P is selected as the doping element, the lone pair of electrons of P forms a Pt-P bond with Pt, inhibiting sintering and lowering the d-band center. The electronegativity of P is lower than that of C, and electrons are fed back to Pt, weakening intermediate poisoning (such as CO) and enhancing corrosion resistance. P doping improves the oxidation resistance of the carrier and prolongs the life of the catalyst.

[0030] When S is used as the doping element, S and Pt form PtS 2Compounds can change the electron cloud distribution and improve stability. Furthermore, defect sites can be introduced, S doping produces carbon lattice distortion, and increases the density of active sites. It also has a dual-functional catalytic effect, and the S site can adsorb H + or 2 , synergistically with Pt to promote reactions (such as ORR).

[0031] In some more preferred embodiments, the metal compound includes one or more combinations of metal sulfides, metal nitrides, metal phosphides, etc., but is not limited thereto.

[0032] Among them, taking the metal element Pt as an example, the metal in the nanoparticles can be metal platinum, and the metal compound can be a combination of one or more of platinum sulfide, platinum phosphide, platinum nitride, etc., but is not limited thereto.

[0033] In some embodiments, the mass ratio of the metal compound to the metal is 0.02 to 0.2, preferably 0.05 to 0.15, and the metal element in the metal compound is the same as at least part of the metal element in the metal. For example, the metal can be platinum or an alloy of platinum and a metal such as Al, Ti, V, Cr, Mn, Co or Ni, and the metal compound can be platinum sulfide. Too much metal compound will cause the loss of metal active sites and affect performance; too little metal compound will induce too little force to change the metal electronic structure.

[0034] In some embodiments, the material of the porous carrier includes one or more of carbon, metal oxide, silicon, silicon carbide, silicon nitride, but is not limited thereto. For example, the porous carrier may include porous graphite, porous graphene, SiC, SnO 2 、ZrO 2 One or more combinations of the above, but not limited to these.

[0035] In some preferred embodiments, the porous carrier is made of carbon material. Carbon-based materials have excellent electron transport properties and good compatibility with nanoparticles whose main components are metals.

[0036] In some embodiments, the ratio of the mass of the metal element contained in the nanocomposite material to the mass of the porous support is 1:4 to 3:2.

[0037] As another aspect of the technical solution of the present invention, it also relates to a method for preparing the aforementioned nanocomposite material based on a porous carrier, comprising: Allowing a liquid mixed reaction system comprising a metal source, an organic auxiliary agent and a solvent to fully react at room temperature to form a precursor liquid, wherein the organic auxiliary agent comprises a doping element; The porous carrier is dispersed in the precursor liquid and fully mixed and reacted at room temperature, and then the obtained reaction product is dried and reduced in sequence, and directly etched after the reduction treatment to obtain the nanocomposite material based on the porous carrier.

[0038] The organic auxiliary agent contains at least one active group, wherein at least one active group has a coordination function and is used to coordinate with metal ions derived from a metal source to form metal colloid particles. This active group can be defined as the first group.

[0039] Furthermore, the doping element may be distributed in the first group, and may be selected from but not limited to one or more combinations of N, P, S, etc.

[0040] By making the organic auxiliary agent exist in excess and maintaining its molar ratio with the metal source within an appropriate range, it can not only promote the reduction of at least part of the metal ions provided by the metal source to form metal colloid particles as nanoparticle precursors, but also provide doping elements to combine with part of the metal elements in the nanoparticles to form metal compounds, thereby changing the electronic structure of the metal in the nanoparticles, and further improving its catalytic activity and durability.

[0041] Furthermore, the molar ratio of the organic additive to the metal source is 1: 3 to 1: 1. If the molar ratio of the organic additive to the metal source is greater than 1: 1, the organic additive will cause partial pore blockage in the porous carrier, affecting the contact between the active sites inside the pores and the reactants. If the molar ratio of the organic additive to the metal source is less than 1: 3, the organic additive is too little, the metal ions will not be completely reduced, and the nanoparticle size will be too large.

[0042] Meanwhile, one or more active groups in the organic auxiliary agent are hydrophilic groups, which can be defined as the second group.

[0043] The first group and the second group may include one or more combinations of thiocarboxyl, sulfhydryl, sulfonic acid, hydroxyl, amine, nitro, phosphate, carboxyl, aldehyde and the like. In addition, the first group and the second group may be groups of the same type or groups of different types. For example, the first group and the second group may both be sulfhydryl.

[0044] When the porous carrier is porous carbon particles, etc., the amphiphilic hydrophobic groups of the organic auxiliary agent, such as its alkyl main chain, can be combined with the hydrophobic surface of the carrier, while its hydrophilic groups can interact outward with solvents such as water to form a hydrophilic layer, making the carrier easier to be wetted by the solvent.

[0045] In some embodiments, the organic auxiliary agent may include any one or more combinations of thioglycolic acid or its salt, L-cysteine ​​or its salt, ethylenediamine, glutathione, penicillamine, dithiothreitol, adenosine triphosphate, etc., but is not limited thereto. For example, the organic auxiliary agent may preferably be a thioglycolate salt such as STG (sodium thioglycolate). The thiol group contained in STG has a strong coordination ability and can combine with the metal ions provided by the metal source to form a complex. At the same time, STG has a mild reducing ability to slowly nucleate metal atoms, inhibit the excessive reduction and aggregation of metal ions, thereby effectively controlling the size of nanoparticles with metal as the main component. In addition, STG can modify the surface of the porous carrier through chemical bonding, increase the active sites on the surface of the porous carrier, and promote the uniform distribution of nanoparticles.

[0046] In some embodiments, the metal source may be a soluble metal salt. Further, the metal element contained in the metal salt may include any one or a combination of two or more of Pt, Al, Ti, V, Cr, Mn, Co, and Ni, for example, Pt, or a combination of one or more of Al, Ti, V, Cr, Mn, Co, and Ni and Pt, and is not limited thereto.

[0047] Exemplarily, the metal source may be an acid (such as chloroplatinic acid) or a salt containing the aforementioned metal element. Further, the metal source may be a nitrate, a hydrochloride, a sulfate or other forms of salts, such as potassium chloroplatinate, sodium chloroplatinate, platinum nitrate, platinum acetylacetonate, platinum sulfate, ammonium chloroplatinate, etc.

[0048] In some embodiments, the solvent includes water or a combination of water and an organic solvent. For example, the organic solvent may include acetone, methanol, ethanol, isopropanol, acetonitrile, etc., but is not limited thereto.

[0049] In some embodiments, the preparation method may specifically include: allowing the liquid phase mixed reaction system to react at room temperature for more than 1 hour, for example, 1 hour to 2 hours, to form the precursor liquid.

[0050] In some embodiments, the preparation method may specifically include: uniformly dispersing the porous carrier in the precursor liquid and fully reacting at room temperature, wherein the residual organic additive in the precursor liquid can change the surface electronegativity of the porous carrier, thereby prompting the metal colloid particles in a specified mass proportion in the precursor liquid to enter the mesopores in the porous carrier, and further convert them into nanoparticles in the mesopores, thereby achieving controllable loading of nanoparticles in the porous carrier.

[0051] If the nanoparticles loaded in the mesopores are defined as mesoporous nanoparticles, then generally speaking, the proportion of the mesoporous nanoparticles is positively correlated with the immersion time of the porous carrier in the precursor liquid.

[0052] Furthermore, the porous carrier can be dispersed in the precursor liquid and mixed and reacted at room temperature for more than 6 hours, preferably 6 hours to 36 hours, and then the reaction product can be separated from the reaction mixture. During the reaction, as the reaction time increases, the porous carrier continuously attracts metal colloid particles into the interior of the porous carrier, so that the mesoporous nanoparticles gradually increase. When the reaction time exceeds 36 hours, the internal enrichment force reaches saturation, and the mesoporous nanoparticles do not continue to be enriched with time. At this time, the proportion of mesoporous nanoparticles is 0.7~0.9.

[0053] In some embodiments, during the drying process of the present invention, only the solvent in the reaction mixture is volatilized and removed, and the remaining components are retained in the final reaction product.

[0054] In some embodiments, the reduction treatment is carried out in an atmosphere containing a reducing gas, the temperature of the reduction treatment is 200-500°C, and the time is 1-5 hours. Through this reduction treatment, the platinum precursor can be completely converted into metal , ensuring that the catalytic active sites are fully exposed. If the reduction treatment temperature is too high, irreversible sintering will occur, and if the reduction treatment temperature is too low, the reduction will be inadequate.

[0055] In some embodiments, the etching treatment is carried out in an air atmosphere, the etching treatment temperature is 200-500°C, and the time is 1-6 hours. This air etching treatment can remove amorphous carbon, dredge the pores, and improve mass transfer efficiency. If the etching treatment temperature is too high or the time is too long, the carrier structure will collapse. If the etching treatment temperature is too low or the time is too short, the effect of removing amorphous carbon and dredging the pores cannot be achieved.

[0056] In the preparation method of the present invention, air etching is directly performed on the reaction product after reduction treatment without high-temperature annealing and other processes, so that the metal compound can be stably retained in the nanoparticles to form a synergistic catalytic system with the metal components in the nanoparticles. At the same time, damage to the porous carrier structure and migration of nanoparticles caused by high-temperature treatment can be avoided, making the distribution position of the nanoparticles in the porous carrier more controllable.

[0057] The preparation process of the present invention has process compatibility and can be adapted to a variety of porous carriers and metal precursors. The activity, stability and mass transfer efficiency of the catalyst are optimized. This strategy provides a new paradigm for the design of high-performance catalysts in the fields of fuel cells, chemical catalysis, etc.

[0058] Furthermore, the preparation method of the present invention can synthesize small-sized, highly dispersible nanoparticles with metal as the main component, improve catalytic activity and stability, and also has the advantages of simple process (few steps, low equipment requirements), economic and efficient (low raw material and energy consumption costs, suitable for large-scale applications), and environmentally friendly (low solvent and by-product pollution, in line with the principles of green chemistry).

[0059] As another aspect of the technical solution of the present invention, it also relates to the use of the porous carrier-based nanocomposite material in the fields of preparing fuel cell catalysts or fuel cells.

[0060] Correspondingly, another aspect of the technical solution of the present invention further provides a fuel cell catalyst including the aforementioned nanocomposite material based on a porous carrier.

[0061] Another aspect of the technical solution of the present invention also provides a fuel cell, which includes the above-mentioned fuel cell catalyst.

[0062] In order to more clearly understand the purpose, technical solutions and advantages of the present invention, the following embodiments are combined to further explain the technical solutions, their implementation processes and principles. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0063] The mesopore proportion of the carrier used in the following embodiments is ≥50%, and the specific types can be porous carbon carrier (CMK1-C12-FA), tin oxide (Tiannai Technology-688116), silicon carbide (Beijing Dekedaojin Technology Co., Ltd.-DK-SiC-001), etc.

[0064] Example 1 In this embodiment, a method for preparing a platinum-carbon catalyst includes: S1. Add sodium thioglycolate and chloroplatinic acid in a molar ratio of about 1:1 into deionized water at room temperature, and stir at room temperature for about 2 hours to form a precursor solution.

[0065] S2. Add a porous carbon carrier (CMK1-C12-FA-2400) with a mesopore ratio of about 50% to the precursor liquid obtained in step S1, and control the mass ratio of the metal element in the metal source to the mass of the carbon carrier to be about 1:4. Stir at room temperature for about 6 hours, and then dry the obtained reaction mixture at a temperature of about 70°C to obtain a powder.

[0066] S3, placing the powder obtained in step S2 in a tube furnace for heating and reduction, the reduction conditions are: temperature of about 200 ° C, time of about 1 hour, reaction atmosphere of 5% H 2 / Ar mixed gas to obtain the reduced product.

[0067] S4. Wash the reduction product obtained in step S3 by using clean water and suction filtration until the conductivity of the filtrate is about 5 μs / cm, thereby obtaining a washed powder.

[0068] S5. The cleaned powder obtained in step S4 is subjected to air etching under the following conditions: temperature of about 200° C. and time of about 1 h to obtain the target product.

[0069] Example 1a The preparation method of a platinum-carbon catalyst provided in this embodiment is basically the same as that in Example 1, with the only difference being that a porous carbon carrier (CMK1-C12-FA-2000) with a mesopore ratio of about 60% is used in S2.

[0070] Example 1b The preparation method of a platinum-carbon catalyst provided in this embodiment is basically the same as that in Example 1, with the only difference being that a porous carbon carrier (CMK1-C12-FA-1600) with a mesopore ratio of about 70% is used in S2.

[0071] Example 1c The preparation method of a platinum-carbon catalyst provided in this embodiment is basically the same as that in Example 1, with the only difference being that a porous carbon carrier (CMK1-C12-FA-1200) with a mesopore ratio of about 80% is used in S2.

[0072] Example 1d The preparation method of a platinum-carbon catalyst provided in this embodiment is basically the same as that in Example 1, with the only difference being that a porous carbon carrier (CMK1-C12-FA-900) with a mesopore ratio of about 85% is used in S2.

[0073] Example 1e The preparation method of a platinum-carbon catalyst provided in this embodiment is basically the same as that in Example 1, with the only difference being that a porous carbon carrier (CMK1-C12-FA) with a mesopore ratio of about 90% is used in S2.

[0074] Example 2 In this embodiment, a method for preparing a platinum-carbon catalyst includes: S1. Add sodium thioglycolate and chloroplatinic acid in a molar ratio of about 1:2 into deionized water at room temperature, and stir at room temperature for about 2 hours to form a precursor solution.

[0075] S2. Add a porous carbon carrier (CMK1-C12-FA-1200) with a mesopore ratio of about 80% to the precursor liquid obtained in step S1, and control the mass ratio of the metal element in the metal source to the mass of the carbon carrier to be about 1:4. Stir at room temperature for about 12 hours, and then dry the obtained reaction mixture at a temperature of about 70°C to obtain a powder.

[0076] S3, placing the powder obtained in step S2 in a tube furnace for heating and reduction, the reduction conditions are: temperature about 300 ° C, time about 3h, reaction atmosphere 5% H 2 / Ar mixed gas to obtain the reduced product.

[0077] S4. Wash the reduction product obtained in step S3 by using clean water and suction filtration until the conductivity of the filtrate is about 5 μs / cm, thereby obtaining a washed powder.

[0078] S5. The cleaned powder obtained in step S4 is subjected to air etching under the following conditions: temperature of about 300° C. and time of about 3 h to obtain the target product.

[0079] Example 2a The preparation method of a platinum-carbon catalyst provided in this embodiment is basically the same as that in Example 2, except that in S1, the molar ratio of sodium thioglycolate to chloroplatinic acid is 1:3.

[0080] Example 2b The preparation method of a platinum-carbon catalyst provided in this embodiment is basically the same as that in Example 2, except that in S1, the molar ratio of sodium thioglycolate to chloroplatinic acid is 1:1.

[0081] Example 3 In this embodiment, a method for preparing a platinum-carbon catalyst includes: S1. Add sodium thioglycolate and chloroplatinic acid in a molar ratio of about 1:3 into deionized water at room temperature, and stir at room temperature for about 2 hours to form a precursor solution.

[0082] S2. Add a porous carbon carrier (CMK1-C12-FA-1200) with a mesopore ratio of about 80% to the precursor liquid obtained in step S1, and control the mass ratio of the metal element in the metal source to the mass of the carbon carrier to be about 1:4. Stir at room temperature for about 20 hours, and then dry the obtained reaction mixture at a temperature of about 70°C to obtain a powder.

[0083] S3, placing the powder obtained in step S2 in a tube furnace for heating and reduction, the reduction conditions are: temperature of about 400 ° C, time of about 5 h, reaction atmosphere of 5% H 2 / Ar mixed gas to obtain the reduced product.

[0084] S4. Wash the reduction product obtained in step S3 by using clean water and suction filtration until the conductivity of the filtrate is about 5 μs / cm, thereby obtaining a washed powder.

[0085] S5. The cleaned powder obtained in step S4 is subjected to air etching under the following conditions: temperature of about 500° C. and time of about 5 h to obtain the target product.

[0086] Example 3a The preparation method of a platinum-carbon catalyst provided in this embodiment is basically the same as that in Example 3, except that: S2, a porous carbon carrier (CMK1-C12-FA-1200) with a mesopore ratio of about 80% is added to the precursor liquid, and then stirred at room temperature for about 6 hours.

[0087] Example 3b The preparation method of a platinum-carbon catalyst provided in this embodiment is basically the same as that in Example 3, except that: S2, a porous carbon carrier (CMK1-C12-FA-1200) with a mesopore ratio of about 80% is added to the precursor liquid, and then stirred at room temperature for about 12 hours.

[0088] Example 3c The preparation method of a platinum-carbon catalyst provided in this embodiment is basically the same as that in Example 3, except that: S2, a porous carbon carrier (CMK1-C12-FA-1200) with a mesopore ratio of about 80% is added to the precursor liquid, and then stirred at room temperature for about 18 hours.

[0089] Example 3d The preparation method of a platinum-carbon catalyst provided in this embodiment is basically the same as that in Example 3, except that: S2, a porous carbon carrier (CMK1-C12-FA-1200) with a mesopore ratio of about 80% is added to the precursor liquid, and then stirred at room temperature for about 30 hours.

[0090] Example 3e The preparation method of a platinum-carbon catalyst provided in this embodiment is basically the same as that in Example 3, except that: S2, a porous carbon carrier (CMK1-C12-FA-1200) with a mesopore ratio of about 80% is added to the precursor liquid, and then stirred at room temperature for about 36 hours.

[0091] Example 4 In this embodiment, a method for preparing a platinum-carbon catalyst includes: S1. Add sodium thioglycolate and chloroplatinic acid in a molar ratio of about 1:2 into deionized water at room temperature, and stir at room temperature for about 2 hours to form a precursor solution.

[0092] S2. Add a porous carbon carrier (CMK1-C12-FA-1200) with a mesopore ratio of about 80% to the precursor liquid obtained in step S1, and control the mass ratio of the metal element in the metal source to the mass of the carbon carrier to be about 1:3. Stir at room temperature for about 20 hours, and then dry the obtained reaction mixture at a temperature of about 70°C to obtain a powder.

[0093] S3, placing the powder obtained in step S2 in a tube furnace for heating and reduction, the reduction conditions are: temperature of about 400 ° C, time of about 5 h, reaction atmosphere of 5% H 2 / Ar mixed gas to obtain the reduced product.

[0094] S4. Wash the reduction product obtained in step S3 by using clean water and suction filtration until the conductivity of the filtrate is about 5 μs / cm, thereby obtaining a washed powder.

[0095] S5. The cleaned powder obtained in step S4 is subjected to air etching under the following conditions: temperature of about 500° C. and time of about 5 h to obtain the target product.

[0096] Example 4a The preparation method of a platinum-carbon catalyst provided in this embodiment is basically the same as that in Embodiment 3, except that in S2, the mass ratio of the metal element in the metal source to the mass ratio of the carbon carrier is controlled to be approximately 1:2.

[0097] Example 4b The preparation method of a platinum-carbon catalyst provided in this embodiment is basically the same as that in Example 3, except that in S2, the mass ratio of the metal element in the metal source to the mass of the carbon carrier is controlled to be approximately 1:1.

[0098] Example 4c The preparation method of a platinum-carbon catalyst provided in this embodiment is basically the same as that in Example 3, except that in S2, the mass ratio of the metal element in the metal source to the mass ratio of the carbon carrier is controlled to be approximately 2:1.

[0099] Example 4d The preparation method of a platinum-carbon catalyst provided in this embodiment is basically the same as that in Example 3, except that in S2, the mass ratio of the metal element in the metal source to the mass ratio of the carbon carrier is controlled to be approximately 3:2.

[0100] Example 5 In this embodiment, a method for preparing a platinum-carbon catalyst includes: S1. Sodium thioglycolate, chloroplatinic acid and CoCl 2 Add deionized water, where chloroplatinic acid and CoCl 2 The molar ratio of the sum of the molar amounts of and sodium thioglycolate is about 2:1, and the mixture is stirred at room temperature for about 2 hours to form a precursor liquid.

[0101] S2. Add a porous carbon carrier (CMK1-C12-FA-1200) with a mesopore ratio of about 80% to the precursor liquid obtained in step S1, and control the mass ratio of the metal element in the metal source to the mass of the carbon carrier to be about 1:1. Stir at room temperature for about 20 hours, and then dry the obtained reaction mixture at a temperature of about 70°C to obtain a powder.

[0102] S3, placing the powder obtained in step S2 in a tube furnace for heating and reduction, the reduction conditions are: temperature about 500 ° C, time about 2 h, reaction atmosphere 5% H 2 / Ar mixed gas to obtain the reduced product.

[0103] S4. Wash the reduction product obtained in step S3 by using clean water and suction filtration until the conductivity of the filtrate is about 5 μs / cm, thereby obtaining a washed powder.

[0104] S5. The cleaned powder obtained in step S4 is subjected to air etching under the following conditions: temperature of about 200° C. and time of about 5 h to obtain the target product.

[0105] Example 6 In this embodiment, a method for preparing a platinum-carbon catalyst includes: S1. Sodium thioglycolate, chloroplatinic acid and MnSO 4 Add deionized water, where chloroplatinic acid and MnSO 4 The molar ratio of the sum of the molar amounts of and sodium thioglycolate is about 2:1, and the mixture is stirred at room temperature for about 2 hours to form a precursor liquid.

[0106] S2. Add silicon carbide with a mesoporous content of about 80% to the precursor liquid obtained in step S1, and control the mass ratio of the metal element in the metal source to the mass of the carbon carrier to be about 1:1. After stirring at room temperature for about 20 hours, dry the obtained reaction mixture at a temperature of about 70° C. to obtain a powder.

[0107] S3, placing the powder obtained in step S2 in a tube furnace for heating and reduction, the reduction conditions are: temperature about 500 ° C, time about 2 h, reaction atmosphere 5% H 2 / Ar mixed gas to obtain the reduced product.

[0108] S4. Wash the reduction product obtained in step S3 by using clean water and suction filtration until the conductivity of the filtrate is about 5 μs / cm, thereby obtaining a washed powder.

[0109] S5. The cleaned powder obtained in step S4 is subjected to air etching under the following conditions: temperature of about 200° C. and time of about 3 h to obtain the target product.

[0110] Example 7 In this embodiment, a method for preparing a platinum-carbon catalyst includes: S1. Sodium thioglycolate, chloroplatinic acid and TiCl 4 Add deionized water, where chloroplatinic acid and TiCl 4 The molar ratio of the sum of the molar amounts of and sodium thioglycolate is about 2:1, and the mixture is stirred at room temperature for about 2 hours to form a precursor liquid.

[0111] S2. Add tin oxide with a mesoporous content of about 85% to the precursor liquid obtained in step S1, and control the mass ratio of the metal element in the metal source to the mass of the carbon carrier to be about 1:1. Stir at room temperature for about 20 hours, and then dry the obtained reaction mixture at a temperature of about 70°C to obtain a powder.

[0112] S3, placing the powder obtained in step S2 in a tube furnace for heating and reduction, the reduction conditions are: temperature about 500 ° C, time about 2 h, reaction atmosphere 5% H 2 / Ar mixed gas to obtain the reduced product.

[0113] S4. Wash the reduction product obtained in step S3 by using clean water and suction filtration until the conductivity of the filtrate is about 5 μs / cm, thereby obtaining a washed powder.

[0114] S5. The cleaned powder obtained in step S4 is subjected to air etching under the following conditions: temperature of about 200° C. and time of about 6 hours to obtain the target product.

[0115] Example 8 The preparation method of a platinum-carbon catalyst provided in this embodiment is basically the same as that in Example 4, except that sodium thioglycolate is replaced by dithiothreitol.

[0116] Example 9 The preparation method of a platinum-carbon catalyst provided in this embodiment is basically the same as that in Example 4, except that sodium thioglycolate is replaced by L-cysteine.

[0117] Example 10 The preparation method of a platinum-carbon catalyst provided in this embodiment is basically the same as that in Example 4, except that sodium thioglycolate is replaced by penicillamine.

[0118] Embodiment 11 The preparation method of a platinum-carbon catalyst provided in this embodiment is basically the same as that in Example 4, except that sodium thioglycolate is replaced by adenosine triphosphate.

[0119] Comparative Example 1 The preparation method of a platinum-based catalyst provided in this comparative example is basically the same as that in Example 5, except that: In step S1, an excess amount of chloroplatinic acid is added, the molar ratio of sodium thioglycolate to chloroplatinic acid is about 1:5, and the mixture is stirred at room temperature for about 2 hours to form a precursor liquid.

[0120] Comparative Example 2 The preparation method of a platinum-based catalyst provided in this comparative example is basically the same as that in Example 5, except that: In step S1, an excess amount of sodium thioglycolate is added, the molar ratio of sodium thioglycolate to chloroplatinic acid is about 2:1, and the mixture is stirred at room temperature for about 2 hours to form a precursor liquid.

[0121] Comparative Example 3 The preparation method of a platinum-based catalyst provided in this comparative example is basically the same as that in Example 5, except that sodium thioglycolate is not added in step S1.

[0122] Comparative Example 4 The preparation method of a platinum-based catalyst provided in this comparative example is basically the same as that in Example 5, except that: In step S2, a carbon carrier is added to the precursor solution obtained in step S1, and then stirred at room temperature for about 2 hours.

[0123] Comparative Example 5 The preparation method of a platinum-based catalyst provided in this comparative example is basically the same as that in Example 5, the only difference is that the mesopore proportion of the porous carbon carrier used in step S2 is 30%.

[0124] Figure 1 , Figure 2 and Figure 3 The SEM image, TEM image and structural schematic diagram of the nanocomposite material prepared in Example 3e respectively show that Example 3e achieves the enrichment of platinum nanoparticles inside the mesopores.

[0125] Figure 4 TEM image of the nanocomposite material obtained in Example 5, Figure 5 This is an element scan of the nanocomposite material. It can be seen that the overlap of sulfur and platinum elements has an anchoring effect.

[0126] Figure 6 TEM image of the nanocomposite material obtained in Comparative Example 3; Figure 4 and Figure 6 It can be seen from the transmission electron microscope diagram that in Example 5 and Comparative Example 3, as the amount of organic additive added decreases from presence to absence, the size of the nanoparticles gradually increases. Therefore, the content of the organic additive will significantly affect the size of the metal nanoparticles.

[0127] Figure 7 , Figure 8 and Fig. 9The SEM image, TEM image and structural schematic diagram of the nanocomposite material prepared in Comparative Example 4 respectively show that Comparative Example 4 cannot achieve enrichment and loading of platinum nanoparticles inside the mesopores, and the proportion of platinum nanoparticles inside the mesopores is less than 0.3.

[0128] Fig.10 The linear relationship diagram of single cell membrane electrode voltage power density-current density of the catalysts prepared in Example 2, Example 4, Example 5, Comparative Example 1 and Comparative Example 5 shows that the performance of the examples is much higher than that of the comparative examples, and the performance of Example 5 reaches a peak.

[0129] Fig.11 The XRD diffraction patterns of the nanocomposites prepared in Examples 1 to 4 and Comparative Example 3 indicate that the organic additive promotes the presence of the metal compound.

[0130] The test method for the catalyst performance data shown in Table 2 is as follows: the electrochemical workstation is biologic-50e, the RDE device is the PINE electrode set sold by Hong Kong Physical and Chemical Company, and a three-electrode system is used: the working electrode is a catalyst-loaded glassy carbon electrode (PINE), the reference electrode is a saturated calomel electrode (SCE), and the counter electrode is a Pt carbon rod. The perchloric acid solution used in this test is 0.1 M. The scanning potential range of the cyclic voltammetry method is set to 0.05 V vs. RHE to 1.05 V vs. RHE, and the scanning rate is 50 mV s -1 The electrochemical specific surface area (ECSA) of platinum can be calculated from the adsorption area of ​​potential deposited hydrogen. The potential range of LSV test was 0.05 V vs. RHE to 1.05 V vs. RHE, and the scan rate was 10 mV s -1 The rotating disk electrode was rotated at 1600 rpm, and the ORR performance was evaluated by half-wave potential and mass activity (MA). Durability test: N 2 Saturated 0.1 M HClO 4In the test, a constant potential of 30s was first performed under the condition of 0.6 V / vs. RHE, and then a square wave cycle was performed at 0.95 V vs. RHE-0.6 V vs. RHE, wherein each potential was 3s, 6s was a cycle, and the cycle was 100,000. The activation and polarization curve tests of the membrane electrode were carried out in a hydrogen-air environment, the test temperature was 80°C, the test humidity was 90%RH, and the back pressure of the single cell test was 70kPa. Before the test, the membrane electrode was activated at a constant voltage of 0.3V until the current density reached a stable state. After stabilization, subsequent tests can be carried out, and the current density-voltage curve of the fuel cell is measured within a certain current range to obtain the peak power density of the material. High-temperature membrane electrode test activation and polarization curve tests were all carried out in a hydrogen-air environment, and the test temperature was above 105°C. The raw materials and amounts used in Examples 1 to 11 and Comparative Examples 1 to 5 are shown in Table 1, and the catalyst structure data obtained are shown in Table 2.

[0131] Table 1 Raw materials and dosage of Examples 1 to 11 and Comparative Examples 1 to 5 ;

[0132] Table 2 Catalyst structure data of Examples 1 to 11 and Comparative Examples 1 to 5

[0133] Note: The proportion of mesoporous nanoparticles = the mass of nanoparticles in the mesopores / (the mass of nanoparticles in the mesopores + the mass of nanoparticles in other pores outside the mesopores); the proportion of doping elements = the mass of doping elements / the mass of metal; the proportion of metal compounds = the mass of metal compounds / the mass of metal.

[0134] When the catalyst of the present invention is used in a fuel cell, the test performance data of the corresponding battery is shown in Table 3.

[0135] Table 3 Test performance of batteries

[0136] The activity of the catalysts of Examples 1 to 11 of the present invention was tested, and the results showed that the mass activity (MA) of these catalysts could be increased to 720 mA / mgPt (0.9 V vs. RHE), which is much higher than 200 mA / mgPt of current commercial catalysts, which may be attributed to the high dispersion of internal nanoparticles and the enhanced intrinsic activity due to the confinement effect.

[0137] The stability of the catalysts of Examples 1 to 11 of the present invention was tested, and the results showed that in an accelerated aging test (ADT), the ECSA decay rate of these catalysts could be reduced to 6%, which is much lower than the 50% of current commercial catalysts. This should be due to the significant confinement effect of the carrier, which effectively inhibits the dissolution and agglomeration of platinum.

[0138] Furthermore, the mass activity of the half-cell prepared based on the catalysts of Examples 1 to 11 of the present invention is 400 to 720.04 mA / mg Pt (0.9 V vs. RHE), the peak power density of a single cell at 80°C is 1.06~2.0W / cm 2 , and the peak power density of the single cell at an operating temperature of 105°C is 0.93~1.55W / cm 2 .

[0139] In addition, the applicant also referred to the preparation methods of Examples 1 to 11 above, conducted experiments using other raw materials and process conditions listed in this specification, and tested the composition, structure and application performance of the products obtained from these experiments with the help of a series of characterization methods described above, and found that they have good performance in catalytic activity, stability, etc. For example, the applicant used graphene (NanoXplore-XG-Porous), graphite phase carbon nitride (carbon nitride-Xi'an Ruixi Biological Company-RC-1220), and metal organic framework material (BASF-CALF-20) to replace the porous carbon carrier in Example 4, and the mass activity of the obtained catalyst products was above 450 mA / mgPt (0.9 V vs.RHE), and the ECSA decay rate was below 15%.

[0140] Although the above embodiments of the present invention have been described in detail, professionals in the relevant field may delete and modify them once they know the creative content and concepts, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the attached claims.

[0141] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

Claims

1. A nanocomposite material based on a porous carrier, comprising a porous carrier and nanoparticles supported by the porous carrier, characterized in that: The nanocomposite material also meets the following conditions: (1.1) The porous carrier has mesopores and other pores other than the mesopores, wherein the volume proportion of the mesopores is 50% to 90%; (1.2) The nanoparticles are loaded in the mesopores and other pores outside the mesopores. The mass of the nanoparticles in the mesopores is defined as M, and the mass of the nanoparticles in other pores outside the mesopores is defined as N. Then Fx≥0.3, Fx=M / (M+N); (1.3) The nanoparticles comprise a metal and a metal compound, the mass ratio of the metal compound to the metal is 0.02 to 0.2, and the metal element in the metal compound is the same as at least part of the metal element in the metal; (1.4) The nanocomposite material further comprises a doping element, wherein a portion of the doping element is used to form the metal compound, and a mass ratio of the doping element to the metal element contained in the nanoparticles is 0.1 to 0.

3.

2. The porous carrier-based nanocomposite material according to claim 1, characterized in that: Fx is 0.3~0.

9.

3. The porous carrier-based nanocomposite material according to claim 1, characterized in that: The average particle size of the nanoparticles is 1-5 nm.

4. The porous carrier-based nanocomposite material according to claim 1, characterized in that: The metal element includes any one or a combination of two or more of Pt, Al, Ti, V, Cr, Mn, Co, and Ni, and the doping element includes one or more of N, P, and S.

5. The porous carrier-based nanocomposite material according to claim 4, characterized in that: The metal element is Pt, or the metal element includes one or a combination of two or more of Al, Ti, V, Cr, Mn, Co, and Ni and Pt.

6. The porous carrier-based nanocomposite material according to claim 5, characterized in that: The metal compound includes one or more combinations of metal sulfides, metal nitrides, and metal phosphides.

7. The porous carrier-based nanocomposite material according to claim 1, characterized in that: The material of the porous carrier includes one or more combinations of carbon, metal oxides, silicon, silicon carbide, and silicon nitride.

8. A method for preparing the nanocomposite material based on a porous carrier according to any one of claims 1 to 7, characterized in that: include: Allowing a liquid mixed reaction system comprising a metal source, an organic auxiliary agent and a solvent to fully react at room temperature to form a precursor liquid, wherein the molar ratio of the organic auxiliary agent to the metal source is 1:3 to 1:1, and the organic auxiliary agent comprises a doping element; The porous carrier is dispersed in the precursor liquid and fully mixed and reacted at room temperature, and then the obtained reaction product is dried and reduced in sequence, and then directly etched after the reduction treatment, so as to obtain the nanocomposite material based on the porous carrier.

9. The method according to claim 8, characterized in that: The organic auxiliary agent contains a first group and a second group, wherein the first group and the second group include a combination of one or more of thiocarboxyl, mercapto, sulfonic acid, hydroxyl, amine, nitro, phosphoric acid, carboxyl, and aldehyde.

10. The method according to any one of claims 8 to 9, characterized in that: The organic auxiliary agent includes one or more combinations of thioglycolic acid or its salt, L-cysteine ​​or its salt, ethylenediamine, glutathione, penicillamine, dithiothreitol, and adenosine triphosphate.

11. The method according to claim 8, characterized in that: The metal source includes a soluble metal salt, and the metal elements contained in the metal salt include any one or a combination of two or more of Pt, Al, Ti, V, Cr, Mn, Co, and Ni; and / or the solvent includes water or a combination of water and an organic solvent.

12. The method according to claim 8, characterized in that Specifically include: The liquid phase mixed reaction system is reacted at room temperature for more than 1 hour to form the precursor liquid.

13. The method according to claim 8, characterized in that Specifically include: The porous carrier is dispersed in the precursor liquid and mixed and reacted at room temperature for more than 6 hours, and then the reaction product is separated from the reaction mixture to obtain the reaction product.

14. The method according to claim 8, characterized in that: The reduction treatment is carried out in an atmosphere containing a reducing gas, the temperature of the reduction treatment is 200-500° C., and the time is 1-5 hours.

15. The method according to claim 8, characterized in that: The etching process is carried out in an air atmosphere at a temperature of 200-500° C. and for a time of 1-6 hours.

16. Use of the porous carrier-based nanocomposite material according to any one of claims 1 to 7 in the preparation of a fuel cell catalyst or a fuel cell.

17. A fuel cell catalyst, characterized in that: A nanocomposite material based on a porous carrier according to any one of claims 1 to 7.

18. A fuel cell, characterized in that: Comprising the fuel cell catalyst according to claim 17.

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