Carbon material for catalyst carrier, preparation method of carbon material, catalyst and fuel cell

Abstract

The invention discloses a carbon material for a catalyst carrier, a preparation method of the carbon material, a catalyst and a fuel cell, and relates to the technical field of cells, the carbon material for the catalyst carrier has a graphite microcrystal structure, the interplanar spacing d002 of graphite microcrystals measured by an X-ray diffraction method is less than 0.355 nm, the grain size La of the graphite microcrystals is 2-14 nm, and the diameter of the graphite microcrystals is 10-20 nm. The longitudinal stacking height Lc of the graphite microcrystals is 1.5-13nm, the specific surface area SBET of the carbon material is 100m < 2 > / g-1200m < 2 > / g, and the carbon material meets the condition that phi is greater than or equal to 30% and less than or equal to 95%; phi is the grain interstitial degree of the carbon material, # imgabs0 #. The problem that an existing carbon material for a catalyst carrier cannot effectively balance the high specific surface area and the high order degree can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a carbon material for a catalyst carrier, a preparation method thereof, a catalyst and a fuel cell. Background Art

[0002] A proton exchange membrane fuel cell (PEMFC) is a device that directly converts chemical energy into electrical energy and thermal energy through the electrochemical reaction of hydrogen and oxygen. Its core components include a proton exchange membrane, a catalyst layer, a gas diffusion layer, and a bipolar plate.

[0003] The catalyst layer includes a carbon material loaded with a catalyst, an ion conductor, and other possible added components. In order to promote electron transfer between electrode materials and optimize battery performance, carbon materials with high specific surface area and rich pores are often selected as catalyst supports. Among them, carbon black materials such as acetylene black, Vulcan XC-72R (Chinese name: Cabot XC-72R) and Ketjen black (Chinese name: Ketjen black) are widely used, with specific surface areas ranging from 50 to 1200 m 2 / g, combining high conductivity and a suitable pore structure, allowing platinum particles to be evenly dispersed on its surface. However, due to the low order of the carbon layer of carbon black materials, there is a high risk of carbon corrosion during long-term operation, which in turn has a negative impact on electrochemical stability. Traditional graphite materials, while highly ordered, have a specific surface area of less than 50 m² / g and cannot provide sufficient active sites. In addition, graphene obtained through metal intercalation or carbon nanotubes prepared by high-temperature metal catalysis, while relatively ordered and high in specific surface area, have a high metal content and are prone to damage to the proton membrane. Summary of the Invention

[0004] The main purpose of the present invention is to propose a carbon material and a preparation method thereof, a fuel cell catalyst and a fuel cell, aiming to solve the problem that existing carbon materials used as catalyst supports cannot effectively balance high specific surface area and high order.

[0005] To achieve the above object, the present invention provides a carbon material for catalyst support, which has a graphite microcrystalline structure, wherein the interplanar spacing d of the graphite microcrystalline measured by X-ray diffraction is 002 <0.355nm, the lateral size La of the graphite microcrystal is 2nm~14nm, the longitudinal stacking height Lc of the graphite microcrystal is 1.5nm~13nm; the specific surface area S of the carbon material BET 100m 2 / g~1200m 2 / g, and the carbon material satisfies: 30%≤Φ≤95%; Φ is the intergranular spacing of the carbon material; .

[0006] In some embodiments, the specific surface area S of the carbon material is BET 400m 2 / g~1200m 2 / g, La is 2nm~6nm, Lc is 1.5nm~5nm, and the grain spacing Φ is 50%-95%.

[0007] In some embodiments, the specific surface area S of the carbon material is BET 100m 2 / g~400m 2 / g, La is 3.5nm~13nm, Lc is 2nm~13nm, and the grain spacing Φ is 30%~55%.

[0008] In some embodiments, the total metal content of the carbon material is less than 100 ppm, and the metal includes any one or more of Fe, Co, Ni, Cr, Mn, Cu, Al, Zn, Na, K, Ca, and Mg.

[0009] In some embodiments, the carbon material has a G peak position at 1580 cm in the Raman spectrum. -1 ~1590cm -1 The half-peak width of the G peak is 25 cm -1 ~50cm -1 ; And / or, the intensity ratio of the 2G peak to the G peak of the carbon material in the Raman spectrum is 2G / I G 0.2~0.8; And / or, the Dv50 particle size of the carbon material is 20 nm to 1000 nm.

[0010] The present invention also provides a method for preparing a carbon material for a catalyst support, comprising the following steps: carbonizing an organic carbon source in an inert atmosphere at 800°C to 1500°C for 0.5 to 8 hours to obtain an intermediate A; subjecting the intermediate A to a pore-forming treatment in a mixed atmosphere of an activated gas and an inert gas at 400°C to 600°C for 0.5 to 5 hours to form a porous product; crushing the porous product into nano-sized particles; The carbon material is obtained by graphitizing the nano-scale particles.

[0011] In some embodiments, the organic carbon source includes at least one of phenolic resin, polyimide, polystyrene, lignin, coal tar, asphalt, benzopyrene, polyacrylonitrile, polyvinyl alcohol, polyethylene, polyvinylidene chloride, cellulose, carboxymethyl cellulose, citric acid, melamine, nitroethylcarbazole, and thiophene; And / or, the volume ratio of the activated gas to the inert gas is 5:95 to 10:90; the activated gas includes at least one of H2O, O2, O3, CO2, and air; And / or, the particle size of the nano-scale particles is 20 nm to 1000 nm.

[0012] And / or, the temperature of the graphitization treatment is 1800° C. to 2800° C., and the treatment time is 0.5 h to 3 h.

[0013] An embodiment of the present invention further provides a catalyst comprising a carbon support and platinum particles loaded on the carbon support, wherein the carbon support comprises the aforementioned carbon material for a catalyst support, or a carbon material obtained by the aforementioned method for preparing the carbon material for a catalyst support.

[0014] In some embodiments, based on 100% mass of the catalyst, the mass percentage of the platinum particles in the catalyst is 20% to 60%; and / or the average particle size of the platinum particles is 1 nm to 5 nm.

[0015] An embodiment of the present invention further provides a fuel cell, comprising a catalyst layer, wherein the catalyst layer comprises the above-mentioned catalyst.

[0016] Compared with the prior art, the present invention has the following advantages: According to the experimental results, the carbon material of this technical solution has a specific surface area of 100-1200 m 2 / g, interplanar spacing d 002 <0.355 nm, La is 2nm~14nm, and Lc is 1.5nm~13nm. By limiting the grain gap Φ within the range of 30%-95%, the carbon material has a high specific surface area and a high degree of order at the same time, effectively balancing the high specific surface area and high order, thereby improving the cycle retention rate and corrosion resistance of the carbon material.

[0017] The preparation method of the present application controls the structure of carbon materials through a phased process to solve the technical bottlenecks of the difficulty in coordinating high specific surface area and high order, metal catalyst contamination and pore closure in the preparation of traditional carbon carriers. In the carbonization treatment stage, the organic carbon source is promoted to undergo aromatization and polycondensation in a high-temperature inert environment to form an initial graphite microcrystalline skeleton. Its temperature-time window controls the density of carbon layer defects and the degree of microcrystalline growth; the pore-forming treatment selectively etches the amorphous region of the carbon skeleton in an oxidizing mixed atmosphere, while retaining the microcrystalline structure, introducing an open pore network to avoid pore collapse caused by complete graphitization; the nano-scale crushing process depolymerizes carbon particle aggregates through mechanical energy input to form nanoparticles of uniform size, providing a uniform grain growth substrate for subsequent graphitization, while preventing pore closure caused by particle fusion during high-temperature treatment; the final graphitization stage reconstructs the carbon layer arrangement under metal-free catalysis conditions, eliminates grain boundary stress through high-temperature annealing, and improves the stacking order and conductivity of the carbon layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0019] Figure 1 A schematic diagram of the grain structure of a carbon material according to an embodiment of the present invention; Figure 2 Schematic diagram of carbon grains and their pore structure loaded with platinum in a carbon material according to an embodiment of the present invention; Figure 3 This is a Raman spectrum of the carbon material of Example 1 of the present invention; Figure 4 This is a TEM image of the carbon material of Example 1 of the present invention.

[0020] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0021] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0022] " range " disclosed in the present application is limited in the form of lower limit and upper limit, and given range is limited by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of special range. The scope limited in this way can be to include end value or not include end value, and can be arbitrarily combined, that is, any lower limit can form a range with any upper limit combination. For example, if the scope of 60-120 and 80-110 is listed for specific parameters, it is understood that the scope of 60-110 and 80-120 is also expected. In addition, if the minimum range value 1 and 2 are listed, and if the maximum range value 3,4 and 5 are listed, then the following range can all be expected: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5. In this application, unless otherwise specified, the numerical range " ab " represents the abbreviation of any real number combination between a and b, wherein a and b are all real numbers. For example, a numerical range of "0-5" indicates that all real numbers between "0-5" are listed herein, and "0-5" is simply an abbreviation for these numerical combinations. Furthermore, when a parameter is expressed as an integer ≥ 2, this is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0023] Unless otherwise specified, all embodiments and optional embodiments of the present application can be combined with each other to form a new technical solution.

[0024] Unless otherwise specified, all technical features and optional technical features of this application can be combined with each other to form a new technical solution.

[0025] Unless otherwise specified, all steps of the present application may be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), indicating that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially. For example, the method may further include step (c), indicating that step (c) may be added to the method in any order, for example, the method may include steps (a), (b) and (c), or may include steps (a), (c) and (b), or may include steps (c), (a) and (b), etc.

[0026] Fuel cells operate in a high-potential, oxygen-rich environment, which can easily lead to electrochemical oxidation corrosion of carbon materials. Carbon corrosion not only causes the electrode layer structure to collapse and the pore structure to deteriorate, but can also cause the active material to fall off, ultimately affecting the performance of the fuel cell. Traditional graphite materials have excellent corrosion resistance, but their specific surface area is usually less than 50m 2 / g, which cannot provide enough active sites.

[0027] On the other hand, carbon black and amorphous carbon materials such as activated carbon exhibit high specific surface areas (over 1000 m 2 / g) and possess abundant active material loading sites. However, due to the low degree of order and the presence of a large number of defect sites in these materials, their electrochemical corrosion resistance is poor.

[0028] In addition, although graphene obtained by metal intercalation or carbon nanotubes prepared by high-temperature metal catalysis are relatively ordered and have a high specific surface area, their metal content is high and they can easily damage the proton membrane.

[0029] Therefore, there is still a need for a carbon material with both high specific surface area and high order as a catalyst carrier to support fuel cells to achieve high performance levels and long operating life.

[0030] Based on this, the embodiment of the present invention provides a carbon material for a catalyst carrier, which has a graphite microcrystalline structure, and the interplanar spacing d of the graphite microcrystalline measured by X-ray diffraction is 002 <0.355nm, the lateral size La of the graphite microcrystal is 2nm~14nm, and the longitudinal stacking height Lc of the graphite microcrystal is 1.5nm~13nm; the specific surface area S of the carbon material BET 100m 2 / g~1200m 2 / g, and the carbon material satisfies: 30%≤Φ≤95%; Φ is the grain spacing of the carbon material.

[0031] The carbon material used as a catalyst carrier in this technical solution achieves the synergistic optimization of high specific surface area and order through specific structural parameters to improve the performance and durability of fuel cell catalysts. The graphite microcrystalline structure refers to the microscopic morphology composed of short-range ordered graphite layered units inside the material. 2 The arrangement of hybrid carbon layers exhibits graphite-like characteristics, but the grain size is small and the long-range order is limited.

[0032] Catalyst carriers need to use materials with high specific surface areas to load catalysts, especially carbon-based catalysts for fuel cells, which can load active substances as much as 50%wt or more. However, the specific surface area is the total surface area per unit mass of the material. The higher the specific surface area, the richer the exposed surface of the material, which requires reducing the particle size of the material to increase the surface area per unit mass. The smaller the particle size of the material, the higher the surface energy, and the more susceptible the carbon carrier is to carbon corrosion. Improving the corrosion resistance of the carbon material requires increasing the order of the material and reducing the contact surface between the material and the environment. This contradicts the characteristic that "the carbon carrier needs to have a high specific surface area to achieve high load".

[0033] To obtain carbon materials with high specific surface area and high degree of order, one can either crush the highly ordered material to increase the specific surface area, or first obtain a small-grained high-specific surface area material and then subject it to high-temperature treatment to orderly grain growth. The latter option is usually adopted, which is easier to obtain high-specific surface area materials. However, during the grain growth process, in addition to the reduction in surface area caused by grain growth, there is also a loss of surface area due to excessive growth of some grains, the squeezing of adjacent grains, and the resulting closure of crystal faces. The reduction in the pores of the closed crystal faces leads to a decrease in mass transfer during the catalytic reaction, and this loss of surface area needs to be avoided.

[0034] The applicant has found that by calculating the theoretical specific surface area of the material through the grain size and controlling the reasonable range of the ratio of the measured specific surface area to the theoretical specific surface area of the material, a material with both high specific surface area and high grain order can be obtained, balancing the material's platinum loading performance and durability.

[0035] Specifically, in this application, the grain spacing is calculated by formula (a): (a).

[0036] This technical solution refines the relationship between the specific surface area and grain size of carbon materials by quantitatively defining the grain spacing Φ. The grain spacing Φ represents the ratio of the actual specific surface area per unit mass of carbon material to the theoretical grain specific surface area. Its calculation is based on the measured specific surface area of the material (S BET ) and theoretical specific surface area (S Grain ) percentage relationship, where S Grain Φ is a term or parameter defined as the specific surface area of a material when all grains are separated from each other. This assumes that the grains themselves are perfectly crystalline. Due to their extremely small size (a few nanometers), it is difficult to create pores within them. Therefore, all pores in the material originate from the spaces between the grains. This parameter reflects the richness of the pore structure formed by the stacked grains. When the Φ value approaches 100%, the material's grains are considered to be almost completely separated and disconnected. When the intergranular gap is smaller than a nitrogen molecule (0.26 nm in diameter), the grain boundaries are considered closed. The area of the closed grain interface cannot be measured, resulting in the measured value being lower than the theoretical value. The following is a detailed derivation of the formula for intergranular gap Φ.

[0037] Usually carbon material particles are assembled from a large number of crystal grains. When the particle is composed of only one crystal grain, the crystal grains are completely separated and not connected. During the nitrogen adsorption and desorption test, nitrogen molecules can contact every crystal surface, so the specific surface area (S BET ) should be equal to the specific surface area per unit mass of the grain (S Grain). Usually, after heat treatment, there are van der Waals forces, meshing forces between defects, and some chemical bonding between grains in carbon materials, which causes the grains to stick together, resulting in the closure of some grain boundaries and the inability of nitrogen molecules to penetrate. The measured specific surface area is smaller than the specific surface area of the grains. It can also be inferred that for particles composed of grains of the same size, the more permeable gaps between grains, the higher the S BET The larger the value is, the smaller the grain size is. Therefore, this patent defines the grain spacing as grain spacing = specific surface area measured by nitrogen adsorption and desorption (S BET ) divided by the specific surface area per unit mass of the grains (S Grain )×100%, as shown in formula (1). The pore richness of the material is characterized by the intergranularity.

[0038] , (1) The average specific surface area per unit mass of grains (S Grain ), can be calculated by the following formula (2): , (2) like Figure 1 As shown, the carbon material is a rectangular structure with a grain size of La nm and a longitudinal stacking height of Lc nm.

[0039] La can be calculated from the intensity ratio of the D peak and the G peak in the Raman spectrum of carbon (Raman laser wavelength λ = 514 nm), as shown in Formula 3: , (3) Lc can be calculated from the XRD (002) crystal plane diffraction peak characteristics of carbon using the Scherrer formula (X-ray wavelength λ = 0.15406 nm, β is the half-maximum width of the (002) crystal plane diffraction peak, and ϴ is the (002) crystal plane diffraction angle), as shown in Formula 4: , (4) The average surface area of a single crystal is: , (5) The average single crystal volume is: , (6) Through the interplanar spacing d 002 The average carbon grain density that has not reached the complete graphite state is calculated by the size change of (nm). (The density of graphite crystals with a graphite interplanar spacing of 0.335nm is 2.26g / cm 3 . ) , (7) Then the grain spacing Φ, (a) This technical solution is in d002 <0.355nm, La is 2nm~14nm, Lc is 1.5nm~13nm, specific surface area S BET 100m 2 / g~1200m 2 / g, by limiting the Φ value to the range of 30%-95%, a balance between multi-scale pore distribution and ordered structure was established. Traditional high-specific surface area carbon materials produce excessive micropores due to disordered grain stacking, resulting in the entrapment of catalyst metal particles; while graphite materials have insufficient porosity due to excessively large grains, resulting in a low specific surface area. The introduction of the Φ value establishes a mathematical model linking grain size, interlayer spacing, and specific surface area, allowing the material to form an open pore structure by adjusting the grain stacking method while maintaining a high specific surface area. This structural feature mainly dominates the pore distribution through the intergranular gaps rather than the intracrystalline micropores, reducing the deactivation of active sites caused by the embedding of platinum catalysts into micropores, and the mesoporous network formed by the orderly arrangement between the grains promotes the transport of reaction protons.

[0040] In addition, by calculating the limited grain interstitial space Φ, the problem of the difficult balance between high specific surface area and high order in traditional carbon materials was solved. This numerical range allows the carbon material to have open pores inside to provide a high specific surface area, while maintaining structural stability through close connection between grains. The introduction of formula (a) makes the grain interstitial space a parameter that can be quantified and controlled. This formula relates the specific surface area measured by nitrogen adsorption and desorption to the theoretical specific surface area per unit mass of grains, accurately reflecting the accessibility of the pores between grains. This technical means is applied to the high-temperature graphitization process to avoid the situation where pore closure leads to a decrease in specific surface area. The coupling effect of grain interstitial space and grain size provides sufficient dispersion sites and catalytic reaction transmission channels for the catalyst under fuel cell operating conditions, and inhibits the electrochemical oxidation corrosion of the carbon matrix through orderly arrangement of grains.

[0041] See Figure 2 , Figure 2 The microstructure of the material of this application and its optimization effect on platinum particle loading are intuitively demonstrated. The figure shows that graphite microcrystals (lateral size La, longitudinal stacking height Lc) form a three-dimensional network through orderly arrangement, and the intergranular gaps (Φ value) form open mesoporous / macroporous channels. The pores are mainly distributed in the intergranular gaps (micropores in amorphous crystals), avoiding the problem of traditional carbon black micropores embedding platinum particles. Platinum particles can be evenly dispersed on the surface of the grains and the edge of the pores, rather than embedded in the deep micropores, so that the active sites are fully exposed to the reaction interface. The short-range ordered carbon layer (d 002 <0.355 nm) by strong sp 2 Bonding enhances the anchoring stability of platinum particles and inhibits agglomeration or shedding.

[0042] In some embodiments, the specific surface area S of the carbon material is BET100m 2 / g~400m 2 / g, La is 3.5nm~13nm, Lc is 2nm~13nm, and the grain spacing Φ is 30%~55%.

[0043] In some embodiments, the specific surface area S of the carbon material is BET 400m 2 / g~1200m 2 / g, La is 2nm~6nm, Lc is 1.5nm~5nm, and the grain spacing Φ is 50%~95%.

[0044] This technical solution divides the specific surface area into intervals and uses the grain gap Φ as the basis to determine the grain size La and longitudinal stacking height Lc that are suitable for each specific surface area interval, so as to balance the high specific surface area and high order of the carbon material used as the catalyst carrier.

[0045] Specifically, when the specific surface area is 100m 2 / g~400m 2 / g, the grain size La and Lc can be adjusted to be within the range of 30%~55% to make the grain size La and Lc 2 / g~400m 2 / g of specific surface area, achieving a catalyst cycle performance of more than 90%, making the carbon material suitable for application scenarios with high requirements for catalyst cycle life.

[0046] When the specific surface area is 400m 2 / g~1200m 2 / g, the grain size La and Lc can be adjusted to 400m by adjusting the grain spacing within the range of 50%~95%. 2 / g~1200m 2 / g specific surface area to achieve a better matching relationship, and the electrochemical active surface area (ECSA) reaches 90m 2 / g-Pt or above, making the carbon material suitable for application scenarios requiring high catalytic activity.

[0047] This technical solution allows for flexible adjustment of material properties according to the needs of specific application scenarios. For example, in conditions where a higher catalyst cycle life is required, 100m 2 / g~400m 2 / g specific surface area range, and then control the grain size La and Lc according to the grain spacing to achieve a balance between high specific surface and high order. In the application scenario where high catalytic activity is sought, 400m 2 / g~1200m 2 In the specific surface area range of 10 ...

[0048] In some embodiments, the total metal content of the carbon material is less than 100 ppm, and the metal includes any one or more of Fe, Co, Ni, Cr, Mn, Cu, Al, Zn, Na, K, Ca, and Mg. Specifically, compared to the scheme of "obtaining a relatively ordered and high specific surface area carbon support material by metal intercalation or metal catalysis", the carbon material of the present application does not add additional metal materials during the preparation process, thereby making the total metal content of the carbon material less than 100 ppm, which can reduce damage to the proton membrane. It should be noted that the metals in the carbon material of the present application mainly come from the production equipment (such as carbonization furnace, ball mill, etc.), metal impurities entrained in the production raw materials, etc. Therefore, when actually implementing the scheme of the present application, the production equipment can be optimized or the production process can be controlled as needed to make the total metal content of the carbon material less than 90 ppm, 80 ppm, 70 ppm, 60 ppm, 50 ppm, etc. For example, when the metal in the carbon material mainly comes from the wear of the inner wall of the carbonization furnace, an inert ceramic coating can be sprayed on the inner wall of the carbonization furnace; or, when the metal in the carbon material mainly comes from the metal impurities in the organic carbon source, the organic carbon source can be purified first, and then the carbon material of the present application can be prepared.

[0049] In some embodiments, the carbon material has a G peak position at 1580 cm in the Raman spectrum. -1 ~1590cm -1 The half-peak width of the G peak is 25 cm -1 ~50cm -1 .

[0050] The G peak in the Raman spectrum corresponds to the sp 2 The in-plane vibration mode of hybrid carbon atoms has a peak position at 1580~1590cm -1 The range indicates that there is moderate electronic coupling between carbon layers, which is different from the higher wavenumber characteristics of completely disordered carbon black (>1590cm -1 ) and lower wavenumber characteristics of complete graphitization (<1580cm -1 ), reflecting that the material has both defect site activity and structural stability. The d 002Interplanar spacing is the distance between layers of the graphite (002) crystal plane. A value less than 0.355 nm indicates that the carbon layers are stacked close to the density of ideal graphite (0.335 nm for ideal graphite), indicating that the material has a high degree of graphitization order. The lateral dimension La refers to the average size of the graphite crystallites along the plane of the carbon layer, and the longitudinal stacking height Lc refers to the thickness of the carbon layers stacked in the vertical direction. The limitations of these two (La: 2-15nm, Lc: 1.5-15nm) enable the formation of a controllable grain boundary distribution of the crystallites at the nanoscale, maintaining high specific surface area while avoiding pore closure caused by excessive grain growth.

[0051] This technical solution uses high specific surface area (100~1200m 2 The combined design of carbon black and ordered graphite microcrystal structure addresses the performance contradictions of traditional carbon supports in fuel cell environments: carbon black materials with high specific surface area have poor corrosion resistance due to their disordered structure, while highly ordered graphite materials have limited catalyst dispersion due to their low specific surface area. 002 The value indicates that the material forms a stable short-range ordered structure at the atomic scale. This structure reduces the electrochemical corrosion rate by enhancing the conjugation between carbon layers. The specific range design of La and Lc forms a balanced distribution between grain boundaries and pores at the nanoscale. On the one hand, it provides highly dispersed sites and catalytic reaction transmission channels for the platinum catalyst, and on the other hand, it reduces the defect density of the carbon layer by controlling the grain size. As a result, this carbon material exhibits optimized comprehensive performance in fuel cell applications: the high specific surface area supports high catalyst particle loading and sufficient exposure of active sites, the ordered microcrystalline structure inhibits oxidative degradation of the carbon matrix, and the coordinated distribution of grain boundaries and pores promotes the transmission efficiency of reactants, protons, and electrons.

[0052] In some embodiments, the carbon material has an intensity ratio of the 2G peak to the G peak in the Raman spectrum of 2G / I G It is 0.2~0.8.

[0053] This technical solution further refines the evaluation dimension of material order by characterizing the electronic structure characteristics of the conjugated system in carbon materials. The 2G peak is located at about 1620 cm -1 Wave number area, derived from sp 2 The intensity of the higher-order vibration modes of the hybrid carbon atoms in the plane or out-of-plane vibration modes is related to the degree of electron delocalization of the carbon layer conjugated system. 2G / I G The ratio reflects the conjugation integrity of the C=C bond in the carbon layer and the strength of the interlayer electronic interaction. When the ratio approaches 0.2, it indicates that the material has significant conjugation defects or interlayer stacking disorder, while when it is close to 0.8, it shows a highly delocalized π electron system and interlayer coupling.

[0054] Technical solution passed the qualification I2G / I G The ratio range solves the problem that the integrity of the conjugated system in traditional carbon materials is difficult to quantify and control. Too low a ratio (<0.2) corresponds to conjugated breaks in the carbon layers or interlayer stacking dislocations, resulting in increased resistance to electron transfer; too high a ratio (>0.8) may be due to strong interlayer coupling caused by excessive graphitization, which inhibits the exposure of catalytic active sites. The ratio range of 0.2~0.8 indicates that the material has a moderate conjugated defect density and interlayer interaction. This structural characteristic forms a balance at the atomic scale: moderate conjugated defects provide catalyst anchoring sites and enhance the dispersion stability of platinum particles; while limited interlayer coupling maintains the efficiency of electron transfer between carbon layers and avoids pore closure caused by excessive graphitization. This parameter is closely related to the G peak position (1580~1590 cm -1 )、d 002 The spacing (<0.355 nm) forms a multi-dimensional synergistic control to jointly construct a carbon support with both defect activity and structural stability, thereby delaying the oxidative corrosion process of the carbon matrix under the high-potential cycling conditions of the fuel cell, while maintaining the efficient charge transfer capability of the catalytic reaction interface.

[0055] In some embodiments, the carbon material has a Dv50 particle size of 20 nm to 1000 nm. For example, the Dv50 particle size of the carbon material can be 20 nm, 100 nm, 200 nm, 300 nm, 400 nm, 500 nm, 600 nm, 700 nm, 800 nm, 900 nm, 1000 nm, and other typical but non-limiting values.

[0056] An embodiment of the present invention also proposes a method for preparing a carbon material for a catalyst carrier, comprising the following steps: carbonizing an organic carbon source at 800°C to 1500°C in an inert atmosphere for 0.5h to 8h to obtain an intermediate A; subjecting the intermediate A to a pore-forming treatment at 400°C to 600°C in a mixed atmosphere of an activated gas and an inert gas for 0.5h to 5h to form a porous product; crushing the porous product into nano-scale particles; and graphitizing the nano-scale particles to obtain a carbon material.

[0057] This preparation method uses the "carbonization-pore formation-crushing-graphitization" process to synergistically control the structural properties of carbon materials. First, the organic carbon source is treated with high-temperature carbonization to form an initial graphite microcrystalline structure, laying the foundation for subsequent graphitization; then, the intermediate is treated with activated gas to form pores within a specific temperature range to form a porous structure to increase the specific surface area. "Activated gas" refers to the gaseous medium that participates in the chemical etching of the carbon skeleton during the pore formation stage. It selectively removes disordered structural components in the carbon material through oxidation or gasification reactions, forming a pore network in the gaps between the microcrystalline; then, the product is controlled to a nanoscale size through crushing treatment, which not only avoids excessive grain growth and pore closure during the subsequent high-temperature graphitization process, but also improves the dispersibility of the material; finally, through graphitization treatment, the order of the carbon layer is improved while maintaining the pore structure, achieving a balance between high specific surface area and high degree of graphitization. The temperature range, treatment time and gas environment selection of each step jointly ensure the synergistic optimization of the material's grain size, pore structure and order.

[0058] In some embodiments, the organic carbon source includes at least one of phenolic resin, polyimide, polystyrene, lignin, coal tar, asphalt, benzopyrene, polyacrylonitrile, polyvinyl alcohol, polyethylene, polyvinylidene chloride, cellulose, carboxymethyl cellulose, citric acid, melamine, nitroethylcarbazole, and thiophene.

[0059] By limiting the type of organic carbon source, the aromatization ability of the precursor is enhanced. The selected materials all contain benzene rings, conjugated structures, or cyclizable functional groups, which promote the formation of graphite microcrystals during subsequent high-temperature treatment. Alternatively, they contain O, N, and S heteroatoms, which promote dehydrogenative cyclization during carbonization, further facilitating the formation of aromatic structures (aromatization). Aromatic polymers such as phenolic resins, polyimides, and polystyrene, whose benzene rings and conjugated systems form condensed aromatic hydrocarbon fragments during the initial carbonization phase, promote the oriented growth of graphite microcrystals. Nitrogen / oxygen-containing linear polymers such as polyacrylonitrile and cellulose generate graphene-like fragments through dehydrogenative cyclization during pyrolysis. The released heteroatoms (N / O) act as pore-forming agents to promote micropore formation. Polycyclic aromatic hydrocarbon mixtures such as coal tar and pitch form ordered carbon layer precursors through molecular planar stacking, lowering the activation energy for graphitization.

[0060] In some embodiments, the volume ratio of the activated gas to the inert gas is 5:95 to 10:90; the activated gas includes at least one of H2O, O2, O3, CO2, and air.

[0061] As an example, the volume ratio of the activated gas to the inert gas can be typical but non-limiting values such as 5:95, 6:94, 7:93, 8:92, 9:91, and 10:90. The volume ratio of the activated gas to the inert gas is controlled to be 5:95 to 10:90, which can form pores through oxidation during the pore-forming stage at 400°C to 600°C, while avoiding excessive oxidation that damages the carbon skeleton structure. Heat treatment in a mixed atmosphere of the above-mentioned activated gas and inert gas can remove uncondensed aromatic hydrocarbon fragments, oxidize and form pores in the material structure, and obtain a highly porous carbon material, and no metal contamination is generated during the pore-forming process.

[0062] In some embodiments, the nanoparticles have a particle size of 20 nm to 1000 nm. Crushing the porous product into 20-1000 nm nanoparticles not only maintains the pore structure during graphitization, but also allows for precise control of the grain sizes La and Lc by limiting the space for grain growth. This particle size range also ensures good dispersibility, facilitating uniform distribution of platinum particles during subsequent catalyst loading and providing abundant reaction transport pathways during the catalytic reaction.

[0063] In some embodiments, the graphitization treatment temperature is 1800° C. to 2800° C., and the treatment time is 0.5 h to 3 h.

[0064] By controlling the graphitization treatment temperature between 1800°C and 2800°C, the carbon material can be prompted to form a short-range highly ordered graphite microcrystalline structure at high temperature, but avoid excessive increase in carbon grain size (La, Lc) due to excessive temperature, which in turn causes pore collapse or decrease in specific surface area. The treatment time is limited to 0.5 hours to 3 hours, which can not only fully order the carbon layer structure, but also prevent the closure of grain gaps caused by long-term high-temperature treatment, and maintain a high level of grain gap Φ. The coordinated control of temperature and time not only achieves the high degree of order represented by the shift of the G peak to low wavenumbers (1580~1590cm⁻¹) in the Raman spectrum of carbon materials, but also retains a high specific surface area (100~1200m 2 / g) and pore structure, thus forming a balance between grain size and pore distribution at the microscopic level.

[0065] An embodiment of the present invention further provides a catalyst comprising a carbon support and platinum particles supported on the carbon support, wherein the carbon support comprises the aforementioned carbon material for a catalyst support, or a carbon material obtained by the aforementioned method for preparing the carbon material for a catalyst support.

[0066] The above-mentioned carbon carrier (carbon material) has a high specific surface area, suitable grain spacing and graphitization order. Therefore, when platinum particles are loaded on the carbon carrier, the nanoscale pores and high surface active sites can disperse the particle size of the platinum particles and provide abundant catalytic reaction transmission channels. At the same time, the ordered carbon layer structure enhances the conductivity and durability of the carrier, forming a stable catalyst system.

[0067] In some embodiments, based on 100% by mass of the catalyst, the mass percentage of the platinum particles in the catalyst is 20% to 60%.

[0068] The "mass percentage of platinum particles in the catalyst" here refers to the platinum loading.

[0069] In some embodiments, the average particle size of the platinum particles is 1 nm to 5 nm.

[0070] The carbon support of the embodiment of the present application (the carbon material used for the catalyst support) has a rich micro-mesoporous structure. As a catalytic support, the particle size distribution of the catalytically active metal can be controlled to be 1-5 nm, and a platinum loading of 20-60% can be achieved, with an electrochemically active area (ECSA) of >80 m 2 / g-Pt‌, can be used to prepare highly active catalysts. Among them, the electrochemical active surface area (ECSA) is a parameter used to describe the active surface area of a catalyst, especially a precious metal catalyst (such as platinum Pt). In catalytic reactions, the effective active area of a catalyst has a direct impact on its performance: generally speaking, the larger the active area, the higher the efficiency of the catalyst. ECSA>80 m 2 / g-Pt means that the electrochemical active area per gram of platinum (Pt) is greater than 80 square meters. Here, “m 2 " / g-Pt" is a unit representing square meters per gram of platinum, used to standardize the specific surface area of different samples or materials, allowing the activity of different catalysts to be compared. This value reflects the effective active surface area that a catalyst can provide using its mass and is one of the important indicators for evaluating catalyst performance.

[0071] An embodiment of the present invention further provides a fuel cell, including a catalyst layer, wherein the catalyst layer includes the above-mentioned catalyst.

[0072] The catalyst layer of the fuel cell uses the above catalyst, which uses a short-range highly ordered and high specific surface area carbon material as a carrier to load platinum particles. The carbon material can pass through a high specific surface area (100-1200m 2 / g) provides sufficient platinum particle dispersion sites and catalytic reaction transmission channels, and can also be achieved through high graphitization order (d 002<0.355nm) inhibits corrosion of the carbon layer. Platinum particles with a particle size of 1-5nm can be loaded into the pores of the carrier surface, avoiding the problem of platinum particles being embedded deep in the pores of the material in traditional microporous structures. The closed pore structure prevents the catalyst from contacting the reactants, resulting in active site deactivation, ultimately achieving stable operation of the fuel cell.

[0073] The following describes the details in conjunction with specific embodiments.

[0074] Example 1 This embodiment provides a carbon material, and a method for preparing the carbon material comprises the following steps: S1: Place polystyrene in a drum continuous carbonization furnace and carbonize it at 800°C for 8 h under a nitrogen atmosphere to obtain intermediate A; S2: Intermediate A was treated in a H2O / N2 mixed atmosphere with a volume ratio of 5:95 at 500°C for 0.5h to form a porous product; S3: The porous product was placed in a planetary ball mill and ground into particles with an average particle size of 500 nm; S4: The nanoparticles were placed in a graphitization furnace at 2200° C. for 0.5 h.

[0075] The carbon material has a grain interstitial density of 54% and a specific surface area of 800 m 2 / g, G peak position 1584.3cm -1 , I 2G / I G =0.69,La=2.1nm,d 002 =0.344nm, Lc=1.5nm.

[0076] Example 2 This embodiment provides a carbon material, and a method for preparing the carbon material comprises the following steps: S1: Place polyvinylidene chloride resin in a carbonization furnace and carbonize it at 1200°C for 2 hours under a nitrogen atmosphere to obtain intermediate A; S2: The intermediate A was treated in an O2 / N2 mixed atmosphere with a volume ratio of 10:90 at 500 °C for 5 h to form a porous product; S3: The porous product is crushed into nanoparticles with an average particle size of 40 nm by an ultrafine powder grinder; S4: The nanoparticles were placed in a graphitization furnace at 1800°C for 2 h.

[0077] The carbon material has a grain interstitial density of 93% and a specific surface area of 1200 m 2 / g, G peak position 1589.2cm -1 , I 2G / I G =0.78,La=2.4nm,d002 =0.352nm, Lc=1.8nm.

[0078] Example 3 This embodiment provides a carbon material, and a method for preparing the carbon material comprises the following steps: S1: Carboxymethyl cellulose is placed in a kiln and carbonized at 1000°C for 2 h under a nitrogen atmosphere to obtain intermediate A; S2: The intermediate A was treated in an O2 / N2 mixed atmosphere with a volume ratio of 5:95 at 600 °C for 3 h to form a porous product; S3: placing the porous product into a sand mill and grinding it into nanoparticles with an average particle size of 200 nm; S4: The nanoparticles were placed in a graphitization furnace at 2400°C for 2 h.

[0079] The carbon material has a grain spacing of 80% and a specific surface area of 420 m 2 / g, G peak position 1583.6cm -1 , I 2G / I G =0.47,La=5.5nm,d 002 =0.343nm, Lc=4.6nm.

[0080] Example 4 This embodiment provides a carbon material, and a method for preparing the carbon material comprises the following steps: S1: Carboxymethyl cellulose was placed in a carbonization furnace and carbonized at 800 °C for 2 h under a nitrogen atmosphere to obtain intermediate A; S2: The intermediate A was treated in an O2 / N2 mixed atmosphere with a volume ratio of 5:95 at 400 °C for 0.5 h to form a porous product; S3: placing the porous product into a sand mill and grinding it into nanoparticles with an average particle size of 200 nm; S4: The nanoparticles were placed in a graphitization furnace at 2000°C for 2 h.

[0081] The carbon material has a grain interstitial density of 44% and a specific surface area of 410 m 2 / g, G peak position 1584.0cm -1 , I 2G / I G =0.42,La=3.9nm,d 002 =0.345nm, Lc=2.0nm.

[0082] Example 5 This embodiment provides a carbon material, and a method for preparing the carbon material comprises the following steps: S1: Coal tar is atomized and carbonized in a fluidized bed under nitrogen atmosphere at 1500°C for 1 h to obtain intermediate A; S2: The intermediate A was treated in an O3 / N2 mixed atmosphere with a volume ratio of 10:90 at 600 °C for 2 h to form a porous product; S3: The porous product is dispersed into nanoparticles with an average particle size of 500 nm by a cyclone separator; S4: The nanoparticles were placed in a graphitization furnace at 2800°C for 3 h.

[0083] The carbon material has a grain spacing of 37% and a specific surface area of 100 m 2 / g, G peak position 1581.0cm -1 , I 2G / I G =0.22,La=13.0nm,d 002 =0.343nm, Lc=7.1nm.

[0084] Example 6 This embodiment provides a carbon material, and a method for preparing the carbon material comprises the following steps: S1: Place polyvinylidene chloride resin in a kiln and carbonize it at 1100°C for 2 hours under a nitrogen atmosphere to obtain intermediate A; S2: The intermediate A was treated in an O2 / N2 mixed atmosphere with a volume ratio of 5:95 at 600 °C for 3 h to form a porous product; S3: The porous product is placed in an ultrafine powder grinder and crushed into nanoparticles with an average particle size of 100 nm; S4: The nanoparticles were placed in a graphitization furnace at 2200°C for 3 h.

[0085] The carbon material has a grain interstitial density of 49% and a specific surface area of 380 m 2 / g, G peak position 1582.5cm -1 , I 2G / I G =0.44,La=4.5nm,d 002 =0.345nm, Lc=2.5nm.

[0086] Example 7 This embodiment provides a carbon material, and a method for preparing the carbon material comprises the following steps: S1: Place polystyrene in a carbonization furnace and carbonize it at 1300°C for 2 h under a nitrogen atmosphere to obtain intermediate A; S2: The intermediate A was treated in an O2 / N2 mixed atmosphere with a volume ratio of 10:90 at 500 °C for 1 h to form a porous product; S3: placing the porous product into a sand mill and grinding it into nanoparticles with an average particle size of 500 nm; S4: The nanoparticles were placed in a graphitization furnace at 2500° C. for 0.5 h.

[0087] The carbon material has a grain interstitial density of 53% and a specific surface area of 139 m 2 / g, G peak position 1581.7cm -1 , I 2G / I G =0.30,La=9.5nm,d 002 =0.344nm, Lc=12.8nm.

[0088] Comparative Example 1 Comparative Example 1 provides a carbon material, the preparation method of which comprises the following steps: S1: crushing natural graphite into nanoparticles with an average particle size of 1200 nm; S2: The nanoparticles were placed in a graphitization furnace at 2200°C for 3 h.

[0089] The carbon material has a grain spacing of 27% and a specific surface area of 76m 2 / g, G peak position 1578.6cm -1 , I 2G / I G =0.14,La=15.6nm,d 002 =0.339nm, Lc=5.3nm.

[0090] Comparative Example 2 This embodiment provides a carbon material, and a method for preparing the carbon material comprises the following steps: S1: Coal tar is placed in a kiln and carbonized at 1500°C for 2 h under a nitrogen atmosphere to obtain intermediate A; S2: The intermediate A was treated in an O2 / N2 mixed atmosphere with a volume ratio of 5:95 at 400 °C for 0.5 h to form a porous product; S3: The porous product is placed in a ball mill and ground into nanoparticles with an average particle size of 500 nm; S4: The nanoparticles were placed in a graphitization furnace at 2900°C for 3 h.

[0091] The carbon material has a grain spacing of 28% and a specific surface area of 41m 2 / g, G peak position 1579.8cm -1 , I 2G / I G =0.19,La=21.2nm,d 002 =0.342nm, Lc=15.4nm.

[0092] Comparative Example 3 This embodiment provides a carbon material, and a method for preparing the carbon material comprises the following steps: S1: Carboxymethyl cellulose was placed in a kiln and carbonized at 800 °C for 2 h under a nitrogen atmosphere to obtain intermediate A; S2: Intermediate A was treated in an O2 / N2 mixed atmosphere with a volume ratio of 5:95 at 400 °C for 2 h to form a porous product; S3: The porous product is placed in an ultrafine grinder and ground into nanoparticles with an average particle size of 500 nm; S4: The nanoparticles were placed in a graphitization furnace at 1700°C for 1 h.

[0093] The carbon material has a grain interstitial density of 29% and a specific surface area of 700 m 2 / g, G peak position 1590.4cm -1 , I 2G / I G =0.82,La=1.3nm,d 002 =0.363nm, Lc=1.0nm.

[0094] Material performance testing In order to verify the progress of the examples of the present application, the samples of the examples and comparative examples were tested as follows: 1. Specific surface area S BET Test Referring to GB / T 19587-2017, the nitrogen adsorption specific surface area analysis test method was used for testing, and the BET (Brunauer Emmett Teller) method was used for calculation. Specifically, after measuring the adsorption amount of gas on the solid surface at different relative pressures, the monolayer adsorption amount of the sample was obtained based on the Brunauer-Emmett-Teller adsorption theory and its formula (BET formula), thereby calculating the specific surface area of the material.

[0095] 2. Raman spectroscopy Refer to GB / T 30544.6-2016 to test and analyze the G peak, D peak, 2G peak, I peak of carbon materials 2G / I G and other parameters.

[0096] 3. Interplanar spacing The interplanar spacing of carbon materials was measured using X-ray powder diffractometer (XRD, instrument model: Bruker D8 ADVANCE). 002The target material is Cu Kα, the test voltage is 40KV, the test current is 35mA, the scanning angle range is 10° to 90°, the scanning rate is 0.02° / s, and the strongest diffraction peak intensity is required to be greater than 10,000, in counts. The collected XRD spectrum is refined using Fullprof software to determine the phase structure. The diffraction angle position of the C{002} crystal plane is measured by XRD powder diffraction, and the Bragg diffraction formula (Bragg diffraction formula) 2d 002 sinθ=λK to obtain the interplanar spacing d of carbon materials 002 .

[0097] 4. Graphite crystallite grain size La and longitudinal stacking height Lc 20 carbon particles were randomly obtained and tested by Raman spectroscopy (Raman laser wavelength λ = 514 nm). The ratio of the peak area ID of the carbon characteristic peak of the carbon particles to the peak area IG of the graphite characteristic peak was measured. The value of ID / IG was Rn, n = 1, 2, 3...20; the ratio of the peak area ID of the carbon characteristic peak of the carbon particles to the peak area IG of the graphite characteristic peak was Rn, n = 1, 2, 3...20; D / I G The average value of is R; ; ; Where, the X-ray wavelength λ = 0.15406 nm, β is the half-maximum width of the (002) crystal plane diffraction peak, and ϴ is the diffraction angle of the (002) crystal plane.

[0098] 5.Dv50 particle size The Dv50 particle size of a carbon material is well known in the art and represents the particle size at which the cumulative volume distribution percentage of the material reaches 50%. It can be measured using instruments and methods known in the art. For example, it can be conveniently measured using a laser particle size analyzer, as described in GB / T 19077-2016, "Particle Size Distribution Laser Diffraction Method." The testing instrument can be a Mastersizer 3000 laser particle size analyzer available from Malvern Instruments Ltd., UK.

[0099] 6. Characterization of carbon material morphology Carbon particles were dispersed in ethanol, drop-coated on a copper grid, and observed after drying. The morphology and size of the samples were observed using a FEI Tecnai G2F30 transmission electron microscope at an accelerating voltage of 120 kV.

[0100] 7. Total metal content Referring to the national standard GB / T 24533-2019 lithium-ion battery graphite negative electrode materials, the samples were digested in a high-temperature and high-pressure closed environment of a microwave digester, and the content of each element was tested by ICP-OES.

[0101] Battery performance test 1. Dissolve chloroplatinic acid in ethylene glycol and add it dropwise to the carbon material prepared in the above examples and comparative examples with vigorous stirring. After drying, heat and reduce it in a mixture of hydrogen and argon with a volume ratio of 1:9 at 300°C for 90 minutes. Then disperse the carbon material in water, add H2PtCl6 and formic acid, stir for 5 hours, filter, wash, and dry to obtain a platinum-carbon catalyst. 10g of the catalyst sample was digested with aqua regia, filtered (if any residue was present), and the volume was fixed. The platinum loading of the platinum-carbon catalyst was tested by ICP-OES (inductively coupled plasma optical emission spectrometry).

[0102] 2. Half-cell ECSA test method: Weigh 200 mg of catalyst and add 5% Nafion solution, deionized water and isopropanol in sequence. Ultrasonic dispersion is used to obtain a uniform slurry. The catalyst loading on the electrode surface is 50 μg / cm 2 ~200 μg / cm 2 An appropriate amount of the dispersed slurry was evenly added dropwise to the surface of a smooth, clean disk electrode in two separate batches. After drying, it served as the working electrode. The electrodes were placed in an electrolytic cell to form a three-electrode system. The reference electrode was a reversible hydrogen electrode (RHE), the counter electrode was a large-area Pt sheet, and the electrolyte was a saturated 0.1 mol / L HClO₄ solution.

[0103] Cyclic voltammetry was performed using a potentiostat. Cyclic voltammetry curves were tested by first activating the catalyst at a scan rate of 20 mV / s until the hydrogen desorption peak area no longer increased. Five cycles were then scanned at 20 mV / s over a potential range of 0.05 V to 1.1 V vs RHE. The stabilized cyclic voltammetry curve was selected and the hydrogen desorption peak (0.05 V to 0.4 V vs RHE) was integrated to obtain the area S. The electrochemically active area (ECSA) was then calculated using the formula.

[0104] Calculate ECSA according to the formula: Where S is the integrated area of the hydrogen desorption / adsorption peak (A*V), and C is the charge constant of hydrogen adsorption on the smooth Pt surface (0.21 mC / cm 2 ), v is the scanning rate (mV / s), and M is the mass of Pt on the working electrode (g).

[0105] 3. Half-cell durability test method: Under 65°C air conditions, maintain 0.9V for 3s and 0.65V for 2s as one square wave cycle. Test the ECSA retention rate after 50,000 cycles.

[0106] Performance Results Table 1

[0107] Table 2

[0108] The physical and chemical characteristics of Table 1 and the performance data of Table 2 show that the carbon materials of Examples 1-3 meet the specific surface area (400-1200 m 2 / g), La (2-6nm), Lc (1.5-6nm) and grain spacing (50-95%) and other core parameter requirements, achieving catalyst ECSA ≥ 90 m 2 / g-Pt effect, the ECSA retention rate is above 80% after 50,000 cycles of durability. It is much better than the comparative example 3 (700m 2 / g specific surface area, La = 1.3nm, Lc = 1.0nm) with a 59% ECSA retention rate, indicating that the degree of grain ordering (d 002 <0.344 nm, La>5nm, Lc>4nm) inhibits the oxidation of the carbon matrix, breaking through the bottleneck of high activity but low durability of traditional carbon black (the retention rate of commercial carbon black is only 55%). This shows that the material has moderate conjugated defects and interlayer coupling, which improves corrosion resistance while maintaining high catalytic activity sites, making it suitable for high-activity scenarios.

[0109] The specific surface area of the carbon material of Example 4 satisfies (400-1200 m 2 / g), La (2-13nm), Lc (1.5-6nm) and other core parameter requirements, but the interplanar spacing is less than 50%. Although the ECSA retention rate is above 80% after 50,000 cycles of durability, the ECSA is less than 90 m 2 / g-Pt, that is, the low grain spacing limits the activity.

[0110] The carbon materials of Examples 5-7 meet the specific surface area (100-400 m 2 / g), La (3.5-13nm), Lc (2-13nm) and interplanar spacing (30%-55%), and achieved catalyst ECSA ≥ 80 m 2 The effect of g-Pt was shown, with an ECSA retention rate exceeding 90% after 50,000 cycles. This indicates that the material's low conjugated defects and moderate interlayer coupling have both high durability and high active sites, making it suitable for corrosion-prone environments.

[0111] Comparative Example 1 has insufficient particle size due to insufficient oxidation of the grains (G peak 1574 cm -1 ,La=15.6nm,I 2G / IG = 0.14) resulting in a specific surface area (91 m 2 / g) and Φ value (34%) are insufficient. Comparative Example 2 is too graphitized (G peak 1579.8 cm -1 , I 2G / I G = 0.19,) resulting in excessive grain growth (La = 21.2nm, Lc = 15.4nm), and a specific surface area (41m 2 / g) and Φ value (28%) are insufficient. Comparative Example 3 has insufficient graphitization degree (G peak 1590.4 cm -1 , I 2G / I G =0.82, d 002 =0.363nm), resulting in insufficient grain size (La=1.8nm, Lc=1.4nm) and Φ value (29%). The low Pt loading and ECSA in Comparative Examples 1 and 2 reveal the limitations of the low intergranular spacing on catalytic performance, which in turn supports the effectiveness of the present invention in resolving technical contradictions through coordinated optimization of structural parameters.

[0112] Figure 3 The Raman spectral characteristics of the carbon material of Example 1 are shown. The figure intuitively supports the core design of the carbon material "high specific surface area and orderly coordinated optimization of graphitization" through spectral data, which is consistent with the structural parameters of Example 1 in Table 1 (such as d 002 =0.344 nm) corroborate each other.

[0113] Figure 4 The microscopic morphology of the carbon material is revealed by a transmission electron microscope image, which intuitively confirms from the nanoscale that the carbon material of the present application has the structural advantage of "graphite microcrystalline porous network".

[0114] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformation made by utilizing the contents of the present invention's description and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields, is included in the patent protection scope of the present invention.

Claims

1. A carbon material for a catalyst support, characterized in that: The carbon material has a graphite microcrystalline structure, and the interplanar spacing d of the graphite microcrystalline measured by X-ray diffraction is 002 <0.355nm, the grain size La of the graphite microcrystal is 2nm~14nm, the longitudinal stacking height Lc of the graphite microcrystal is 1.5nm~13nm, and the specific surface area S of the carbon material is BET 100m 2 / g~1200m 2 / g, and the carbon material satisfies: 30%≤Φ≤95%; Φ is the intergranular spacing of the carbon material, .

2. The carbon material for a catalyst support according to claim 1, wherein The specific surface area S of the carbon material BET 400m 2 / g~1200m 2 / g, La is 2nm~6nm, Lc is 1.5nm~5nm, and the grain spacing Φ is 50%-95%.

3. The carbon material for catalyst support according to claim 1, wherein The specific surface area S of the carbon material BET 100m 2 / g~400m 2 / g, La is 3.5nm~13nm, Lc is 2nm~13nm, and the grain spacing Φ is 30%~55%.

4. The carbon material for a catalyst support according to claim 1, wherein The total metal content of the carbon material is less than 100 ppm, and the metal includes any one or more of Fe, Co, Ni, Cr, Mn, Cu, Al, Zn, Na, K, Ca, and Mg.

5. The carbon material for a catalyst support according to any one of claims 1 to 4, characterized in that The carbon material has a peak G position at 1580 cm in the Raman spectrum. -1 ~1590cm -1 The half-peak width of the G peak is 25 cm -1 ~50cm -1 ; And / or, the intensity ratio of the 2G peak to the G peak of the carbon material in the Raman spectrum is 2G / I G 0.2~0.8; And / or, the Dv50 particle size of the carbon material is 20 nm to 1000 nm.

6. A method for preparing a carbon material for a catalyst support according to any one of claims 1 to 5, characterized in that: The following steps are involved: The organic carbon source is carbonized in an inert atmosphere at 800°C to 1500°C for 0.5h to 8h to obtain intermediate A; The intermediate A is subjected to a pore-forming treatment at 400° C. to 600° C. in a mixed atmosphere of activated gas and inert gas for 0.5 h to 5 h to form a porous product; Crushing the porous product into nano-scale particles; The carbon material is obtained by graphitizing the nano-scale particles.

7. The method for preparing a carbon material for a catalyst support according to claim 6, wherein: The organic carbon source includes at least one of phenolic resin, polyimide, polystyrene, lignin, coal tar, asphalt, benzopyrene, polyacrylonitrile, polyvinyl alcohol, polyethylene, polyvinylidene chloride, cellulose, carboxymethyl cellulose, citric acid, melamine, nitroethylcarbazole, and thiophene; And / or, the volume ratio of the activated gas to the inert gas is 5:95 to 10:90; the activated gas includes at least one of H2O, O2, O3, CO2, and air; and / or, the particle size of the nanoscale particles is 20 nm to 1000 nm; And / or, the temperature of the graphitization treatment is 1800° C. to 2800° C., and the treatment time is 0.5 h to 3 h.

8. A catalyst, characterized in that It comprises a carbon support and platinum particles supported on the carbon support, wherein the carbon support comprises the carbon material for a catalyst support according to any one of claims 1 to 5, or a carbon material prepared by the method for preparing the carbon material for a catalyst support according to any one of claims 6 to 7.

9. The catalyst according to claim 8, characterized in that Based on the mass of the catalyst being 100%, the mass percentage of the platinum particles in the catalyst is 20% to 60%; And / or, the average particle size of the platinum particles is 1 nm to 5 nm.

10. A fuel cell, characterized in that: Comprising a catalyst layer, the catalyst layer comprising the catalyst according to claim 8 or 9.

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