One-dimensional platinum-based catalysts, methods of making and using the same

Abstract

The application belongs to the technical field of catalysts, and provides a one-dimensional platinum-based catalyst, a preparation method and application thereof. The one-dimensional platinum-based catalyst has a nanorod structure and is a platinum-tellurium-bismuth catalyst or a bismuth-doped platinum-tellurium catalyst. The preparation method comprises the following steps: (1) in the presence of a dispersing agent, performing a hydrothermal reaction on a platinum precursor, a tellurium precursor, a bismuth precursor and ascorbic acid in an aqueous solvent to form a platinum-tellurium-bismuth ternary heterogeneous phase alloy; (2) loading the platinum-tellurium-bismuth ternary heterogeneous phase alloy on a carbon material to obtain a platinum-tellurium-bismuth catalyst; optionally, the method further comprises the following step: (3) performing acid treatment on the platinum-tellurium-bismuth catalyst obtained in step (2) to dealloy, thereby obtaining a bismuth-doped platinum-tellurium catalyst. The catalyst exhibits excellent electrocatalytic activity and stability in a formic acid oxidation reaction.

Description

Technical Field

[0001] This invention belongs to the field of catalyst technology, specifically, it provides a one-dimensional platinum-based catalyst, its preparation method, and its application. Background Technology

[0002] Against the backdrop of increasingly severe global energy shortages and environmental pollution, significant progress has been made in the research and development of fuel cell technology. Among them, the direct formic acid fuel cell (DFAFC) is considered one of the most promising energy conversion devices due to its advantages such as high safety, high energy density, and high energy conversion efficiency. However, the application of DFAFC is largely limited by the performance of its anolyte formic acid oxidation reaction (FAOR) catalyst.

[0003] Currently, platinum (Pt)-based catalysts have attracted much attention in various catalytic reactions, especially in electrocatalysis, due to their excellent catalytic activity and stability. However, in FAOR (Fuel-Assisted Reactor) systems, while pure Pt catalysts exhibit high electrocatalytic activity, their surfaces are susceptible to indirect formic acid decomposition, generating and adsorbing carbon monoxide (CO), leading to catalyst poisoning and deactivation. To address these limitations, developing platinum-based alloy catalysts has become an effective strategy. This method involves introducing other metal elements to reduce the amount of platinum used and improve electrochemical activity and resistance to poisoning. However, in the acidic environment of the battery, the introduced metal components are prone to corrosion and dissolution, leading not only to catalyst structural damage and a continuous decline in activity but also limiting their long-term stability.

[0004] In addition, high-performance DFAFC anode catalysts must meet multiple requirements simultaneously: on the one hand, they should have high electrocatalytic activity and preferentially promote the direct oxidation pathway of formic acid, thereby ensuring energy conversion efficiency while avoiding CO generation at the source; on the other hand, they should have excellent resistance to poisoning and be able to effectively inhibit the adsorption and accumulation of toxic intermediates such as CO on the catalyst surface, thereby ensuring their stability in long-term operation.

[0005] Therefore, in order to meet the requirements of catalysts used in the anode reaction and membrane electrode application environment of direct formic acid fuel cells, it is urgent to develop new platinum-based catalysts. Summary of the Invention

[0006] The present invention aims to provide a one-dimensional platinum-based catalyst, its preparation method, and its application. The one-dimensional heterogeneous platinum-based catalyst prepared by the present invention is a carbon-supported catalyst, which exhibits excellent electrocatalytic activity and stability in the formic acid oxidation reaction.

[0007] In a first aspect, the present invention provides a method for preparing a one-dimensional platinum-based catalyst, comprising: (1) In the presence of a dispersant, platinum precursor, tellurium precursor, bismuth precursor and ascorbic acid are subjected to a hydrothermal reaction in an aqueous solvent to form a platinum-tellurium-bismuth ternary heterostructure alloy; (2) The platinum-tellurium-bismuth ternary heterostructure alloy is loaded onto a carbon material to obtain a platinum-tellurium-bismuth catalyst; Optionally, the preparation method further includes: (3) The platinum tellurium bismuth catalyst obtained in step (2) is subjected to acid treatment to de-alloy, and bismuth-doped platinum tellurium catalyst is obtained.

[0008] The one-dimensional platinum-based catalyst prepared in this invention is a platinum with a nanorod structure. tellurium Bismuth ternary catalysts or bismuth-doped platinum A tellurium binary catalyst. On the one hand, the introduction of bismuth modulates the electronic structure of platinum through electronic effects, significantly weakening its adsorption of CO intermediates and thus enhancing its resistance to poisoning. Tellurium not only dominates the formation of one-dimensional nanorod structures in conjunction with the precursor, ascorbic acid, and dispersant, but also provides oxygen-containing species during the reaction, promoting the oxidative removal of adsorbed CO. The synergistic effect among the three components effectively enhances the CO poisoning resistance of the platinum-based catalyst. On the other hand, the introduction of carbon support effectively inhibits the aggregation of one-dimensional nanorods, ensuring sufficient exposure of active sites, while constructing an efficient electron conduction network to promote charge transport during the reaction. The synergistic effect of these two aspects enables the catalyst to exhibit both high catalytic activity and long-term stability in the formic acid oxidation reaction. Furthermore, acid treatment of platinum... tellurium Controllable dealloying of bismuth catalysts can effectively increase the surface roughness of nanorods, improve the density of active sites, and optimize the surface chemical composition, thereby further enhancing catalytic activity and selectivity for the direct pathway of formic acid oxidation.

[0009] In a second aspect, the present invention provides a one-dimensional platinum-based catalyst prepared by the preparation method described in the first aspect of the present invention.

[0010] Thirdly, the present invention provides the application of the one-dimensional platinum-based catalyst described in the second aspect of the present invention in the formic acid oxidation reaction.

[0011] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0012] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1Transmission electron microscopy (TEM) images of the platinum-based catalysts and commercial platinum-carbon catalysts prepared in Examples 1-15. Figure 2 Polycrystalline X-ray diffraction (XRD) patterns of the platinum-based catalysts prepared in Examples 1-6; Figure 3 Cyclic voltammograms (CVs) of the platinum-based catalysts prepared in Examples 1-15 and the commercial platinum-carbon catalysts were tested in 0.5 mol / L sulfuric acid (solvent I). Figure 4 Cyclic voltammograms, current-time curves, and bar charts comparing the selectivity, stability, and anti-poisoning properties of each catalyst were obtained before and after CO introduction in a mixed electrolyte (solvent II) of 0.5 mol / L sulfuric acid and 0.5 mol / L formic acid for the platinum-based catalysts prepared in Examples 1-6 and commercial platinum-carbon catalysts. Figure 5 Cyclic voltammograms and current-time curves of the platinum-based catalysts prepared in Examples 7-15 and the commercial platinum-carbon catalysts were measured in a mixed electrolyte of 0.5 mol / L sulfuric acid and 0.5 mol / L formic acid. Figure 6 The graphs show the polarization curves, power density curves, and peak power density histograms of the platinum-based catalyst and the commercial platinum-carbon catalyst in Example 5 on the membrane electrode assembly of a direct formic acid fuel cell. Detailed Implementation

[0013] The embodiments of the present invention are described in detail below. The embodiments described below are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0014] The "scope" disclosed in this invention is defined in the form of a lower limit and / or an upper limit, whereby a given scope is defined by selecting a lower limit and / or an upper limit. This scope may or may not include endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form an undefined scope, and any lower limit can be combined with other lower limits to form an undefined scope, similarly, any upper limit can be combined with any other upper limit to form an undefined scope. Furthermore, each individually disclosed point or single value can itself serve as a lower or upper limit and can be combined with any other point or single value, or with other lower or upper limits, to form an undefined scope.

[0015] Unless otherwise specified, all embodiments and optional embodiments of the present invention may be combined with each other to form new technical solutions, and such technical solutions should be considered to be included in the disclosure of the present invention.

[0016] In this invention, the terms “first,” “second,” and “third,” etc., are used only for distinction and ease of description, and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated.

[0017] A first aspect of the present invention provides a method for preparing a one-dimensional platinum-based catalyst, the method comprising: (1) In the presence of a dispersant, platinum precursor, tellurium precursor, bismuth precursor and ascorbic acid are subjected to a hydrothermal reaction in an aqueous solvent to form a platinum-tellurium-bismuth ternary heterostructure alloy; (2) The platinum-tellurium-bismuth ternary heterostructure alloy is loaded onto a carbon material to obtain a platinum-tellurium-bismuth catalyst; Optionally, the preparation method further includes: (3) The platinum tellurium bismuth catalyst obtained in step (2) is subjected to acid treatment to de-alloy, and bismuth-doped platinum tellurium catalyst is obtained.

[0018] This invention successfully constructed a ternary platinum-based catalyst with a nanorod-like structure (specifically, a sea cucumber-like nanorod structure) through the synergistic regulation of dimensionality, composition, and crystal phase. Compared with zero-dimensional nanostructures, one-dimensional nanorods exhibit several structural advantages: First, their specific growth mode promotes the preferential exposure of low-energy crystal planes and provides abundant active sites on a one-dimensional scale, which helps to improve catalytic performance; second, the one-dimensional continuous structure reduces the number of grain boundaries and interparticle gaps, thereby promoting electron transport and improving conductivity and mass transfer efficiency; third, this structure has higher stability and can effectively suppress the aggregation and ripening of nanoparticles during the reaction process, thus enhancing catalytic durability. Furthermore, this invention further optimizes catalyst performance through composition and crystal phase regulation: by introducing tellurium, bismuth, and platinum elements to form a ternary alloy, the electronic structure of platinum can be adjusted, enhancing its catalytic activity; simultaneously, the design of this heterostructure introduces lattice stress and electronic reconstruction at the interface, generating new active sites and accelerating interfacial charge transfer and reaction kinetics. The synergistic effect of different components and crystal phases at the interface not only improves the electron transfer efficiency but also optimizes the adsorption behavior of reaction intermediates at active sites, thereby improving the overall performance of platinum-based catalysts.

[0019] In step (1), ascorbic acid is used as a reducing agent, which can not only reduce the platinum, tellurium, and bismuth metal ions provided by the precursor to their atomic state, but also guide the atoms to preferentially grow along specific crystal planes, promoting the formation of rod-shaped nanostructures. According to some embodiments, the concentration of ascorbic acid in the aqueous solvent is 5~20 mg / mL, for example 8 mg / mL, 10 mg / mL, 12 mg / mL, 15 mg / mL, 17 mg / mL, 18 mg / mL, 20 mg / mL, etc.

[0020] In step (1), the dispersant adsorbs onto the surface of newly formed nanocrystals through steric hindrance, inhibiting excessive particle growth and aggregation. Preferably, the dispersant is polyvinylpyrrolidone (PVP). The number-average molecular weight of PVP can be 40,000 to 60,000. In addition to its dispersing function, PVP can also act as a morphology control agent, as its molecular chains can selectively adsorb onto specific crystal faces, guiding the directional assembly of precursors during reduction in the liquid phase.

[0021] In some embodiments, the concentration of PVP in the mixture is 15-30 mg / mL, such as 15 mg / mL, 18 mg / mL, 20 mg / mL, 25 mg / mL, 28 mg / mL, 30 mg / mL, etc.

[0022] In step (1), the platinum precursor, tellurium precursor, and bismuth precursor are reduced and alloyed together under the action of ascorbic acid during the hydrothermal synthesis process to form a platinum-tellurium-bismuth ternary heterostructure alloy.

[0023] In some embodiments, the platinum precursor is tetraammineplatinum nitrate (Pt(NH3)4(NO3)2), the tellurium precursor is tellurite, preferably potassium tellurite (K2TeO3) and / or sodium tellurite (Na2TeO3), and the bismuth precursor is bismuth oxycarbonate (Bi2O2CO3). Tellurite, under the reducing action of ascorbic acid, can be reduced and self-assembled to form one-dimensional Te nanowires. Under the morphology regulation of the dispersant and the reducing action of ascorbic acid, the platinum and bismuth precursors can be gradually deposited and alloyed along these Te nanowires to form a sea cucumber-like nanorod structure with high surface roughness and abundant heterogeneous interfaces.

[0024] In some embodiments, the amounts of the platinum precursor, tellurium precursor, and bismuth precursor are expressed as a molar ratio of platinum (Pt), tellurium (Te), and bismuth (Bi) of 1:(0.8~1.2):(0.3~1.5), such as 1:0.8:0.3, 1:0.9:0.4, 1:1:0.5, 1:1:0.8, 1:1:1, 1:1:1.3, etc.

[0025] In some embodiments, the concentration of the platinum precursor in the mixed solvent is 1 to 3 mmol / L, for example 1.5 mmol / L, 2 mmol / L, 2.5 mmol / L, 2.8 mmol / L, etc.

[0026] In step (1), the mixed solvent may be composed of water and alcohol. The volume ratio of water to alcohol may be 1:(0.5~2.5), for example 0.5:1, 1:1, 1:1.2, 1:1.5, 1:1.8, 1:2, 1:2.3, 1:2.5, etc., preferably 1:(1.2~2.5).

[0027] As some preferred examples, the alcohol is ethylene glycol. The three precursors—tetraammineplatinum nitrate, tellurite, and bismuth oxycarbonate—all exhibit high solubility in a mixed solvent of water and ethylene glycol, promoting the formation of uniform sea cucumber-shaped platinum-tellurium-bismuth nanorods.

[0028] In step (1), the hydrothermal reaction can be carried out in a high-pressure reactor. According to some embodiments, the temperature of the hydrothermal reaction is 160~210℃. o C, for example, 160 o C, 170 o C, 180 o C, 185 o C, 190 o C, 200 o C, 205 o C, 210 o C, etc., the hydrothermal reaction time can be 3 to 12 hours, for example 3 hours, 5 hours, 7 hours, 8 hours, 10 hours, 12 hours, etc.

[0029] In some implementations, step (1) includes the following steps: (1-1) The platinum precursor, tellurium precursor, bismuth precursor, ascorbic acid, and dispersant are added to the aqueous solvent and ultrasonically dispersed to obtain a mixture. The ultrasonic dispersion conditions can be selected according to the stability of the mixture, generally ensuring that no visible layering or precipitation occurs within 2 hours of standing. Preferably, the ultrasonic dispersion frequency is 25~40 kHz and the time is 0.5~3 hours, for example, 0.5 hours, 1 hour, 2 hours, 3 hours, etc.

[0030] (1-2) The mixture is transferred to a high-pressure reactor for hydrothermal reaction. The resulting product is subjected to solid-liquid separation and a first wash to obtain a platinum-tellurium-bismuth ternary heterostructure alloy. The first wash aims to remove at least part of the dispersant. Preferably, the solvent used is a mixture of ethanol and acetone, wherein the volume ratio of ethanol to acetone is 1:(4~10), such as 1:5, 1:7, 1:8, 1:9, etc. The washing can be performed once or multiple times.

[0031] In step (2), the platinum-tellurium-bismuth ternary heterostructure alloy prepared in step (1) is loaded onto carbon material to prevent the agglomeration of nanorods and ensure the full exposure of active sites.

[0032] In some embodiments, the carbon material may be selected from at least one of conductive carbon black, ordered mesoporous carbon, and nitrogen-doped mesoporous carbon. These types of carbon materials generally possess high conductivity, high specific surface area, and excellent dispersibility, which helps to construct an efficient electron conduction network and improve the overall stability of the catalyst.

[0033] Furthermore, the conductive carbon black is selected from Vulcan XC-72R type toner and / or Ketjen black, preferably Vulcan XC-72R type toner.

[0034] In some embodiments, the mass ratio of the platinum-tellurium-bismuth ternary heterostructure alloy to the carbon support is (1~2):1.

[0035] In some embodiments, the load is applied under ultrasonic conditions, with an ultrasonic frequency of 25-40 Hz and an ultrasonic duration of 1-5 h, such as 1 h, 2 h, 3 h, 5 h, etc.

[0036] In some implementations, step (2) includes the following steps: (2-1) The platinum-tellurium-bismuth ternary heterostructure alloy and the carbon material are added to an alcohol solvent (such as ethanol) and ultrasonically dispersed. (2-2) The product obtained in step (2-1) is subjected to solid-liquid separation to obtain the platinum tellurium bismuth catalyst.

[0037] The preparation method of the present invention may or may not include step (3), but in order to further improve the morphology and component distribution of the platinum-based catalyst, step (3) is preferred. By acid treatment, bismuth and tellurium on the surface of the platinum tellurium bismuth catalyst can be etched away, further roughening the nanorods.

[0038] In some embodiments, nitric acid is used to perform the acid treatment. Preferably, the concentration of the nitric acid is 4~8 mol / L, for example, 4 mol / L, 5 mol / L, 6 mol / L, 8 mol / L, etc., the temperature of the acid treatment is 50~70 °C, for example, 50 °C, 60 °C, 65 °C, 70 °C, etc., and the treatment time is 10~60 min, for example, 10 min, 20 min, 30 min, 50 min, etc.

[0039] In some embodiments, the amount of nitric acid used is 1 to 2 L relative to 1 g of platinum tellurium bismuth catalyst.

[0040] In some implementations, step (3) includes the following steps: (3-1) The platinum tellurium bismuth catalyst is added to nitric acid and the acid treatment is carried out under stirring conditions (e.g., magnetic stirring); (3-2) The product obtained in step (3-1) is subjected to solid-liquid separation and a third wash to obtain the bismuth-doped platinum tellurium catalyst. The third wash is intended to remove residual nitric acid and any dispersants that may be present, and ethanol is the preferred solvent.

[0041] According to some specific embodiments, the method for preparing the one-dimensional platinum-based catalyst of the present invention includes the following steps: S1, platinum precursor, tellurium precursor, bismuth precursor, ascorbic acid and dispersant PVP are added to a mixed solvent of water and alcohol and ultrasonically dispersed to form a uniform mixture. S2, the mixture is transferred to a high-pressure hydrothermal reactor and heated to carry out a hydrothermal reaction. After the reaction is completed, the system is cooled to room temperature, and the solid product is collected by centrifugation. After washing, a PVP-modified platinum-tellurium-bismuth heterophase alloy is obtained. S3, the heterogeneous phase alloy and carbon material obtained in S2 are ultrasonically dispersed in a solvent to achieve carbon loading, and the solid product is collected by centrifugation; S4. The product obtained in S3 is ground to obtain a platinum tellurium bismuth catalyst. Optionally, it also includes: S5, the platinum tellurium bismuth catalyst obtained in S4 is added to an acid solution for acid treatment. The solid product is collected by centrifugation and washed to obtain the bismuth-doped platinum tellurium catalyst.

[0042] A second aspect of the present invention provides a one-dimensional platinum-based catalyst prepared by the preparation method described in the first aspect of the present invention.

[0043] In some embodiments, the one-dimensional platinum-based catalyst is the platinum-tellurium-bismuth catalyst (i.e., the catalyst before acid treatment), with the atomic percentage of platinum being 30% to 45%, the atomic percentage of tellurium being 30% to 45%, and the atomic percentage of bismuth being 12% to 38%, based on the total atomic percentage of platinum, tellurium, and bismuth.

[0044] In other embodiments, the one-dimensional platinum-based catalyst is a bismuth-doped platinum-tellurium catalyst (i.e., an acid-treated catalyst), with the atomic percentage of platinum being 50% to 74%, tellurium being 25% to 47%, and bismuth being 0.05% to 3%, based on the total atomic percentage of platinum, tellurium, and bismuth.

[0045] In this invention, the atomic ratio in the catalyst can be determined by scanning electron microscopy-X-ray energy dispersive spectroscopy (SEM-EDS).

[0046] A third aspect of the invention provides the use of the one-dimensional platinum-based catalyst described in the second aspect of the invention in the formic acid oxidation reaction or in the preparation of a direct formic acid fuel cell.

[0047] In some embodiments, the application in the preparation of direct formic acid fuel cells includes using the one-dimensional platinum-based catalyst to prepare the membrane electrode assembly of the direct formic acid fuel cell.

[0048] The following describes embodiments of the present invention. These embodiments are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0049] The following examples illustrate the platinum-based catalyst and its preparation method of the present invention.

[0050] In the following examples and comparative examples, The number-average molecular weight of polyvinylpyrrolidone was 58,000, and it was purchased from Anaiji Reagent Co., Ltd. The Ketjen Black model is EC600JD, purchased from Suzhou Shengernuo Technology Co., Ltd. The ordered mesoporous carbon was designated CMK-3, and the nitrogen-doped mesoporous carbon was designated NMCS; both were purchased from Jiangsu Xianfeng Nanomaterials Technology Co., Ltd.

[0051] Example 1 S1: Add 10 mg of tetraammineplatinum nitrate, 6.4 mg of potassium tellurite, 3.3 mg of bismuth oxycarbonate, 150 mg of ascorbic acid and 200 mg of polyvinylpyrrolidone to a mixed solvent consisting of 3 mL of water and 7 mL of ethylene glycol, and sonicate at 35 kHz for 2 h to form a homogeneous mixture. S2: The mixture obtained in S1 was transferred to a high-pressure hydrothermal reactor, heated to 200 °C and reacted for 6 h. After the reaction was completed, the system was allowed to cool naturally to room temperature. The product was collected by centrifugation and washed with a mixture of ethanol and acetone in a volume ratio of 1:8 to obtain a PVP-modified platinum-tellurium-bismuth heterophase alloy. S3: Take 5 mg of the product obtained in S2 and add it to 10 mL of ethanol, then add 4.4 mg of Vulcan XC-72R carbon powder, sonicate at 40 kHz for 1 h, and then collect the product by centrifugation; S4: Transfer the product to a mortar and grind it evenly to obtain a platinum tellurium bismuth catalyst, denoted as Cat-1.

[0052] Example 2 The platinum-based catalyst was prepared according to the method of Example 1, except that the amount of bismuth oxycarbonate was adjusted to 6.6 mg, and the prepared platinum-bismuth telluride catalyst was designated as Cat-2.

[0053] Example 3 The platinum-based catalyst was prepared according to the method of Example 1, except that the amount of bismuth oxycarbonate was adjusted to 9.9 mg, and the prepared platinum-bismuth telluride catalyst was designated as Cat-3.

[0054] Comparative Example 1 A platinum-based catalyst was prepared according to the method in Example 1, except that potassium tellurite was not added. The prepared platinum-bismuth catalyst is designated as Cat-D1.

[0055] Comparative Example 2 A platinum-based catalyst was prepared according to the method in Example 1, except that bismuth oxycarbonate was not added. The prepared platinum tellurium catalyst is denoted as Cat-D2.

[0056] Example 4 The platinum tellurium bismuth catalyst was prepared according to S1 to S4 of Example 1.

[0057] S5: The obtained platinum tellurium bismuth catalyst was added to 6 mol / L nitric acid (10 mL) and stirred at 60 °C for 0.5 h. The product was then collected by centrifugation, washed with ethanol, and the bismuth-doped platinum tellurium catalyst was obtained, denoted as Cat-4.

[0058] Example 5 The platinum tellurium bismuth catalyst was prepared according to S1 to S4 of Example 2.

[0059] S5: The obtained platinum tellurium bismuth catalyst was added to 6 mol / L nitric acid (10 mL) and stirred at 60 °C for 0.5 h. The product was then collected by centrifugation, washed with ethanol, and the bismuth-doped platinum tellurium catalyst was obtained, denoted as Cat-5.

[0060] Example 6 The platinum tellurium bismuth catalyst was prepared according to S1 to S4 of Example 3.

[0061] S5: The obtained platinum tellurium bismuth catalyst was added to 6 mol / L nitric acid (10 mL) and stirred at 60 °C for 0.5 h. The product was then collected by centrifugation, washed with ethanol, and the bismuth-doped platinum tellurium catalyst was obtained, denoted as Cat-6.

[0062] Example 7 S1: Add 10 mg of tetraammineplatinum nitrate, 6.4 mg of potassium tellurite, 3.3 mg of bismuth oxycarbonate, 100 mg of ascorbic acid and 150 mg of polyvinylpyrrolidone to a mixed solvent consisting of 3 mL of water and 7 mL of ethylene glycol, and sonicate at 35 kHz for 1.5 h to form a homogeneous mixture. S2: The mixture obtained in S1 was transferred to a high-pressure hydrothermal reactor, heated to 180 °C and reacted for 10 h. After the reaction was completed, the system was allowed to cool naturally to room temperature. The product was collected by centrifugation and washed with a mixture of ethanol and acetone solution with a volume ratio of 1:8 to obtain a PVP-modified platinum-tellurium-bismuth heterophase alloy. S3: Take 5 mg of the product obtained in S2 and add it to 10 mL of ethanol, then add 4.4 mg of Ketjen black, disperse it by ultrasonication at 40 kHz for 1 h, and collect the product by centrifugation; S4: Transfer the product to a mortar and grind it evenly to obtain a platinum tellurium bismuth catalyst; S5: The obtained platinum tellurium bismuth catalyst was added to 6 mol / L nitric acid (10 mL) and stirred at 55 °C for 1 h. The product was then collected by centrifugation, washed with ethanol, and the bismuth-doped platinum tellurium catalyst was obtained, denoted as Cat-7.

[0063] Example 8 The platinum-based catalyst was prepared according to the method of Example 7, except that the amount of bismuth oxycarbonate was adjusted to 6.6 mg. The prepared bismuth-doped platinum tellurium catalyst was designated Cat-8.

[0064] Example 9 The platinum-based catalyst was prepared according to the method of Example 7, except that the amount of bismuth oxycarbonate was adjusted to 9.9 mg. The prepared bismuth-doped platinum tellurium catalyst was designated Cat-9.

[0065] Example 10 S1: Dissolve 10 mg of tetraammineplatinum nitrate, 6.4 mg of potassium tellurite, 3.3 mg of bismuth oxycarbonate, 90 mg of ascorbic acid and 150 mg of polyvinylpyrrolidone in a mixed solvent consisting of 3 mL of water and 7 mL of ethylene glycol, and disperse by ultrasonication at 30 kHz for 2 h to form a homogeneous mixture. S2: The mixture obtained in S1 was transferred to a high-pressure hydrothermal reactor, heated to 200 °C and reacted for 8 h. After the reaction was completed, the system was allowed to cool naturally to room temperature. The product was collected by centrifugation and washed with a mixture of ethanol and acetone in a volume ratio of 1:8 to obtain a PVP-modified platinum-tellurium-bismuth heterophase alloy. S3: Take 5 mg of the product obtained in S2 and add it to 10 mL of ethanol, then add 4.4 mg of ordered mesoporous carbon, disperse it by ultrasonication at 40 kHz for 2 h, and collect the product by centrifugation. S4: The product is transferred to a mortar and ground to obtain a platinum tellurium bismuth catalyst; S5: The obtained platinum tellurium bismuth catalyst was added to 6 mol / L nitric acid (10 mL) and stirred at 60 °C for 0.5 h. The product was then collected by centrifugation, washed with ethanol, and the bismuth-doped platinum tellurium catalyst, denoted as Cat-10, was obtained.

[0066] Example 11 The platinum-based catalyst was prepared according to the method of Example 10, except that the amount of bismuth oxycarbonate was adjusted to 6.6 mg. The prepared bismuth-doped platinum tellurium catalyst was designated as Cat-11.

[0067] Example 12 The platinum-based catalyst was prepared according to the method of Example 10, except that the amount of bismuth oxycarbonate was adjusted to 9.9 mg. The prepared bismuth-doped platinum tellurium catalyst was designated as Cat-12.

[0068] Example 13 S1: Add 10 mg of tetraammineplatinum nitrate, 6.4 mg of potassium tellurite, 3.3 mg of bismuth oxycarbonate, 120 mg of ascorbic acid and 180 mg of polyvinylpyrrolidone to a mixed solvent consisting of 4 mL of water and 6 mL of ethylene glycol, and sonicate at 35 kHz for 1.5 h to form a homogeneous mixture. S2: The mixture obtained in S1 was transferred to a high-pressure hydrothermal reactor, heated to 180 °C and reacted for 10 h. After the reaction was completed, the system was allowed to cool naturally to room temperature. The product was collected by centrifugation and washed with a mixture of ethanol and acetone in a volume ratio of 1:8 to obtain a PVP-modified platinum-tellurium-bismuth heterophase alloy. S3: Take 5 mg of the product obtained in S2 and add it to 10 mL of ethanol, then add 4.4 mg of Ketjen black, disperse it by ultrasonication at 40 kHz for 1 h, and collect the product by centrifugation; S4: Transfer the product to a mortar and grind it evenly to obtain a platinum tellurium bismuth catalyst; S5: The obtained platinum tellurium bismuth catalyst was added to 10 mL of 6 mol / L nitric acid and stirred at 60 °C for 1 h. After the reaction was completed, the product was collected by centrifugation, washed with ethanol, and the bismuth-doped platinum tellurium catalyst, denoted as Cat-13, was obtained.

[0069] Example 14 The platinum-based catalyst was prepared according to the method of Example 13, except that the amount of bismuth oxycarbonate was adjusted to 6.6 mg. The prepared bismuth-doped platinum tellurium catalyst was designated as Cat-14.

[0070] Example 15 The platinum-based catalyst was prepared according to the method of Example 13, except that the amount of bismuth oxycarbonate was adjusted to 9.9 mg. The prepared bismuth-doped platinum tellurium catalyst was designated as Cat-15.

[0071] The following test examples are used to characterize and evaluate the performance of the catalysts in the examples and comparative examples.

[0072] Commercial platinum-carbon catalyst (70 wt% platinum nanoparticles supported on Vulcan XC-72R carbon support) was purchased from Suzhou Shengernuo Technology Co., Ltd.; 5% Nafion solution was purchased from Sigma-Aldrich Ltd.

[0073] Test Example 1: Catalyst Characterization 1. Catalyst elemental analysis The elemental composition of the catalyst samples was analyzed using scanning electron microscopy-X-ray energy-dispersive spectroscopy (SEM-EDS). A Hitachi TM3030 SEM was used in conjunction with an Oxford AZTECONE energy dispersive spectrometer. The testing conditions were: EDX mode, magnification 1000, and resolution approximately 50–200 nm. The atomic proportions of the major elements are shown in Table 1.

[0074] Table 1

[0075] As shown in Table 1, the atomic ratio of platinum, tellurium, and bismuth in catalyst Cat-5 of Example 5 is 66.8:33.1:0.1. Compared with Cat-2 of Example 2, Cat-5, obtained after dealloying, contains bismuth in trace amounts, while the atomic ratio of platinum to tellurium is approximately 2:1. Furthermore, comparing Examples 4 and 6 with Examples 1 and 3 respectively, it is evident that after alloying, bismuth exists in trace amounts, and the atomic ratio of platinum is significantly higher than that of tellurium. Similarly, in catalysts Cat-7 to Cat-15 prepared after dealloying in Examples 7-15, bismuth also exists in trace amounts.

[0076] 2. Catalyst morphology analysis The microstructure of the catalyst was analyzed using a JEOL JEM-1400 transmission electron microscope with an accelerating voltage of 100 kV.

[0077] Figure 1 In the figures, A~O and P are transmission electron microscope images of the catalysts Cat-1 to Cat-15 prepared in Examples 1~15, and the commercial platinum-carbon catalyst, respectively. (Combined with...) Figure 1 It can be seen that, compared with commercial platinum-carbon catalysts (zero-dimensional nanoparticles), catalysts Cat-1 to Cat-15 all exhibit sea cucumber-like nanorod structures with porous and uneven surface features. Among them, the acid-treated catalysts (Cat-4 to Cat-15) are structurally more compact than the untreated catalysts (Cat-1 to Cat-3).

[0078] 3. Catalyst Crystal Phase Analysis Phase analysis of the samples was performed using a Rigaku Smart Lab-SE X-ray powder diffractometer (Japan). The test conditions were as follows: copper target Kα rays were used as the radiation source.

[0079] Figure 2 The X-ray diffraction (XRD) patterns of the catalysts from Examples 1-6 are shown. Figure 2 As can be seen from A to C, the crystal phases of the platinum tellurium bismuth catalysts (Cat-1 to Cat-3) change with increasing bismuth content. At the lowest bismuth content, the characteristic peaks in the catalyst (Cat-1) correspond to the standard crystal phase cards of PtTe2 (JCPDS # No. 88-2277) and Bi2O2CO3 (JCPDS # No. 84-1752), respectively. With increasing bismuth content, characteristic peaks of Bi (JCPDS # No. 44-1246) gradually appear in the catalyst's crystal phase. When the bismuth content is highest, the main characteristic peaks in the catalyst's crystal phase are Bi2O2CO3 and Bi. Figure 2 The D~F figures show the crystal phases of the catalysts after acid treatment. The characteristic peaks of these three catalysts (Cat-4 to Cat-6) all correspond to the standard crystal phase cards of PtTe (JCPDS # No. 89-6166) and Pt (JCPDS # No. 04-0802). It can be seen that the prepared catalyst materials all have two or more mixed crystal phases, further proving the heterogeneous phase characteristics of the catalyst materials.

[0080] Test Example 2 This test case is used to evaluate the electrochemical performance of the catalyst in the formic acid oxidation reaction (FAOR).

[0081] 1. Preparation of catalyst ink and working electrode The catalyst powder was dispersed in a mixture of isopropanol and 5% Nafion solution at a volume ratio of 1:0.005, and ultrasonicated for 25 min to obtain the catalyst ink. The platinum (Pt) content in the ink was accurately determined using inductively coupled plasma optical emission spectrometry (ICP-OES), and its concentration was uniformly adjusted to 0.54 mg. Pt ·mL -1 .

[0082] Subsequently, the catalyst ink was dropped onto the surface of a glassy carbon electrode (GCE, 5 mm in diameter) and allowed to dry naturally at room temperature to form a film, thus obtaining a catalyst-modified glassy carbon electrode. Based on this, the platinum loading on the glassy carbon electrode was calculated to be controlled at 16.5 μg·cm³. -2 .

[0083] 2. Electrochemical testing system All electrochemical tests were performed on a CHI 660E electrochemical workstation at 25 °C using the following three-electrode system.

[0084] Working electrode: Catalyst-modified glassy carbon electrode prepared in item 1 Counter electrode: graphite rod Reference electrode: Leak-free saturated calomel electrode (SCE).

[0085] 3. Formic acid oxidation reaction (FAOR) activity assessment The catalytic activity of FAOR was evaluated by cyclic voltammetry (CV). Tests were performed separately in solvent I and solvent II under nitrogen protection at a scan rate of 50 mV·s. -1 The potential scan range is 0.05 V to 1.2 V (vs RHE).

[0086] Solvent I: 0.5 mol / L H2SO4 solution, with deionized water as the solvent.

[0087] Solvent II: A mixed solution of 0.5 mol / L H2SO4 and 0.5 mol / L HCOOH, with deionized water as the solvent.

[0088] To eliminate the influence of solution impedance on kinetics, all recorded current data were compensated for 90% iR using the positive feedback function of the electrochemical workstation.

[0089] Ultimately, the current of FAOR was normalized to the mass activity (A mg). Pt - ¹), which is the current value divided by the platinum load mass on the electrode.

[0090] 4. Reaction pathway analysis and stability testing To distinguish between the two pathways of formic acid oxidation (direct and indirect pathways) and to assess the stability of the catalyst, chronoamperometry (CA) tests were performed.

[0091] Direct Reaction Pathway (DRP): This is carried out at a potential of 0.3 V (vs RHE). Here, formic acid is mainly oxidized to CO2 via a direct electron transfer pathway, avoiding the generation of a large amount of CO adsorbed toxins.

[0092] Indirect reaction pathway (IDRP): This is carried out at a potential of 0.9 V (vs RHE), at which formic acid readily generates CO adsorbent species through a dehydration step, and is then oxidized to CO2.

[0093] Both tests lasted 2000 s, and the electrolyte was 0.5 mol / L H2SO4 + 0.5 mol / L HCOOH (solvent II).

[0094] 5. Calculation of Key Performance Indicators Mass activity: Calculated based on the highest oxidation peak current value from the forward scan of the FAOR cyclic voltammetry curve and the platinum loading on the electrode. This indicator directly reflects the intrinsic catalytic activity of the catalyst per unit mass.

[0095] Direct path selectivity: evaluated by comparing the steady-state currents under two different paths. The specific calculation formula is: S DRP =I DRP / (I DRP + I IDRP ). Among them, I DRP I is the current value measured at 0.3V for 600 seconds. IDRP The current value was measured at 0.9 V for 600 seconds. A higher ratio indicates that the catalyst is more inclined to oxidize formic acid via the direct pathway and has stronger resistance to CO poisoning.

[0096] Residual current after 600s: The current value (I) was directly taken from the chronocurrent test conducted at 0.3V at the 600th second. 600 The ratio of this current to the initial current (I0) (I...) 600 The residual current (I0) is used to quantitatively evaluate the stability and poisoning resistance of a catalyst; a higher residual current indicates better catalyst durability.

[0097] 6. Assessment of resistance to CO toxicity First, the test was performed using cyclic voltammetry (CV) in a 0.5 mol / L H₂SO₄ solution (solvent I) at a scan rate of 0.05 V·s. - ¹; then the electrode was transferred to a mixed solution of 0.5 mol / L H₂SO₄ + 0.5 mol / L HCOOH (solvent II) until stable catalytic activity was obtained; subsequently, the electrode was transferred to a carbon monoxide-saturated electrolyte (a mixed solution of 0.5 mol / L H₂SO₄ + 0.5 mol / L HCOOH), and cyclic voltammetry was used again until stable FAOR activity was regained. By comparing the initial (I) initial ) and subsequent FAOR activity (I CO ), with [(I initial -I CO ) / I initial The catalyst's resistance to CO poisoning can be obtained by calculating the current decay (%) after CO is introduced by multiplying by 100%.

[0098] 7. Results Explanation The test results of the catalyst's mass activity, direct path selectivity, and residual current after 600 s are shown in Table 2.

[0099] Table 2

[0100] Note: The test results were obtained in a mixed electrolyte system of sulfuric acid and formic acid (solvent II); "Enhancement factor" refers to the ratio of the mass activity of the catalysts prepared in the examples and comparative examples to the mass activity of commercial platinum-carbon catalysts.

[0101] As shown in Table 2, the mass activity of catalysts Cat-1 to Cat-15 ranges from 0.7 to 4.9 A mg. Pt -1 Among them, Cat-5 (Pt 66.8 Te 33.1 Bi 0.1 The catalytic activity and direct pathway selectivity (69.6%) of / VXC-72R C were the best, and its mass activity was 32.7 times that of commercial platinum-carbon; while Cat-9 (Pt 64.6 Te 33.5 Bi 1.9 / C) showed the highest residual current (42.0%) after a 600 s stability test, indicating that it has the best catalytic stability among the listed catalysts.

[0102] Figure 3 The cyclic voltammetry (CV) plots are shown for catalysts Cat-1 to Cat-15 and commercial platinum-carbon catalysts. The CV plots show that, compared to the commercial platinum-carbon catalysts, the catalysts prepared in Examples 1-15 did not exhibit significant hydrogen adsorption / desorption peaks. Furthermore, compared to the untreated catalysts (Cat-1 to Cat-3), the acid-treated catalysts (Cat-4 to Cat-15) showed a more pronounced tellurium oxide peak in the CV plots (this characteristic peak appears in the range of +0.75 V to +0.80 V vs. SCE).

[0103] Figure 4 This is a comparison of the FAOR performance of the catalysts before and after acid treatment and the commercial platinum-carbon catalysts in Examples 1-6.

[0104] Figure 4 As can be seen from A to C, all catalysts (Cat-1 to Cat-6) have higher direct path current values ​​and selectivity in FAOR than commercial platinum-carbon catalysts. Compared with the catalysts before acid treatment (Cat-1 to Cat-3), the direct path current values ​​and selectivity of the catalysts after acid treatment (Cat-4 to Cat-6) are improved, and Cat-5 has the highest direct path current value and selectivity.

[0105] Figure 4Figures D to E show the current-time curves of each catalyst to evaluate their stability in FAOR. As can be seen from the figure, the current values ​​of Cat-2, Cat-4, Cat-5, and Cat-6 still exceed those of commercial platinum-carbon catalysts after 600 s.

[0106] Figure 4 As can be seen from F, after a 600-second stability test, Cat-4 had the highest residual current value among Cat-1 to Cat-6, indicating that it had the best stability.

[0107] Figure 4 G and H are CV diagrams obtained by testing different catalysts before and after CO introduction. The diagrams show that the direct path current values ​​of each catalyst decrease to varying degrees after CO introduction.

[0108] Figure 4 As can be seen from I, the direct path current value attenuation is least in Cat-1 (Pt) after CO is introduced. 41.9 Te 42.5 Bi 15.6 / VXC-72R C), indicating that it has the best resistance to poisoning. Compared to Cat-4 (Pt 55.9 Te 43.3 Bi 0.8 / VXC-72R C) and Cat-5 (Pt 66.8 Te 33.1 Bi 0.1 / VXC-72R C), Cat-1 exhibits better resistance to poisoning, which may be due to the fact that more tellurium and bismuth elements can act as functional anti-poisoning components, effectively inhibiting CO adsorption and thus significantly improving the catalyst's resistance to poisoning.

[0109] Figure 5 This is a comparison of the catalytic performance of catalysts supported on different carbon supports (Cat-7 to Cat-15) and commercial platinum-carbon catalysts in FAOR in Examples 7-15.

[0110] Figure 5 As can be seen from A to C, the direct path current values ​​of each catalyst in FAOR are higher than those of commercial platinum-carbon catalysts, and Cat-8 has the highest direct path current value.

[0111] Figure 5 The D~F diagram shows the current-time curves of Cat-7 to Cat-15 to evaluate their stability in FAOR. It can be clearly observed that the current values ​​of Cat-7 to Cat-15 still exceed those of commercial platinum-carbon catalysts after 600 s.

[0112] Test Example 3: Membrane Electrode Assembly Testing 1. Fabrication of membrane electrode assembly The membrane electrode assembly (MEA) was fabricated using a hot-pressing method. First, the catalyst and a 5% Nafion solution were co-dispersed in a water / isopropanol mixed solvent (volume ratio 1:4), and the mixture was ultrasonically treated for 1 h to form a uniform catalyst ink. Subsequently, the ink was uniformly coated onto the Nafion 212 membrane using an ultrasonic sprayer at a temperature of 50 °C.

[0113] Based on the different anode catalysts, the following two types of membrane electrodes were prepared.

[0114] Membrane electrode I: The catalyst Cat-5 from Example 5 was used as the anode catalyst, and its platinum loading was controlled at 0.52 mg. Pt ·cm -2 ; Membrane Electrode II: 70% commercial platinum-carbon catalyst was used as the anode catalyst, with the platinum loading controlled at 0.50 mg. Pt ·cm -2 .

[0115] Both membrane electrode assemblies used a 70% commercial platinum-carbon catalyst as their cathodes, with a platinum loading of 2.0 mg. Pt ·cm -2 .

[0116] Finally, the anode gas diffusion layer, cathode gas diffusion layer, Nafion 212 membrane with catalyst loaded on both sides, and gasket were hot-pressed at 130 °C and 7 MPa for 120 s to complete the MEA encapsulation, resulting in an active area of ​​1 × 1 cm². 2 .

[0117] 2. Evaluation of membrane electrode catalytic performance The MEA was installed between two graphite flow field plates in a single-cell test fixture and tested using the XQ-1000 fuel cell test system provided by the Fujian Energy Materials Science and Technology Innovation Laboratory, China, under operating conditions of 80 ℃ and 100% relative humidity. High-purity oxygen was introduced as the oxidant at the cathode at a flow rate of 500 sccm and an oxygen pressure of 100 kPa (absolute pressure). A 9 mol / L formic acid solution (deionized water as solvent) was introduced as the reactant at a flow rate of 5 mL / min.

[0118] Test results are as follows Figure 6 As shown.

[0119] Figure 6 As can be seen from A to B, the peak power density of Cat-5 reaches 229.0 W·g. Pt -1 The peak power density of commercial platinum-carbon catalysts is 139.7 W·g. Pt -1The peak power density of Cat-5 is 1.6 times that of commercial platinum-carbon catalysts, indicating that the Cat-5 sample has excellent membrane electrode catalytic performance.

[0120] In summary, the one-dimensional heterogeneous platinum-based catalysts with different supports prepared in this invention exhibit excellent anodic catalytic performance in direct formic acid fuel cells. Among them, the untreated platinum tellurium bismuth catalyst shows excellent resistance to CO poisoning, while the acid-treated bismuth-doped platinum tellurium catalyst, while maintaining good resistance to CO poisoning, also shows significantly improved catalytic activity, stability, and selectivity for the direct formic acid oxidation pathway.

[0121] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A method for preparing a one-dimensional platinum-based catalyst, characterized in that, This one-dimensional platinum-based catalyst has a nanorod structure and is a platinum tellurium bismuth catalyst or a bismuth-doped platinum tellurium catalyst. The preparation method includes: (1) In the presence of a dispersant, platinum precursor, tellurium precursor, bismuth precursor and ascorbic acid are subjected to a hydrothermal reaction in an aqueous solvent to form a platinum-tellurium-bismuth ternary heterostructure alloy; (2) The platinum-tellurium-bismuth ternary heterostructure alloy is loaded onto a carbon material to obtain a platinum-tellurium-bismuth catalyst; Optionally, the preparation method further includes: (3) The platinum tellurium bismuth catalyst obtained in step (2) is subjected to acid treatment to de-alloy, and bismuth-doped platinum tellurium catalyst is obtained.

2. The preparation method according to claim 1, characterized in that, In step (1), the platinum precursor is tetraammineplatinum nitrate, the tellurium precursor is potassium tellurite and / or sodium tellurite, and the bismuth precursor is bismuth oxycarbonate. Preferably, the amounts of the platinum precursor, tellurium precursor, and bismuth precursor are 1:(0.8~1.2):(0.3~1.5) based on the molar ratio of platinum, tellurium, and bismuth.

3. The preparation method according to claim 1 or 2, characterized in that, In step (1), the dispersant is polyvinylpyrrolidone; Preferably, the concentration of polyvinylpyrrolidone in the aqueous solvent is 15-30 mg / mL; Preferably, the concentration of ascorbic acid in the aqueous solvent is 5-20 mg / mL; Preferably, the aqueous solvent is composed of water and alcohol in a volume ratio of 1:(0.5~2.5); More preferably, the alcohol is ethylene glycol.

4. The preparation method according to any one of claims 1-3, characterized in that, In step (1), the temperature of the hydrothermal reaction is 160~210℃. o C, the reaction time is 3~12 h; Preferably, the operation process of step (1) includes: (1-1) The platinum precursor, tellurium precursor, bismuth precursor, ascorbic acid and dispersant are added to the aqueous solvent and ultrasonically dispersed at 25~40 kHz for 0.5~3 h to obtain a mixture; (1-2) The mixture is transferred to a high-pressure reactor for hydrothermal reaction. The resulting product is subjected to solid-liquid separation and first washing to obtain a platinum-tellurium-bismuth ternary heterostructure alloy. More preferably, the solvent used for the first washing is a mixture of ethanol and acetone, and the volume ratio of ethanol to acetone is 1:(4~10).

5. The preparation method according to any one of claims 1-4, characterized in that, In step (2), the carbon material is selected from at least one of Vulcan XC-72R carbon powder, Ketjen black, ordered mesoporous carbon, and nitrogen-doped mesoporous carbon; Preferably, the mass ratio of the platinum-tellurium-bismuth ternary heterostructure alloy to the carbon material is (1~2):1; Preferably, the loading is performed under ultrasonic conditions, with an ultrasonic frequency of 25~40 kHz and an ultrasonic time of 1~5 h.

6. The preparation method according to any one of claims 1-5, characterized in that, The operation process of step (2) includes: (2-1) The platinum-tellurium-bismuth ternary heterostructure alloy and the carbon material are added to an alcohol solvent and ultrasonically dispersed. (2-2) The product obtained in step (2-1) is subjected to solid-liquid separation to obtain the platinum tellurium bismuth catalyst.

7. The preparation method according to any one of claims 1-6, characterized in that, In step (3), the acid used for acid treatment is nitric acid with a concentration of 4~8 mol / L, the acid treatment temperature is 50~70 ℃, and the time is 10~60 min; Preferably, the operation process of step (3) includes: (3-1) The platinum tellurium bismuth catalyst is added to nitric acid, and the acid treatment is carried out under stirring conditions; (3-2) The product obtained in step (3-1) is subjected to solid-liquid separation and a third washing; Preferably, the solvent used in the third washing is ethanol.

8. A one-dimensional platinum-based catalyst prepared by the preparation method according to any one of claims 1-7.

9. The one-dimensional platinum-based catalyst according to claim 8, characterized in that, The platinum-based catalyst is a platinum-tellurium-bismuth catalyst, with the atomic percentage of platinum (30%–45%), tellurium (30%–45%), and bismuth (12%–38%) as the total atomic percentage of platinum, tellurium, and bismuth; or The platinum-based catalyst is a bismuth-doped platinum-tellurium catalyst, with the atomic percentage of platinum being 50% to 74%, tellurium 25% to 47%, and bismuth 0.05% to 3%, based on the total atomic percentage of platinum, tellurium, and bismuth.

10. The use of the one-dimensional platinum-based catalyst according to claim 8 or 9 in the formic acid oxidation reaction or in the preparation of a direct formic acid fuel cell; Preferably, its application in the preparation of direct formic acid fuel cells includes: The one-dimensional platinum-based catalyst was used to prepare the membrane electrode assembly for a direct formic acid fuel cell.

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