Pt-based molecular sieve template carbon catalyst, and preparation method and application thereof

Abstract

This invention provides a Pt-based molecular sieve templated carbon catalyst, its preparation method, and its application. The catalyst comprises zeolite templated carbon with a three-dimensional porous structure, wherein the pores of the zeolite templated carbon contain Pt nanoparticles and La. 3+ Ions; Pt nanoparticles are confined within the pores. The zeolite template carbon of this invention possesses a uniform pore structure and the three-dimensional continuous porous characteristics of a molecular sieve, replicating the characteristic pore size of a Y molecular sieve. The preparation method of this invention involves modifying the molecular sieve template with La ion exchange, followed by CVD reaction, selective reduction, and alkaline etching, precisely replicating the characteristic pore size of a Y molecular sieve without LaF3 precipitation or significant carbon deposition. This invention also provides the application of the above-mentioned Pt-based molecular sieve template carbon catalyst in catalytically improving the kinetics of the cathode oxygen reduction reaction. It can be combined with S-1 molecular sieves to construct highly efficient oxygen transport channels, showing great application potential in fuel cells and metal-air batteries.

Description

Technical Field

[0001] This invention belongs to the field of carbon materials technology, specifically relating to a Pt-based molecular sieve template carbon catalyst, its preparation method, and its application. Background Technology

[0002] With the urgent global demand for renewable energy, clean and sustainable proton exchange membrane fuel cells (PEMFCs) and high-theoretical-energy-density metal-air batteries are considered promising energy conversion devices. The oxygen reduction reaction (ORR) is a key electrode reaction in fuel cells and metal-air batteries; however, it is a kinetically slow heterogeneous catalytic process requiring four electron transfer processes, significantly hindering battery performance improvement. The rational design and synthesis of advanced electrocatalysts with good catalytic performance is an effective way to improve the ORR rate at the cathode and overcome the sluggish cathode kinetics of fuel cells. Pt-based catalysts have become a research hotspot due to their excellent ORR activity. According to industry regulations on platinum (Pt) loading in PEMFCs, the total Pt loading must be less than 0.125 mg·cm³. 2 Therefore, how to reduce the Pt load without damaging or improving cathode performance has become a major focus of research in electrocatalysis for fuel cell systems. Summary of the Invention

[0003] To overcome the problems existing in the prior art, one objective of this invention is to provide a Pt-based molecular sieve template carbon catalyst. A second objective of this invention is to provide a method for preparing the aforementioned Pt-based molecular sieve template carbon catalyst. A third objective of this invention is to provide applications of the aforementioned Pt-based molecular sieve template carbon catalyst. A fourth objective of this invention is to provide a battery assembly. A fifth objective of this invention is to provide a battery.

[0004] The size of nanomaterials often plays a crucial role in controlling the physical and chemical properties of catalytic applications. When particle size is reduced to the nanoscale, quantum size effects occur, altering the surface energy of the material due to the non-co-coordination and energy level changes of the d orbitals of metal atoms, thereby enabling the spatial positioning of electrons. In ORR electrocatalysis, H₂O (4e⁻) The formation ratio of the products of the process is strongly dependent on the number of atoms in the Pt clusters, requiring more than 14 atoms. Therefore, platinum nanoclusters have proven to be highly efficient ORR electrocatalysts in fuel cell systems. Another method for synthesizing platinum nanoclusters (PtNCs) is to encapsulate them in nanoscale pores, for example, using microporous (diameter less than 2 nm) carbon materials. Among microporous carbon materials, zeolite-templated carbon (ZTC) is a novel hard carbon material that replicates the structure of molecular sieves, and its ordered microporous structure has made it a popular choice for supporting platinum clusters. ZTC has great potential as a catalyst support because of its large specific surface area and the high electrical conductivity resulting from its three-dimensional (3D) interconnected pore structure composed of graphene-like carbon frameworks. Typically, ZTC is synthesized using small molecules, such as ethylene, as a carbon source, which is then deposited into the pores of a molecular sieve through high-temperature pyrolysis to replicate the pores. However, the carbonization of these small hydrocarbons usually requires high-temperature reactions to fix the carbon source within the pores. At such high temperatures, reactions often occur non-selectively on both the outer surface and the inner pore walls. This typically leads to coke deposition on the outer surface, severely restricting diffusion into the pores and preventing effective confinement of Pt particles, thus affecting catalytic performance. Furthermore, large-scale conversion of small molecules such as oxygen relies on water as a source of protons and electrons. However, the extremely low solubility of oxygen in water significantly limits the achievable current density using liquid-phase electrocatalysis. These limitations become bottlenecks in improving ORR performance. Therefore, developing a pore-size-matched, non-precipitated, carbon-depositing, highly dispersed Pt-based ZTC catalyst and composite catalytic system is crucial for improving ORR performance. This invention innovatively modifies the molecular sieve template with rare earth element La ion exchange. 3+ Entering the pores of Y molecular sieves can reduce carbon deposition during chemical vapor deposition (CVD) and avoid pore blockage caused by uneven carbon deposition.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] The first aspect of this invention provides a Pt-based molecular sieve templated carbon catalyst, comprising zeolite templated carbon with a three-dimensional porous structure, wherein the pores of the nitrogen-doped zeolite templated carbon contain Pt nanoparticles and La. 3+ Ions; the Pt nanoparticles are confined within the pores.

[0007] Preferably, the particle size of the Pt-based molecular sieve template carbon catalyst is 150-600 nm.

[0008] Preferably, the Pt-based molecular sieve template carbon catalyst has a dominant pore size of 0.59 nm.

[0009] The second aspect of this invention provides a method for preparing the Pt-based molecular sieve template carbon catalyst described in the first aspect, comprising the following steps: S1. Add the alkali source, silicon source, aluminum source, platinum source and complexing agent to water, age the mixture first, and then carry out a hydrothermal reaction; collect the solid product after the reaction, calcine it to obtain a molecular sieve template. S2. Place the molecular sieve template of S1 in an aqueous solution containing lanthanum source for ion exchange to obtain a lanthanum-modified molecular sieve template. S3. The lanthanum-modified molecular sieve template of S2 is subjected to chemical vapor deposition (CVD) in a mixed atmosphere of nitrogen, water vapor and acetylene to obtain zeolite template carbon with replicated template pore size; then a reduction reaction is carried out in a mixed atmosphere of hydrogen and argon, and the reaction is followed by alkali treatment to obtain the Pt-based molecular sieve template carbon catalyst.

[0010] Preferably, the alkali source includes at least one of potassium hydroxide and sodium hydroxide.

[0011] Preferably, the aluminum source includes at least one of sodium aluminate, aluminum hydroxide, and aluminum nitrate.

[0012] Preferably, the silicon source includes at least one of tetraethyl silicate, sodium silicate, and colloidal titanium dioxide.

[0013] Preferably, the platinum source includes chloroplatinic acid or its hydrate.

[0014] Preferably, the complexing agent is ethylenediamine.

[0015] Preferably, in step S1, the aging step includes: standing at room temperature for 10-40 hours.

[0016] Preferably, in step S1, the reaction temperature of the hydrothermal reaction is 80-120℃.

[0017] Preferably, in step S1, the reaction time of the hydrothermal reaction is 10-15 h.

[0018] Preferably, in step S1, the calcination temperature is 300-400℃.

[0019] Preferably, in step S1, the roasting time is 1-4 hours.

[0020] Preferably, in step S1, the calcination is carried out in an air atmosphere.

[0021] Preferably, in step S1, the dominant pore size of the molecular sieve template is 0.5-0.7 nm.

[0022] Preferably, in step S2, the temperature of the ion exchange is 70-90°C.

[0023] Preferably, in step S2, the concentration of the lanthanum source in the aqueous solution containing the lanthanum source is 0.1-2 mol / L.

[0024] Preferably, in step S2, the lanthanum source is lanthanum nitrate or its hydrate.

[0025] Preferably, in step S2, the mass ratio of the molecular sieve template to the aqueous solution containing lanthanum source is 1:(30-100).

[0026] Preferably, in step S2, the ion exchange time is 6-12 h.

[0027] Preferably, in step S2, the ion exchange is performed 1-3 times.

[0028] Preferably, in step S3, the reaction temperature of the chemical vapor deposition reaction is 400-600℃.

[0029] More preferably, in step S3, the temperature is first raised to the reaction temperature of the chemical vapor deposition reaction under a nitrogen atmosphere.

[0030] Preferably, in step S3, the volume percentage of acetylene in the mixed atmosphere of nitrogen, water vapor and acetylene is 3%-10%.

[0031] More preferably, the volume percentage of acetylene is 4%-6%.

[0032] Preferably, in step S3, the volume percentage of water vapor in the mixed atmosphere of nitrogen, water vapor and acetylene is 2%-5%.

[0033] Preferably, in step S3, the reaction time of the chemical vapor deposition reaction is 3-6 hours.

[0034] Preferably, step S3 further includes the following steps: after the chemical vapor deposition reaction, the product is calcined in a nitrogen atmosphere and then reduced in a mixed atmosphere of hydrogen and argon.

[0035] More preferably, the calcination temperature is 800-1000℃.

[0036] More preferably, the calcination time is 1-3 h.

[0037] Preferably, in step S3, the reaction temperature of the reduction reaction is 250-350℃.

[0038] Preferably, in step S3, the reaction time of the reduction reaction is 1-3 h.

[0039] Preferably, in step S3, the alkaline treatment procedure includes: pre-treating the product after the reduction reaction in hydrochloric acid solution, separating the solid product and washing it; then placing it in sodium hydroxide solution for alkaline etching, separating the solid product and washing it; and then placing it back in hydrochloric acid solution for post-treatment, separating the solid product and washing it.

[0040] More preferably, the concentration of the hydrochloric acid solution used in the pretreatment is 0.1-0.5 mol / L.

[0041] More preferably, the pretreatment time is 1-4 hours.

[0042] More preferably, the concentration of the sodium hydroxide solution is 1-4 mol / L.

[0043] More preferably, the alkaline etching time is 1-4 hours.

[0044] More preferably, the concentration of the hydrochloric acid solution used in the post-treatment is 0.1-0.5 mol / L.

[0045] More preferably, the post-processing time is 1-4 hours.

[0046] The third aspect of this invention provides the Pt-based molecular sieve template carbon catalyst described in the first aspect for any of the following applications: a) Application in oxygen reduction reaction catalysts; b) Applications in battery manufacturing.

[0047] A fourth aspect of the present invention provides a battery assembly including a positive electrode, a negative electrode, and an electrolyte; the positive electrode material of the positive electrode includes the Pt-based molecular sieve template carbon catalyst described in the first aspect.

[0048] Preferably, the electrolyte comprises S-1 molecular sieve.

[0049] More preferably, the S-1 molecular sieve is synthesized via TPAOH template-guided synthesis.

[0050] More preferably, the S-1 molecular sieve has a dominant pore size of 0.59 nm.

[0051] More preferably, the electrolyte also includes perchloric acid and water.

[0052] A fifth aspect of the present invention provides a battery comprising the battery assembly described in the fourth aspect.

[0053] Preferably, the battery is a fuel cell.

[0054] More preferably, the fuel cell is a proton exchange membrane fuel cell (PEMFC).

[0055] Preferably, the battery is a metal-air battery.

[0056] The beneficial effects of this invention are: This invention provides a Pt-based molecular sieve templated carbon catalyst, using zeolite templated carbon with a three-dimensional porous structure as a support, the channels of which contain ion-exchange bonded La. 3+ The zero-valent Pt nanoclusters are confined within the pores of carbon materials. The zeolite template carbon of this invention possesses a uniform pore structure and the three-dimensional continuous porous characteristics of molecular sieves, replicating the 0.59 nm characteristic pore size of Y molecular sieves, and exhibits no LaF3 precipitation or significant carbon deposition.

[0057] This invention also provides a method for preparing the above-mentioned Pt-based molecular sieve template carbon catalyst, which has the following beneficial effects: (1) La ion exchange modification: La 3+ Entering the Y molecular sieve pores reduces carbon deposition during CVD, avoids pore blockage caused by uneven carbon deposition, and provides conditions for subsequent alkaline etching; (2) The “HCl pretreatment-NaOH etching-HCl posttreatment” process replaces the traditional acid washing, which can efficiently remove molecular sieve templates and impurities and avoid LaF3 precipitation caused by acid washing. The preparation method of this invention is controllable, the parameters of each step are clear, the alkaline etching process is mild, avoids the defects of traditional acid washing, the pore size replication accuracy is high, the repeatability is good, and it is suitable for large-scale production.

[0058] This invention also provides the application of the aforementioned Pt-based molecular sieve template carbon catalyst in cathode active materials, which can be used as a catalyst to improve the kinetics of the cathode oxygen reduction reaction (ORR). Furthermore, the precise matching of the Pt-based molecular sieve template carbon with a characteristic pore size of 0.59 nm to the S-1 pore size allows for the construction of highly efficient oxygen transport channels. The half-wave potential of the composite catalytic system reaches 0.852 V, superior to the 37 mV of commercial Pt / C; the limiting current density reaches 10.13 mA / cm². 2 It is 1.88 times higher than that of pure perchloric acid electrolyte; the Tafel slope is as low as 85.5 mV / dec, and the kinetic reaction rate is faster. Attached Figure Description

[0059] Figure 1 This is a scanning electron microscope (SEM) image of the PtO2@Y molecular sieve template. Figure 2 SEM image of La-Pt@YZTC-OH catalyst; Figure 3 Transmission electron microscopy (TEM) image of the La-Pt@YZTC-OH catalyst; Figure 4BET nitrogen adsorption / desorption curves of the catalyst of Example 1, the catalysts of Comparative Examples 1-2, PtO2@Y molecular sieve template and S-1 molecular sieve. Figure 5 Pore ​​size distribution diagrams of the catalyst in Example 1, the catalysts in Comparative Examples 1-2, the PtO2@Y molecular sieve template, and the S-1 molecular sieve; Figure 6 XRD patterns of the catalyst of Example 1, the catalysts of Comparative Examples 1-2, and the PtO2@Y molecular sieve template; Figure 7 LSV curves of the catalyst of Example 1, the catalysts of Comparative Examples 1-2, and the Pt / C catalyst in 0.1M perchloric acid electrolyte; Figure 8 The half-wave potential comparison diagrams of the catalyst of Example 1, the catalysts of Comparative Examples 1-2, and the Pt / C catalyst in 0.1M perchloric acid electrolyte are shown. Detailed Implementation

[0060] The present invention will be further described in detail below through specific embodiments. Unless otherwise specified, the raw materials used in the following embodiments can be obtained from conventional commercial channels or prepared and isolated through simple synthesis; unless otherwise specified, the processes employed are conventional processes in the art.

[0061] Example 1 This embodiment provides a Pt-based molecular sieve templated carbon catalyst, the preparation method of which is as follows: Synthesis of S1, PtO2@Y molecular sieve templates 2.53 g of NaOH was dissolved in 22.16 g of deionized water, and after ultrasonic dissolution, 0.6166 g of Al(OH)3 was added and stirred for 30 min until completely dissolved. 7.918 g of Ludox HS-30 was weighed and added dropwise to the above solution with stirring, and stirring was continued for 2 h. 2.587 g of 2.44 wt% chloroplatinic acid hexahydrate aqueous solution was mixed with 124 uL of EDA, shaken well, and then added dropwise to the synthesis solution. The mixture was stirred for 6 h and aged at room temperature for 24 h. The synthesis solution was transferred to a 50 mL polytetrafluoroethylene reactor and crystallized at 100 °C for 12 h. The product was washed three times by centrifugation with deionized water, dried overnight at 80 °C, ground, and calcined at 350 °C for 2 h in air at a rate of 0.7 °C / min to obtain the PtO2@Y template.

[0062] Figure 1 The image shows a SEM image of a PtO2@Y molecular sieve template, which has a regular octahedral structure. Figure 4 and Figure 5The figures show the BET nitrogen adsorption / desorption curves and pore size distribution, respectively. The dominant pore size of the PtO2@Y template is 0.59 nm.

[0063] S2, La 3+ Ion exchange modification The PtO2@Y template was placed in a 0.5 M lanthanum nitrate hexahydrate aqueous solution at 80℃ with a liquid-to-solid mass ratio of 50:1 and stirred for 8 h. The product was washed 5 times with deionized water and dried at 80℃ overnight. The above ion exchange process was repeated twice to obtain the La-exchanged PtO2@Y template.

[0064] Preparation of S3, La-Pt@YZTC-OH catalysts Weigh 0.3 g of La-exchanged PtO2@Y template and place it in a tube furnace. Under N2 atmosphere, heat to 500℃ at 5℃ / min (N2 flow rate 100 sccm); introduce a mixed gas of C2H2:N2:H2O=5%:92%:3% (total flow rate 100 sccm) and maintain for 4 h for CVD reaction; switch to N2 atmosphere (flow rate 100 sccm) and heat to 900℃ at 5℃ / min for 2 h; then switch to 5% H2 / Ar atmosphere (flow rate 100 sccm) and cool to 300℃ at 5℃ / min for 2 h for reduction.

[0065] After cooling to room temperature, the product was dissolved in 40 mL of 0.15 M HCl and stirred for 2 h, then centrifuged and washed. 2 M NaOH solution was added, and the mixture was stirred at 80 °C for 2 h, then centrifuged and washed. 0.15 M HCl was then added, and the mixture was stirred at room temperature for 2 h, centrifuged and washed 3 times, and dried at 100 °C for 12 h to obtain the Pt-based molecular sieve template carbon catalyst, denoted as La-Pt@YZTC-OH catalyst.

[0066] Figure 2 and Figure 3 The images are SEM and TEM images of the La-Pt@YZTC-OH catalyst, respectively. The uniform and abundant pore structure on its surface can be seen, which is a ZTC support that replicates the pore size of the template. The average particle size of the Pt nanoclusters is 4.89 nm. Figure 4 and Figure 5 The figures show the BET nitrogen adsorption / desorption curves and pore size distribution, respectively. The dominant pore size of the La-Pt@YZTC-OH catalyst is 0.59 nm.

[0067] Comparative Example 1 This comparative example provides a Pt-based molecular sieve templated carbon catalyst, the preparation method of which is the same as in Example 1, except that step S3 of the preparation of the comparative catalyst La-Pt@YZTC-HF does not use alkaline etching. The specific steps are as follows: Following the steps in Example 1, CVD deposition and reduction were performed. After cooling, the product was dissolved in a mixture of 40 mL of 0.3 M HF and 0.15 M HCl, stirred for 2 h, etched twice, centrifuged and washed three times, and dried at 100 °C for 12 h to obtain the La-Pt@YZTC-HF catalyst.

[0068] Figure 6 The XRD patterns of the catalyst of Example 1, the catalysts of Comparative Examples 1-2, and the PtO2@Y molecular sieve template are shown. The XRD pattern of the catalyst of Comparative Example 1 shows LaF3 characteristic peaks at 24.79° and 27.65°, while the catalyst of Example 1 does not have LaF3 characteristic peaks, indicating that there is no LaF3 precipitation.

[0069] Comparative Example 2 This comparative example provides a Pt-based molecular sieve templated carbon catalyst, the preparation method of which is the same as in Example 1, except that: the comparative catalyst Pt@YZTC-OH is prepared by using untreated La 3+ The exchanged PtO2@Y catalyst was subjected to CVD deposition, reduction and etching according to the steps of Example 1 to obtain the Pt@YZTC-OH catalyst.

[0070] Figure 6 The XRD pattern of Pt@YZTC-OH shows a strong Pt characteristic peak.

[0071] Characterization of catalytic performance of oxygen reduction reaction (ORR) 1. Synthesis of S-1 molecular sieve 39.17 mL of 22.3 wt% TPAOH aqueous solution, 44.52 mL of deionized water, and 26.31 mL of TEOS were mixed and stirred at 500 rpm for 23 h. The homogenized solution was then transferred to a 100 mL reactor and crystallized at 170 °C for 29 h. After cooling, the product was collected, washed five times with deionized water (centrifuged at 7830 rpm for 10 min), dried at 70 °C, ground, and placed in a tube furnace. The temperature was increased to 550 °C in air for 3 h, held for 10 h, and then cooled to obtain S-1 molecular sieve with a dominant pore size of 0.59 nm (see...). Figure 5 ), with a surface contact angle of 18°.

[0072] 2. Preparation of S-1 microporous water electrolyte Weigh out 10 mg, 20 mg, 30 mg, and 40 mg of S-1 molecular sieve, respectively, add 100 mL of deionized water to each, sonicate for 1 h, and stir at room temperature for 24 h; centrifuge at 1500 rpm for 15 min, collect the supernatant, and repeat centrifugation 3 times for purification; redisperse the purified S-1 in 100 mL of deionized water, sonicate for 1 h, and stir for 6 h; add 0.1 M perchloric acid, sonicate for 0.5 h, and obtain S-1 microporous water electrolytes of different concentrations.

[0073] 3. Preparation of catalyst dispersion and [other components] Preparation of catalyst dispersion (hereinafter referred to as slurry): Take 2 mg of catalyst powder and place it in 150 μL of anhydrous ethanol, then add 40 μL of deionized water and 20 μL of Nafion solution and mix well. Sonicate the mixture for more than 30 minutes until the slurry becomes viscous, and keep the water temperature of the sonicator below 40℃ during the process.

[0074] Preparation of commercial Pt / C slurry: Place 5 mg of 20 wt% commercial Pt / C catalyst powder in 600 μL of isopropanol, then add 350 μL of deionized water and 50 μL of Nafion solution and mix well. Sonicate the mixture for at least 30 min until the slurry becomes viscous, keeping the ultrasonic water temperature below 40°C during this process.

[0075] After preparing the slurry, it is coated onto a glassy carbon electrode to obtain a glassy carbon electrode with a catalyst supported.

[0076] 4. ORR Catalytic Performance Test (1) Test conditions A three-electrode system was used, with the working electrode being a glassy carbon electrode supported on La-Pt@YZTC-OH catalyst (catalyst loading of 0.022 mg / cm²), the reference electrode being a saturated calomel electrode (SCE), and the counter electrode being a carbon rod. The electrolytes were pure 0.1 M perchloric acid and the S-1 microporous water electrolyte prepared above. The test conditions were: room temperature and scan rate of 5 mV / s.

[0077] (2) Test results Figure 7 LSV curves of the catalyst of Example 1, the catalysts of Comparative Examples 1-2, and the Pt / C catalyst in 0.1M perchloric acid electrolyte; Figure 8 The graph shows a comparison of the half-wave potentials of the catalyst in Example 1, the catalysts in Comparative Examples 1-2, and the Pt / C catalyst in 0.1 M perchloric acid electrolyte. In pure 0.1 M perchloric acid electrolyte, the Pt@YZTC-OH catalyst achieved a half-wave potential of 0.852 V, which is superior to 30 mV for commercial Pt / C, and its kinetic density at 0.9 V was 1.69 mA / cm². 2 This is higher than the 1.25 mA / cm² of commercial Pt / C. 2 Furthermore, its Pt loading is only 2.53 wt%. The Tafel slope is 85.5 mV / dec, and the limiting current density is 5.41 mA / cm². 2 ; As the concentration of microporous water increases, the limiting current also increases accordingly. In a 40 mg / mL S-1 microporous water electrolyte, the limiting current density of the catalyst is 10.13 mA / cm², which is superior to commercial Pt / C and comparative catalysts. Its limiting current density is 2.3 times higher than that in pure 0.1 M perchloric acid electrolyte, greatly enhancing the ORR catalytic activity.

[0078] The La-Pt@YZTC-HF catalyst (Comparative Example 1) was tested in 0.1 M pure perchloric acid electrolyte, and the half-wave potential was 0.713 V, significantly lower than that of the catalyst in Example 1. The Pt@YZTC-HF catalyst without La ion exchange had a half-wave potential of 0.741 V and exhibited significant carbon deposition. In a 40 mg / mL microporous water electrolyte, the limiting current densities of commercial Pt / C, La-Pt@YZTC-HF, and Pt@YZTC-HF were 6.98, 7.48, and 7 mA / cm², respectively. 2 This is significantly lower than the catalyst of this invention. The kinetic densities of Pt / C, La-Pt@YZTC-HF, and Pt@YZTC-HF at 0.9 V are 1.25, 0.18, and 0.39 mA / cm², respectively. 2 The values ​​are all lower than those of the catalyst in Example 1.

[0079] In summary, this invention constructs a "microporous water" electrolyte using a Pt-based molecular sieve template carbon (ZTC) catalyst paired with an S-1 molecular sieve with a pore size close to 0.59 nm. The unique structure of the S-1, with its superhydrophilic surface and hydrophobic interior, enhances the oxygen content of the electrolyte, and the pore size matching between the catalyst and S-1 further optimizes oxygen transport efficiency. The composite catalytic system of this invention exhibits an ORR half-wave potential as high as 0.852 V (superior to 37 mV for commercial Pt / C) and a limiting current density of 10.13 mA / cm², significantly higher than the limiting current density in ordinary electrolytes, demonstrating enormous application potential in fuel cells and metal-air batteries.

[0080] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A Pt-based molecular sieve templated carbon catalyst, characterized in that, This includes zeolite-templated carbon with a three-dimensional porous structure, wherein the pores of the zeolite-templated carbon contain Pt nanoparticles and La. 3+ Ions; the Pt nanoparticles are confined within the pores.

2. The method for preparing the Pt-based molecular sieve template carbon catalyst according to claim 1, characterized in that, Includes the following steps: S1. Add the alkali source, silicon source, aluminum source, platinum source and complexing agent to water, age the mixture first, and then carry out a hydrothermal reaction; collect the solid product after the reaction, calcine it to obtain a molecular sieve template. S2. Place the molecular sieve template of S1 in an aqueous solution containing lanthanum source for ion exchange to obtain a lanthanum-modified molecular sieve template. S3. The lanthanum-modified molecular sieve template of S2 is subjected to chemical vapor deposition reaction in a mixed atmosphere of nitrogen, water vapor and acetylene to obtain zeolite template carbon with replicated template pore size; then a reduction reaction is carried out in a mixed atmosphere of hydrogen and argon, and the reaction is followed by alkali treatment to obtain the Pt-based molecular sieve template carbon catalyst.

3. The method for preparing the Pt-based molecular sieve template carbon catalyst according to claim 2, characterized in that, In step S1, the reaction temperature of the hydrothermal reaction is 80-120℃; And / or, the calcination temperature is 300-400℃.

4. The method for preparing the Pt-based molecular sieve template carbon catalyst according to claim 2, characterized in that, In step S2, the temperature of the ion exchange is 70-90℃.

5. The method for preparing the Pt-based molecular sieve template carbon catalyst according to claim 2, characterized in that, In step S3, the reaction temperature of the chemical vapor deposition reaction is 400-600℃; And / or, the reaction temperature of the reduction reaction is 250-350℃.

6. The method for preparing the Pt-based molecular sieve template carbon catalyst according to claim 2, characterized in that, In step S3, the alkaline treatment procedure includes: pre-treating the product after the reduction reaction in hydrochloric acid solution, separating the solid product and washing it; then placing it in sodium hydroxide solution for alkaline etching, separating the solid product and washing it; and then placing it back in hydrochloric acid solution for post-treatment, separating the solid product and washing it.

7. The Pt-based molecular sieve templated carbon catalyst of claim 1 is used in any of the following applications: a) Application in oxygen reduction reaction catalysts; b) Applications in battery manufacturing.

8. A battery assembly, characterized in that, It includes a positive electrode, a negative electrode, and an electrolyte; the positive electrode material of the positive electrode includes the Pt-based molecular sieve template carbon catalyst as described in claim 1.

9. The battery assembly according to claim 8, characterized in that, The electrolyte comprises S-1 molecular sieve.

10. A battery, characterized in that, Includes the battery assembly as described in claim 8 or 9.

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