A method for rapidly preparing a nano-particle platinum electrocatalyst by thermal shock
The rapid preparation of nanoparticle platinum electrocatalysts via thermal shock method solves the problems of complex processes and high energy consumption in existing technologies, and realizes an efficient and stable process for hydrogen production through water electrolysis.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HARBIN INST OF TECH
- Filing Date
- 2023-05-17
- Publication Date
- 2026-07-24
AI Technical Summary
Existing nanoparticle platinum electrocatalysts have complex synthesis processes and long production cycles, and their industrial applications involve high energy consumption and poor stability in water electrolysis for hydrogen production.
A rapid preparation of nanoparticle platinum electrocatalysts was achieved using a thermal shock method. This method involves pretreating a conductive substrate, loading a platinum source, and rapidly heating it to prepare nanoparticle platinum electrocatalysts. This process introduces a large number of dislocations and heterojunction interfaces, thereby increasing the number of active sites.
The preparation process is simplified, the cost is reduced, the activity and stability of the catalyst are improved, energy consumption is significantly reduced, the performance is superior to commercial carbon-platinum catalysts, and the stability is good for continuous use.
Smart Images
Figure CN116555808B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of electrochemical catalysts. Background Technology
[0002] Among numerous non-fossil energy sources, hydrogen energy stands out for its pollution-free nature and high energy density, making it a promising energy carrier. Reliable hydrogen production will likely make it a mainstream energy form in the future. Electrocatalytic water splitting is the primary method for hydrogen production, attracting significant attention in hopes of achieving efficient hydrogen production and reducing costs. The water electrolysis process involves an oxygen evolution reaction (OER) and a hydrogen evolution reaction (HER). The HER process is a reduction process that gains electrons, where hydrogen in the water gains electrons and is converted into hydrogen gas.
[0003] The key to this technology lies in preparing suitable catalysts to reduce the overpotential of water electrolysis, thereby reducing energy consumption and lowering costs. Currently, industrially applied water electrolysis catalysts are mainly pure noble metal electrocatalysts, including Ir / Ru-based oxides and Pt. Although they have excellent performance, their high cost and scarce reserves greatly limit their application, making it difficult to meet the requirements of industrial production and commercialization.
[0004] Currently, there are many similar methods for preparing platinum nanoparticle catalytic electrode materials. However, these methods have certain drawbacks, such as complicated preparation processes and long production cycles. Moreover, the prepared catalysts have a low number of active centers on the surface and low efficiency, requiring high potentials to achieve sufficient overpotential to promote catalytic reactions and electrolyze water molecules. Furthermore, some existing catalysts are prone to deactivation during long-term operation, affecting the stability and lifespan of the catalysts. This leads to an increase in overpotential in the later stages of the catalyst cycle, increased energy consumption, and increased maintenance and replacement costs for the entire hydrogen production system. Summary of the Invention
[0005] This invention aims to address the problems of complex synthesis processes and long production cycles of existing nanoparticle platinum electrocatalytic electrode materials, as well as the high energy consumption and poor stability of existing industrial catalysts for hydrogen production through water electrolysis. Therefore, it provides a method for rapidly preparing nanoparticle platinum electrocatalysts using a thermal shock method.
[0006] A method for rapidly preparing nanoparticle platinum electrocatalysts via thermal shock is provided, comprising the following steps:
[0007] I. Pretreatment of the conductive substrate:
[0008] The conductive substrate is immersed in nitric acid and then heat-treated to obtain the pretreated substrate.
[0009] II. Loading the platinum source onto the substrate:
[0010] The platinum source was dissolved in ethanol to obtain a platinum source solution. The platinum source solution was then dropped onto the pretreated substrate and allowed to stand and dry to obtain a substrate loaded with the platinum source.
[0011] III. Rapid heating:
[0012] The two ends of the substrate loaded with the platinum source were clamped to the positive and negative terminals of a DC power supply, respectively. Under the condition of a current of 2A to 70A, the power was applied for 0.5s to 10s. Finally, the power was turned off and the sample was taken out to obtain the nanoparticle platinum electrocatalyst loaded on the substrate.
[0013] The beneficial effects of this invention are:
[0014] 1. This invention proposes a method for the rapid preparation of nanoparticle platinum electrocatalysts via thermal shock. Nanoparticle platinum is uniformly loaded onto a substrate, eliminating the need for other reducing agents. This ensures the stability of the catalytic material while maintaining a low platinum loading, thus reducing costs.
[0015] 2. This preparation method is simple to operate, highly flexible, and significantly shortens the production cycle, which is conducive to large-scale industrial production. Compared with other production processes that take several to more than ten hours to prepare, the required heating time is only 0.5 to 10 seconds, which helps to reduce equipment occupancy time and significantly improve industrial production efficiency.
[0016] 3. This invention prepares a nanoparticle platinum electrocatalyst, introducing a large number of dislocations and heterojunction interfaces, which increases the number of active sites and thus enhances the catalyst's activity. Using the prepared platinum catalyst as the working electrode and a 1 mol / L KOH solution as the electrolyte in a three-electrode testing system, the HER reaction reached 10 mA / cm². 2 At a current density of only 19mV, the overpotential is greatly reduced, significantly improving energy consumption. Its performance is far superior to that of commercial carbon platinum, and its overpotential decay is negligible even after 24 hours, demonstrating remarkable catalytic stability.
[0017] Instruction manual illustrations
[0018] Figure 1 This is a schematic diagram of the method for rapid preparation of nanoparticle platinum electrocatalysts by thermal shock according to the present invention. 1 and 2 are power connectors, 3 is the substrate supporting the platinum source, and 4 is the fixture.
[0019] Figure 2 Scanning electron microscope image of the platinum electrocatalyst nanoparticles loaded on the substrate prepared in Example 1;
[0020] Figure 3 Transmission electron microscopy (TEM) image of the platinum nanoparticle electrocatalyst loaded on the substrate prepared in Example 1;
[0021] Figure 4The polarization curve of the nanoparticle platinum electrocatalyst supported on the substrate prepared in Example 1;
[0022] Figure 5 The stability curve of the nanoparticle platinum electrocatalyst supported on the substrate prepared in Example 1;
[0023] Figure 6 The polarization curves are for the nanoparticle platinum electrocatalyst supported on the substrate prepared in Example 2. Detailed Implementation
[0024] Specific implementation method one: Combining Figure 1 Specifically, this embodiment describes a method for rapidly preparing nanoparticle platinum electrocatalysts via thermal shock, which is as follows:
[0025] I. Pretreatment of the conductive substrate:
[0026] The conductive substrate is immersed in nitric acid and then heat-treated to obtain the pretreated substrate.
[0027] II. Loading the platinum source onto the substrate:
[0028] The platinum source was dissolved in ethanol to obtain a platinum source solution. The platinum source solution was then dropped onto the pretreated substrate and allowed to stand and dry to obtain a substrate loaded with the platinum source.
[0029] III. Rapid heating:
[0030] The two ends of the substrate loaded with the platinum source were clamped to the positive and negative terminals of a DC power supply, respectively. Under the condition of a current of 2A to 70A, the power was applied for 0.5s to 10s. Finally, the power was turned off and the sample was taken out to obtain the nanoparticle platinum electrocatalyst loaded on the substrate.
[0031] The beneficial effects of this embodiment are:
[0032] 1. This embodiment proposes a method for rapidly preparing nanoparticle platinum electrocatalysts via thermal shock. Nanoparticle platinum is uniformly loaded onto a substrate, eliminating the need for other reducing agents. This ensures the stability of the catalytic material while maintaining a low platinum loading, thus reducing costs.
[0033] 2. This preparation method is simple to operate, highly flexible, and significantly shortens the production cycle, which is conducive to large-scale industrial production. Compared with other production processes that take several to more than ten hours to prepare, the required heating time is only 0.5 to 10 seconds, which helps to reduce equipment occupancy time and significantly improve industrial production efficiency.
[0034] 3. This embodiment prepares a nanoparticle platinum electrocatalyst, introducing a large number of dislocations and heterojunction interfaces, which increases the number of active sites and thus enhances the catalyst's activity. Using the prepared platinum catalyst as the working electrode and a three-electrode testing system with a 1 mol / L KOH solution as the electrolyte, the HER reaction reached 10 mA / cm². 2 At a current density of only 19mV, the overpotential is greatly reduced, significantly improving energy consumption. Its performance is far superior to that of commercial carbon platinum, and its overpotential decay is negligible even after 24 hours, demonstrating remarkable catalytic stability.
[0035] Specific Implementation Method Two: This implementation method differs from Specific Implementation Method One in that the conductive substrate mentioned in step one is carbon fiber, carbon cloth, carbon felt, carbon paper, or carbon nanotube film. Everything else is the same as in Specific Implementation Method One.
[0036] Specific Implementation Method Three: This implementation method differs from Specific Implementation Method One or Two in that the heat treatment described in step one is specifically carried out at a temperature of 20℃ to 100℃ for 3 to 24 hours. Everything else is the same as in Specific Implementation Method One or Two.
[0037] Specific Implementation Method Four: This implementation method differs from Specific Implementation Methods One to Three in that the concentration of the platinum source solution mentioned in step two is 0.1 g / L to 1 g / L. Everything else is the same as in Specific Implementation Methods One to Three.
[0038] Specific Implementation Method Five: This implementation method differs from Specific Implementation Methods One to Four in that: in step two, the concentration is 0.05 mL / cm 2 ~0.5mL / cm 2 The platinum source solution is then dropped onto the pretreated substrate. Everything else is the same as in embodiments one through four.
[0039] Specific Implementation Method Six: This implementation method differs from Specific Implementation Methods One to Five in that the platinum source mentioned in step two is chloroplatinic acid, potassium chloroplatinate, or ammonium chloroplatinate. Everything else is the same as in Specific Implementation Methods One to Five.
[0040] Specific Implementation Method Seven: This implementation method differs from Specific Implementation Methods One to Six in that: in step three, electricity is applied under vacuum, air, argon, nitrogen, or hydrogen. Otherwise, it is the same as Specific Implementation Methods One to Six.
[0041] Specific Implementation Method Eight: This implementation method differs from Specific Implementation Methods One through Seven in that: in step three, the vacuum degree is 10... -1 Pa~10 -4 Under conditions of Pa and current of 2A to 70A, the current is applied for 0.5s to 10s. Other aspects are the same as in specific embodiments one to seven.
[0042] Specific Implementation Method Nine: This implementation method differs from Specific Implementation Methods One to Eight in that: in step three, under the condition of a current of 2A to 70A, the temperature is raised to 700℃ to 2200℃, and the temperature is maintained for 0.5s to 10s. Everything else is the same as Specific Implementation Methods One to Eight.
[0043] Specific Implementation Method Ten: This implementation method differs from Specific Implementation Methods One to Nine in that: in step three, under the condition of a current of 2A to 70A, the temperature is raised to 700℃ to 2200℃ at a heating rate of 1000K / s to 5000K / s, and then kept at that temperature for 0.5s to 10s. Everything else is the same as in Specific Implementation Methods One to Nine.
[0044] The beneficial effects of the present invention are verified using the following embodiments:
[0045] Example 1:
[0046] A method for rapidly preparing nanoparticle platinum electrocatalysts via thermal shock is provided, comprising the following steps:
[0047] I. Pretreatment of the conductive substrate:
[0048] The conductive substrate was immersed in nitric acid and heat-treated at 100°C for 3 hours. Then it was repeatedly washed with deionized water to obtain the pretreated substrate.
[0049] II. Loading the platinum source onto the substrate:
[0050] The platinum source was dissolved in ethanol to obtain a platinum source solution, and the solution was added dropwise at a rate of 0.3 mL / cm³. 2 The platinum source solution was dropped onto the pretreated substrate and allowed to stand and dry to obtain a substrate loaded with platinum source.
[0051] The concentration of the platinum source solution is 0.5 g / L;
[0052] III. Rapid heating:
[0053] The two ends of the substrate loaded with platinum source were clamped to the positive and negative terminals of a DC power supply, respectively. Under air atmosphere and current of 50A, the temperature was raised to 1800℃ at a heating rate of 2500K / s, and the power was applied and held for 2s. Finally, the power was turned off and the sample was taken out to obtain the nanoparticle platinum electrocatalyst loaded on the substrate.
[0054] The conductive substrate mentioned in step one is a carbon nanotube film, cut into 2cm×5cm pieces, then washed with deionized water, then ultrasonically cleaned with acetone for 10 minutes, and finally dried.
[0055] The platinum source mentioned in step two is chloroplatinic acid (H2PtCl6·6H2O).
[0056] Figure 2 This is a scanning electron microscope (SEM) image of the nanoparticle platinum electrocatalyst prepared in Example 1 and loaded onto a substrate. As shown in the image, the platinum nanoparticles are uniformly loaded onto the carbon nanotube film support material, eliminating the need for other reducing agents. This approach ensures the stability of the catalytic material while reducing the platinum loading and lowering costs.
[0057] Figure 3 The image shows a transmission electron microscope (TEM) image of the platinum nanoparticle electrocatalyst supported on the substrate prepared in Example 1. As can be seen from the image, a Pt / PtO2 heterostructure interface is formed, increasing the number of active sites and resulting in excellent electrocatalytic activity. The bonding at the Pt / PtO2 interface enhances the electron transfer rate, and the different band arrangements lead to charge transfer at the interface, which is beneficial for surface electron modulation of the heterostructure. This successfully modulates the conductivity, chemical stability, and active site density of the Pt / PtO2 heterostructure.
[0058] Figure 4 The polarization curves are shown for the nanoparticle platinum electrocatalyst supported on the substrate prepared in Example 1. The heterostructured nanoparticle platinum electrocatalyst was prepared by thermal shock, introducing a large number of heterojunction interfaces, which increases the number of active sites and thus enhances the catalyst's activity. Using the prepared platinum catalyst as the working electrode and a 1 mol / L KOH solution as the electrolyte in a three-electrode testing system, the HER reaction reached 10 mA / cm². 2 At current densities, only 19mV of overpotential is required, which greatly reduces energy consumption and its performance is far superior to commercial carbon platinum.
[0059] Figure 5 The stability curve of the platinum nanoparticle electrocatalyst supported on the substrate prepared in Example 1 is shown. A three-electrode testing system using a 1 mol / L KOH solution as the electrolyte was used to test the HER reaction at 10 mA / cm². 2 Under a current density of 24 h, its overpotential decay is minimal and negligible, demonstrating remarkable catalytic stability.
[0060] Example 2: This example differs from Example 1 in that the conductive substrate mentioned in step one is carbon cloth. Everything else is the same as in Example 1.
[0061] Figure 6 The polarization curves are shown for the platinum nanoparticle electrocatalyst supported on the substrate prepared in Example 2. Using the prepared platinum catalyst as the working electrode and a 1 mol / L KOH solution as the electrolyte, a three-electrode testing system was used to achieve a HER reaction rate of 10 mA / cm². 2 At current densities of , only an overpotential of 20mV is required.
Claims
1. A method for rapidly preparing nanoparticle platinum electrocatalysts via thermal shock, characterized in that... It is done in the following steps: I. Pretreatment of the conductive substrate: The conductive substrate was immersed in nitric acid and heat-treated at 100°C for 3 hours to obtain the pretreated substrate. II. Loading the platinum source onto the substrate: The platinum source was dissolved in ethanol to obtain a platinum source solution, and then dissolved at 0.05 mL / cm³. 2 ~0.5mL / cm 2 The platinum source solution was dropped onto the pretreated substrate and allowed to stand and dry to obtain a substrate loaded with platinum source. The concentration of the platinum source solution is 0.1 g / L to 1 g / L; the platinum source is chloroplatinic acid, potassium chloroplatinate, or ammonium chloroplatinate. III. Rapid heating: The two ends of the substrate loaded with platinum source were clamped to the positive and negative terminals of a DC power supply, respectively. Under the conditions of air atmosphere and current of 50A~70A, the temperature was raised to 1800℃~2200℃ at a heating rate of 2500K / s~5000K / s, and the power was applied for 2s~10s. Finally, the power was turned off and the sample was taken out to obtain the nanoparticle platinum electrocatalyst loaded on the substrate. The aforementioned nanoparticle platinum electrocatalyst supported on a substrate introduces a Pt / PtO2 heterojunction interface. Using a three-electrode testing system with a substrate-supported platinum nanoparticle electrocatalyst as the working electrode and a 1 mol / L KOH solution as the electrolyte, the HER reaction reached 10 mA / cm². 2 At the given current density, the overpotential is 19mV.
2. The method for rapidly preparing nanoparticle platinum electrocatalysts by thermal shock according to claim 1, characterized in that... The conductive substrate mentioned in step one is carbon fiber, carbon cloth, carbon felt, carbon paper, or carbon nanotube film.