AuPt alloy nanocluster with uniform size distribution and preparation method thereof
By using specific compounds and steps in the reaction system in water and toluene, AuPt alloy nanoclusters with uniform particle size and high stability are prepared, which solves the problems of high temperature energy consumption, high equipment costs and low yields in the prior art, and achieves efficient preparation suitable for catalysis and sensing.
Patent Information
- Application Number
- CN202510306146.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-14
- Publication Date
- 2025-06-27
AI Technical Summary
The existing AuPt alloy nanocluster preparation methods have problems such as high temperature energy consumption, high equipment costs, complex electrochemical conditions and low yield, resulting in uneven particle size distribution and poor stability.
The reaction system of compounds such as chloroauric acid, potassium tetrachloroplatinate and tetraoctyl ammonium bromide in water and toluene was prepared by stirring, standing, adding ligands and sodium borohydride.
The uniform particle size distribution and high stability of AuPt alloy nanoclusters are achieved, with an average particle size of 1.64nm, which is suitable for catalysis and sensing applications.
Smart Images
Figure HDA0005313011150000011 
Figure HDA0005313011150000012 
Figure HDA0005313011150000013
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of preparation of metal alloy nanoclusters, and particularly to a size-uniform AuPt alloy nanocluster and a preparation method thereof. Background Art
[0002] Nanoclusters generally refer to metal particles with 10 - 200 atoms and a diameter of 1 - 3 nm, which are a bridge connecting molecules and nanoparticles. Atomically precise alloy nanoclusters have great potential in regulating material properties and can deepen the understanding of many fundamental issues, such as doping sites, optimizing the properties of nanoclusters, and the correlation between structure and performance. In previous reports, Au 25 (SR) 18 has no catalytic activity in the electrocatalytic oxidation of formic acid reaction, but after doping Pt atoms, Au 24 Pt nanoclusters exhibit good catalytic activity, and the conversion rate is 12 times and 34 times higher than that of Pt nanoclusters and commercial Pt / C catalysts respectively [Nano Energy, 2018, 50:316]. Therefore, the efficient preparation of AuPt alloy nanoclusters has important research significance. Currently, methods for preparing AuPt alloy nanoclusters include thermal decomposition method, electrochemical method, etc. The thermal decomposition method forms alloy nanoclusters by thermally decomposing organic precursors of Au and Pt. High temperature is required in the preparation process, resulting in high energy consumption, and uneven particle size distribution is easily caused at high temperature. The electrochemical method forms alloy nanoclusters by electrochemically reducing precursors of Au and Pt, but its equipment cost is high, the electrochemical conditions are complex to control, affecting the product quality, and the yield is low, making it difficult to produce on a large scale. Summary of the Invention
[0003] Based on the above technical problems, the purpose of the present invention is to provide a preparation method of a size-uniform AuPt alloy nanocluster, with a simple and efficient preparation process, high product stability, and uniform particle size distribution.
[0004] To achieve the above invention purpose, the present invention adopts the following technical solutions:
[0005] The present invention provides a preparation method of a size-uniform AuPt alloy nanocluster, comprising the following steps:
[0006] (1) Dissolve chloroauric acid, potassium tetrachloroplatinate, and tetraoctylammonium bromide (TOAB) in H2O and toluene to obtain reaction system 1;
[0007] (2) After stirring reaction system 1 for 10 - 40 minutes, let it stand for 5 - 10 minutes, remove the aqueous phase to obtain reaction system 2;
[0008] (3) adding the ligand to the reaction system 2, stirring at 20 to 30° C. for 10 to 30 minutes, to obtain the reaction system 3;
[0009] (4) Add sodium borohydride to the reaction system 3, react at 20-30° C. for 2-3 days, and obtain AuPt alloy nanoclusters as products.
[0010] In the above technical solution, further, in the step (1), the molar ratio of chloroauric acid, potassium tetrachloroplatinate, TOAB, H2O and toluene is 1:(0.2-0.4):(1-5):(5-10):(10-20).
[0011] In the above technical solution, further, in the step (3), the ligand is a thiol ligand, and the thiol ligand includes phenylethyl mercaptan, adamantane thiol, etc.; the added amount of the ligand is 5 to 8 times that of chloroauric acid in terms of molar ratio.
[0012] In the above technical solution, further, in the step (4), the amount of sodium borohydride added is 25 to 30 times that of chloroauric acid in terms of molar ratio.
[0013] The present invention provides AuPt alloy nanoclusters prepared by the above-mentioned preparation method, which have uniform size distribution, an average particle size of 1.6-1.8nm and high stability.
[0014] In the above technical solution, further, the average particle size is 1.64 nm.
[0015] Compared with the prior art, the present invention has the following beneficial effects:
[0016] (1) The present invention simply prepares AuPt alloy nanoclusters with controllable atomic number and uniform size distribution, the size of which is uniformly distributed between 1.12 and 2.12 nm, and the average particle size is 1.64 nm; the method of the present invention is feasible, simple to operate, and easy to control.
[0017] (2) The AuPt alloy nanoclusters synthesized in the present invention have high stability and uniform particle size distribution, which is beneficial to improving their catalytic performance and can be applied to catalysis, sensing and other aspects, providing a basis for exploring the application and development of alloy nanoclusters. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 UV-Vis spectrum of the product obtained in Example 1.
[0019] Figure 2 Transmission electron microscopy image and particle size distribution of the product obtained in Example 1.
[0020] Figure 3TEM image and particle size distribution of the product obtained in Example 1 after standing at 30 °C for 168 h.
[0021] Figure 4 UV-Vis spectrum of the product obtained in Comparative Example 1. Detailed implementation manners
[0022] The present invention will be further described below in conjunction with specific embodiments, but the present invention is not limited in any way.
[0023] Example 1
[0024] (1) Add 82.4 mg of HAuCl4·4H2O (0.2 mmol), 24.9 mg of K2PtCl4 (0.06 mmol), 5 mL of H2O and 10 mL of toluene to a 50 mL round-bottom flask, and then add 131.2 mg of TOAB (0.24 mmol).
[0025] (2) After stirring for 30 min, let it stand for 5 minutes. The solution is divided into two phases. The upper layer is the aqueous phase, and the aqueous phase is removed.
[0026] (3) Add 201.6 mg of HS-Adam ligand (1.2 mmol) to the solution in (2), and stir at 20 °C for 30 minutes.
[0027] (4) After 1 h, dissolve 189 mg of NaBH4 (5 mmol) in 5 mL of ice water and add it to the solution.
[0028] (5) After the reaction proceeds for 48 h, stop the reaction, wash the crude product with a large amount of methanol, and extract it with acetone solvent to obtain AuPt alloy nanoclusters with a uniform size distribution.
[0029] The UV-Vis spectrum of the AuPt alloy nanoclusters is as Figure 1 shown, with two characteristic absorption peaks at 440 nm and 650 nm, proving the formation of AuPt alloy nanoclusters.
[0030] The TEM image and particle size distribution of the AuPt alloy nanoclusters are as Figure 2 shown, and their sizes are uniformly distributed between 1.12 and 2.12 nm, with an average particle size of 1.64 nm.
[0031] The obtained AuPt alloy nanoclusters were subjected to a stability test. After standing at 30 °C for 168 h, a TEM test was carried out. The TEM image and particle size distribution are as Figure 3 shown, and their sizes are uniformly distributed, without obvious agglomeration. The particle sizes are between 1.15 and 2.51 nm, and the average particle size is 1.72 nm.
[0032] Comparative Example 1
[0033] The difference from the preparation method of Example 1 is only that the HS-Adam ligand is not added in step (3).
[0034] (1) Add 82.4 mg of HAuCl4·4H2O (0.2 mmol), 24.9 mg of K2PtCl4 (0.06 mmol), 5 mL of H2O and 10 mL of toluene to a 50 mL round-bottom flask, and then add 131.2 mg of TOAB (0.24 mmol).
[0035] (2) After stirring for 30 min, let it stand for 5 minutes. The solution is divided into two phases. The upper layer is the aqueous phase, and the aqueous phase is removed.
[0036] (3) After 1 h, dissolve 189 mg of NaBH4 (5 mmol) in 5 mL of ice water and add it to the solution.
[0037] (4) After the reaction proceeds for 48 h, stop the reaction. Wash the crude product with a large amount of methanol and extract it with acetone solvent.
[0038] The product was tested by ultraviolet-visible absorption spectroscopy. As Figure 4 shown, no characteristic absorption peak was shown, proving that no AuPt alloy nanoclusters were formed.
Claims
1. A method for preparing AuPt alloy nanoclusters with uniform size distribution, characterized in that: The preparation method comprises the following steps: (1) dissolving chloroauric acid, potassium tetrachloroplatinate and TOAB in H2O and toluene to obtain a reaction system 1; (2) stirring the reaction system 1 for 10 to 40 minutes, allowing it to stand for 5 to 10 minutes, and removing the aqueous phase to obtain a reaction system 2; (3) adding the ligand to the reaction system 2, stirring at 20 to 30° C. for 10 to 30 minutes, to obtain the reaction system 3; (4) Add sodium borohydride to the reaction system 3, react at 20-30° C. for 2-3 days, and obtain AuPt alloy nanoclusters as products.
2. The preparation method according to claim 1, characterized in that: In the step (1), the molar ratio of chloroauric acid, potassium tetrachloroplatinate, TOAB, H2O and toluene is 1:(0.2-0.4):(1-5):(5-10):(10-20).
3. The preparation method according to claim 1, characterized in that: In the step (3), the ligand is a thiol ligand, and the thiol ligand includes phenylethyl mercaptan and adamantane thiol; the amount of the ligand added is 5 to 8 times that of chloroauric acid in terms of molar ratio.
4. The preparation method according to claim 1, characterized in that: In the step (4), the amount of sodium borohydride added is 25 to 30 times that of chloroauric acid in terms of molar ratio.
5. The AuPt alloy nanoclusters prepared by the preparation method according to any one of claims 1 to 4.
6. The AuPt alloy nanocluster according to claim 5, characterized in that: The AuPt alloy nanoclusters have uniform size distribution and an average particle size of 1.6-1.8 nm.