Alloy nanocluster and preparation method and application thereof

Abstract

The invention provides an alloy nanocluster as well as a preparation method and application thereof. The molecular formula of the alloy nanocluster is [Cu10Pt3X5Y6]. Z, X is an alkyne ligand, Y is a nitrogen phosphine ligand, and Z is an anion. Therefore, the alloy nanocluster can enable Pt atoms to be accurately doped on the surface of the cluster, and the catalytic activity of the cluster is improved. In addition, the Cu-Cu bond distance in the alloy nanocluster is short, and the alloy nanocluster has excellent thermodynamic stability and chemical stability.

Description

Technical Field

[0001] The present invention relates to the technical field of materials, and specifically, to alloy nanoclusters and their preparation methods and applications. Background Art

[0002] Atomically precise alloy nanoclusters have become a research hotspot of novel nanomaterials due to their tunable electronic structures, optical properties, and catalytic performances. When exploring the structure-property relationships of alloy clusters, it is crucial to precisely control the number and position of doped atoms. In a system with coexisting multi-metal cations, the synthesis process of alloy nanoclusters is extremely complex, and their polydispersity and gradient doping effects pose challenges to the synthesis and crystallization of monodisperse alloy nanoclusters. Existing studies have shown that Group XI metals (such as Cu, Ag, and Au) can form alloy clusters with each other, such as [Au 16 Cu 6 , [Ag 4 Cu 15] , [Au@Cu 14 , [Au 19 Cu 30 , [AgnAu 25-n (n = 1 - 13)], [CunAg 8 Au 7-n (n = 1 - 6)]. However, the research on Group XI metal-based alloy clusters involving doping with other metals is relatively scarce. Typical examples include [Pt 1 Ag 18] , [Pt 1 Ag 16 , [(RhH) / Ni / Pd / Pt / Au@Ag 24 , [Cd 12 Ag 32 , [Hg 1 Au 24 (SR) 18 . All Pd- and Pt-doped alloy clusters have a more thermodynamically stable central doping structure. Theoretical calculations show that the d electrons of Group X metals in the central doping exhibit relatively high stability.

[0003] Compared with Au and Ag clusters, Cu has become an important candidate material for developing new alloy cluster catalysts due to its high abundance, low cost, and unique catalytic properties. Although there have been a few reports on atomically precise group-X metal-doped Cu alloy clusters, synthesizing stable Cu alloy clusters still faces many challenges. In particular, due to the relatively low standard reduction potential of Cu(I)→Cu(0) (0.52 V), and the significant atomic size difference between Cu and Pt (Cu: 140 pm, Pt: 175 pm), the synthesis of Pt-doped Cu clusters remains extremely difficult. For cluster catalytic applications, an ideal doping strategy should expose noble metal (such as Pt and Pd) active sites on the cluster surface so that substrates and intermediates can contact them more efficiently.

[0004] Therefore, synthesizing alloy nanoclusters with atomically precise surface Pt doping is expected to design highly efficient nanocatalysts. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art to some extent. To this end, an object of the present invention is to provide an alloy nanocluster (Cu 10 Pt 3 ), in which platinum atoms (Pt) are precisely doped on the surface of the cluster, and these surface-exposed Pt atoms are ideal active sites for the hydrogen evolution reaction (HER). Pt atoms can efficiently adsorb and desorb hydrogen atoms, thereby significantly reducing the activation energy of the reaction and improving the catalytic efficiency. In addition, the Cu 10 Pt 3 has a short Cu-Cu bond distance (average ), indicating a strong metal-metal bond. This strong bonding improves the thermodynamic and chemical stability of the alloy nanocluster.

[0006] Therefore, in the first aspect of the present invention, the present invention provides an alloy nanocluster. According to an embodiment of the present invention, the molecular formula of the alloy nanocluster is [Cu 10 Pt 3 X 5 Y 6 ·Z, where X is an alkyne ligand, Y is a nitrogen-phosphorus ligand, and Z is an anion. Thus, the alloy nanocluster of the present invention can precisely dope Pt atoms on the surface of the cluster, improving the catalytic activity of the cluster. In addition, the short Cu-Cu bond distance in the alloy nanocluster improves the thermodynamic and chemical stability of the alloy nanocluster.

[0007] According to an embodiment of the present invention, the alloy nanocluster may further include at least one of the following additional technical features:

[0008] According to an embodiment of the present invention, the alkyne ligand includes phenylacetylene.

[0009] According to an embodiment of the present invention, the nitrogen-phosphorus ligand includes diphenyl-2-pyridylphosphine

[0010] According to an embodiment of the present invention, the anion includes F - , Cl - , Br - , ClO 4- , PF 6- , OTF - , BF 4- , SbF 6- , NO 3- , CH 3 COO - , CF 3 , SO 3- , CuCl 2 - at least one of them.

[0011] According to an embodiment of the present invention, platinum atoms are distributed on the surface of the alloy nanocluster structure.

[0012] In a second aspect of the present invention, the present invention provides a method for preparing the alloy nanoclusters described in the first aspect. According to an embodiment of the present invention, the method includes: performing a first mixing treatment on a copper source, an alkyne ligand, and a first solvent to obtain a first solution; adding a basic solvent to the first solution to obtain a second solution; performing a rotary evaporation treatment and a washing treatment on the second solution to obtain a first solid; performing a second mixing treatment on the first solid, a nitrogen-phosphorus ligand, and a second solvent to obtain a third solution; adding a platinum source to the third solution to obtain a fourth solution; performing a third mixing treatment on the fourth solution and a reducing solution to obtain a solution containing alloy nanoclusters. Thus, through the above method, Cu nanoclusters doped with Pt atoms on the surface can be synthesized under mild conditions. This synthesis strategy realizes the precise doping of Pt atoms on the surface of the cluster, enabling the full exposure of Pt active sites. In catalytic applications, this helps the substrate and intermediates to contact the Pt active sites more efficiently, thereby significantly improving the catalytic activity and enhancing the overall catalytic efficiency.

[0013] According to an embodiment of the present invention, the method for preparing the alloy nanoclusters may further include at least one of the following additional technical features:

[0014] According to an embodiment of the present invention, it further includes: performing precipitation, centrifugation, and crystallization treatments on the solution containing alloy nanoclusters to obtain the crystals of the alloy nanoclusters.

[0015] According to an embodiment of the present invention, the molar ratio of the copper source to the alkyne ligand is 1:(0.8 - 1.2).

[0016] According to an embodiment of the present invention, the molar concentration of the copper source in the first solution is 0.1 - 0.2 mmol / mL.

[0017] According to an embodiment of the present invention, the copper source is selected from Cu(CH 3 CN) 4 Z 1 , where Z 1 is an anion, and the anion includes F - , Cl - , Br - , ClO 4- , PF 6- , OTF - , BF 4- , SbF 6- , NO 3- , CH 3 COO - , CF 3 SO 3- and at least one of them.

[0018] According to an embodiment of the present invention, the alkyne ligand is selected from phenylacetylene.

[0019] According to an embodiment of the present invention, the first solvent is selected from at least one of dichloromethane, chloroform, methanol, acetone, tetrahydrofuran, and ethanol.

[0020] According to an embodiment of the present invention, the molar ratio of the basic solvent to the copper source is 1:(0.5 - 2).

[0021] According to an embodiment of the present invention, the basic solvent is selected from triethylamine.

[0022] According to an embodiment of the present invention, the washing treatment is carried out with at least one of n-hexane, ethanol, and ether.

[0023] According to an embodiment of the present invention, the molar ratio of the first solid to the nitrogen-phosphorus ligand is 1:(0.3 - 0.8).

[0024] According to an embodiment of the present invention, the molar concentration of the first solid in the third solution is 0.01 - 0.05 mmol / mL.

[0025] According to an embodiment of the present invention, the concentration of the platinum source in the fourth solution is 0.001 - 0.004 mmol / mL.

[0026] According to an embodiment of the present invention, the nitrogen-phosphorus ligand is selected from diphenyl-2-pyridylphosphine.

[0027] According to an embodiment of the present invention, the second solvent is selected from toluene and benzene.

[0028] According to an embodiment of the present invention, the platinum source is selected from potassium chloroplatinate and sodium chloroplatinate.

[0029] According to an embodiment of the present invention, the reducing solution is selected from an ethanol solution and a methanol solution containing sodium borohydride.

[0030] According to an embodiment of the present invention, the precipitation is carried out using at least one of n-hexane, n-pentane, petroleum ether, and n-heptane.

[0031] According to an embodiment of the present invention, the crystallization treatment is carried out using at least one of n-hexane, n-pentane, petroleum ether, and n-heptane.

[0032] In a third aspect of the present invention, the present invention provides the use of the alloy nanoclusters described in the first aspect or the alloy nanoclusters prepared by the method described in the second aspect in electrocatalytic hydrogen evolution. As described above, the Pt atoms in the alloy nanoclusters of the present invention are doped on the surface of the clusters, which can fully expose the Pt active sites, helping the substrate and intermediates to contact the Pt active sites more efficiently, thereby improving the catalytic activity and enhancing the overall catalytic efficiency.

[0033] The additional aspects and advantages of the present invention will be partly given in the following description, partly will become apparent from the following description, or will be understood through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the description of the embodiments in conjunction with the following drawings, wherein:

[0035] Figure 1 is a schematic diagram of the metal core structure of Cu 10 Pt 3 according to an embodiment of the present invention;

[0036] Figure 2 is a schematic diagram of the single crystal structure of Cu 10 Pt 3 according to an embodiment of the present invention;

[0037] Figure 3 is a flowchart of the method for preparing alloy nanoclusters according to an embodiment of the present invention;

[0038] Figure 4 is a mass spectrum of Cu 10 Pt 3 according to an embodiment of the present invention;

[0039] Figure 5 is a schematic diagram of Cu according to an embodiment of the present invention10 Pt 3 Linear voltammetry curve of electrocatalytic hydrogen evolution Detailed implementation mode

[0040] The embodiments of the present invention are described in detail below, which are intended to explain the present invention and should not be construed as a limitation to the present invention.

[0041] Referring to "embodiments" herein means that the specific features, structures or characteristics described in connection with the embodiments can be included in at least one embodiment of the present invention. The phrase appears at various positions in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0042] For the sake of brevity, only some numerical ranges are specifically disclosed herein. However, any lower limit can be combined with any upper limit to form a range not explicitly recited; and any lower limit can be combined with other lower limits to form a range not explicitly recited, and similarly any upper limit can be combined with any other upper limit to form a range not explicitly recited. In addition, each individually disclosed point or single numerical value itself can be used as a lower limit or an upper limit and combined with any other point or single numerical value or combined with other lower limits or upper limits to form a range not explicitly recited.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this invention belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention; the terms "comprising" and "having" and any variations thereof in the specification and claims of the present invention and the above drawings are intended to cover non-exclusive inclusion.

[0044] In this article, the term "comprising" or "including" is an open expression, that is, it includes the content specified by the present invention, but does not exclude other aspects.

[0045] It should be noted that the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. Further, in the description of the present invention, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0046] Among alloy nanoclusters, copper-based clusters show significant potential for catalytic applications due to their high abundance, low cost, and unique catalytic properties. However, due to the low standard reduction potential of Cu(I)→Cu(0) (0.52V) and the large difference in atomic size between Cu (140pm) and Pt (175pm), the synthesis of Pt-doped copper clusters is particularly challenging. For example, in 2021, Hyeon et al. reported the first Pt-doped copper nanocluster [Pt 2 Cu 34 (PET) 22 C l4 ] 2- (PET = 2-phenylethanethioate), which has an interpenetrating icosahedral core (Pt 2 Cu 18 ). Subsequently, Lu et al. synthesized PtCu with near-infrared (NIR) emission. 18 alloy nanoclusters. Nevertheless, the platinum atoms in these clusters are mostly located in the interior and lack surface-exposed active sites. Although non-surface atoms can also affect catalytic performance, surface catalysis dominates in catalytic science. The ideal doping strategy is to expose noble metal active sites on the cluster surface, thereby improving the accessibility of substrates and intermediates. Therefore, the synthesis of alloy nanoclusters with atomically precise surface platinum doping has become a key issue to be solved in the field of cluster catalysis.

[0047] In view of this, the inventors of the present invention have developed a new type of alloy nanocluster after a lot of experiments. Single crystal X-ray diffraction analysis shows that the cluster has a distorted cubic octahedron Cu 10 Pt 3 In the core, platinum atoms (Pt) are located along the C 3 The axes are strategically distributed around the middle layer, achieving precise doping of Pt atoms on the surface of the cluster. This unique structural design enables the surface Pt active sites to efficiently adsorb and desorb hydrogen atoms, reducing the reaction activation energy and thus improving the catalytic efficiency. In addition, Cu 10 Pt 3 The average Cu-Cu bond distance is The shorter bond length indicates that the metal-metal bond is strong, which further enhances the thermodynamic and chemical stability of the alloy nanoclusters. The alloy nanoclusters, the method for preparing the alloy nanoclusters and their uses are introduced in detail below.

[0048] Alloy Nanoclusters

[0049] In the first aspect of the present invention, the present invention provides an alloy nanocluster. According to an embodiment of the present invention, the molecular formula of the alloy nanocluster is [Cu 10 Pt 3 X 5 Y6 ·Z, where X is an alkyne ligand, Y is a nitrogen-phosphorus ligand, and Z is an anion. Thus, the alloy nanoclusters of the present invention can precisely dope Pt atoms on the surface of the clusters, improving the catalytic activity of the clusters. In addition, the Cu-Cu bond distance in the alloy nanoclusters is short, having excellent thermodynamic stability and chemical stability.

[0050] In some embodiments of the present invention, the alloy nanoclusters [Cu 10 Pt 3 X 5 Y 6 ·Z, the crystal structure schematic diagram of the metal core [Cu 10 Pt 3 can be referred to Figure 1 . It can be seen from the figure that the metal core is a distorted cubic octahedron, in which platinum atoms (Pt) are precisely distributed on the periphery of the middle layer along the C 3 axis, realizing the precise doping of Pt atoms on the surface of the clusters. The single crystal structure schematic diagram of the alloy nanoclusters [Cu 10 Pt 3 X 5 Y 6 ·Z can be referred to Figure 2 . The alloy nanoclusters are composed of a cationic cluster and a counter anion. The cationic cluster core has 3 Pt and 10 Cu metal atoms, which are stabilized by 5 alkynyl ligands and 6 dppy (diphenyl-2-pyridylphosphine) ligands, forming [Cu 10 Pt 3 (PhC≡C) 5 (dppy) 6 + .

[0051] In some embodiments of the present invention, the alkyne ligand includes phenylacetylene. Thus, the alkyne ligand can combine with the metal core [Cu 10 Pt 3 to form stable alloy nanoclusters, and ensure that the alloy nanoclusters have high catalytic activity.

[0052] In some embodiments of the present invention, the nitrogen-phosphorus ligand includes diphenyl-2-pyridylphosphine. Thus, the nitrogen-phosphorus ligand can combine with the metal core [Cu 10 Pt 3 to form stable alloy nanoclusters, and ensure that the alloy nanoclusters have high catalytic activity.

[0053] In some embodiments of the present invention, the molecular formula of the alloy nanoclusters is [Cu 10 Pt 3 (PhC≡C) 5 (dppy)​6 ·Z。

[0054] In some embodiments of the present invention, the anion includes F - , Cl - , Br - , ClO 4- , PF 6- , OTF - , BF 4- , SbF 6- , NO 3- , CH 3 COO - , CF 3 , SO 3- , CuCl 2 - among at least one of them. Thus, the above anions can combine with the cation [Cu 10 Pt 3 X 5 Y 6 + to form a stable alloy nanocluster, and ensure that the alloy nanocluster has high catalytic activity.

[0055] It should be noted that the source of the anion of the alloy nanocluster of the present invention is diverse. On the one hand, the anion can directly come from the selected copper source raw material. When these raw materials decompose or participate in the reaction in the reaction system, specific anions will be released. On the other hand, the anion can also be generated in situ during the reaction, that is, under specific conditions of the synthesis reaction, some reactants or intermediates will undergo chemical transformation to generate the required anion.

[0056] In some embodiments of the present invention, platinum atoms are distributed on the surface of the alloy nanocluster structure. Thus, the catalytic activity of the alloy nanocluster can be improved, and the catalytic efficiency can be enhanced.

[0057] Method for preparing alloy nanoclusters

[0058] In the second aspect of the present invention, the present invention provides a method for preparing the alloy nanoclusters described in the first aspect. According to the embodiments of the present invention, referring to Figure 3 , the method for preparing alloy nanoclusters includes:

[0059] S100: Perform a first mixing treatment on a copper source, an alkyne ligand, and a first solvent

[0060] In this process, the copper source, the alkyne ligand, and the first solvent are subjected to a first mixing treatment to obtain a first solution.

[0061] ​In some embodiments of the present invention, the molar ratio of the copper source to the alkyne ligand is 1:(0.8 - 1.2). For example, it can be 1:0.8, 1:0.9, 1:1, 1:1.1, 1:1.2, etc., or it can be a range composed of any of the above values. Thus, by making the molar ratio of the copper source to the alkyne ligand within the above range, the alkyne ligand can stably and modify the alloy nanoclusters well, which is beneficial to improving the stability of the alloy nanoclusters; it can also maximize the reaction efficiency of the copper source and the alkyne ligand without causing excessive waste of one of the raw materials.

[0062] It should be noted that those skilled in the art can flexibly select the dosage of the first solvent according to the actual situation, as long as the copper source and the alkyne ligand can be effectively dissolved, but it should not be excessive, resulting in low concentrations of each component in the solution. In some embodiments of the present invention, the molar concentration of the copper source in the first solution is 0.1 - 0.2 mmol / mL. For example, it can be 0.1 mmol / mL, 0.12 mmol / mL, 0.14 mmol / mL, 0.16 mmol / mL, 0.18 mmol / mL, 0.2 mmol / mL, etc., or it can be a range composed of the above values.

[0063] In some embodiments of the present invention, the copper source is selected from Cu(CH 3 CN) 4 Z 1 where Z 1 is an anion, and the anion includes F - 、Cl - 、Br - 、ClO 4- 、PF 6- 、OTF - 、BF 4- 、SbF 6- 、NO 3- 、CH 3 COO - 、CF 3 SO 3- at least one of them.

[0064] In some embodiments of the present invention, the alkyne ligand is selected from phenylacetylene.

[0065] In some embodiments of the present invention, the first solvent is selected from at least one of dichloromethane, chloroform, methanol, acetone, tetrahydrofuran, and ethanol. Thus, the copper source and the alkyne ligand can be dissolved well, ensuring the smooth progress of the synthesis reaction and a good reaction rate.

[0066] S200: Add a basic solvent to the first solution

[0067] In this process, an alkaline solvent is added to the first solution obtained after the first mixing treatment to obtain a second alkaline solution.

[0068] Among them, the addition amount of the alkaline solution can be calculated by those skilled in the art according to the actual situation and can be appropriately added in excess as long as it meets the usage requirements of the process of the present invention. In some embodiments of the present invention, the molar ratio of the alkaline solvent to the copper source is 1:(0.5 - 2). For example, it can be 1:0.5, 1:0.8, 1:1, 1:1.2, 1:1.5, 1:1.8, 1:2, etc., or it can be a range composed of the above values. Thus, by making the molar ratio of the alkaline solvent to the copper source within the above range, the solution can be made alkaline, which is beneficial to the formation of deprotonated alkynyl ligands by the alkynyl ligand, thereby promoting its coordination reaction with the copper source.

[0069] In some embodiments, the alkaline solvent is triethylamine. Thus, the addition of triethylamine can remove the proton of the alkynyl ligand to generate deprotonated alkynyl ligands, thereby promoting its coordination reaction with the copper source.

[0070] S300: Perform rotary evaporation treatment and washing treatment on the second solution

[0071] In this process, the above-mentioned alkaline second solution is subjected to rotary evaporation treatment and washing treatment to obtain a first solid.

[0072] In some embodiments of the present invention, the second solution is first subjected to rotary evaporation treatment, and then the product of the rotary evaporation treatment is subjected to washing treatment to obtain a first solid.

[0073] In some embodiments of the present invention, the washing treatment is carried out using at least one of n-hexane, ethanol, and ether.

[0074] S400: Perform a second mixing treatment on the first solid, the nitrogen-phosphorus ligand, and the second solvent

[0075] In this process, the first solid, the nitrogen-phosphorus ligand, and the second solvent are subjected to a second mixing treatment to obtain a third solution.

[0076] In some embodiments of the present invention, the molar ratio of the first solid to the nitrogen-phosphorus ligand is 1:(0.3 - 0.8). For example, it can be 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, etc., or it can be a range composed of the above values. Thus, by making the molar ratio of the first solid to the nitrogen-phosphorus ligand within the above range, the nitrogen-phosphorus ligand can stably and modify the alloy nanoclusters well, which is beneficial to improving the stability of the alloy nanoclusters; it can also maximize the reaction efficiency of the first solid and the nitrogen-phosphorus ligand without causing excessive waste of one of the raw materials.

[0077] In some embodiments of the present invention, the nitrogen-phosphorus ligand is selected from diphenyl-2-pyridylphosphine. Thus, the above nitrogen-phosphorus ligand can well stabilize and modify the alloy nanoclusters, which is beneficial to improving the stability of the alloy nanoclusters.

[0078] It should be noted that those skilled in the art can flexibly select the amount of the second solvent according to the actual situation, as long as the first solid and the nitrogen-phosphorus ligand can be effectively dissolved, but it should not be excessive, resulting in too low concentrations of each component in the solution. In some embodiments of the present invention, the molar concentration of the first solid in the third solution is 0.01 - 0.05 mmol / mL. For example, it can be 0.01 mmol / mL, 0.02 mmol / mL, 0.03 mmol / mL, 0.04 mmol / mL, 0.05 mmol / mL, etc., or it can be a range composed of any of the above values.

[0079] In some embodiments of the present invention, the second solvent is selected from at least one of toluene and benzene. Thus, the first solid and the nitrogen-phosphorus ligand can be better dissolved, ensuring the smooth progress of the synthesis reaction and a good reaction rate.

[0080] S500: Add a platinum source to the third solution

[0081] In this process, by adding a platinum source to the third solution and stirring, a fourth solution is obtained.

[0082] In some embodiments of the present invention, the platinum source is selected from potassium chloroplatinate and sodium chloroplatinate. In some embodiments of the present invention, the concentration of the platinum source in the fourth solution is 0.001 - 0.004 mmol / mL. For example, it can be 0.001 mmol / mL, 0.002 mmol / mL, 0.003 mmol / mL, 0.004 mmol / mL, etc., or it can be a range composed of any of the above values. Thus, by making the platinum source within the above concentration range, platinum atoms can be precisely doped on the surface of the alloy nanoclusters, improving the catalytic activity of the alloy nanoclusters.

[0083] S600: Perform a third mixing treatment on the fourth solution and a reducing solution

[0084] In this process, the above fourth solution and the reducing solution are subjected to a third mixing treatment and stirred to obtain a solution containing alloy nanoclusters.

[0085] In some embodiments of the present invention, the reducing solution is selected from ethanol solutions and methanol solutions containing sodium borohydride. Among them, the concentration of sodium borohydride in the ethanol solution containing sodium borohydride is 8-12 mg / mL, for example, it can be 8 mg / mL, 9 mg / mL, 10 mg / mL, 11 mg / mL, 12 mg / mL, etc., or it can be a range composed of any of the above values. Thus, within the above parameter range, sodium borohydride as a reducing agent can fully cause the metal ions to undergo a reduction reaction, so that alloy nanoclusters can be prepared through the reduction reaction. Among them, after adding the ethanol solution of sodium borohydride to the fourth solution, the color of the solution gradually turns dark red, that is, the finally obtained solution containing alloy nanoclusters is dark red.

[0086] Among them, there is no special requirement for the addition amount of the ethanol solution containing sodium borohydride, and those skilled in the art can flexibly select according to the actual situation of the specific reaction. In some embodiments, the molar ratio of the first solid to sodium borohydride is 1:(2-3), for example, it can be 1:2, 1:2.2, 1:2.4, 1:2.6, 1:2.8, 1:3, etc., or it can be a range composed of any of the above values. In addition, the stirring time in this step can be 2-3 hours.

[0087] In some embodiments of the present invention, the method for preparing alloy nanoclusters further includes: precipitating, centrifuging, and crystallization treating the solution containing the alloy nanoclusters to obtain the crystals of the alloy nanoclusters.

[0088] In some embodiments of the present invention, the precipitation is carried out using at least one of n-hexane, n-pentane, petroleum ether, and n-heptane. That is, at least one of n-hexane, n-pentane, petroleum ether, and n-heptane is added to the solution containing the alloy nanoclusters. Thus, the alloy nanoclusters can be precipitated from the solution and form solid particles.

[0089] In some embodiments of the present invention, the crystallization treatment is carried out in the following manner: a certain amount of good solvent (such as CH 2 Cl 2 ) is added to the centrifuged product, and at the same time, a poor solvent (such as n-hexane) is covered on the upper layer of the centrifuged product for diffusion to obtain crystals, that is, the crystals of the alloy nanoclusters. Among them, there is no special requirement for the specific types of the good solvent and the poor solvent used for diffusion, and those skilled in the art can flexibly select according to the actual situation as long as it can meet the use requirements of the process of the present invention. In some embodiments, the good solvent includes but is not limited to at least one of dichloromethane, chloroform, acetone, and tetrahydrofuran, and the poor solvent includes but is not limited to at least one of n-hexane, n-pentane, n-pentane, petroleum ether, and n-heptane; the diffusion time can be 5-10 days.

[0090] Thus, through the above method, Cu nanoclusters doped with surface Pt atoms can be synthesized under mild conditions. This synthesis strategy realizes the precise doping of Pt atoms on the cluster surface, enabling the full exposure of Pt active sites. In catalytic applications, this helps the substrate and intermediates to contact the Pt active sites more efficiently, thereby significantly improving the catalytic activity and enhancing the overall catalytic efficiency.

[0091] Use

[0092] In the third aspect of the present invention, the present invention proposes the use of the alloy nanoclusters described in the first aspect or the alloy nanoclusters prepared by the method described in the second aspect in electrocatalytic hydrogen evolution. As described above, the Pt atoms doped on the cluster surface of the alloy nanoclusters of the present invention can enable the full exposure of Pt active sites, which helps the substrate and intermediates to contact the Pt active sites more efficiently, thereby improving the catalytic activity and enhancing the overall catalytic efficiency.

[0093] The embodiments of the present invention will be 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. For those not specified in the embodiments, the techniques or conditions described in the literature in the art or according to the product specifications are followed. For the reagents or instruments not specified by the manufacturer, they are all conventional products that can be obtained through commercial purchase.

[0094] Example 1

[0095] Preparation of alloy nanoclusters (Cu 10 Pt 3 ) specific steps:

[0096] 1. First, prepare copper phenylacetylene. Dissolve Cu(CH 3 CN) 4 PF 6 (315 mg, 1 mmol) and phenylacetylene (1 mmol, 110 μL) in a mixed solution of 4 mL of dichloromethane and 2 mL of methanol, add 200 μL of Et 3 N (triethylamine) and stir for 1 h. Then spin-dry, and wash the spin-dried material with n-hexane, ethanol, and ether in sequence to obtain 153 mg of copper phenylacetylene (yield 95.6%).

[0097] 2. Take 1 mmol, 160 mg of copper phenylacetylene and 0.5 mmol, 130 mg of dppy (diphenyl-2-pyridylphosphine), disperse them in 30 mL of toluene, then add 30 mg of potassium chloroplatinate, stir for 30 min, and then add a freshly prepared ethanol solution of sodium borohydride (100 mg of sodium borohydride dissolved in 10 mL of ethanol), and stir for 2.5 hours until a black-red clear solution is obtained.

[0098] 3. Add 150 mL of n - hexane to the black - red clear solution for precipitation, and then centrifuge and wash. Take 10 mg of the centrifuged precipitate and extract it with 2 mL of DCM (dichloromethane). Diffuse it with n - hexane. After one week, 2 mg of black - red block - shaped crystals are obtained (yield 31%, based on Pt). The black - red block - shaped crystals are crystals of alloy nanocluster Cu 10 Pt 3 .

[0099] Example 2

[0100] Characterize the physical properties of the prepared alloy nanocluster Cu 10 Pt 3 .

[0101] 1. Perform mass spectrometry analysis on the crystals of alloy nanocluster Cu 10 Pt 3 . As shown, the mass spectrometry shows that in the positive - ion mode, there is a significant peak with a characteristic peak spacing of 0.5 at m / z = 1653.5. After identification, this peak is [Cu Figure 4 10 Pt 3 (PhC≡C)(dppy) 5 (dppy) 6 H] 2+ . The isotope distribution pattern is consistent with the simulation result ( Figure 4 inset). This result not only confirms the chemical composition of the cluster but also the charge state of the cluster determined by single - crystal XRD.

[0102] 2. Perform XRD analysis on the crystals of alloy nanocluster Cu 10 Pt 3 . The schematic diagram of the single - crystal structure can be referred to Figure 2 . The result shows that the alloy nanocluster consists of a cationic cluster and a counter - anion. The core of the cationic cluster has 3 Pt and 10 Cu metal atoms, which are stabilized by 5 alkynyl ligands and 6 dppy ligands, forming [Cu 10 Pt 3 (PhC≡C) 5 (dppy) 6 + .

[0103] 3. The schematic diagram of the crystal structure of the metal core [Cu 10 Pt 3 can be referred to Figure 1 . The metal core of the cluster is a distorted cubic octahedron, in which the platinum atoms (Pt) are distributed on the periphery of the middle layer along the C 3 axis, achieving the precise doping of Pt atoms on the surface of the cluster.

[0104] Example 3​

[0105] Using the alloy nanocluster Cu prepared in Example 1 10 Pt 3 to perform the electrocatalytic hydrogen evolution reaction, the specific steps are as follows: In a conventional three-electrode cell, electrochemical tests are carried out at room temperature. The reference electrode uses a commercial RHE electrode, and the counter electrode uses a graphite rod. A glassy carbon rotating disk electrode (RDE) with an area of 0.196 cm 2 is used as the working electrode to characterize the electrochemical hydrogen evolution (HER) activity of different catalysts. Electrochemical experiments are carried out in an Ar-saturated 1 M KOH electrolyte. Linear voltammograms are measured at a rotation speed of 1600 rpm (RDE) and a scan rate of 10 mV / s.

[0106] The experimental results are as Figure 5 shown. The HER activity of Cu 10 Pt 3 was studied using linear sweep voltammetry (LSV) in 1 M KOH aqueous solution. Compared with the commercial Pt / C catalyst, Cu 10 Pt 3 showed a higher current density at a lower overpotential. Specifically, the onset overpotentials of Cu 10 Pt 3 and Pt / C were 27 mV and 54 mV, respectively. This result indicates that Cu 10 Pt 3 has better electrochemical hydrogen evolution (HER) activity than the commercial Pt / C catalyst.

[0107] In the description of this specification, the description referring to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0108] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. An alloy nanocluster, characterized in that: The molecular formula of the alloy nanocluster is [Cu 10 Pt3X5Y6]·Z, wherein X is an alkyne ligand, Y is a nitrogen phosphine ligand, and Z is an anion.

2. The alloy nanocluster according to claim 1, characterized in that: The alkyne ligand includes phenylacetylene; and / or, the nitrogen phosphine ligand comprises diphenyl-2-pyridylphosphine; and / or, the anion comprises F - , Cl - Br - , ClO 4- PF 6- 、OTF - , BF 4- , SbF 6- 、NO 3- 、CH3COO - CF3SO 3- 、CuCl2 - At least one of .

3. The alloy nanocluster according to claim 2, characterized in that: Platinum atoms are distributed on the surface of the alloy nanocluster structure.

4. A method for preparing the alloy nanoclusters according to any one of claims 1 to 3, characterized in that: include: Performing a first mixing process on the copper source, the alkyne ligand, and the first solvent to obtain a first solution; adding an alkaline solvent to the first solution to obtain a second solution; The second solution is spin-dried and washed to obtain a first solid; Performing a second mixing process on the first solid, the nitrogen phosphine ligand, and the second solvent to obtain a third solution; adding a platinum source to the third solution to obtain a fourth solution; The fourth solution is subjected to a third mixing treatment with a reducing solution to obtain a solution containing alloy nanoclusters.

5. The method according to claim 4, characterized in that Further including: The solution containing the alloy nanoclusters is subjected to precipitation, centrifugation and crystallization treatment to obtain crystals of the alloy nanoclusters.

6. The method according to claim 4, characterized in that The molar ratio of the copper source to the alkyne ligand is 1:(0.8-1.2); And / or, the copper source is selected from Cu(CH3CN)4Z1, wherein Z1 is an anion, and the anion includes F - , Cl - Br - , ClO 4- PF 6- 、OTF - , BF 4- , SbF 6- 、NO 3- 、CH3COO - CF3SO 3- At least one of; and / or, the alkyne ligand is selected from phenylacetylene; and / or, the molar concentration of the copper source in the first solution is 0.1-0.2 mmol / mL; And / or, the first solvent is selected from at least one of dichloromethane, chloroform, methanol, acetone, tetrahydrofuran and ethanol.

7. The method according to claim 4, characterized in that The molar ratio of the alkaline solvent to the copper source is 1:(0.5-2); And / or, the alkaline solvent is selected from triethylamine; And / or, the washing treatment is carried out using at least one of n-hexane, ethanol and ether.

8. The method according to claim 4, characterized in that The molar ratio of the first solid to the nitrogen phosphine ligand is 1:(0.3-0.8); and / or, the nitrogen phosphine ligand is selected from diphenyl-2-pyridylphosphine; and / or, the molar concentration of the first solid in the third solution is 0.01-0.05 mmol / mL; and / or, the concentration of the platinum source in the fourth solution is 0.001-0.004 mmol / mL; and / or, the second solvent is selected from toluene and benzene; And / or, the platinum source is selected from potassium chloroplatinate and sodium chloroplatinate; And / or, the reducing solution is selected from an ethanol solution or a methanol solution containing sodium borohydride.

9. The method according to claim 5, characterized in that The precipitation is carried out using at least one of n-hexane, n-pentane, petroleum ether and n-heptane; And / or, the crystallization treatment includes: adding a good solvent to the centrifuged product, and covering a poor solvent on the upper layer of the centrifuged product, so as to precipitate crystals of the alloy nanoclusters by diffusion.

10. Use of the alloy nanocluster according to any one of claims 1 to 3 or the alloy nanocluster prepared by the method according to any one of claims 4 to 9 in electrocatalytic hydrogen evolution.

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