Pt-based nanomaterial, and preparation method and application thereof

Abstract

The application relates to a Pt-based nanomaterial and a preparation method and application thereof, and belongs to the technical field of nanomaterials. The Pt-based nanomaterial provided by the application is a nanomaterial with a Pt-PtTe2 heterojunction or a Te-PtTe2 heterojunction, or a single-phase PtTe2 nanomaterial, wherein the molar ratio of Pt and Te elements meets a certain condition. The application can continuously control the ratio of raw materials, so that the Pt-based nanomaterial has a heterojunction structure based on PtTe2, and the types and preparation methods of topological semimetal van der Waals heterojunctions are enriched. The Pt-based nanomaterial provided by the application can exert the catalytic effect of oxidase and catalase, catalyze the reaction of hydrogen peroxide and other substances, and degrade, and has high application value in the fields of catalytic degradation, biological medicine and the like.

Description

Technical Field

[0001] This invention relates to the field of nanomaterials technology, and in particular to a Pt-based nanomaterial, its preparation method, and its application. Background Technology

[0002] A heterojunction is a structure composed of two different materials with different electron affinities. Therefore, the band structure formed by a heterojunction will change, resulting in band shifts and electron transfer, which can promote the transfer and separation of electron-hole pairs. - -h + The effective separation of reactive oxygen species determines the quantum yield of reactive oxygen species. Meanwhile, the different chemical compositions and lattice structures in heterostructures induce lattice strains such as stretching and compression, affecting the adsorption energy of intermediates at the sites and enhancing the catalytic activity of the material.

[0003] PtTe2 is a group 10 noble metal telluride, belonging to topological half-metals. It exhibits type II Diclavone fermion properties and has a trigonal CdⅠ2-type crystal structure with space group P-3m1, a typical 1T phase lattice structure. As a two-dimensional Diclavone half-metal material, PtTe2 possesses tilted type II Diclavone cones, exhibiting high carrier mobility and achieving ultra-high electrical conductivity, making it valuable for applications in electrodes and catalytic reactions. However, research on the preparation of PtTe2-based heterojunctions and their catalytic performance is relatively scarce.

[0004] Therefore, developing a PtTe2-based nanomaterial with a heterostructure and its preparation method is of great research and application value, as it can further enhance the catalytic activity of the material and broaden its application range. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a Pt-based nanomaterial, its preparation method, and its applications. The Pt-based nanomaterial provided by this invention can act as an enzyme to catalyze the reaction and degradation of hydrogen peroxide, exhibiting excellent catalytic effects and high application value in the fields of catalytic degradation and biomedicine.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] In a first aspect, the present invention provides a Pt-based nanomaterial, wherein the Pt-based nanomaterial is a nanomaterial having a Pt-PtTe2 heterostructure or a Te-PtTe2 heterostructure; or the Pt-based nanomaterial is a PtTe2 nanomaterial; wherein the molar ratio of Pt to Te in the Pt-based nanomaterial is 1:(0.45-3).

[0008] Within the molar ratio range of Pt to Te defined in this invention, by adjusting the ratio of Pt and Te, four different Pt-based nanomaterials with the following structures can be obtained: (1) a material with a Pt-PtTe2 heterostructure; (2) a material with a PtTe2-Ⅰ crystal form; (3) a material with a PtTe2-Ⅱ crystal form; and (4) a material with a Te-PtTe2 heterostructure. If the amount of Te is too low, too few PtTe2 frameworks will be formed, resulting in low yield and low raw material utilization. If the amount of Te is too high, the material cannot form a heterostructure or a single PtTe2 structure, and its effective components and uses cannot be determined.

[0009] The Pt-based nanomaterials prepared by the above method can act as oxidases or catalases, catalyzing the reaction and degradation of substances such as hydrogen peroxide, thereby converting toxic substances into non-toxic substances, and playing an important role in catalytic degradation and biomedical fields.

[0010] Preferably, in the Pt-based nanomaterial, the molar ratio of Pt to Te is 1:(0.45-0.92); or the molar ratio of Pt to Te is 1:(2.5-3).

[0011] When the molar ratio of Pt to Te is 1:(0.45-0.92), the prepared Pt-based nanomaterials have a Pt-PtTe2 heterojunction structure; when the molar ratio of Pt to Te is 1:(2.5-3), the prepared Pt-based nanomaterials have a Te-PtTe2 heterojunction structure; however, when the molar ratio of Pt to Te in the raw materials is within the above range, the prepared material is PtTe2 without a heterojunction, and the crystal structure is type I or type II. Since different chemical compositions and crystal structures in the heterojunction structure can cause lattice strains such as stretching and compression, affecting the adsorption energy of intermediates at the sites, compared with single PtTe2, the formed Pt-PtTe2 or Te-PtTe2 heterojunctions can significantly enhance the catalytic activity of nanomaterials as oxidases or catalases.

[0012] Preferably, the Pt-based nanomaterial is a rod-shaped nanomaterial with a particle size of 150-200 nm.

[0013] Secondly, the present invention provides a method for preparing the above-mentioned Pt-based nanomaterials, comprising the following steps:

[0014] The raw materials, polymer modifiers, and reducing agents are dissolved and mixed in a solvent, and then subjected to a hydrothermal reaction to obtain the Pt-based nanomaterials; the raw materials include Pt source and Te source.

[0015] This invention employs a hydrothermal reaction method to prepare Pt-based nanomaterials. The steps are simple, controllable, and pollution-free. Furthermore, the one-step synthesis is easy to operate. After the hydrothermal reaction, centrifugation yields the solid Pt-based nanomaterials. The materials use the two-dimensional Diclave semimetal PtTe2 as a framework. By controlling the molar ratio of the Pt source to the Te source, in-situ growth can be achieved on the PtTe2 framework, resulting in topological semimetal van der Waals heterojunctions Pt-PtTe2 and Te-PtTe2, which comprehensively enhance their catalytic performance.

[0016] Preferably, the solvent is a water / ethylene glycol mixed solution.

[0017] Preferably, the polymeric modifier is polyvinylpyrrolidone, and the reducing agent is L-ascorbic acid.

[0018] Preferably, the Pt source is [Pt(NH3)4](NO3)2, and the Te source is K2TeO3.

[0019] More preferably, the mass ratio of the preparation raw materials, polymeric modifier and reducing agent is preparation raw materials: polymeric modifier: reducing agent = (1.3-3): (9-11): (3.3-3.9).

[0020] The components can dissolve well in the above solvent and undergo further hydrothermal reaction. Under the above ratio, L-ascorbic acid is used as a reducing agent to cause redox reaction between Pt source and Te source, forming Pt-based nanomaterials with specific structures. Using polyvinylpyrrolidone in a specific ratio as a modifier for nanomaterials can maintain their dispersion stability and have good biocompatibility. At the same time, under the above conditions, the nanomaterials prepared are rod-shaped.

[0021] Preferably, the dissolving and mixing step specifically involves sonication for 20-30 minutes.

[0022] Preferably, the hydrothermal reaction is carried out at a temperature of 190-210°C for 4.5-5.5 hours.

[0023] Thirdly, this invention provides the application of the above-mentioned Pt-based nanomaterials in catalytic degradation and biomedicine.

[0024] Preferably, the application of the Pt-based nanomaterials in catalytic degradation is specifically as an oxidase or catalase in catalytic degradation. The aforementioned Pt-based nanomaterials are PtTe2 nanomaterials or nanomaterials with Pt-PtTe2 or Te-PtTe2 heterostructures, exhibiting strong catalytic activity and effectively performing the catalytic function of oxidases or catalases, thus finding applications in catalytic degradation, biomedicine, and other fields.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] This invention directly synthesizes Pt-based nanomaterials in one step via a hydrothermal method. The preparation method is simple and pollution-free. By continuously controlling the ratio of Pt and Te in the material, Pt-based nanomaterials with Pt-PtTe2 heterostructures, single PtTe2 structures, and Te-PtTe2 heterostructures can be obtained, enriching the types and preparation methods of topological half-metal van der Waals heterostructures. Furthermore, these nanomaterials can exert the catalytic effects of oxidase and catalase to catalyze the reaction and degradation of substances such as hydrogen peroxide, and have high application value in catalytic degradation, biomedicine, and other fields. Attached Figure Description

[0027] Figure 1 The image shows the XRD pattern of the Pt-based nanomaterial in Example 1.

[0028] Figure 2 TEM image of the Pt-based nanomaterial in Example 1;

[0029] Figure 3 The image shows the XRD pattern of the Pt-based nanomaterial in Example 2.

[0030] Figure 4 TEM image of the Pt-based nanomaterial in Example 2;

[0031] Figure 5 The image shows the XRD pattern of the Pt-based nanomaterial in Example 3.

[0032] Figure 6 TEM image of the Pt-based nanomaterial in Example 3;

[0033] Figure 7 The image shows the XRD pattern of the Pt-based nanomaterial in Example 4.

[0034] Figure 8 TEM image of the Pt-based nanomaterial in Example 4;

[0035] Figure 9 The XRD pattern of the material in Comparative Example 1;

[0036] Figure 10 The figure shows the experimental results of oxidase catalysis using Pt-PtTe2 heterostructure nanomaterials.

[0037] Figure 11 Figure 1 shows the experimental results of oxidase catalysis of PtTe2 nanomaterials;

[0038] Figure 12 The figure shows the experimental results of catalase catalysis using Pt-PtTe2 heterojunction nanomaterials.

[0039] Figure 13The figure shows the experimental results of catalase catalysis of PtTe2 nanomaterials. Detailed Implementation

[0040] To better illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments. Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods; the materials and reagents used, unless otherwise specified, are commercially available reagents and materials.

[0041] Example 1

[0042] This invention provides an embodiment of a method for preparing Pt-based nanomaterials. The method for preparing Pt-based nanomaterials according to this embodiment includes the following steps:

[0043] (1) Accurately weigh 10 mg [Pt(NH3)4](NO3)2, 6 mg K2TeO3, 100 mg polyvinylpyrrolidone and 36 mg L-ascorbic acid, mix them in water / ethylene glycol solution (molar ratio of Pt to Te is 1:0.92), and then sonicate for 25 min to dissolve them completely to obtain a mixed solution;

[0044] (2) The mixed solution obtained in step (1) is placed into a reaction vessel, kept at 200°C for 5 hours, cooled and centrifuged to obtain Pt-based nanomaterials.

[0045] The prepared Pt-based nanomaterials were analyzed by XRD and TEM.

[0046] The XRD pattern of the prepared Pt-based nanomaterials is shown in the figure. Figure 1 As shown: by Figure 1 It can be seen that the material is composed of two phases, Pt and PtTe2, indicating that the Pt-based nanomaterial has a Pt-PtTe2 heterostructure.

[0047] TEM images of the prepared Pt-based nanomaterials are shown below. Figure 2 As shown: Observing the microstructure and size, the material has a uniform rod-like structure with a size of 150-200 nm.

[0048] Example 2

[0049] The only difference between Example 2 and Example 1 is that the amount of K2TeO3 used is 12mg, and the molar ratio of Pt to Te is 1:1.8.

[0050] The prepared Pt-based nanomaterials were analyzed by XRD and TEM.

[0051] The XRD pattern of the prepared Pt-based nanomaterials is shown in the figure. Figure 3 As shown: by Figure 3It can be seen that the material is composed of a single phase of PtTe2-Ⅰ, forming PtTe2 nanomaterials;

[0052] TEM images of the prepared Pt-based nanomaterials are shown below. Figure 4 As shown: Observing the microstructure and size, the material has a uniform rod-like structure with a size of 150-200 nm.

[0053] Example 3

[0054] The only difference between Example 3 and Example 1 is that the amount of K2TeO3 used is 15mg, and the molar ratio of Pt to Te is 1:2.29.

[0055] The prepared Pt-based nanomaterials were analyzed by XRD and TEM.

[0056] The XRD pattern of the prepared Pt-based nanomaterials is shown in the figure. Figure 5 As shown: by Figure 5 It can be seen that the material is composed of a single phase of PtTe2-Ⅱ, forming PtTe2 nanomaterials;

[0057] TEM images of the prepared Pt-based nanomaterials are shown below. Figure 6 As shown: Observing the microstructure and size, the material has a uniform rod-like structure with a size of 150-200 nm.

[0058] Example 4

[0059] The only difference between Example 4 and Example 1 is that the amount of K2TeO3 used is 20mg, and the molar ratio of Pt to Te is 1:3.

[0060] The prepared Pt-based nanomaterials were analyzed by XRD and TEM.

[0061] The XRD pattern of the prepared Pt-based nanomaterials is shown in the figure. Figure 7 As shown: by Figure 7 It can be seen that the material is composed of two phases, Te and PtTe2, indicating that the Pt-based nanomaterial has a Te-PtTe2 heterostructure.

[0062] TEM images of the prepared Pt-based nanomaterials are shown below. Figure 8 As shown: Observing the microstructure and size, the material has a uniform rod-like structure with a size of 150-200 nm.

[0063] Example 5

[0064] The only difference between Example 5 and Example 1 is that the amount of K2TeO3 used is 3 mg, and the molar ratio of Pt to Te is 1:0.458.

[0065] The prepared Pt-based nanomaterials consist of two phases, Pt and PtTe2, and have a Pt-PtTe2 heterostructure.

[0066] Example 6

[0067] The only difference between Example 6 and Example 1 is that the amount of K2TeO3 used is 16.4 mg, and the molar ratio of Pt to Te is 1:2.5.

[0068] The prepared Pt-based nanomaterials consist of two phases, Te and PtTe2, and have a Te-PtTe2 heterostructure.

[0069] Comparative Example 1

[0070] The only difference between Comparative Example 1 and Example 1 is that the amount of K2TeO3 used is 25 mg, and the molar ratio of Pt to Te is 1:3.8.

[0071] The prepared material was subjected to XRD analysis.

[0072] The XRD pattern of the prepared material is shown below. Figure 9 As shown: by Figure 9 It can be seen that the formation of a single PtTe2 phase or a heterojunction cannot be observed, and the XRD characteristics cannot correspond to the crystal phases of other Pt / Te compounds, so it cannot be observed that they have effective components.

[0073] Comparative Example 2

[0074] The only difference between Comparative Example 2 and Example 1 is that the amount of K2TeO3 used is 2 mg, and the molar ratio of Pt to Te is 1:0.3.

[0075] The amount of solid material obtained after cooling and centrifugation is too small, resulting in low yield.

[0076] Example 1

[0077] To investigate the catalytic performance of the Pt-based nanomaterials provided by this invention as oxidases, the Pt-based nanomaterials prepared in Examples 1 and 2 above were subjected to oxidase activity assays, as follows:

[0078] (1) Pt-based nanomaterials were dissolved in PBS solutions with different pH values ​​to obtain Pt-based nanomaterial solutions with a concentration of 50 μg / mL, and TMB solutions with a concentration of 10 mg / mL were prepared using DMSO as solvent.

[0079] (2) Take 3 mL of Pt-based nanomaterial solution, add 100 μL of TMB solution, react for 10 minutes, centrifuge, take the supernatant, and measure the ultraviolet absorption value at 650 nm.

[0080] Pt-based nanomaterials were used to catalyze the organic dye TMB. The absorbance at 650 nm was measured using a UV-Vis spectrometer to determine the enzyme activity of the reactants. The oxidase catalyzed the organic dye TMB to produce a stable blue compound; the deeper the blue color of the resulting compound, the stronger the catalytic activity.

[0081] The oxidase catalysis results of Pt-based nanomaterials in Examples 1 and 2 are as follows: Figure 10 and Figure 11 .contrast Figure 10 , 11 It can be seen that nanomaterials with Pt-PtTe2 heterojunctions exhibit higher absorbance values ​​when catalyzing the formation of blue compounds from TMB at different pH values; the catalytic activity of nanomaterials with Pt-PtTe2 heterojunctions is significantly higher than that of PtTe2 nanomaterials, which is attributed to the enhanced catalytic activity of the materials due to the presence of the heterojunction.

[0082] Example 2

[0083] To investigate the catalytic performance of the Pt-based nanomaterials provided by this invention as catalase, the Pt-based nanomaterials prepared in Examples 1 and 2 were reacted with hydrogen peroxide, and the oxygen content produced was measured. The steps are as follows:

[0084] A certain volume of hydrogen peroxide was added to a Pt-based nanomaterial solution with a concentration of 25 μg / mL, so that the concentrations of hydrogen peroxide were 0, 200, 400, and 600 μmol / L, respectively, and the oxygen content generated was recorded using a dissolved oxygen meter.

[0085] The higher the oxygen production capacity of a material, the better its catalytic activity.

[0086] The catalase catalytic results of Pt-based nanomaterials in Examples 1 and 2 are as follows: Figure 12 and Figure 13 .contrast Figure 12 , 13 It can be seen that nanomaterials with Pt-PtTe2 heterojunctions produce more oxygen from hydrogen peroxide under different pH conditions; nanomaterials with Pt-PtTe2 heterojunctions have higher catalytic activity than PtTe2 nanomaterials, which is due to the presence of heterojunctions enhancing the catalytic activity of the materials.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A Pt-based nanomaterial, characterized in that, The Pt-based nanomaterial is a nanomaterial with a Pt-PtTe2 heterostructure or a Te-PtTe2 heterostructure; In the Pt-based nanomaterials with the Pt-PtTe2 heterostructure, the molar ratio of Pt to Te is 1:(0.45-0.92); in the Pt-based nanomaterials with the Te-PtTe2 heterostructure, the molar ratio of Pt to Te is 1:(2.5-3). The preparation method of the Pt-based nanomaterial includes the following steps: The raw materials, polymer modifiers, and reducing agents are dissolved and mixed in a solvent, and then subjected to a hydrothermal reaction to obtain the Pt-based nanomaterials; the raw materials include Pt sources and Te sources. The polymeric modifier is polyvinylpyrrolidone, and the reducing agent is L-ascorbic acid; The Pt source is [Pt(NH3)4](NO3)2, and the Te source is K2TeO3; The mass ratio of the preparation raw materials, polymer modifiers and reducing agents is: preparation raw materials: polymer modifiers: reducing agents = (1.3-3): (9-11): (3.3-3.9).

2. The Pt-based nanomaterial according to claim 1, characterized in that, The Pt-based nanomaterial is a rod-shaped nanomaterial with a particle size of 150-200 nm.

3. The Pt-based nanomaterial according to claim 1, characterized in that, The hydrothermal reaction is carried out at a temperature of 190-210℃ for a time of 4.5-5.5 h.

4. The application of the Pt-based nanomaterials according to any one of claims 1-3 in catalytic degradation.

5. The application of the Pt-based nanomaterials according to claim 4 in catalytic degradation, characterized in that, The specific application of the Pt-based nanomaterials in catalytic degradation is as follows: they are used as oxidases or catalases in catalytic degradation.

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