MoSxTe2-x two-dimensional alloy anti-adsorption defect regulation and control method and application

Abstract

The invention belongs to the field of two-dimensional material defect regulation and control, and discloses a regulation and control method for two-dimensional alloy anti-position adsorption defects. The regulation and control method comprises the steps that tellurium serves as a tellurium source and is placed at the gas inlet end of a quartz tube; placing the substrate spin-coated with the sodium molybdate solution and a target substrate face to face to form a space confinement reaction cavity, placing the space confinement reaction cavity at a gas outlet end, introducing Ar / H2 carrier gas, and enabling the space confinement reaction cavity to react with a tellurium source for 10-25 minutes to obtain a thin layer MoTe2; the preparation method comprises the following steps: taking sulfur powder as a sulfur source, placing the sulfur source at a gas inlet end of a quartz tube, placing MoTe2 at a gas outlet end, introducing inert carrier gas, respectively heating a high-temperature region and a low-temperature region of the quartz tube to 250-450 DEG C and 160-180 DEG C, and reacting the thin layer MoTe2 with the sulfur source for 5-10 minutes to obtain the MoSxTe2-x two-dimensional alloy with the anti-adsorption defect. Based on the chemical activity difference of sulfur / tellurium atoms, in the reaction process of sulfur and MoTe2, the atom rearrangement mechanism promotes the tellurium atoms to be adsorbed to the top of the Mo site, so that the structural integrity of the material is kept under the mild reaction condition, and the method has the advantages of low energy consumption, simplicity and convenience in operation and high controllability.

Description

Technical Field

[0001] The present invention belongs to the field of two-dimensional material defect regulation, and specifically relates to a method for regulating MoS x Te 2-x antisite adsorption defects in two-dimensional alloys and its application. Background Art

[0002] Two-dimensional transition metal dichalcogenides (TMDCs) have shown important application values in the field of electrocatalytic hydrogen evolution due to their advantages such as good cost-effectiveness, tunable bandgap structure, and high specific surface area. In order to improve the catalytic activity of the basal plane of two-dimensional TMDCs, extensive research has been carried out on the defect engineering of TMDCs and their alloys. Currently, the commonly used defect preparation strategies for two-dimensional TMDCs and their alloys include: ball milling, plasma etching, chemical reduction, and chemical vapor deposition (CVD). The ball milling method, with the advantages of simple process and easy scale-up, can control the defect density by adjusting the ball milling time or solvent type, but has the problem of high energy consumption; the plasma etching method uses high-energy gas to precisely control the defect density, but may damage the intrinsic structure of the material; the chemical reduction strategy realizes defect construction through reducing agents, but the controllability of defect characteristics is limited by a narrow process parameter window; CVD, as one of the mainstream technologies for preparing high-quality two-dimensional TMDCs and their alloys, can combine heteroatom doping to realize defect design, but puts forward strict requirements for the precise coordinated control of multiple parameters such as precursor ratio, temperature, and carrier gas. Two-dimensional MoS x Te 2-x As a typical ternary alloy system, previous studies mostly used a CVD system to perform tellurization treatment on the MoS2 precursor to introduce Te vacancies, but this method has significant limitations: on the one hand, because the chemical activity of Te is lower than that of S, it is necessary to rely on reducing gas (H2) and high-temperature environment (~700 °C) to drive the alloying reaction, which easily causes irreversible damage to the layered structure of the MoS2 precursor; on the other hand, the harsh reaction conditions (dependency on temperature and carrier gas) severely limit the regulation window of defect density and type, and it is difficult to achieve large-area defect construction and precise design of new defect configurations. These bottlenecks make the hydrogen evolution performance improvement of two-dimensional MoS x Te 2-x alloy materials limited. Therefore, realizing the controllable preparation of defects in two-dimensional MoS x Te 2-x alloys and constructing new and efficient hydrogen evolution defect configurations are of great significance for improving electrocatalytic hydrogen evolution performance. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the above-mentioned deficiencies and defects in the background art, and provide a MoS x Te 2-xMethod and application for regulating anti-site adsorption defects in two-dimensional alloys. Based on the mechanism of chemical replacement reaction, the present invention realizes the dissociation and reconstruction of Te atoms from lattice sites during the atomic rearrangement kinetic process by constructing a two-temperature-region chemical equilibrium system, and finally forms anti-site adsorption defects. Compared with traditional physical defect regulation strategies, this method is more simple and mild, can accurately and efficiently construct new defects, and avoid damaging the structure of two-dimensional materials.

[0004] To solve the above technical problems, the technical solution proposed by the present invention is as follows: A kind of MoS x Te 2-x Method for regulating anti-site adsorption defects in two-dimensional alloy, comprising the following steps: (1) Take tellurium powder as the tellurium source and place it at the inlet end of the quartz tube of the two-temperature-region tube furnace; Place the substrate spin-coated with sodium molybdate solution and another target substrate face to face to form a spatially confined reaction cavity, and place it at the outlet end of the quartz tube; Seal the quartz tube, introduce Ar / H2 carrier gas, heat the high-temperature region and low-temperature region of the quartz tube to 600-750 °C and 480-550 °C respectively, adjust the relative position of the quartz tube and the furnace body, and make the spatially confined reaction cavity react with the tellurium source for 10-25 min; After the reaction is completed, introduce inert carrier gas, cool the quartz tube to room temperature in an inert atmosphere, take out the spatially confined reaction cavity, and obtain a thin layer of MoTe2 on the surface of the target substrate; (2) Take sulfur powder as the sulfur source and place it at the inlet end of the quartz tube of the two-temperature-region tube furnace; Place the MoTe2 obtained in step (1) at the outlet end of the quartz tube and seal the quartz tube; Introduce inert carrier gas, and heat the high-temperature region and low-temperature region of the quartz tube to 250-450 °C and 160-180 °C respectively, adjust the relative position of the quartz tube and the furnace body, and make the thin layer of MoTe2 react with the sulfur source for 5-10 min; After the reaction is completed, adjust the flow rate of the inert carrier gas, cool the quartz tube to room temperature in an inert atmosphere, take out the target substrate, and obtain MoS x Te 2-x Two-dimensional alloy with anti-site adsorption defects.

[0005] For the above regulation method, preferably, in step (1), the flow rate of the Ar / H2 carrier gas is 60-100 sccm, and the volume ratio of Ar to H2 in the Ar / H2 carrier gas is 9:1.

[0006] For the above regulation method, preferably, in step (2), the introduction of inert carrier gas means introducing argon, and the argon flow rate is 60-100 sccm.

[0007] For the above-mentioned regulation method, preferably, in steps (1) and (2), the inert carrier gas introduced after the reaction ends is argon, and the flow rate is 150 - 180 sccm.

[0008] For the above-mentioned regulation method, preferably, in step (1), both the substrate for spin-coating the sodium molybdate solution and the target substrate are silicon wafers.

[0009] For the above-mentioned regulation method, preferably, in step (1), before spin-coating the sodium molybdate solution, the surface of the substrate for spin-coating the sodium molybdate solution is modified by oxygen plasma with a power of 50 W for 30 seconds; the concentration of the sodium molybdate solution used for spin-coating is 0.025 - 0.1 mol / L; the spin-coating means measuring 80 μL of the solution with a pipette and dropping it onto the surface of the modified substrate, and controlling the rotation speed of the spin coater to be 1000 - 4000 rpm, and the spin-coating time to be 10 - 60 s.

[0010] For the above-mentioned regulation method, preferably, in step (1), the thickness of the thin layer of MoTe2 is 0.9 - 5 nm.

[0011] For the above-mentioned regulation method, preferably, in step (2), the thickness of the MoS x Te 2-x two-dimensional alloy with anti-site adsorption defects obtained on the surface of the target substrate is 0.9 - 5 nm.

[0012] For the above-mentioned regulation method, preferably, in the MoS x Te 2-x alloy, the point defect where Te atoms are adsorbed on the top of Mo sites.

[0013] For the above-mentioned regulation method, preferably, in step (1), after the high-temperature zone and the low-temperature zone of the quartz tube both reach the preset temperature, adjust the relative position of the quartz tube and the furnace body so that the spatial confinement reaction chamber is aligned with the center of the high-temperature zone of the quartz tube, and at the same time align the tellurium source with the center of the low-temperature zone of the quartz tube.

[0014] For the above-mentioned regulation method, preferably, in step (2), after the high-temperature zone and the low-temperature zone of the quartz tube both reach the preset temperature, adjust the relative position of the quartz tube and the furnace body so that the target substrate loaded with MoTe2 is aligned with the center of the high-temperature zone of the quartz tube, and at the same time align the sulfur source with the center of the low-temperature zone of the quartz tube.

[0015] Compared with the prior art, the beneficial effects of the present invention are: (1) Based on the chemical activity difference between sulfur / tellurium atoms, during the reaction of highly active sulfur with MoTe2, the atomic rearrangement mechanism promotes the adsorption of tellurium atoms on top of the Mo sites, thereby maintaining the structural integrity of the material under mild reaction conditions (i.e., lower temperature of 250 - 450 °C and inert atmosphere environment), with the advantages of low energy consumption, simple operation, and strong controllability.

[0016] (2) The present invention provides a method for preparing anti-site adsorption defects on a large area of the MoS x Te 2-x two-dimensional alloy substrate, which can precisely control the defect density within the range of 0.19 - 0.32 nm -2 range. This method realizes the controllable construction of novel anti-site adsorption defects for the first time, endows the material with excellent electrocatalytic hydrogen evolution performance, and shows broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] Figure 1 It is a schematic diagram of the double-temperature zone tube furnace and its quartz tube structure used in the regulation process of anti-site adsorption defects of the MoS x Te 2-x two-dimensional alloy in Example 1 of the present invention: a corresponds to the preparation of MoTe2 in step (1); b corresponds to the preparation of MoS x Te 2-x two-dimensional alloy; Figure 2 It is a physical diagram of the double-temperature zone tube furnace and its quartz tube structure used in the regulation process of anti-site adsorption defects of the MoS x Te 2-x two-dimensional alloy in Example 1 of the present invention: a corresponds to the preparation of MoTe2 in step (1); b corresponds to the preparation of MoS x Te 2-x two-dimensional alloy; Figure 3 It is the optical micrograph and Raman spectrum of the two-dimensional MoTe2 and MoS x Te 2-x two-dimensional alloy prepared in Example 1 of the present invention: a corresponds to the optical micrograph of two-dimensional MoTe2; b corresponds to the optical micrograph of MoS x Te 2-x two-dimensional alloy; c corresponds to the optical micrograph of two-dimensional MoTe2 and MoS x Te2-x Raman spectra of two-dimensional alloys

[0019] Figure 4 are the two-dimensional MoTe2 and MoS prepared in Example 1 of the present invention x Te 2-x Atomic force microscopy images of two-dimensional alloys: a corresponds to two-dimensional MoTe2; b corresponds to MoS x Te 2-x 。

[0020] Figure 5 are the optical microscopy images and Raman spectra of two-dimensional MoTe2 prepared in Examples 2-6 of the present invention: a corresponds to Example 2; b corresponds to Example 3; c corresponds to Example 4; d corresponds to Example 5; e corresponds to Example 6; f corresponds to the Raman spectrum of MoTe2 prepared in Examples 2-6

[0021] Figure 6 is the MoS prepared in Example 1 of the present invention x Te 2-x Analysis of atomic-level defect structure of two-dimensional alloys: a is MoS x Te 2-x Scanning transmission electron microscopy images of two-dimensional alloys; b is the scanning transmission electron microscopy image simulated based on the structural model of Te atoms adsorbed on the top of Mo sites; c is the scanning transmission electron microscopy image simulated based on the structural model of Te atoms substituting Mo sites; d is the atomic contrast profile line of the red bracket area in Figures a-c

[0022] Figure 7 are the MoS with anti-site adsorption defects prepared in Examples 1 and 7-11 of the present invention x Te 2-x Scanning transmission electron microscopy images of two-dimensional alloys: a corresponds to Example 1; b corresponds to Example 7; c corresponds to Example 8; d corresponds to Example 9; e corresponds to Example 10; f corresponds to Example 11

[0023] Figure 8 are the MoS with anti-site adsorption defects prepared in Examples 1, 7, 8 and 11 of the present invention x Te 2-x Analysis of electrocatalytic hydrogen evolution performance of two-dimensional alloys: a is the linear sweep voltammogram; b is the Tafel curve Detailed implementation manners

[0024] For the convenience of understanding the present invention, the present invention will be described more comprehensively and meticulously below in conjunction with the accompanying drawings of the specification and preferred embodiments, but the protection scope of the present invention is not limited to the following specific embodiments

[0025] Unless otherwise defined, all technical terms used hereinafter have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention.

[0026] Unless otherwise specifically stated, various raw materials, reagents, instruments, and equipment used in the present invention can be obtained through market purchase or can be prepared by existing methods.

[0027] Example 1: A method for regulating MoS x Te 2-x antisite adsorption defects in two-dimensional alloys, the schematic structural diagram of the two-temperature zone tube furnace and its quartz tube used is as Figure 1 shown, and the specific equipment is as Figure 2 shown, including the following steps: S1: Use silicon wafers of 15 mm×15 mm×0.5 mm as the spin-coating substrate and the target substrate respectively. Place the spin-coating substrate in an oxygen plasma treatment device and treat it in an oxygen plasma environment at a power of 50 W for 30 s to facilitate subsequent loading of sodium molybdate solution; Fix the spin-coating substrate on a spin coater and apply negative pressure through a vacuum mechanical pump; use a pipette gun to take 80 μL of 0.025 mol / L sodium molybdate solution, drop it onto the center of the substrate, and perform spin coating. First, spin coat at 1000 rpm for 10 s, and then spin coat at 4000 rpm for 30 s. After completion, turn off the vacuum pump and take out the substrate loaded with sodium molybdate; Place the target substrate and the spin-coating substrate loaded with sodium molybdate with the target substrate facing up and the spin-coating substrate facing down, so that the polished surfaces are opposite to each other, thereby forming a spatially confined reaction cavity; Weigh 0.1 g of tellurium powder and place it in an aluminum foil boat as the tellurium source; in a 1-inch diameter quartz tube, mark the coincidence of the tube furnace insulation ring as 0 cm, place the tellurium source at 16.5 cm, which is close to the gas inlet end of the two-temperature zone tube furnace quartz tube; place the spatially confined reaction cavity at 39.5 cm, which is the gas outlet end of the quartz tube; install the inlet and outlet flange ends and ensure sealing, and introduce a 100 sccm Ar / H2 (volume ratio of Ar and H2 is 9:1) gas flow for 10 min to exhaust the air in the tube; Under a 100 sccm Ar / H2 gas flow, move the two-temperature zone tube furnace out of the reaction area, set the temperature of the low-temperature zone to 500 °C and the temperature of the high-temperature zone to 680 °C. When the temperature reaches the set value, the gas flow drops to 70 sccm, and then push the tube furnace back so that the tellurium source and the reaction cavity are respectively aligned with the centers of the low-temperature and high-temperature zones of the two-temperature zone tube furnace, and maintain the above set temperature and carrier gas parameters for 20 min; After the reaction is completed, stop introducing the Ar / H2 gas, change to introduce 160 sccm argon gas, and after 1 minute, remove the tube furnace and stop heating. After it cools down to room temperature, close the argon gas flow, take out the spatial reaction chamber, and obtain MoTe2 on the target substrate.

[0028] S2: Weigh 0.2 g of sulfur powder and place it in an aluminum foil boat as the sulfur source; inside a 1-inch diameter quartz tube, mark the overlapping part of the tube furnace insulation ring as 0 cm, place the sulfur source at 16.5 cm, and place the target substrate loaded with MoTe2 at 39.5 cm; Install the inlet and outlet flange at both ends of the quartz tube and ensure sealing. Introduce argon gas with a flow rate of 100 sccm for 10 minutes to expel the air inside the quartz tube; Under the argon gas flow rate of 100 sccm, move the tube furnace out of the reaction area, set the temperature of the low-temperature zone to 160 °C and the temperature of the high-temperature zone to 250 °C. When the temperature is stable, reduce the argon gas flow to 80 sccm, and push the tube furnace back so that the sulfur source and the target substrate are respectively aligned with the centers of the low- and high-temperature zones. Maintain the above set temperature and carrier gas parameters and react for 5 minutes; After the reaction is completed, adjust the argon gas flow rate to 160 sccm. After 1 minute, remove the tube furnace and stop heating. After it cools down to room temperature, close the argon gas flow, take out the target substrate, and obtain MoS x Te 2-x Two-dimensional alloy.

[0029] In this example, the MoTe2 prepared in step (1) and the MoS x Te 2-x The optical microscope images and Raman spectroscopy results of are as Figure 3 shown, and the atomic force microscopy images are as Figure 4 shown. MoS x Te 2-x is similar in morphology to the MoTe2 precursor, and the thickness is in the range of 0.9 - 1 nm. Raman spectroscopy proves that the samples prepared from the two are MoTe2 and MoS x Te 2-x .

[0030] Furthermore, the electrocatalytic hydrogen evolution performance of the sample was tested. The overpotential at a current density of 10 mA·cm -2 is 238 mV, and the Tafel slope is 89 mV·dec -1 .

[0031] Examples 2 - 6: Examples 2-6 are different from Example 1 only in that in step (1), different growth temperatures, sodium molybdate solution concentrations, gas flow rates, and reaction times are used to prepare MoTe2, and other implementation processes and parameters are the same as those in Example 1, as specifically shown in Table 1.

[0032] Table 1 Main parameters for preparing MoTe2 in Examples 1-6

[0033] The optical microscope images of MoTe2 prepared in step (1) in Examples 2-6 are as Figure 5 shown in a-e, revealing that the MoTe2 precursors all exhibit a thin-layer long-strip morphology on the substrate surface.

[0034] By systematically analyzing the Raman spectral characteristics ( Figure 5 f) under different growth conditions, the characteristic vibration modes (such as A g , B g , etc.) of all samples are in good agreement with the reported Raman data of two-dimensional MoTe2, confirming the chemical purity of the products. The experimental data show that two-dimensional MoTe2 has a relatively wide growth window.

[0035] Examples 7-11: Examples 7-11 are different from Example 1 only in that in step (2), different growth temperatures, gas flow rates, and reaction times are used to prepare MoS x Te 2-x , and other implementation processes are the same as those in Example 1, as specifically shown in Table 2.

[0036] Table 2 Main parameters for preparing MoS x Te 2-x

[0037] As Figure 6 shown, based on the MoS x Te 2-x two-dimensional alloy prepared in Example 1, the atomic-level defect structure was identified and analyzed. By comparing the contrast profiles of the STEM images obtained from simulation and experiment, it was found that the experimental data highly match the contrast distribution of the image simulated based on the structure of Te atoms adsorbed on the top of Mo sites, thus confirming that these anti-site Te atoms are adsorbed on Mo sites rather than substituting Mo atoms.

[0038] The scanning transmission electron microscope images of the MoS x Te 2-x two-dimensional alloy with anti-site adsorption defects prepared in Examples 1 and 7-11 are shown in Figure 7 , and their anti-site adsorption defect densities are 0.34 nm-2 , 0.27 nm -2 , 0.19 nm -2 , 0.20 nm -2 , 0.22 nm -2 and 0.26 nm -2 . It can be seen from Figure 7 that by adjusting the temperatures of the two temperature zones, the gas flow rate, and the reaction time, the present invention can precisely control the density of anti-site adsorption defects in the MoS x Te 2-x alloy. At moderate low-temperature zone temperatures, gas flow rates, and reaction times, as the temperature of the high-temperature zone increases, the density of anti-site adsorption defects gradually decreases. This may be because at lower temperatures, anti-site adsorption defects are easily retained, while a higher reaction temperature promotes the lattice dynamic reconstruction in the MoS x Te 2-x two-dimensional alloy, but is not conducive to the maintenance of this metastable defect, thus reducing the tendency of Te atoms to anti-site adsorb on Mo thermodynamically. Prolonging the reaction time will reduce the density of anti-site adsorption defects, demonstrating that over-sulfidation of MoTe2 may inhibit the formation of this defect.

[0039] Examples 7, 8, and 11 also confirm the regulatory effect of the high-temperature center temperature and the reaction time on the density of anti-site adsorption defects in MoS x Te 2-x and its electrocatalytic hydrogen evolution performance. As Figure 8 shown, the overpotential of the sample of Example 7 at a current density of 10 mA·cm -2 is 256 mV, and the Tafel slope is 125 mV·dec -1 . The overpotential of the sample of Example 8 at a current density of 10 mA·cm -2 is 394 mV, and the Tafel slope is 151 mV·dec -1 . The overpotential of the sample of Example 11 at a current density of 10 mA·cm -2 is 259 mV, and the Tafel slope is 138 mV·dec -1 .

[0040] Thus, it can be seen that when only changing the high-temperature center temperature, the density of anti-site adsorption defects in the prepared MoS x Te 2-x increases as the temperature decreases, and the electrocatalytic hydrogen evolution performance improves (both the overpotential and the Tafel slope decrease at a current density of 10 mA·cm -2 ). When only changing the reaction time, the density of anti-site adsorption defects in the prepared MoS x Te 2-xThe density of anti-site adsorption defects decreases with the prolongation of the reaction time, and the electrocatalytic hydrogen evolution performance deteriorates. Therefore, increasing the density of anti-site adsorption defects is beneficial to improving the electrocatalytic performance.

[0041] The above-described embodiments are all technical solutions of the present invention, but are not limited to the above embodiments, and there are still many variations and improvements. Any changes or deformations that can be made by those skilled in the art based on the disclosed content of the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for regulating MoS x Te 2-x two-dimensional alloy anti-site adsorption defects, characterized in that, It includes the following steps: (1) Use tellurium powder as the tellurium source and place it at the gas inlet end of the quartz tube in a two-temperature-zone tube furnace; Place the substrate spin-coated with sodium molybdate solution and the target substrate face to face to form a spatially confined reaction chamber, and place it at the gas outlet end of the quartz tube; Seal the quartz tube, introduce Ar / H2 carrier gas, heat the high-temperature zone and the low-temperature zone of the quartz tube to 600 - 750 °C and 480 - 550 °C respectively, adjust the relative position of the quartz tube and the furnace body, and make the spatially confined reaction chamber react with the tellurium source for 10 - 25 min; After the reaction ends, introduce an inert carrier gas, cool the quartz tube to room temperature in an inert atmosphere, take out the spatially confined reaction chamber, and obtain a thin layer of MoTe2 on the surface of the target substrate; (2) Use sulfur powder as the sulfur source and place it at the gas inlet end of the quartz tube in a two-temperature-zone tube furnace; Place the MoTe2 obtained in step (1) at the gas outlet end of the quartz tube and seal the quartz tube; Introduce an inert carrier gas, and heat the high-temperature zone and the low-temperature zone of the quartz tube to 250 - 450 °C and 160 - 180 °C respectively, adjust the relative position of the quartz tube and the furnace body, and make the thin layer of MoTe2 react with the sulfur source for 5 - 10 min; After the reaction is completed, adjust the flow rate of the inert carrier gas, cool the quartz tube to room temperature in an inert atmosphere, take out the target substrate, and obtain a MoS with anti-site adsorption defects x Te 2-x two-dimensional alloy.

2. The regulation method according to claim 1, characterized in that In step (1), the flow rate of the Ar / H2 carrier gas is 60 - 100 sccm, and the volume ratio of Ar to H2 in the Ar / H2 carrier gas is 9:

1.

3. The regulation method according to claim 1, characterized in that In step (2), introducing an inert carrier gas means introducing argon, and the flow rate of argon is 60 - 100 sccm.

4. The regulation method according to claim 1, characterized in that, In steps (1) and (2), the inert carrier gas introduced after the reaction ends is argon, and the flow rate is 150 - 180 sccm.

5. The regulation method according to claim 1, characterized in that, In step (1), both the substrate spin-coated with sodium molybdate solution and the target substrate are silicon wafers.

6. The regulation method according to claim 5, wherein, In step (1), before spin-coating the sodium molybdate solution, the surface of the substrate is modified by oxygen plasma with a power of 50 W for 30 seconds; The concentration of the sodium molybdate solution used for spin-coating is 0.025 - 0.1 mol / L; spin-coating means measuring 80 μL of the solution with a pipette and dropping it onto the surface of the modified substrate, and controlling the rotation speed of the spin coater to be 1000 - 4000 rpm, and the spin-coating time to be 10 - 60 s.

7. The regulation method according to claim 1, characterized in that In step (1), the thickness of the thin layer of MoTe2 is 0.9 - 5 nm.

8. The regulation method according to claim 1, characterized in that In step (2), MoS with anti-site adsorption defects obtained on the surface of the target substrate x Te 2-x The thickness of the two-dimensional alloy is 0.9 to 5 nm.

9. The regulation method according to any one of claims 1 to 8, characterized in that, The anti-site adsorption defect refers to the point defect where Te atoms in the MoS x Te 2-x alloy are adsorbed on the top of Mo sites.

10. Application of a two-dimensional alloy with anti-site adsorption defects MoS x Te 2-x obtained by the regulation method according to any one of claims 1 to 9 in electrocatalytic hydrogen evolution. x Te 2-x ​

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