Preparation method and application of high-curvature pdse nanoneedle catalyst

Abstract

The application discloses a preparation method and application of a high-curvature PdSe nanoneedle catalyst, and the preparation method of the high-curvature PdSe nanoneedle catalyst is as follows: taking a conductive material as a working electrode base, taking a platinum sheet as a counter electrode, adding a proper amount of Pd salt precursor in an acid aqueous solution, growing Pd components on the base by adopting a cyclic square wave electrodeposition method, the cyclic square wave electrodeposition method comprises the following steps: 1) setting a working electrode potential from 0.8 V to -0.7 V and applying multiple cycles; 2) setting a working electrode potential from 0.6 V to 0.25 V and applying multiple cycles, and then performing flushing and drying; then, the dried sample is selenized at high temperature in a tube furnace, and the high-curvature PdSe nanoneedle catalyst is obtained. The high-curvature PdSe nanocatalyst prepared by the cyclic square wave electrodeposition method is used as a cathode working electrode of an electrochemical reaction, and deuterium water is used as a deuterium source to realize efficient synthesis of alkynes to deuterated alkenes.

Description

Technical Field

[0001] The present invention belongs to the technical field of electrochemical catalyst material preparation, and in particular relates to a preparation method and application of a high-curvature PdSe nano-needle-tip catalyst. Background Art

[0002] Since the 2017 approval of deuterated tetrabenazine by the US Food and Drug Administration as the first deuterated drug for Huntington's disease, research focused on developing deuterated molecules has surged. This has led to a booming market for deuterium-labeled drugs. Among the vast array of deuterium-labeled functional groups, deuterium-labeled alkenes have emerged as a unique and prominent feature within the structural framework. They are not only widely used as starting materials for the construction of various deuterium-substituted target compounds, but also serve as valuable intermediates and end-products in numerous pharmaceuticals, pesticides, and natural products.

[0003] Hydrogen isotope exchange is generally a mainstream strategy for synthesizing deuterated compounds because it does not require prefunctionalization. However, it generally requires harsh reaction conditions (e.g., strong acids and bases, high temperature and pressure, and stoichiometric reducing agents), which makes it difficult to control the deuterium substitution site and amount, has poor functional group tolerance, and produces a large amount of chemical waste. In addition, the safety risks associated with the storage, transportation, and use of high-pressure and flammable D2 remain significant issues. In contrast, the reductive deuteration of unsaturated bonds (e.g., C≡C) with D2O provides a promising route for the unique installation of deuterium atoms in target molecules. Although many deuteration reactions involving D2O have emerged, they generally require complex ligands, homogeneous catalysts, or high temperatures, which hinder their practical application. Therefore, it is necessary to develop an efficient catalyst and a mild high-deuterium doping strategy, as well as a sustainable deuterium source.

[0004] In recent years, synthetic chemistry using sustainable electricity as an energy source has emerged as a powerful tool with green and efficient properties. Its highly tunable current and voltage characteristics have enabled it to excel in a wide range of reduction reactions, particularly in water electrolysis to generate reactive D(H) species and electrochemical deuteration (hydrogenation). In electrocatalytic water splitting, generating reactive D molecules by cleaving the O-D bond in D2O by electrolysis is considered a potential research avenue. Therefore, utilizing in situ generated reactive D to achieve highly controllable, site-selective production of deuterium-labeled alkenes is highly attractive. Summary of the Invention

[0005] The purpose of the present invention is to provide a preparation method and application of a high-curvature PdSe nanotip catalyst. The advantages of the preparation of the high-curvature PdSe nanotip catalyst of the present invention are mild reaction conditions and simple operation. By controlling the content of loaded metal Pd and using Se to regulate the distribution of Pd active sites, deuterated water is used as the deuterium source, and efficient synthesis of alkynes to deuterated alkenes is achieved over a wide potential range.

[0006] A method for preparing a high-curvature PdSe nano-needle-tip catalyst comprises the following steps:

[0007] In the first step, a conductive material is used as the cathode substrate of the working electrode, a platinum sheet is used as the anode counter electrode, a Pd precursor is dissolved in an acidic aqueous solution as the electrolyte, and a cyclic square wave electrodeposition method is used to grow the Pd component on the substrate. The cyclic square wave electrodeposition method includes the following two steps:

[0008] 1) Setting the working electrode potential from 0.8 V ± 0.05 V to -0.7 V ± 0.05 V and applying multiple cycles;

[0009] 2) Setting the working electrode potential from 0.6 V ± 0.05 V to 0.2 V ± 0.05 V for multiple cycles, followed by rinsing and drying;

[0010] In the second step, the sample dried in the first step is selenized at high temperature in a tube furnace to obtain the high-curvature PdSe nano-needle-tip catalyst.

[0011] Furthermore, the conductive material is one of carbon paper, carbon cloth, nickel foam and nickel mesh, and the acidic aqueous solution is a low-concentration sulfuric acid solution or a hydrochloric acid solution, and its concentration is 0.1-1M.

[0012] Furthermore, the Pd precursor is one of PdCl2, K2PdCl4, K2PdCl6, and Na2PdCl4, preferably K2PdCl6; the final concentration of the Pd precursor dissolved in the acidic aqueous solution is 1-10 mM.

[0013] Furthermore, in the cyclic square wave electrodeposition method, the number of cycles in step 1) is 500-3000 times, preferably 2000 times, and the step time of the two potentials is 0.01-0.1 seconds.

[0014] Furthermore, in the cyclic square wave electrodeposition method, the number of cycles in step 2) is 50,000-200,000 times, preferably 60,000 times, and the step time of the two potentials is 0.001-0.01 seconds.

[0015] Furthermore, the process in the high-temperature selenization step is: placing Se powder in the upstream of a tube furnace, placing the dried sample in the downstream of the tube furnace, and calcining under the condition of passing inert gas Ar or N2, and the calcination temperature is 200-600℃.

[0016] Furthermore, the calcination temperature is 300-400° C., and the molar ratio of Se powder to the Pd precursor in the first-step electrolyte is 25-75:1, preferably 40-50:1.

[0017] The present invention also provides an application of the high-curvature PdSe nano-needle tip catalyst in the electrocatalytic synthesis of deuterated olefins. The high-curvature PdSe nano-needle tip catalyst is used as a cathode working electrode in an electrochemical reaction to synthesize deuterated olefins using deuterated water as a deuterium source and alkynes as substrates.

[0018] Furthermore, the application uses an electrochemical workstation as an electrochemical generating device and a three-electrode flow electrolytic cell measurement system. The anode and cathode chambers of the electrolytic cell are separated by an anion exchange membrane, and the anode and cathode chambers are respectively transported by circulating pumps. The high-curvature Pd nano-needle tip catalyst is used as the cathode working electrode, a carbon rod is used as the counter electrode, mercury / mercuric oxide is used as the reference electrode, a tetrahydrofuran / deuterium water mixed solution with a volume ratio of 1:1 to 5 is used as the solvent, potassium carbonate is used as the solute, and a 0.1-1M K2CO3 solution is prepared as the electrolyte of the anode and cathode chambers. An alkyne substrate is added to the electrolyte of the cathode chamber to carry out an electrochemical deuteration reaction to synthesize deuterated olefin products.

[0019] Furthermore, in the application, the volume ratio of tetrahydrofuran to deuterated water is 1:2.5-3, the concentration of the K2CO3 solution in the electrolyte is 0.5 M, and the potential value of the constant potential is -1.1 to -1.5 V vs. Hg / HgO.

[0020] The beneficial effects of the present invention are:

[0021] 1) The present invention uses a conductive material as a substrate to enhance the electron transmission / mass transfer during the reaction process.

[0022] 2) The present invention adopts a square-wave cyclic electrodeposition method to achieve the controllable preparation of high-curvature PdSe nanoneedle tips, and uses Se doping through a simple baking process to precisely control the electronic structure of Pd.

[0023] 3) The present invention adopts high-curvature PdSe nano-needle-tip catalysts and uses cheap deuterated water as the deuterium source to achieve efficient electrocatalytic synthesis of alkynes to deuterated alkenes under room temperature. The reaction conditions are green and mild, the operation is simple, and it has excellent selectivity. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a SEM image of the high-curvature PdSe nano-needle-tip catalyst prepared in Example 3 of the present invention;

[0025] Figure 2 TEM image of the high-curvature PdSe nanotip catalyst prepared in Example 3 of the present invention;

[0026] Figure 3 This is a SEM image of the catalyst prepared in Example 11 of the present invention;

[0027] Figure 4This is a SEM image of the catalyst prepared in Example 12 of the present invention;

[0028] Figure 5 This is the mass spectrum of deuterated 1,1-diphenylethylene synthesized in Example 3 of the present invention. DETAILED DESCRIPTION

[0029] The present invention will be further described below with reference to specific embodiments, but the protection scope of the present invention is not limited thereto.

[0030] Example 1

[0031] 1×1cm 2 The nickel mesh was used as the working electrode substrate and was immersed in a centrifuge tube containing 2 mL of concentrated hydrochloric acid (mass fraction 36%) for 15 min, and then washed three times with deionized water and ethanol respectively; it was used as the cathode for square wave cyclic electrodeposition, and the anode electrode was 1×1 cm 2 Pt sheet, saturated calomel as the reference electrode, 19.8mgK2PdCl6 was added to 20mL0.25M H2SO4 solution and ultrasonically uniformly used as the deposition liquid. First, the working electrode potential was set from 0.8V to -0.7V and applied for 2000 cycles with a step time of 0.05 seconds; then the working electrode potential was set from 0.6V to 0.2V and applied for 20000 cycles with a step time of 0.005 seconds, and then rinsed and dried; then the dried sample was placed at one end of a porcelain boat, and 200mg Se powder was added to the other end (the Se powder side was located upstream of the gas flow). In an inert gas Ar atmosphere, the temperature was increased at a rate of 5℃ / min to 300℃ and kept constant for 2h. After cooling, the high-curvature PdSe nanoneedle tip catalyst was obtained.

[0032] Example 2

[0033] The preparation steps of the catalyst in Example 2 were repeated in Example 1, with the only difference being that "in the second cycle, the working electrode potential was stepped from 0.6 V to 0.2 V for 40,000 cycles" and the other conditions remained unchanged, ultimately producing a high-curvature PdSe nanotip catalyst.

[0034] Example 3

[0035] The preparation steps of the catalyst in Example 3 were repeated in Example 1, with the only difference being that "in the second cycle, the working electrode potential was stepped from 0.6 V to 0.2 V for 60,000 cycles" and the other conditions remained unchanged. Finally, a high-curvature PdSe nanoneedle-tip catalyst was obtained.

[0036] Example 4

[0037] The preparation steps of the catalyst in Example 4 were repeated in Example 1, with the only difference being that "in the second cycle, the working electrode potential was stepped from 0.6 V to 0.2 V for 80,000 cycles" and the other conditions remained unchanged. Finally, a high-curvature PdSe nanoneedle-tip catalyst was obtained.

[0038] Example 5

[0039] The preparation steps of the catalyst in Example 5 were repeated in Example 1, with the only difference being that "in the second cycle, the working electrode potential was stepped from 0.6 V to 0.2 V for 100,000 cycles" and the other conditions remained unchanged, ultimately producing a high-curvature PdSe nanotip catalyst.

[0040] Example 6

[0041] The preparation steps of the catalyst in Example 6 were repeated in Example 3, with the only difference being that the amount of Se powder was replaced with 100 mg. Other conditions remained unchanged, and finally a high-curvature PdSe nano-needle-tip catalyst was prepared.

[0042] Example 7

[0043] The preparation steps of the catalyst in Example 7 were repeated in Example 3, with the only difference being that the amount of Se powder was replaced with 300 mg. Other conditions remained unchanged, and finally a high-curvature PdSe nano-needle-tip catalyst was prepared.

[0044] Example 8

[0045] The preparation steps of the catalyst in Example 8 were repeated in Example 3, with the only difference being that the amount of Se powder was replaced with 400 mg. Other conditions remained unchanged, and finally a high-curvature PdSe nano-needle-tip catalyst was prepared.

[0046] Example 9

[0047] The preparation steps of the catalyst in Example 9 were repeated in Example 3, with the only difference being that the amount of Se powder was replaced with 500 mg. Other conditions remained unchanged, and finally a high-curvature PdSe nano-needle-tip catalyst was prepared.

[0048] Example 10

[0049] 1×1cm 2 The nickel mesh was used as the working electrode substrate and was immersed in a centrifuge tube containing 2 mL of concentrated hydrochloric acid for 15 min, then washed three times with deionized water and ethanol respectively; it was used as the cathode for square wave cyclic electrodeposition, and the anode electrode was 1×1 cm 2Pt sheet, saturated calomel as the reference electrode, 19.8mg K2PdCl6 was added to 20mL 0.25M H2SO4 solution for ultrasonic uniform deposition as the deposition solution. First, the working electrode potential was set from 0.8V to -0.7V for 2000 cycles with a step time of 0.005 seconds; then the working electrode potential was set from 0.6V to 0.2V for 60,000 cycles with a step time of 0.005 seconds, and then rinsed and dried; then the dried sample was placed in a porcelain boat, and in an inert gas Ar atmosphere, the temperature was increased at a rate of 5℃ / min to 300℃, and the temperature was maintained at a constant temperature for 2h. After cooling, a high-curvature Pd nanoneedle tip catalyst was obtained.

[0050] Example 11

[0051] 1×1cm 2 The nickel mesh was used as the working electrode substrate and was immersed in a centrifuge tube containing 2 mL of concentrated hydrochloric acid for 15 min, then washed three times with deionized water and ethanol respectively; it was used as the cathode for square wave cyclic electrodeposition, and the anode electrode was 1×1 cm 2 Pt sheet, saturated calomel as the reference electrode, 19.8mg K2PdCl6 was added to 20mL 0.25M H2SO4 solution and ultrasonically uniformly used as the deposition solution. First, the working electrode potential was set to step from 0.8V to -0.7V and applied for 2000 cycles with a step time of 0.05 seconds, and then rinsed and dried; then the dried sample was placed at one end of a porcelain boat, and 200mg Se powder was added to the other end (the Se powder side was located upstream of the gas flow). Under an inert gas Ar atmosphere, the temperature was increased at a rate of 5℃ / min to 300℃ and maintained at a constant temperature for 2h. After cooling, the high-curvature PdSe nanoneedle tip catalyst was obtained.

[0052] Example 12

[0053] 1×1cm 2 The nickel mesh was used as the working electrode substrate and was immersed in a centrifuge tube containing 2 mL of concentrated hydrochloric acid for 15 min, then washed three times with deionized water and ethanol respectively; it was used as the cathode for square wave cyclic electrodeposition, and the anode electrode was 1×1 cm 2 A Pt sheet and saturated calomel were used as a reference electrode. 19.8 mg of K2PdCl6 was added to 20 mL of 0.25 M H2SO4 solution and ultrasonically homogenized as a deposition solution. The working electrode potential was first set to step from 0.6 V to 0.2 V for 60,000 cycles with a step time of 0.005 seconds, and then rinsed and dried. The dried sample was then placed at one end of a porcelain boat, and 200 mg of Se powder was added to the other end (the Se powder side was located upstream of the gas flow). In an inert gas Ar atmosphere, the temperature was increased at a rate of 5°C / min to 300°C and maintained at a constant temperature for 2 hours. After cooling, the high-curvature PdSe nanoneedle-tip catalyst was obtained.

[0054] Examples 13-16

[0055] 1×1cm 2 The nickel mesh was used as the working electrode substrate and was immersed in a centrifuge tube containing 2 mL of concentrated hydrochloric acid for 15 min, then washed three times with deionized water and ethanol respectively; it was used as the cathode for square wave cyclic electrodeposition, and the anode electrode was 1×1 cm 2 Pt sheet, saturated calomel as reference electrode, 19.8mg K2PdCl6 was added to 20mL 0.25M H2SO4 solution and ultrasonically homogenized as deposition solution. First, the working electrode potential was set to step from 0.8V to -0.7V for 2000 cycles with a step time of 0.05 seconds; then the working electrode potential was set to step from 0.6V to 0.2V for 60000 cycles with a step time of 0.005 seconds, and then rinsed and dried; then the dried sample was placed at one end of the porcelain boat, and 400mg was added to the other end Se powder (one side of the Se powder is located upstream of the gas flow) is heated at a rate of 5°C / min to 200-600°C (the calcination temperature of Example 13 is 200°C, the calcination temperature of Example 14 is 400°C, the calcination temperature of Example 15 is 500°C, and the calcination temperature of Example 16 is 600°C) under an inert gas Ar atmosphere, and the constant temperature is maintained for 2 hours. After cooling, the high-curvature PdSe nanoneedle-tip catalyst can be obtained.

[0056] Comparative Example 1

[0057] 1×1cm 2 The nickel mesh was used as the working electrode substrate and was immersed in a centrifuge tube containing 2 mL of concentrated hydrochloric acid for 15 min, then washed three times with deionized water and ethanol respectively; it was used as the cathode for square wave cyclic electrodeposition, and the anode electrode was 1×1 cm 2 Pt sheet, saturated calomel as the reference electrode, 19.8mg K2PdCl6 was added to 20mL 0.25M H2SO4 solution and ultrasonically uniformly used as the deposition solution. First, the working electrode potential was set from 0.8V to -0.7V and applied for 2000 cycles with a step time of 0.05 seconds; then the working electrode potential was set from 0.6V to 0.2V and applied for 60,000 cycles with a step time of 0.005 seconds, and then rinsed and dried; then the dried sample was placed at one end of a porcelain boat, and 200mg S powder was added to the other end (the S powder side was located upstream of the gas flow). Under an inert gas Ar atmosphere, the temperature was increased at a rate of 5℃ / min to 300℃ and kept constant for 2h. After cooling, a high-curvature PdS nanoneedle-tip catalyst was obtained.

[0058] Comparative Example 2

[0059] 1×1cm 2The nickel mesh was used as the working electrode substrate and was immersed in a centrifuge tube containing 2 mL of concentrated hydrochloric acid for 15 min, then washed three times with deionized water and ethanol respectively; it was used as the cathode for square wave cyclic electrodeposition, and the anode electrode was 1×1 cm 2 Pt sheet, saturated calomel as the reference electrode, 19.8mg K2PdCl6 was added to 20mL 0.25M H2SO4 solution and ultrasonically uniformly used as the deposition solution. First, the working electrode potential was set from 0.8V to -0.7V and applied for 2000 cycles with a step time of 0.05 seconds; then the working electrode potential was set from 0.6V to 0.2V and applied for 60,000 cycles with a step time of 0.005 seconds, and then rinsed and dried; then the dried sample was placed at one end of a porcelain boat, and 200mg sodium hypophosphite was added to the other end (the sodium hypophosphite side was located upstream of the gas flow). Under an inert gas Ar atmosphere, the temperature was increased at a rate of 5℃ / min to 300℃ and kept at a constant temperature for 2h. After cooling, a high-curvature PdP nanoneedle tip catalyst was obtained.

[0060] Comparative Example 3

[0061] 1×1cm 2 The nickel mesh was used as the working electrode substrate and was immersed in a centrifuge tube containing 2 mL of concentrated hydrochloric acid for 15 min, then washed three times with deionized water and ethanol respectively; it was used as the cathode for square wave cyclic electrodeposition, and the anode electrode was 1×1 cm 2 Pt sheet, saturated calomel as the reference electrode, 19.8mg K2PdCl6 was added to 20mL 0.25M H2SO4 solution and ultrasonically uniformly used as the deposition solution. First, the working electrode potential was set from 0.8V to -0.7V and applied for 2000 cycles with a step time of 0.05 seconds; then the working electrode potential was set from 0.6V to 0.2V and applied for 60,000 cycles with a step time of 0.005 seconds, and then rinsed and dried; then the dried sample was placed at one end of a porcelain boat, and 200mg hydroxylamine hydrochloride was added to the other end (the hydroxylamine hydrochloride side was located upstream of the gas flow). Under an inert gas Ar atmosphere, the temperature was increased at a rate of 5℃ / min to 300℃ and kept constant for 2h. After cooling, a high-curvature PdN nanoneedle tip catalyst was obtained.

[0062] The SEM image and TEM image of the catalyst prepared in Example 3 of the present invention are as follows: Figure 1 and Figure 2 As shown, from Figure 1 It can be seen that a dense and orderly PdSe nanotip array is present on the nickel mesh substrate. Figure 2 This is also confirmed by the TEM image of Example 11. In contrast, in Example 11, only the first deposition cycle was applied, and its SEM image ( Figure 3) presents a granular shape; in Example 12, the second deposition cycle was applied directly without the first deposition cycle, and its SEM image ( Figure 4 ) No obvious material is present; this is due to the unique steps of the square wave cyclic deposition method. The first deposition cycle is the Pd crystal nucleus deposition step, and the second deposition cycle is the crystal nucleus growth step. For the preparation of high-curvature PdSe nanoneedle tips, both steps are indispensable.

[0063] The catalysts prepared in Examples 1-16 and Comparative Examples 1-3 of the present invention were used in the semideuteration reaction of diphenylacetylene, respectively. An electrochemical workstation was used as the electrochemical generator, and a three-electrode flow electrolyzer measurement system was employed. The cathode and anode chambers of the electrolyzer were separated by an anion exchange membrane. The catalyst served as the cathode working electrode, a carbon rod served as the anode counter electrode, and mercury / mercuric oxide served as the reference electrode. A 0.5 M K2CO3 mixed solution was prepared using a tetrahydrofuran / deuterated water mixed solution with a volume ratio of 2:5 as the solvent and potassium carbonate as the solute. The electrolyte in the cathode and cathode chambers was 8 mL in volume. 2 mmol of diphenylacetylene was added to the electrolyte in the cathode chamber to carry out the electrochemical deuteration reaction. A constant potential of -1.3 V vs. Hg / HgO was applied and the reaction was carried out for 3 h. After completion of the reaction, the conversion rate and selectivity were detected by gas chromatography-mass spectrometry, and the data were recorded for comparison. The performance parameters of the catalysts prepared in Examples 1-16 and Comparative Examples 1-3 in the catalytic reaction test are shown in Table 1.

[0064] Table 1 Summary of performance of different catalysts

[0065]

[0066]

[0067] The mass spectrum of deuterated 1,1-diphenylethylene synthesized in Example 3 of the present invention is as follows: Figure 5 As shown, the mass-to-charge ratio of deuterated 1,1-stilbene is 182.

[0068] Examples 1-5 mainly control the Pd loading in the catalyst by controlling the number of second deposition cycles in the square wave cyclic electrodeposition method. The Pd loading is tested by ICP-MS. When the number of cycles is 20,000, the Pd loading is 0.09 wt %, when the number of cycles is 40,000, the Pd loading is 0.17 wt %, when the number of cycles is 60,000, the Pd loading is 0.25 wt %, when the number of cycles is 80,000, the Pd loading is 0.32 wt %, and when the number of cycles is 100,000, the Pd loading is 0.49 wt %. As the number of cycles increases, the Pd loading increases. The performance test results are shown in Table 1, and the conversion rate increases and the selectivity shows a downward trend.

[0069] Examples 6-10 and 3 investigated the effect of different Se source dosages on catalyst performance during the calcination process. Performance test results showed that the performance was optimal when the Se source dosage was 200 mg in Example 3. When the Se source dosage was 0, the conversion rate was high, but the selectivity was low. When the Se source dosage was further increased, the conversion rate decreased. This was due to the electronic regulation effect of Se on Pd. Sufficient Se could poison the catalytic activity of Pd.

[0070] Examples 11 and 12 respectively explored the effects of cyclic square wave electrodeposition steps on its performance. The results showed that the dense and ordered PdSe nanotip array can effectively promote the semideuteration process of alkynes.

[0071] Examples 13-16 explored the effect of temperature on the catalytic activity of the catalyst during the calcination process. The higher the calcination temperature, the lower the alkyne conversion rate. This is because the higher the temperature, the more abundant the sublimated gaseous Se, and the stronger the poisoning effect on Pd. In addition, comparative examples 1-3 respectively electronically regulated Pd by different anions (S, P, and N). The test results further demonstrated the unique regulatory effect of Se on Pd, which promoted the electrocatalytic semideuteration process of alkynes to deuterated alkenes.

Claims

1. A method for preparing a high-curvature PdSe nano-needle-tip catalyst, characterized in that The following steps are involved: In the first step, a conductive material is used as the cathode substrate of the working electrode, a platinum sheet is used as the anode counter electrode, a Pd precursor is dissolved in an acidic aqueous solution as the electrolyte, and a cyclic square wave electrodeposition method is used to grow the Pd component on the substrate. The cyclic square wave electrodeposition method includes the following two steps: 1) Set the working electrode potential from 0.8 V ± 0.05 V to -0.7 V ± 0.05 V and apply multiple cycles; 2) Setting the working electrode potential from 0.6 V ± 0.05 V to 0.2 V ± 0.05 V for multiple cycles, followed by rinsing and drying; In the second step, the sample dried in the first step is selenized at high temperature in a tube furnace to obtain the high-curvature PdSe nano-needle-tip catalyst; The acidic aqueous solution is a low-concentration sulfuric acid solution or a hydrochloric acid solution, and its concentration is 0.1-1 M; The final concentration of the Pd precursor dissolved in the acidic aqueous solution was 1–10 mM; Step 1) The number of cycles is 500-3000 times, and the step time is 0.01-0.1 seconds; Step 2) The number of cycles is 50,000-100,000 times, and the step time is 0.001-0.01 seconds; The process in the high-temperature selenization step is: Se powder is placed upstream in a tube furnace, the dried sample is placed downstream in the tube furnace, and calcined under the condition of passing inert gas Ar or N2. The calcination temperature is 300-400°C, and the molar ratio of Se powder to the Pd precursor in the first step electrolyte is 25-75:

1.

2. The method for preparing a high-curvature PdSe nano-needle-tip catalyst according to claim 1, characterized in that The conductive material is one of carbon paper, carbon cloth, nickel foam and nickel mesh.

3. The method for preparing a high-curvature PdSe nano-needle-tip catalyst according to claim 1, characterized in that The Pd precursor is one of PdCl2, K2PdCl4, K2PdCl6, and Na2PdCl4.

4. The method for preparing a high-curvature PdSe nano-needle-tip catalyst according to claim 3, characterized in that The Pd precursor is K2PdCl6.

5. The method for preparing a high-curvature PdSe nano-needle-tip catalyst according to claim 1, characterized in that In the cyclic square wave electrodeposition method, the number of cycles in step 1) is 2000.

6. The method for preparing a high-curvature PdSe nano-needle-tip catalyst according to claim 1, characterized in that In the cyclic square wave electrodeposition method, the number of cycles in step 2) is 60,000.

7. A high-curvature PdSe nano-needle-tip catalyst prepared by the method according to any one of claims 1 to 6.

8. Use of a high-curvature PdSe nano-needle-tip catalyst in electrocatalytic synthesis of deuterated olefins according to claim 7, characterized in that The high-curvature PdSe nano-needle tip catalyst is used as a cathode working electrode for electrochemical reactions, and deuterated olefins are synthesized using deuterated water as a deuterium source and alkynes as substrates.

9. The use according to claim 8, characterized in that An electrochemical workstation is used as an electrochemical generating device, a three-electrode measurement system is adopted, the anode and cathode compartments of the electrolytic cell are separated by an anion exchange membrane, the high-curvature Pd nanotip catalyst is used as a cathode working electrode, a platinum sheet is used as a counter electrode, mercury / mercuric oxide is used as a reference electrode, a tetrahydrofuran / deuterium water mixed solution is used as a solvent, and potassium carbonate is used as a solute to prepare an electrolyte for the anode and cathode compartments. An alkyne substrate is added to the electrolyte in the cathode compartment, and an electrochemical deuteration reaction is carried out under constant potential to synthesize a deuterated olefin product. The volume ratio of tetrahydrofuran to deuterated water is 1:1-5, the concentration of potassium carbonate in the electrolyte is 0.1-1 M, and the potential value of the constant potential is -1.1-1.5 V vs. Hg / HgO.

10. The use according to claim 9, characterized in that The volume ratio of tetrahydrofuran to deuterated water is 1:2.5-3, and the concentration of potassium carbonate in the electrolyte is 0.5 M.

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