阅读说明：本技术 一种铼基硫氧化物复合纳米材料及其制备方法和应用 (Rhenium-based sulfur oxide composite nano material and preparation method and application thereof ) 是由 熊杰 黄建文 杜新川 郭倚天 李瑶瑶 晏超贻 邬春阳 王显福 于 2020-12-25 设计创作，主要内容包括：本发明提供一种铼基硫氧化物复合纳米材料及其制备方法和应用,属于催化材料制备技术领域,具体涉及一种ReS-2-ReO-3复合纳米材料及其制备方法,以及在电催化析氢反应中的应用。本发明利用氧等离子在ReS-2纳米片阵列表面原位氧化,生成片状ReS-2表面均匀分布的ReO-3颗粒,形成的ReS-2/ReO-3异质结构可以为析氢反应提供更多且催化效率更高的活性位点。本发明提供的具有ReS-2/ReO-3异质界面的硫氧化物复合纳米材料电极在电解水的阴极析氢反应中表现出高催化活性与持续电解稳定性,且其成本较低,合成工艺简单,易于规模化生产。(The invention provides a rhenium-based sulfur oxide composite nano material and a preparation method and application thereof, belongs to the technical field of preparation of catalytic materials, and particularly relates to a ReS 2 ‑ReO 3 A composite nano material, a preparation method thereof and application thereof in electrocatalytic hydrogen evolution reaction. The invention utilizes oxygen plasma in ReS 2 The surface of the nano-sheet array is oxidized in situ to generate sheet ReS 2 Uniformly distributed ReO on surface 3 Particles, formed ReS 2 /ReO 3 The heterostructure can provide more active sites for hydrogen evolution reactions with higher catalytic efficiency. The invention provides a polypeptide having the amino acid sequence ReS 2 /ReO 3 The sulfur oxide composite nano material electrode with the heterogeneous interface shows high catalytic activity and continuous electrolytic stability in the cathode hydrogen evolution reaction of electrolyzed water, and has the advantages of low cost, simple synthesis process and easy large-scale production.)

1. The rhenium-based sulfur oxide composite nano material is characterized in that the nano material is ReS₂Nanosheets and the nanosheets being uniformly distributed in the ReS₂ReO on nanosheets₃Nanoparticles of which ReO₃The diameter of the nano particles is less than 200nm, and the ReS of the nano flaky structure₂Provides rich specific surface area and good electron transport capacity, and the ReS is constructed in situ₂/ReO₃The heterostructure recombination sites play a role in enhancing the rate of the oxygen catalytic reaction.

2. The rhenium-based sulfur oxide composite nanomaterial of claim 1, wherein the ReO is₃The nano-particle is ReS₂The sheet-shaped nano structure is generated in situ by oxygen plasma etching.

3. A preparation method of rhenium-based sulfur oxide composite nano material is characterized by comprising the following steps:

step 1: mixing a rhenium source and a sulfur source according to a molar ratio of 1: (5-10), adding deionized water, and performing ultrasonic dissolution and uniform mixing to obtain a precursor mixed solution, wherein the concentration of a rhenium source is 10-30 mmol/L;

step 2: putting the conductive substrate subjected to hydrophilic treatment into the precursor mixed solution prepared in the step 1, and performing ultrasonic treatment;

and step 3: transferring the precursor solution soaked with the conductive substrate obtained after the ultrasonic treatment in the step (2) into a hydrothermal reaction kettle for hydrothermal reaction, and naturally cooling after the reaction is finished;

and 4, step 4: taking out the conductive substrate, cleaning and drying to obtain the ReS₂A conductive substrate of nanoplatelets;

and 5: the load ReS obtained in the step 4₂And (3) carrying out oxygen plasma treatment on the conductive substrate with the nanosheet structure to obtain the rhenium-based oxysulfide composite nanomaterial on the conductive substrate.

4. The method for preparing a rhenium-based sulfur oxide composite nanomaterial according to claim 3, wherein the rhenium source in step 1 is ReO-containing₄ ^-The water-soluble salt of ion, sulfur source is the micromolecule reductant containing sulfur atom.

5. As claimed in claim4, the method for preparing the rhenium-based oxysulfide composite nanomaterial is characterized in that the ReO-containing material₄ ^-The water-soluble salt of the ion is preferably NH₄ReO₄Or NaReO₄(ii) a The small molecule reducing agent containing sulfur atoms is preferably thiourea or thioacetamide.

6. The method of preparing a rhenium-based sulfur oxide composite nanomaterial according to claim 3, wherein the conductive substrate in step 2 is a flexible substrate or a hard substrate.

7. The method for preparing the rhenium-based sulfur oxide composite nanomaterial according to claim 3, wherein the hydrothermal reaction in step 3 is carried out at 190-220 ℃ for 18-32 hours.

8. The method for preparing a rhenium based sulfur oxide composite nanomaterial as claimed in claim 3, wherein the cleaning in step 4 is specifically performed by washing with alcohol, 50% alcohol, and water for 2-3 times; the drying conditions are as follows: drying at 40-70 ℃ under vacuum.

9. The method for preparing a rhenium-based sulfur oxide composite nanomaterial as claimed in claim 3, wherein the specific parameter conditions of the oxygen plasma treatment in the step 5 are as follows: the plasma power is 60-150W, and the processing time is 1-90 s.

10. The invention also provides an electrochemical application of the rhenium based sulfur oxide composite nano material as defined in claim 1 as a cathode material for electrolyzing water.

Technical Field

The invention belongs to the technical field of preparation of catalytic materials, and particularly relates to a ReS₂-ReO₃A composite nano material, a preparation method thereof and application thereof in electrocatalytic hydrogen evolution reaction.

Background

The development of the hydrogen fuel cell industry enables green high-yield hydrogen production to become an upstream key industry, and the water electrolysis hydrogen production technology matched with renewable energy systems such as photoelectricity and wind power provides a feasible scheme for large-scale hydrogen production with high efficiency and low cost. The key technical bottleneck of the water electrolysis hydrogen production technology lies in the high-activity and high-stability electrocatalyst, which comprises a cathode hydrogen evolution catalyst and an anode oxygen evolution catalyst. The traditional hydrogen evolution catalyst mainly adopts a platinum noble metal-based material, has high cost, and has important significance for technical progress and application in order to balance the relationship between cost and performance and develop a novel non-noble metal-based catalyst.

In MoS₂The two-dimensional material represented by the method is a hot material of a novel catalyst by virtue of a unique two-dimensional sheet structure. However, the large-area planar sites of most two-dimensional materials have poor activity, and researchers adopt various technical schemes in order to increase the active sites and further improve the performance of the two-dimensional materials. For example: zhou et al (ACS Nano 2018,12,4486-4493) reported a defect-rich ReS₂The catalyst realizes the regulation and control of the electronic state of the catalytic site at 147mV by defects to 10mA cm^-2Current density of (d); meng et al (Nano Energy 2019,61, 611-₂The graphene composite material realizes 10mA cm at 143mV under the three-dimensional structure and the electronic action^-2Current density of (d); by a similar method Gao et al, by passing ReS₂Compounded with graphene, 5.2mA cm is realized under the overpotential of 250mV^-2Current density (Rare Met.2018,12, 1014-1020); bolar et al(appl.Catal.B: environ.2019,254,432-442) reports a V-doped MoS₂The powder is used for electrocatalytic hydrogen evolution and realizes 10mA cm at 194mV^-2Current density of (d); wang et al (Small 2020,16,1905738) reported an O and P co-doped MoS₂Nanosheet material, achieving 10mA cm at about 240mV^-2The current density of (1).

Despite the many efforts and advances made by researchers, the material activity still does not meet the requirements for more efficient use.

Disclosure of Invention

Aiming at the problems existing in the background technology, the invention aims to provide a rhenium-based sulfur oxide composite nano material and a preparation method thereof. The invention utilizes oxygen plasma in ReS₂In-situ oxidation of the surface of the nano-sheet array in a sheet-shaped ReS₂Surface generation of uniformly distributed ReO₃Particles, formed ReS₂/ReO₃The heterostructure can provide more active sites for hydrogen evolution reactions with higher catalytic efficiency. The invention provides a polypeptide having the amino acid sequence ReS₂/ReO₃The sulfur oxide composite nano material electrode with the heterogeneous interface shows high catalytic activity and continuous electrolytic stability in the cathode hydrogen evolution reaction of electrolyzed water, and has the advantages of low cost, simple synthesis process and easy large-scale production.

In order to achieve the purpose, the technical scheme of the invention is as follows:

the rhenium-based sulfur oxide composite nano material is characterized in that the nano material is ReS₂Nanosheets and the nanosheets being uniformly distributed in the ReS₂ReO on nanosheets₃Nanoparticles of which ReO₃The diameter of the nano particles is less than 200nm, and the ReS of the nano flaky structure₂Provides rich specific surface area and good electron transport capacity, and the ReS is constructed in situ₂/ReO₃The heterostructure recombination sites play a role in enhancing the rate of the oxygen catalytic reaction.

Further, the ReO₃The nano-particle is ReS₂The sheet-shaped nano structure is generated in situ by oxygen plasma etching.

A preparation method of rhenium-based sulfur oxide composite nano material comprises the following steps:

step 1: mixing a rhenium source and a sulfur source according to a molar ratio of 1: (5-10), adding deionized water, and performing ultrasonic dissolution and uniform mixing to obtain a precursor mixed solution, wherein the concentration of a rhenium source is 10-30 mmol/L;

step 2: putting the conductive substrate subjected to hydrophilic treatment into the precursor mixed solution prepared in the step 1, and carrying out ultrasonic treatment for 10-15 min to enable the solution to completely infiltrate the surface of the conductive substrate;

and step 3: transferring the precursor solution soaked with the conductive substrate obtained in the step (2) into a hydrothermal reaction kettle for hydrothermal reaction, and naturally cooling after the reaction is finished;

and 4, step 4: taking out the conductive substrate, cleaning and drying to obtain the ReS₂A conductive substrate of nanoplatelets;

and 5: the load ReS obtained in the step 4₂And (3) carrying out oxygen plasma treatment on the conductive substrate with the nanosheet structure to obtain the rhenium-based oxysulfide composite nanomaterial on the conductive substrate.

Further, in step 1, the rhenium source is ReO-containing₄ ^-Water-soluble salts of ions, preferably NH₄ReO₄、NaReO₄And the sulfur source is thiourea, thioacetamide and other small molecular reducing agents containing sulfur atoms.

Further, the conductive substrate in step 2 is a flexible substrate such as carbon cloth or a hard substrate such as FTO.

Further, the hydrothermal reaction in the step 3 is carried out under the conditions of 190-220 ℃ for 18-32 hours.

Further, washing the cleaning object with alcohol, 50% alcohol and water for 2-3 times in the step 4; the drying conditions are as follows: and drying at 40-70 ℃ in vacuum to remove adsorbed water, ethanol and sulfur source micromolecules.

Further, the specific parameter conditions of the oxygen plasma treatment in the step 5 are as follows: the plasma power is 60-150W, and the processing time is 1-90 s.

The invention also provides the electrochemical application of the rhenium-based sulfur oxide composite nano material as an electrolytic water cathode material.

In summary, due to the adoption of the technical scheme, the invention has the beneficial effects that:

1. the invention provides a rhenium-based sulfur oxide composite nano material, and ReS in the material₂And ReO₃A composite nano interface is formed, and a new active site is introduced into the interface and the catalytic activity of the interface is enhanced; sheet-grown ReS₂Provides rich specific surface area and provides more reaction sites for the formation of a composite nano interface.

2. The invention provides a preparation method of a rhenium-based sulfur oxide composite nano material, which regulates and controls ReO by regulating the time of in-situ oxygen plasma oxidation reaction₃Thereby obtaining the nano rhenium-based sulfur oxide with a reasonable composite structure.

3. The electrode loaded with the rhenium-based sulfur oxide composite nano material provided by the invention shows high catalytic performance in hydrogen evolution reaction, and electrochemical test results prove that the rhenium-based sulfur oxide composite nano material electrode is acidic (0.5M H)₂SO₄) Under the condition, only 121mV overpotential is needed to generate 10mA cm^-2Current density of (d), Tafel slope reached 107mV dec by in situ oxygen plasma treatment^-1The improvement effect of the reasonably designed composite structure on the catalytic activity is proved, and the reasonably designed composite structure has an obvious improvement effect on the catalytic activity.

Drawings

Fig. 1 is an X-ray diffraction analysis chart of the rhenium-based sulfur oxide composite nanomaterial obtained in example 1, example 2, and example 3 of the present invention.

FIG. 2 is a scanning electron microscope image of the rhenium-based sulfur oxide composite nanomaterial obtained in example 4 of the present invention.

FIG. 3 shows that the rhenium based sulfur oxide composite nanomaterial obtained in examples 1, 2, and 3 of the present invention is 0.5M H₂SO₄The electrochemical performance characterization diagram of the hydrogen evolution reaction in (1);

wherein, (a) is a comparison graph of polarization curves of rhenium-based sulfur oxide composite nano-materials under different oxygen plasma treatments; (b) corresponding tafel slope plots.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the following embodiments and accompanying drawings.

The rhenium-based sulfur oxide composite nano material is characterized in that the nano material is ReS₂Nanosheets and the nanosheets being uniformly distributed in the ReS₂ReO on nanosheets₃Nanoparticles of which ReO₃The diameter of the nano particles is less than 200nm, and the ReS of the nano flaky structure₂Provides rich specific surface area and good electron transport capacity, and the ReS is constructed in situ₂/ReO₃The heterostructure recombination sites play a role in enhancing the rate of the oxygen catalytic reaction.

Example 1

A preparation method of rhenium-based sulfur oxide composite nano material comprises the following steps:

step 1: reacting NH₄ReO₄And thiourea in a molar ratio of 1: 10, adding deionized water, and performing ultrasonic dissolution and uniform mixing to obtain a precursor mixed solution, wherein the concentration of the Re source is 20 mmol/L;

step 2: putting the carbon cloth substrate subjected to hydrophilic treatment into the precursor mixed solution prepared in the step 1, and performing ultrasonic treatment for 15min to enable the solution to completely infiltrate the surface of the conductive substrate;

and step 3: putting the precursor solution soaked with the conductive substrate obtained in the step 2 into a hydrothermal reaction kettle, reacting for 26 hours at 200 ℃, and naturally cooling after the reaction is finished;

and 4, step 4: taking out the carbon cloth after the hydrothermal reaction, washing the carbon cloth with alcohol, 50% alcohol and water for 3 times, and drying the carbon cloth at 60 ℃ for 10 hours in vacuum to obtain the ReS-loaded carbon cloth₂Carbon cloth of nanosheets;

and 5: the load ReS obtained in the step 4₂And (3) carrying out oxygen plasma treatment on the carbon cloth of the nanosheet, wherein the plasma power is 100W, and the treatment time is 10s, so that the required rhenium-based sulfur oxide composite nanomaterial can be obtained on the carbon cloth.

Prepared in this exampleThe X-ray diffraction XRD characterization pattern of the rhenium-based sulfur oxide composite nano material is shown in figure 1, and the carbon cloth electrode loaded with the rhenium-based sulfur oxide composite nano material is 0.5M H₂SO₄The test curve of the electrochemical performance of the hydrogen evolution reaction is shown in figure 3.

Example 2

A rhenium-based sulfur oxide composite nanomaterial was prepared by following the procedure of example 1, adjusting only the oxygen plasma treatment time in step 5 to 5s, with the other steps unchanged.

An X-ray diffraction XRD characterization pattern of the rhenium-based sulfur oxide composite nanomaterial obtained in this example is shown in fig. 1, where the carbon cloth electrode loaded with the rhenium-based sulfur oxide composite nanomaterial is 0.5M H₂SO₄The test curve of the electrochemical performance of the hydrogen evolution reaction is shown in figure 3.

Example 3

A rhenium-based sulfur oxide composite nanomaterial was prepared by following the procedure of example 1, with the oxygen plasma treatment time adjusted to 30s only in step 5, and the other steps being unchanged.

An X-ray diffraction XRD characterization pattern of the rhenium-based sulfur oxide composite nanomaterial obtained in example 3 is shown in fig. 1, where the carbon cloth electrode loaded with the rhenium-based sulfur oxide composite nanomaterial is 0.5M H₂SO₄The test curve of the electrochemical performance of the hydrogen evolution reaction is shown in figure 3.

Example 4

A rhenium-based sulfur oxide composite nanomaterial was prepared by following the procedure of example 1, adjusting only the oxygen plasma treatment time in step 5 to 20s, with the other steps unchanged.

An electron microscope SEM picture of the rhenium based sulfur oxide composite nanomaterial obtained in this example is shown in fig. 2.

FIG. 1 is an XRD diffraction pattern of rhenium based sulfur oxide composite nanomaterials obtained in example 1, example 2 and example 3, with different oxygen plasma treatment times, wherein ReS₂/ReO₃-5 represents a plasma treatment time of 5 s; ReS₂/ReO₃-10 represents a plasma treatment time of 10 s; ReS₂/ReO₃-30 represents a plasma treatment time ofFor 30 s. As can be seen, ReO is observed with the oxygen plasma treatment time being prolonged₃The diffraction peak of (1) is enhanced, indicating that ReO is₃The amount of sulfur oxide generated gradually increases with the increase of the plasma treatment time, and the sulfur oxide recombination interface sites generated gradually increase, but with the increase of the surface ReO at longer treatment time₃The increased number of particles, the plasma may have an etching effect on the particles generated. FIG. 2 is an SEM photograph of the rhenium based sulfur oxide composite nanomaterial obtained in example 4, from which it can be seen that nano-ReS grows in a sheet-like manner₂Uniformly growing on the surface of a carbon cloth substrate, and treating with oxygen plasma in ReS₂The R eO with the size of about 100nm is generated between the nano-sheet arrays₃And (3) nanoparticles. FIG. 3(a) is a comparison of polarization curves of rhenium-based sulfur oxide composite nanomaterial electrodes obtained in example 1, example 2, and example 3 for different plasma treatment times; FIG. 3(b) shows the corresponding Tafel slope. As can be seen from the diagram of the polarization curve, the load ReS₂/ReO₃-10 carbon cloth electrode of composite nanomaterial with dec of 107mV at hydrogen evolution reaction^-1And only a minimum overpotential of 121mV is needed to reach 10mA cm^-2The above current densities illustrate the comparison to ReS alone₂，ReS₂/ReO₃The composite material has better catalytic activity, which shows that the simple and rapid method for preparing the rhenium-based sulfur oxide composite nano material electrode by using the oxygen plasma has good applicability.

While the invention has been described with reference to specific embodiments, any feature disclosed in this specification may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise; all of the disclosed features, or all of the method or process steps, may be combined in any combination, except mutually exclusive features and/or steps.