Anatase type TiO2 loaded RuCo nanocluster composite material as well as preparation method and application thereof

Abstract

The invention discloses an anatase type TiO2 loaded RuCo nanocluster composite material as well as a preparation method and application thereof, and belongs to the technical field of water electrolysis hydrogen production catalysts. The anatase type TiO2 loaded RuCo nanocluster composite material is of a two-dimensional lamellar structure and comprises two-dimensional lamellar anatase type TiO2 and a RuCo nanocluster, and the RuCo nanocluster is loaded on the surface of the two-dimensional lamellar anatase type TiO2. Two-dimensional lamellar MXene is loaded with RuCo nanoclusters through an impregnation method, Ti3C2Tx MXene is converted into anatase type TiO2 through annealing, the anatase type TiO2 has excellent thermodynamic and chemical stability, meanwhile, the two-dimensional lamellar structure is reserved, agglomeration of surface RuCo metal is restrained, and the use amount of the RuCo metal is reduced. And the RuCo metal exists on the surface of the carrier in the form of nanoclusters and has good dispersity, the utilization rate of metal sites is increased, and then excellent catalytic activity is presented.

Description

Technical Field

[0001] The present invention relates to the technical field of catalysts for hydrogen production by electrolysis of water, in particular to anatase-type TiO 2 Loaded RuCo nanocluster composite material and preparation method and application thereof. Background Art

[0002] Hydrogen production by water electrolysis is a process that uses electricity to decompose water into hydrogen and oxygen. This process is usually carried out in an electrolyzer. In order to increase the conductivity of the solution and reduce energy consumption, electrolytes are usually added to the water to increase conductivity. Under the action of direct current, the decomposition reaction occurs, and the positive electrode (anode) produces oxygen, while the negative electrode (cathode) produces hydrogen. Water electrolysis is an important method for producing high-purity hydrogen, which is of great significance for promoting the development of clean energy technologies such as hydrogen-powered vehicles and fuel cells.

[0003] Depending on the type of electrolyte used, water electrolysis can be divided into two main methods: alkaline electrolysis and acidic electrolysis. Since acidic water electrolysis can work at a higher current density and the system has the advantages of being able to start and stop quickly, it has become the focus of research and development in the field of water electrolysis for hydrogen production and has begun commercial application. However, acidic water electrolysis is highly oxidizing and corrosive, and only a few precious metal-based electrocatalysts such as platinum and iridium dioxide can exhibit good catalytic activity and stability under such working conditions. However, due to the high cost of these precious metals, more cost-effective alternatives need to be explored. Summary of the invention

[0004] The purpose of the present invention is to provide anatase TiO 2 The RuCo nanocluster-loaded composite material and its preparation method and application solve the problems of poor oxidation resistance and corrosion resistance and high cost of catalysts in the prior art.

[0005] To achieve the above object, the present invention provides an anatase TiO 2 Composite materials loaded with RuCo nanoclusters, anatase TiO 2 The RuCo nanocluster-loaded composite material is a two-dimensional lamellar structure, including two-dimensional lamellar anatase TiO 2 and RuCo nanoclusters, wherein the RuCo nanoclusters are supported on the two-dimensional lamellar anatase TiO 2 surface.

[0006] Preferably, the two-dimensional lamellar anatase TiO 2 The flake diameter is 5-50μm.

[0007] Preferably, the diameter of the RuCo nanoclusters is 1-5 nm.

[0008] Preferably, the mass ratio of Ru to Co in the RuCo nanoclusters is 40:(1-5).

[0009] The present invention also provides the above-mentioned anatase TiO 2 Preparation method of RuCo nanocluster loaded composite material, using impregnation method to load RuCo nanocluster on two-dimensional lamellar Ti 3 C 2 T x MXene surface, which is then annealed in a weakly oxidizing atmosphere; in MAX, M stands for early transition metals, A stands for aluminum, and X stands for carbon. MAX is a general term for transition metal carbide materials; in Ti 3 C 2 T x In MXene, T x Represents the functional group produced by the reaction.

[0010] The following steps are involved: (1) Ti 3 AlC 2 Preparation of MAX powder: Mix titanium powder, aluminum powder and carbon powder and stir them evenly. Sinter the mixed powder under an inert gas atmosphere, crush and grind it to obtain Ti 3 AlC 2 MAX powder; (2) Multi-layer accordion-shaped Ti 3 C 2 T x Preparation of MXene: Take the Ti obtained in step (1) 3 AlC 2 MAX powder is mixed with hydrofluoric acid solution, heated in a water bath, and stirred continuously. The suspension after the reaction is centrifuged, and the precipitate is repeatedly centrifuged, washed, filtered, and vacuum dried to obtain a multi-layer accordion-shaped Ti 3 C 2 T x MXene; (3) Two-dimensional lamellar Ti 3 C 2 T x Preparation of MXene: Take the multilayer accordion-shaped Ti obtained in step (2) 3 C 2 T x MXene and the intercalation agent are mixed and stirred to obtain a suspension, which is centrifuged until the pH value of the supernatant is 6.0-8.0, and the precipitate is retained. Deionized water is repeatedly added to the precipitate for dispersion and then centrifuged for the first time. The suspension is ultrasonicated in an ice bath under the action of inert gas bubbling, centrifuged for a long time to obtain a supernatant, and the supernatant is freeze-dried to obtain an aerogel-like freeze-dried powder, that is, a two-dimensional lamellar Ti 3 C2 T x MXene; (4) Two-dimensional lamellar anatase TiO 2 Preparation of RuCo nanocluster composite materials: Take the two-dimensional lamellar Ti obtained in step (3) 3 C 2 T x MXene was added to deionized water and RuCl was added dropwise 3 ·3H 2 O and Co(NO 3 ) 2 6H 2 O salt solution, stirred, ultrasonicated in an ice bath under the action of inert gas bubbling, centrifuged to obtain a precipitate, and the precipitate was repeatedly centrifuged and washed, and the mixture containing the precipitate after the final washing was freeze-dried to obtain a freeze-dried powder, and then the freeze-dried powder was annealed and kept warm in a weak oxidizing gas with an oxygen content of less than 0.001% to obtain a two-dimensional lamellar anatase TiO 2 Loaded RuCo nanocluster composites.

[0011] Preferably, in step (1), the molar ratio of titanium powder, aluminum powder and carbon powder is 3:1.2:1.9; The oxygen content in the inert gas atmosphere is less than 0.001%, and the flow rate of the inert gas in the tube furnace is 150-250cm 3 / min; The sintering is carried out by programmed temperature rise method, the heating rate from room temperature to 1200℃ is 10℃ / min, the heating rate from 1200℃ to sintering temperature is 2℃ / min, the sintering temperature is 1300-1600℃, and the sintering time is 6-12h; Ti 3 AlC 2 The particle size of MAX powder is 50-100 μm.

[0012] Typically, in this step, a mixed powder consisting of titanium powder, aluminum powder and carbon powder is spread flat in a corundum crucible and placed in a tube furnace to prepare Ti by a pressureless sintering method. 3 AlC 2 MAX powder, cooled to room temperature after sintering. After the sintered sample was taken out, the sintered block was crushed with a carbide hammer, and then ground into Ti in an agate mortar with a grinding pestle. 3 AlC 2 MAX powder. Controlled grinding Ti 3 AlC 2 The particle size of MAX powder makes Ti 3 AlC 2 MAX powder is fully in contact with the etchant in the subsequent steps, resulting in better etching effect.

[0013] Preferably, in step (2), the mass concentration of hydrofluoric acid is 40-50%; Ti 3 AlC 2 The mass volume ratio of MAX powder to hydrofluoric acid solution is 1: (10-20) g / mL; The water bath heating temperature is 40-60°C, the stirring speed is 300-500r / min, and the water bath heating and stirring time is 48-72h; the centrifugal speed is 4000-6000r / min, and the centrifugal time is 3-8min; the standard for the completion of precipitate cleaning is that the pH value of the supernatant is between 6.0-8.0; the vacuum drying time is 24-48h.

[0014] In this step, hydrofluoric acid solution is used as an etchant, Ti 3 AlC 2 MAX powder is etched into multi-layer Ti by etchant 3 C 2 T x MXene, this multilayer Ti 3 C 2 T x MXene is accordion-shaped, and the etching process is usually carried out in a polytetrafluoroethylene container with magnetic stirring to make Ti 3 AlC 2 The MAX powder is in full contact with the etchant.

[0015] Preferably, in step (3), the intercalant is any one or more of tetramethylammonium hydroxide, tetrapropylammonium hydroxide and tetrabutylammonium hydroxide, and the mass concentration of the intercalant is 10-15wt%; the multilayer accordion-shaped Ti 3 C 2 T x The mass volume ratio of MXene to intercalant is 1:(10-40) g / mL; Step (3) is carried out in a weakly oxidizing gas with an oxygen content of less than 0.001%, the speed of the initial centrifugation is 4000-6000 r / min, and the time is 3-8 min; the ultrasonic treatment time is 1-2 h; the speed of the long-term centrifugation is 3000-4000 r / min, and the long-term centrifugation time is 50-70 min; the freeze-drying time is 48-72 h.

[0016] In this step, the multi-layer accordion-shaped Ti 3 C 2 T xMXene and intercalation agent form a suspension, the suspension is separated by centrifugation, the precipitate is washed several times, and the intercalation agent is removed. After the intercalation agent is removed, the precipitate is dispersed again with deionized water. Usually, the amount of deionized water used is 10-20 times the mass of the precipitate. 3 C 2 T x When MXene and the intercalation agent are mixed, they can be mixed evenly by hand shaking. Usually, the mixture is shaken for 5-15 minutes. This manual shaking is convenient to operate and can mix evenly.

[0017] Preferably, in step (4), the two-dimensional lamellar Ti 3 C 2 T x The mass volume ratio of MXene to deionized water is 2: (1-10) mg / mL; RuCl 3 ·3H 2 O and Co(NO 3 ) 2 6H 2 The mass concentration of O was 10-20 mg / mL; The stirring speed is 1000-1500r / min, and the stirring time is 30-60min; the ultrasonication is carried out in a weak oxidizing gas with an oxygen content of less than 0.001%, and the time is 30-60min; the centrifugal speed is 4000-6000r / min, the centrifugal time is 3-8min, and the number of centrifugation is 2-4 times; the freeze-drying time is 48-72h; the freeze-dried powder is annealed and kept warm in a tubular furnace, and the flow rate of the weak oxidizing gas in the tubular furnace is 50-150cm 3 / min; the heating rate from room temperature to annealing temperature is 5℃ / min, the annealing temperature is 400-600℃, and the holding time is 1-3 h.

[0018] The purpose of stirring and ice bath ultrasound in this step of the immersion method is to mix the solution so that the RuCo metal ions are successfully loaded on the Ti 3 C 2 T x MXene surface. After repeated washing of the precipitate and the unloaded metal salt solution, the resulting precipitate is a two-dimensional lamellar anatase TiO 2 Precursor of RuCo loaded nanocluster composites.

[0019] The anatase TiO 2 The RuCo nanocluster-loaded composite materials are used in the preparation of catalysts for hydrogen production by water electrolysis.

[0020] The flaky anatase TiO 2It has a two-dimensional lamellar structure and is a two-dimensional lamellar Ti 3 C 2 Tx MXene is obtained by oxidation of its own functional groups. It is an excellent catalytic material that has both the two-dimensional lamellar morphology of MXene and strong corrosion resistance and oxidation resistance. 2 It has a tetragonal crystal structure with a space group of I41 / amd. Due to its high electron mobility, low dielectric constant, excellent chemical stability and corrosion resistance, it plays an important role in various catalytic fields.

[0021] Moreover, the RuCo nanoclusters included in the present invention are microscopic particles composed of dozens to hundreds of atoms, have a large specific surface area, increase the number of surface active sites, improve the catalytic reaction efficiency, and reduce the metal loading, greatly reducing the cost of the catalyst. In addition, due to the synergistic effect between Ru and Co metals in the RuCo nanoclusters, the electronic structures of the two are microscopically regulated, further reducing the reaction energy barrier and promoting the occurrence of the catalytic reaction.

[0022] Therefore, the present invention adopts the above-mentioned anatase TiO 2 The RuCo nanocluster-loaded composite material and its preparation method and application have the following beneficial effects: (1) The present invention firstly prepares Ti by pressureless sintering method. 3 AlC 2 MAX powder has the advantages of low cost, simple operation and safe operation; then, the present invention will Ti 3 AlC 2 MAX powder made of few-layer Ti 3 C 2 T x MXene powder, RuCo nanoclusters loaded on Ti by impregnation method 3 C 2 T x The MXene carrier surface is simple to operate, has mild conditions, no special requirements for equipment, short production time and low production cost; finally, the rich functional groups on the MXene surface are used to anneal and keep warm in a weak oxidizing atmosphere (oxygen content is less than 0.001%), thereby realizing the two-dimensional lamellar Ti 3 C 2 T x MXene to two-dimensional lamellar anatase TiO 2 Therefore, the two-dimensional lamellar rutile TiO 2 The preparation method of the RuCo nanocluster composite material has mild conditions, does not require a high-pressure environment, has low cost, high yield, is easy to industrialize, and greatly reduces the production cost of the catalyst; (2) The composite material structure of the present invention is a two-dimensional lamellar anatase TiO 2 Surface-loaded RuCo nanoclusters, two-dimensional lamellar anatase TiO 2 It has a large specific surface area and excellent thermodynamic stability and corrosion resistance. At the same time, RuCo nanoclusters not only have good catalytic activity, but also effectively reduce the loading amount of precious metals, thereby effectively reducing the production cost of the catalyst, and are widely used in water electrolysis hydrogen production catalysts.

[0023] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The two-dimensional lamellar anatase TiO obtained in Examples 1 to 3 of the present invention 2 Hydrogen evolution polarization curves obtained by linear sweep voltammetry of RuCo nanocluster-loaded composite materials in alkaline electrolyte; Figure 2 The two-dimensional lamellar anatase TiO obtained in Example 1 of the present invention 2 RuCo / TiO composites loaded with RuCo nanoclusters 2 -1 The converted hydrogen evolution Tafel slope curve obtained by linear sweep voltammetry test in alkaline electrolyte; Figure 3 The two-dimensional lamellar anatase TiO obtained in Example 2 of the present invention 2 RuCo / TiO composites loaded with RuCo nanoclusters 2 -2 The converted hydrogen evolution Tafel slope curve was measured by linear sweep voltammetry in alkaline electrolyte; Figure 4 The two-dimensional lamellar anatase TiO obtained in Example 3 of the present invention 2 RuCo / TiO composites loaded with RuCo nanoclusters 2 -0.5 The converted hydrogen evolution Tafel slope curve obtained by linear sweep voltammetry test in alkaline electrolyte; Figure 5 The two-dimensional lamellar anatase TiO obtained in Example 1 of the present invention 2 Hydrogen evolution polarization curves obtained by linear sweep voltammetry test of RuCo nanocluster-loaded composite materials in acidic electrolyte; Figure 6 The two-dimensional lamellar anatase TiO obtained in Example 1 of the present invention 2 The converted hydrogen evolution Tafel slope curve of the RuCo nanocluster composite material was tested by linear sweep voltammetry in acidic electrolyte; Figure 7The two-dimensional lamellar anatase TiO obtained in Example 1 of the present invention 2 CV curves of RuCo nanocluster composites at different scan rates obtained by cyclic voltammetry in acidic electrolyte; Figure 8 The two-dimensional lamellar anatase TiO obtained in Example 1 of the present invention 2 RuCo / TiO composites loaded with RuCo nanoclusters 2 -1's X-ray diffraction pattern; Fig. 9 The two-dimensional lamellar anatase TiO obtained in Example 1 of the present invention 2 RuCo / TiO composites loaded with RuCo nanoclusters 2 -1 scanning electron microscope image; Fig.10 The two-dimensional lamellar anatase TiO obtained in Example 1 of the present invention 2 RuCo / TiO composites loaded with RuCo nanoclusters 2 -1 scanning electron microscope image; Fig.11 The two-dimensional lamellar anatase TiO2 loaded RuCo nanocluster composite material RuCo / TiO obtained in Example 1 of the present invention 2 High-angle annular dark-field scanning transmission electron microscopy image of -1. DETAILED DESCRIPTION

[0025] Unless otherwise defined, technical or scientific terms used in the present invention shall have the common meanings understood by one having ordinary skills in the field to which the present invention belongs.

[0026] The present invention provides an anatase TiO 2 Composite materials loaded with RuCo nanoclusters, anatase TiO 2 The RuCo nanocluster-loaded composite material is a two-dimensional lamellar structure, including two-dimensional lamellar anatase TiO 2 and RuCo nanoclusters, wherein the RuCo nanoclusters are supported on the two-dimensional lamellar anatase TiO 2 surface.

[0027] Two-dimensional lamellar anatase TiO 2 The diameter of the RuCo nanocluster is 5-50 μm. The diameter of the RuCo nanocluster is 1-5 nm. The mass ratio of Ru to Co in the RuCo nanocluster is 40: (1-5).

[0028] The present invention also provides the above-mentioned anatase TiO 2Preparation method of RuCo nanocluster loaded composite material, using impregnation method to load RuCo nanocluster on two-dimensional lamellar Ti 3 C 2 T x MXene surface, which is then annealed in a weakly oxidizing atmosphere; in MAX, M stands for early transition metals, A stands for aluminum, and X stands for carbon. MAX is a general term for transition metal carbide materials; in Ti 3 C 2 T x In MXene, T x Represents the functional group produced by the reaction.

[0029] The following steps are involved: (1) Ti 3 AlC 2 Preparation of MAX powder: Mix titanium powder, aluminum powder and carbon powder and stir them evenly. Sinter the mixed powder under an inert gas atmosphere, crush and grind it to obtain Ti 3 AlC 2 MAX powder. In this step, the molar ratio of titanium powder, aluminum powder and carbon powder is 3:1.2:1.9; the oxygen content in the inert gas atmosphere is less than 0.001%, and the flow rate of the inert gas in the tube furnace is 150-250 cm 3 / min.

[0030] The sintering is carried out by programmed temperature rise method, the heating rate from room temperature to 1200℃ is 10℃ / min, the heating rate from 1200℃ to sintering temperature is 2℃ / min, the sintering temperature is 1300-1600℃, and the sintering time is 6-12h; Ti 3 AlC 2 The particle size of MAX powder is 50-100 μm.

[0031] Typically, in this step, a mixed powder consisting of titanium powder, aluminum powder and carbon powder is spread flat in a corundum crucible and placed in a tube furnace to prepare Ti by a pressureless sintering method. 3 AlC 2 MAX powder, cooled to room temperature after sintering. After the sintered sample was taken out, the sintered block was crushed with a carbide hammer, and then ground into Ti in an agate mortar with a grinding pestle. 3 AlC 2 MAX powder. Controlled grinding Ti 3 AlC 2 The particle size of MAX powder makes Ti 3 AlC 2 MAX powder is fully in contact with the etchant in the subsequent steps, resulting in better etching effect.

[0032] (2) Multi-layer accordion-shaped Ti 3 C 2 T x Preparation of MXene: Take the Ti obtained in step (1) 3 AlC 2 MAX powder is mixed with hydrofluoric acid solution, heated in a water bath, and stirred continuously. The suspension after the reaction is centrifuged, and the precipitate is repeatedly centrifuged, washed, filtered, and vacuum dried to obtain a multi-layer accordion-shaped Ti 3 C 2 T x MXene. In this step, the mass concentration of hydrofluoric acid is 40-50%; Ti 3 AlC 2 The mass volume ratio of MAX powder to hydrofluoric acid solution is 1: (10-20) g / mL. The water bath heating temperature is 40-60°C, the stirring speed is 300-500 r / min, and the water bath heating and stirring time is 48-72h; the centrifugal speed is 4000-6000 r / min, and the centrifugal time is 3-8min; the standard for the completion of sediment cleaning is that the pH value of the supernatant is between 6.0-8.0; the vacuum drying time is 24-48h.

[0033] In this step, hydrofluoric acid solution is used as an etchant, Ti 3 AlC 2 MAX powder is etched into multi-layer Ti by etchant 3 C 2 T x MXene, this multilayer Ti 3 C 2 T x MXene is accordion-shaped, and the etching process is usually carried out in a polytetrafluoroethylene container with magnetic stirring to make Ti 3 AlC 2 The MAX powder is in full contact with the etchant.

[0034] (3) Two-dimensional lamellar Ti 3 C 2 T x Preparation of MXene: Take the multilayer accordion-shaped Ti obtained in step (2) 3 C 2 T x MXene and the intercalation agent are mixed and stirred to obtain a suspension, which is centrifuged until the pH value of the supernatant is 6.0-8.0, and the precipitate is retained. Deionized water is repeatedly added to the precipitate for dispersion and then centrifuged for the first time. The suspension is ultrasonicated in an ice bath under the action of inert gas bubbling, centrifuged for a long time to obtain a supernatant, and the supernatant is freeze-dried to obtain an aerogel-like freeze-dried powder, that is, a two-dimensional lamellar Ti 3 C 2 T xMXene; in this step, the intercalation agent is any one or more of tetramethylammonium hydroxide, tetrapropylammonium hydroxide and tetrabutylammonium hydroxide, and the mass concentration of the intercalation agent is 10-15wt%; multilayer accordion-shaped Ti 3 C 2 T x The mass volume ratio of MXene to intercalant is 1:(10-40) g / mL.

[0035] Step (3) is carried out in a weakly oxidizing gas with an oxygen content of less than 0.001%, the speed of the initial centrifugation is 4000-6000 r / min, and the time is 3-8 min; the ultrasonic treatment time is 1-2 h; the speed of the long-term centrifugation is 3000-4000 r / min, and the long-term centrifugation time is 50-70 min; the freeze-drying time is 48-72 h.

[0036] In this step, the multi-layer accordion-shaped Ti 3 C 2 T x MXene and intercalation agent form a suspension, the suspension is separated by centrifugation, the precipitate is washed several times, and the intercalation agent is removed. After the intercalation agent is removed, the precipitate is dispersed again with deionized water. Usually, the amount of deionized water used is 10-20 times the mass of the precipitate. 3 C 2 T x When MXene and the intercalation agent are mixed, they can be mixed evenly by hand shaking. Usually, the mixture is shaken for 5-15 minutes. This manual shaking is convenient to operate and can mix evenly.

[0037] (4) Two-dimensional lamellar anatase TiO 2 Preparation of RuCo nanocluster composite materials: Take the two-dimensional lamellar Ti obtained in step (3) 3 C 2 T x MXene was added to deionized water and RuCl was added dropwise 3 ·3H 2 O and Co(NO 3 ) 2 6H 2 O salt solution, stirred, ultrasonicated in an ice bath under the action of inert gas bubbling, centrifuged to obtain a precipitate, and the precipitate was repeatedly centrifuged and washed, and the mixture containing the precipitate after the final washing was freeze-dried to obtain a freeze-dried powder, and then the freeze-dried powder was annealed and kept warm in a weak oxidizing gas with an oxygen content of less than 0.001% to obtain a two-dimensional lamellar anatase TiO 2 Loaded RuCo nanocluster composites.

[0038] In step (4), the two-dimensional lamellar Ti3 C 2 T x The mass volume ratio of MXene to deionized water is 2: (1-10) mg / mL; RuCl 3 ·3H 2 O and Co(NO 3 ) 2 6H 2 The mass concentration of O is 10-20 mg / mL. The stirring speed is 1000-1500r / min, and the stirring time is 30-60min. Ultrasonication is performed in a weak oxidizing gas with an oxygen content of less than 0.001% for 30-60min. The centrifugal speed is 4000-6000r / min, the centrifugal time is 3-8min, and the number of centrifugation is 2-4 times. The freeze-drying time is 48-72h. The freeze-dried powder is annealed and kept warm in a tubular furnace, and the flow rate of the weak oxidizing gas in the tubular furnace is 50-150cm 3 / min; the heating rate from room temperature to annealing temperature is 5℃ / min, the annealing temperature is 400-600℃, and the holding time is 1-3 h.

[0039] The purpose of stirring and ice bath ultrasound in this step of the immersion method is to mix the solution so that the RuCo metal ions are successfully loaded on the Ti 3 C 2 T x MXene surface. After repeated washing of the precipitate and the unloaded metal salt solution, the resulting precipitate is a two-dimensional lamellar anatase TiO 2 Precursor of RuCo loaded nanocluster composites.

[0040] The anatase TiO 2 The RuCo nanocluster-loaded composite materials are used in the preparation of catalysts for hydrogen production by water electrolysis.

[0041] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments.

[0042] In addition, it should be understood that although this specification is described according to the implementation modes, not every implementation mode includes only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation modes that can be understood by those skilled in the art. These other implementation modes are also covered within the protection scope of the present invention.

[0043] Embodiment 1 This embodiment provides an anatase TiO 2The preparation method of the RuCo nanocluster loaded composite material comprises the following steps: 1) Ti 3 AlC 2 Preparation of MAX powder Take titanium powder, aluminum powder and carbon powder, mix them in a molar ratio of 3:1.2:1.9, stir them evenly, spread them in a corundum crucible and place them in a tube furnace; at a flow rate of 150 cm 3 / min in a weakly oxidizing atmosphere (oxygen content less than 0.001%), the temperature was raised from room temperature to 1200°C at a rate of 10°C / min, and from 1200°C to 1550°C at a rate of 2°C / min. The sintering was carried out at 1550°C for 6 h, and then cooled to room temperature. The sintered block was crushed with a carbide hammer and then ground into Ti particles with a particle size of 100 μm in an agate mortar with a grinding pestle. 3 AlC 2 MAX Powder.

[0044] 2) Multi-layer accordion-shaped Ti 3 C 2 T x Preparation of MXene Take the Ti obtained in step 1) 3 AlC 2 2 g of MAX powder was placed in a polytetrafluoroethylene container, and then 20 mL of a 40% hydrofluoric acid solution was added. The suspension was stirred at a stirring speed of 500 r / min for 72 h at a water bath temperature of 50 °C to obtain a suspension. The suspension was centrifuged at a speed of 5000 r / min for 5 min to obtain a precipitate, which was washed with deionized water until the pH value of the supernatant was 6. The mixture was filtered and the sample was placed in a vacuum drying oven for 36 h to obtain a multilayer accordion-shaped TiO2 film. 3 C 2 T x MXene.

[0045] 3) Two-dimensional lamellar Ti 3 C 2 T x Preparation of MXene Take the multilayer accordion-shaped Ti obtained in step 2) 3 C 2 T x0.6 g of MXene powder was added to 15 mL of tetramethylammonium hydroxide intercalant with a mass concentration of 10 wt%, and stirred by hand for 5 min to obtain a suspension; the suspension was centrifuged at 5000 r / min for 5 min to obtain a precipitate, and the precipitate was dispersed with deionized water and continued to be centrifuged with the same parameters until the pH value of the supernatant was 8. The precipitate was dispersed again with 30 mL of deionized water, and under the action of argon bubbling, it was ultrasonically treated in an ice bath for 1 h, and centrifuged at 3000 r / min for a long time for 60 min to obtain a supernatant; the supernatant was freeze-dried for 60 h to obtain an aerogel-like freeze-dried powder, that is, a two-dimensional lamellar Ti 3 C 2 T x MXene.

[0046] 4) Two-dimensional lamellar anatase TiO 2 Preparation of RuCo nanocluster-loaded composite materials Take the two-dimensional lamellar Ti obtained in step 3) 3 C 2 T x 0.1 g of MXene powder was added to 50 mL of deionized water, and 2.5 mL of 10 mg / mL RuCl was added dropwise at a stirring speed of 1500 r / min. 3 ·3H 2 O salt solution and 2.5 mL of 10 mg / mL Co(NO 3 ) 2 6H 2 O salt solution; stirring at a stirring speed of 1500r / min for 30min, the suspension was subjected to ultrasonic treatment in an ice bath for 1h under the action of argon bubbling, and the suspension was centrifuged at a speed of 5000r / min for 5min to obtain a precipitate, which was washed with deionized water, and the washing was repeated 3 times, and the precipitate was dispersed again with 30mL of deionized water to obtain a mixture; the mixture was freeze-dried for 60h to obtain a freeze-dried powder, i.e., a two-dimensional lamellar anatase TiO 2 Precursor of RuCo nanocluster composite material; the precursor is spread in a corundum crucible and placed in a tube furnace at a flow rate of 100 cm 3 / min in a weakly oxidizing atmosphere (oxygen content less than 0.001%), the heating rate from room temperature to 500 °C was 5 °C / min, the temperature was kept for 2 h, and then the temperature was cooled to room temperature to obtain a two-dimensional lamellar anatase TiO 2 The RuCo nanocluster composite material is named RuCo / TiO 2 -1.

[0047] Embodiment 2 This embodiment provides an anatase TiO2 The preparation method of the RuCo nanocluster composite material is different from that of Example 1 in that: Step 4) a two-dimensional lamellar anatase TiO 2 Preparation of RuCo nanocluster composite materials. Step 4) in this embodiment is: take the two-dimensional lamellar Ti obtained in step 3) 3 C 2 T x 0.1 g of MXene powder was added to 50 mL of deionized water, and 2.5 mL of 20 mg / mL RuCl was added dropwise at a stirring speed of 1500 r / min. 3 ·3H 2 O salt solution and 2.5 mL of 10 mg / mL Co(NO 3 ) 2 6H 2 O salt solution; stirring at a stirring speed of 1500 r / min for 30 min, the suspension was subjected to ultrasonic treatment in an ice bath for 1 h under the action of argon bubbling, and then the suspension was centrifuged at a speed of 5000 r / min for 5 min to obtain a precipitate, which was washed with deionized water, and repeated 3 times, and the precipitate was dispersed again with 30 mL of deionized water to obtain a mixture; the mixture was freeze-dried for 60 h to obtain a freeze-dried powder, namely, a two-dimensional lamellar anatase TiO 2 Precursor of RuCo nanocluster composite material; the precursor is spread in a corundum crucible and placed in a tube furnace at a flow rate of 100 cm 3 / min in a weakly oxidizing atmosphere (oxygen content less than 0.001%), the heating rate from room temperature to 500 °C was 5 °C / min, the temperature was kept for 2 h, and then the temperature was cooled to room temperature to obtain a two-dimensional lamellar anatase TiO 2 The RuCo nanocluster composite material is named RuCo / TiO 2 -2.

[0048] Embodiment 3 This embodiment provides a two-dimensional lamellar anatase TiO 2 The preparation method of the RuCo nanocluster composite material is different from that of Example 1 only in that: Step 4) Preparation of a two-dimensional lamellar anatase TiO2-loaded RuCo nanocluster composite material. Step 4) of this embodiment is: Take the two-dimensional lamellar TiO2 obtained in step 3) 3 C 2 T x 0.1 g of MXene powder was added to 50 mL of deionized water, and 2.5 mL of 10 mg / mL RuCl was added dropwise at a stirring speed of 1500 r / min. 3 ·3H 2O salt solution and 2.5 mL of 20 mg / mL Co(NO 3 ) 2 6H 2 O salt solution; stirring at a stirring speed of 1500 r / min for 30 min, the suspension was subjected to ice bath ultrasonic treatment for 1 h under the action of argon bubbling, and then the suspension was centrifuged at a speed of 5000 r / min for 5 min to obtain a precipitate, which was washed with deionized water, and repeated 3 times, and the precipitate was dispersed again with 30 mL of deionized water to obtain a mixture; the mixture was freeze-dried for 60 h to obtain a freeze-dried powder, namely, a two-dimensional lamellar anatase TiO 2 Precursor of RuCo nanocluster composite material; the precursor is spread in a corundum crucible and placed in a tube furnace at a flow rate of 100 cm 3 / min in a weakly oxidizing atmosphere (oxygen content less than 0.001%), the heating rate from room temperature to 500 °C was 5 °C / min, the temperature was kept for 2 h, and then the temperature was cooled to room temperature to obtain anatase TiO with a two-dimensional lamellar structure. 2 The RuCo nanocluster composite material is named RuCo / TiO 2 -0.5.

[0049] Experiment 1 The three two-dimensional lamellar anatase TiO 2 RuCo nanocluster composite material-RuCo / TiO 2 -1. RuCo / TiO 2 -2 and RuCo / TiO 2 -0.5 as three samples. Take 10 mg of two-dimensional lamellar anatase TiO 2 The RuCo nanocluster composite material was uniformly mixed with 5 mg of acetylene black, and 200 μL of anhydrous ethanol and 200 μL of 5% Nafion solution were added. The suspension was ultrasonically treated for 10 min to obtain a suspension. The suspension was slowly and evenly added to the surface of the carbon fiber cloth and vacuum dried for 10 min to prepare the carbon fiber cloth coated with the composite material. The carbon fiber cloth coated with three samples was clamped with a platinum electrode clamp as the working electrode, the platinum sheet was used as the counter electrode, and the Hg / HgO electrode was used as the reference electrode to form a three-electrode device, which was placed on the CHI1140C electrochemical workstation produced by Shanghai Chenhua Instrument Co., Ltd. At 25°C and 1M KOH solution, at room temperature, the linear sweep voltammetry was used to determine the hydrogen evolution polarization curve of the composite material. The linear sweep voltammetry measurement was carried out in the range of -0.9~-2.5V (relative to the Hg / HgO reference electrode) at 5 mV / s. The hydrogen evolution polarization curves obtained by the linear sweep voltammetry test of the three samples in alkaline electrolyte are as follows Figure 1 As shown; the linear sweep voltammetry test of three samples in alkaline electrolyte obtained by conversion of hydrogen evolution Tafel slope curve is as follows Figure 2-4 The experimental results are shown in Table 1, and the converted reversible hydrogen electrode (RHE) potentials are listed in Table 1.

[0050] Table 1 Electrochemical measurement results of different composite materials in alkaline electrolyte ;

[0051] Depend on Figure 1 , Figure 2-4 As can be seen from Table 1, the two-dimensional lamellar anatase TiO 2 The RuCo nanocluster-loaded composite materials all exhibited good hydrogen evolution performance in alkaline electrolyte, among which the RuCo / TiO 2 -1 has the lowest hydrogen evolution overpotential, which means that at the same current density, the catalyst can more effectively reduce the energy required for the reaction, thereby significantly reducing the cost of hydrogen production. 2 -1 has the lowest Tafel slope, indicating that the overpotential of the composite material increases slowly when the current density increases, and the catalyst can achieve a higher reaction rate at a relatively low overpotential.

[0052] Experiment 2 The two-dimensional lamellar anatase TiO prepared in Example 1 2 RuCo / TiO composites loaded with RuCo nanoclusters 2 -1, take 10 mg of two-dimensional lamellar anatase TiO 2 The RuCo nanocluster composite material was uniformly mixed with 5 mg of acetylene black, and 200 μL of anhydrous ethanol and 200 μL of 5% Nafion solution were added. The suspension was ultrasonically treated for 10 min to obtain a suspension. The suspension was slowly and evenly added to the surface of the carbon fiber cloth and vacuum dried for 10 min to prepare a carbon fiber cloth coated with the composite material. A platinum electrode clamp was used to clamp the carbon fiber cloth coated with Example 1 as the working electrode, a platinum sheet was used as the counter electrode, and a saturated calomel electrode was used as the reference electrode to form a three-electrode device, which was placed on a CHI1140C electrochemical workstation produced by Shanghai Chenhua Instrument Co., Ltd. at 25°C and 0.5MH 2 SO 4 The hydrogen evolution polarization curve of the composite material was determined by linear sweep voltammetry at room temperature in the solution. The linear sweep voltammetry was measured in the range of -0.2 to -2 V (relative to saturated calomel reference electrode) at a scan rate of 5 mV / s. The results are shown in Figure 5 As shown, the linear sweep voltammetry test obtained by conversion of the hydrogen evolution Tafel slope curve is as follows Figure 6 As shown, the above results are converted into reversible hydrogen electrode (RHE) potentials and listed in Table 2. The CV curves of the composite materials at different scan rates were measured by cyclic voltammetry to fit the electrochemical double layer capacitance of the composite materials. The cycle stability was measured in the voltage window of -0.1~0 V (relative to saturated calomel reference electrode) at scan rates of 120, 100, 80, 60, 40 and 20 mV / s, respectively. The results are shown in Table 2. Figure 7 As shown, the fitting results in the table are listed in Table 2.

[0053] Table 2 Electrochemical measurement results of Example 1 in acidic electrolyte ;

[0054] Depend on Figure 5 , Figure 6 , Figure 7 As can be seen from Table 2, the two-dimensional lamellar anatase TiO 2 The RuCo nanocluster composite material also has excellent catalytic activity in acidic electrolytes, with low hydrogen evolution overpotential and excellent Tafel slope at different current densities, which effectively reduces the energy required for acidic water electrolysis. 2 Excellent corrosion resistance, two-dimensional lamellar anatase TiO 2 The RuCo nanocluster-loaded composite material still has good stability in the strong oxidation and strong corrosion environment of the acidic electrolyte. Combined with the good dispersibility and low metal loading characteristics of the RuCo nanocluster, the cost of the catalyst is greatly reduced. 2 The RuCo nanocluster composite material has a strength of 21.0 mF / cm 2 The electrochemical double-layer capacitance means that it can provide more active sites during the electrolytic water decomposition reaction and accelerate the interaction between the catalyst reaction interface and the electrolyte.

[0055] Experiment 3 The two-dimensional lamellar anatase TiO prepared in Example 1 2 RuCo / TiO composites loaded with RuCo nanoclusters 2 -1 was analyzed on an Empyrean X-ray diffractometer produced by PANalytical BV of the Netherlands. The results are as follows: Figure 8 As shown by Figure 8 It can be seen that the two-dimensional lamellar anatase TiO 2 Anatase TiO in RuCo-loaded Nanocluster Composites 2The purity is extremely high, and no Ru or Co metal peaks can be found, which proves that RuCo metal has good dispersion and no obvious agglomeration, thus having a high metal atom utilization rate.

[0056] Experiment 4 The two-dimensional lamellar anatase TiO prepared in Example 1 2 RuCo / TiO composites loaded with RuCo nanoclusters 2 -1 was observed on a Quattro S scanning electron microscope produced by Thermo Fisher Scientific (TMO) in the United States. The results are as follows Figure 7 as well as Figure 8 As shown. Fig. 9 and Fig.10 It can be seen that the two-dimensional lamellar anatase TiO 2 Two-dimensional lamellar anatase TiO in RuCo-loaded nanocluster composites 2 The flake diameter is 5-50 μm and is evenly distributed in the field of view in the form of nano-thin flakes. 2 The two-dimensional lamellar structure of MXene is retained, and a large specific surface area is used to load RuCo nanoclusters, thereby improving the catalytic activity of the material. 2 Excellent thermodynamic stability and corrosion resistance further inhibit the corrosion of catalytic materials in acidic and alkaline environments, thereby better preserving the overall structure and active sites of the catalyst.

[0057] Experiment 5 The two-dimensional lamellar anatase TiO2-loaded RuCo nanocluster composite material prepared in Example 1 was placed on a Talos F200S scanning transmission electron microscope produced by Thermo Fisher (TMO) in the United States for observation. The results are as follows: Fig.11 shown.

[0058] Depend on Fig.11 It can be seen that the two-dimensional lamellar anatase TiO 2 Anatase TiO in RuCo-loaded Nanocluster Composites 2 It exists in the form of thin flakes and has a large specific surface area. RuCo nanoclusters are evenly distributed in the form of bright spots on the two-dimensional lamellar anatase TiO 2 The surface greatly reduces the metal loading while retaining the catalytic activity, thereby improving the utilization rate of active metal atoms.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. Anatase TiO2 loaded RuCo nanocluster composite material, characterized in that: The anatase TiO2 loaded RuCo nanocluster composite material is a two-dimensional lamellar structure, comprising two-dimensional lamellar anatase TiO2 and RuCo nanocluster, wherein the RuCo nanocluster is loaded on the surface of the two-dimensional lamellar anatase TiO2.

2. The anatase TiO2-loaded RuCo nanocluster composite material according to claim 1, characterized in that: The two-dimensional lamellar anatase TiO2 has a sheet diameter of 5-50 μm.

3. The anatase TiO2-loaded RuCo nanocluster composite material according to claim 1, characterized in that: The diameter of the RuCo nanoclusters is 1-5 nm.

4. The anatase TiO2-loaded RuCo nanocluster composite material according to claim 1, characterized in that: The mass ratio of Ru to Co in the RuCo nanocluster is 40:(1-5).

5. The method for preparing the anatase TiO2-loaded RuCo nanocluster composite material according to any one of claims 1 to 4, characterized in that: RuCo nanoclusters were loaded on two-dimensional lamellar Ti3C2T by impregnation method. x The MXene surface is then transformed by annealing in a weakly oxidizing atmosphere; The following steps are involved: (1) Preparation of Ti3AlC2 MAX powder: titanium powder, aluminum powder and carbon powder are mixed and stirred evenly, the mixed powder is sintered under an inert gas atmosphere, and then crushed and ground to obtain Ti3AlC2 MAX powder; (2) Multilayer accordion-shaped Ti3C2T x Preparation of MXene: Take the Ti3AlC2 MAX powder obtained in step (1), mix it with the hydrofluoric acid solution, heat it in a water bath, and stir it continuously. Centrifuge the suspension after the reaction, take the precipitate and wash it repeatedly by centrifugation, filter it, and vacuum dry it to obtain a multi-layer accordion-shaped Ti3C2T x MXene; (3) Two-dimensional lamellar Ti3C2T x Preparation of MXene: Take the multilayer accordion-shaped Ti3C2T obtained in step (2) x MXene and the intercalation agent are mixed and stirred to obtain a suspension, which is centrifuged until the pH value of the supernatant is 6.0-8.0, and the precipitate is retained. Deionized water is repeatedly added to the precipitate for dispersion and then centrifuged for the first time. The suspension is ultrasonicated in an ice bath under the action of inert gas bubbling, centrifuged for a long time, and the supernatant is obtained. The supernatant is freeze-dried to obtain an aerogel-like freeze-dried powder, that is, a two-dimensional lamellar Ti3C2T x MXene; (4) Preparation of two-dimensional lamellar anatase TiO2-loaded RuCo nanocluster composite material: Take the two-dimensional lamellar Ti3C2T x MXene is added to deionized water, and a salt solution of RuCl3·3H2O and Co(NO3)2·6H2O is added dropwise, stirred, and ultrasonicated in an ice bath under the action of inert gas bubbling. The precipitate is centrifuged to obtain a precipitate, and the precipitate is repeatedly centrifuged and washed. The mixture containing the precipitate after final cleaning is freeze-dried to obtain a freeze-dried powder. The freeze-dried powder is then annealed and kept warm in a weakly oxidizing gas with an oxygen content of less than 0.001% to obtain a two-dimensional lamellar rutaceous TiO2-loaded RuCo nanocluster composite material.

6. The method for preparing the anatase TiO2-loaded RuCo nanocluster composite material according to claim 5, characterized in that: In step (1), the molar ratio of titanium powder, aluminum powder and carbon powder is 3:1.2:1.9; The oxygen content in the inert gas atmosphere is less than 0.001%, and the flow rate of the inert gas in the tube furnace is 150-250 cm 3 / min; The sintering is carried out by a programmed temperature rising method, the heating rate from room temperature to 1200°C is 10°C / min, the heating rate from 1200°C to the sintering temperature is 2°C / min, the sintering temperature is 1300-1600°C, and the sintering time is 6-12h; the particle size of the Ti3AlC2 MAX powder is 50-100 μm.

7. The method for preparing the anatase TiO2-loaded RuCo nanocluster composite material according to claim 5, characterized in that: In step (2), the mass concentration of hydrofluoric acid is 40-50%; the mass volume ratio of Ti3AlC2 MAX powder to hydrofluoric acid solution is 1: (10-20) g / mL; The water bath heating temperature is 40-60°C, the stirring speed is 300-500r / min, and the water bath heating and stirring time is 48-72h; the centrifugal speed is 4000-6000r / min, and the centrifugal time is 3-8min; the standard for the completion of precipitate cleaning is that the pH value of the supernatant is between 6.0-8.0; the vacuum drying time is 24-48h.

8. The method for preparing anatase TiO2-loaded RuCo nanocluster composite material according to claim 5, characterized in that: In step (3), the intercalant is any one or more of tetramethylammonium hydroxide, tetrapropylammonium hydroxide and tetrabutylammonium hydroxide, and the mass concentration of the intercalant is 10-15wt%; the multilayer accordion-shaped Ti3C2T x The mass volume ratio of MXene to intercalant is 1:(10-40) g / mL; Step (3) is carried out in a weakly oxidizing gas with an oxygen content of less than 0.001%, the speed of the initial centrifugation is 4000-6000 r / min, and the time is 3-8 min; the ultrasonic treatment time is 1-2 h; the speed of the long-term centrifugation is 3000-4000 r / min, and the long-term centrifugation time is 50-70 min; the freeze-drying time is 48-72 h.

9. The method for preparing anatase TiO2-loaded RuCo nanocluster composite material according to claim 5, characterized in that: In step (4), the two-dimensional lamellar Ti3C2T x The mass volume ratio of MXene to deionized water is 2: (1-10) mg / mL; the mass concentrations of RuCl3·3H2O and Co(NO3)2·6H2O are both 10-20 mg / mL; The stirring speed is 1000-1500r / min, and the stirring time is 30-60min; the ultrasonication is carried out in a weak oxidizing gas with an oxygen content of less than 0.001%, and the time is 30-60min; the centrifugal speed is 4000-6000r / min, the centrifugal time is 3-8min, and the number of centrifugation is 2-4 times; the freeze-drying time is 48-72h; the freeze-dried powder is annealed and kept warm in a tubular furnace, and the flow rate of the weak oxidizing gas in the tubular furnace is 50-150cm 3 / min; the heating rate from room temperature to annealing temperature is 5℃ / min, the annealing temperature is 400-600℃, and the holding time is 1-3 h.

10. Use of the anatase TiO2-loaded RuCo nanocluster composite material according to any one of claims 1 to 4, characterized in that: The anatase TiO2-loaded RuCo nanocluster composite material is used in the field of preparing catalysts for hydrogen production by water electrolysis.

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