Molybdenum disulfide / cerium oxide composite material, preparation method thereof and hydrogen production method

Abstract

The invention relates to the field of composite materials, in particular to a molybdenum disulfide / cerium oxide composite material and a preparation method thereof, and a method for producing hydrogen by using the molybdenum disulfide / cerium oxide composite material. The molybdenum disulfide / cerium oxide composite material comprises MoS2 and CeO2 loaded on the surface of the MoS2, and based on the total weight of the molybdenum disulfide / cerium oxide composite material, the content of the CeO2 is 0.1-10 wt%, and the content of the MoS2 is 90-99.9 wt%. The specific heterojunction catalyst can be well matched with ionization irradiation, so that irradiation hydrogen production is realized, radiation energy of nuclear waste, which is dangerous and difficult to utilize, can be utilized, clean energy is generated, and the blank in the aspect of a method for producing hydrogen through irradiation matched with the catalyst in the prior art is filled. The hydrogen production method is high in hydrogen evolution efficiency.

Description

Technical Field

[0001] The present invention relates to the field of composite materials, and particularly to a molybdenum disulfide / cerium oxide composite material and a preparation method thereof, as well as a method for producing hydrogen using the molybdenum disulfide / cerium oxide composite material. Background Art

[0002] The progress of technology is inseparable from the support of energy. However, the current energy consumption structure mainly based on fossil fuels not only causes the rapid consumption of energy, but also brings the problem of a large amount of pollutant emissions. Therefore, the utilization of efficient and clean energy is a worldwide problem to be solved at present. Hydrogen is a super-clean secondary energy source, and is increasingly valued for its high combustion calorific value, renewable, clean and pollution-free, convenient transportation and storage, etc. Many photocatalysts have been reported to be able to catalyze the production of hydrogen from aqueous solutions.

[0003] As an effective clean energy, how to utilize nuclear energy reflects the comprehensive strength level of a country's economy, industry and technology. Nuclear waste generally refers to the radioactive waste that is no longer needed in nuclear fuel production, processing and nuclear reactors. These nuclear wastes themselves will emit a large amount of radiation energy and have not been effectively utilized.

[0004] Therefore, a way to utilize radiation energy is needed. For example, a method of using radiation energy to split water into hydrogen has not been seen yet. Summary of the Invention

[0005] The purpose of the present invention is to overcome the above problems existing in the prior art, and provides a molybdenum disulfide / cerium oxide composite material and a preparation method thereof, as well as a method for producing hydrogen using the molybdenum disulfide / cerium oxide composite material. The molybdenum disulfide / cerium oxide composite material of the present invention affects the internal lattice structure through ionization irradiation treatment. Under the action of ionization irradiation, electrons and holes in the lattice are excited to generate ionization phenomena, thereby improving the catalytic performance and catalytic stability of the composite material, and at the same time ensuring the hydrogen production efficiency of the composite material as a catalyst in the field of irradiation catalytic hydrogen production.

[0006] Heterojunction is a new type of high-performance photocatalytic composite material, and it has currently been used as a catalyst to prepare clean energy - hydrogen from water or organic solutions. The inventors of the present invention found that the heterojunction composite material can not only respond to light, but also change the internal lattice structure under the influence of ionization irradiation, thereby affecting the properties and performance of the material. Therefore, a technical solution of combining ionization irradiation with heterojunction composite material for catalytic hydrogen production was proposed, and further research found a heterojunction composite material with better synergistic effect with ionization irradiation.

[0007] The first aspect of the present invention provides a molybdenum disulfide / cerium oxide composite material, including MoS 2and the load on the MoS 2 surface of CeO 2 , based on the total weight of the molybdenum disulfide / cerium oxide composite material, the content of the CeO 2 is 0.1-10% by weight, and the content of the MoS 2 is 90-99.9% by weight.

[0008] The second aspect of the present invention provides a method for preparing the molybdenum disulfide / cerium oxide composite material of the first aspect, including: performing a hydrothermal reaction on a suspension containing water, CeO 2 nanoparticles, a Mo source, and a reducing agent.

[0009] The third aspect of the present invention provides a hydrogen production method, which includes ionizing radiation of water or an organic solution in the presence of a catalyst, and the catalyst is the molybdenum disulfide / cerium oxide composite material of the first aspect of the present invention and / or the molybdenum disulfide / cerium oxide composite material prepared by the method of the second aspect.

[0010] This molybdenum disulfide / cerium oxide composite material of the present invention is particularly suitable for use as a catalyst for irradiation catalytic hydrogen production, making the irradiation catalytic hydrogen production have better hydrogen evolution efficiency.

[0011] Compared with the prior art, the advantages of the technical solution of the present application are at least further:

[0012] (1) The molybdenum disulfide / cerium oxide composite material of the present invention has a huge two-dimensional nanointerface, providing rich channels for the induced charge transfer between cerium oxide and molybdenum disulfide, effectively accelerating the transfer and separation of carriers, and accelerating the charge transfer rate in the heterojunction compartment, so that the molybdenum disulfide / cerium oxide composite material heterojunction catalyst has excellent catalytic performance and catalytic stability;

[0013] (2) Due to its large two-dimensional nanointerface, the molybdenum disulfide / cerium oxide composite material of the present invention has excellent electron absorption and storage capabilities, and also provides more reactive sites for ionization irradiation catalytic hydrogen production, effectively improving the hydrogen evolution efficiency of irradiation hydrogen production;

[0014] (3) According to a preferred embodiment, after the molybdenum disulfide / cerium oxide composite material of the present invention is subjected to ionization irradiation treatment, electrons and holes inside the composite material are excited and ionization occurs, so that the molybdenum disulfide / cerium oxide composite material can achieve better catalytic hydrogen evolution effect.

[0015] (4) The molybdenum disulfide / cerium oxide composite material of the present invention can be recycled repeatedly and has good stability, further promoting the industrialization process of catalytic water hydrogen evolution.

[0016] Other features and advantages of the present invention will be described in detail in the following specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Shown is a molybdenum disulfide / cerium oxide composite material;

[0018] Figure 2 Shown is CeO 2 nanoparticles. SPECIFIC EMBODIMENTS

[0019] The endpoints and any values disclosed herein are not limited to the exact ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, between the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values, they can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed herein.

[0020] The first aspect of the present invention provides a molybdenum disulfide / cerium oxide composite material, including MoS 2 and CeO 2 loaded on the surface of the MoS 2 . Based on the total weight of the molybdenum disulfide / cerium oxide composite material, the content of the CeO 2 is 0.1-10% by weight, and the content of the MoS 2 is 90-99.9% by weight.

[0021] The inventors of the present invention have found that although MoS 2 is not active in the sunlight-driven hydrogen evolution reaction, due to the highly exposed edges of the MoS 2 crystal layer, it is particularly suitable for forming a synergistic effect with other materials because it can provide a potential driving force, contribute to the separation of photoexcited charge carriers, dominate the transfer direction, increase the contact interface, and accelerate the charge transfer rate within the heterojunction compartment. The inventors of the present invention have further found that CeO 2 is particularly suitable for cooperating with MoS 2 . Thus, MoS 2 acts as a p-type semiconductor, and CeO 2 acts as an n-type semiconductor to form a tight contact region, promoting the formation of carriers at the interface. The MoS 2 / CeO 2 catalyst has a huge two-dimensional nanointerface, providing rich channels for the induced charge transfer between cerium oxide and molybdenum disulfide. The large two-dimensional nanointerface can effectively accelerate the transfer and separation of carriers, endowing it with excellent electron absorption and storage capabilities, thereby enabling MoS 2The MoS₂ / CeO₂ heterojunction catalyst has excellent catalytic performance and good stability.

[0022] Currently, there are few studies on radiation-catalyzed hydrogen production, and there is no method specifically for irradiating in combination with a catalyst to produce hydrogen. The inventors of the present invention found that MoS₂ 2 / CeO₂ 2 heterojunction composite materials can be used as efficient catalysts for radiation hydrogen production, thereby effectively utilizing radiation energy to produce clean energy.

[0023] In order to provide a larger intimate contact area at the interface of the molybdenum disulfide / cerium oxide composite material to be more suitable for cooperation with ionizing radiation, the molybdenum disulfide / cerium oxide composite material may further conform to one or more of the following characteristics.

[0024] In one possible embodiment, based on the total weight of the molybdenum disulfide / cerium oxide composite material, the content of CeO₂ 2 is 0.5-8 wt% (such as 0.5 wt%, 1 wt%, 1.5 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 8 wt%), and the content of MoS₂ 2 is 92-99.5 wt% (such as 92 wt%, 95 wt%, 96 wt%, 97 wt%, 98 wt%, 98.5 wt%, 99 wt%, 99.5 wt%).

[0025] In one possible embodiment, based on the total weight of the molybdenum disulfide / cerium oxide composite material, the content of CeO₂ 2 is 0.1-10 wt%, and the content of MoS₂ 2 is 90-99.9 wt%.

[0026] In one possible embodiment, the MoS₂ 2 is flaky, and this two-dimensional structure can effectively accelerate the transfer and separation of carriers.

[0027] In one possible embodiment, the MoS₂ 2 has a nanoscale size.

[0028] In one possible embodiment, the width of the flaky MoS₂ 2 is 200-500 nm, preferably 200-300 nm, and the thickness is 10-100 nm, preferably 50-100 nm;

[0029] In one possible embodiment, the CeO₂ 2 is granular.

[0030] In one possible embodiment, the CeO₂2 The average particle size is 5 - 50 nm, preferably 10 - 50 nm.

[0031] In a preferred embodiment, the CeO 2 is uniformly loaded on the surface of the flaky MoS 2 The width of the flaky is preferably 200 - 500 nm, and the thickness is 10 - 50 nm.

[0032] In a preferred embodiment, the average particle size of the molybdenum disulfide / cerium oxide composite is 50 - 500 nm, preferably 100 - 300 nm.

[0033] In the present invention, the average particle size is obtained by transmission electron microscopy (TEM).

[0034] The present invention exemplarily Figure 1 lists a molybdenum disulfide / cerium oxide composite of the present invention, and CeO 2 nanoparticles are uniformly attached to the surface of the MoS 2 scaly nanosheets.

[0035] The second aspect of the present invention provides a method for preparing the molybdenum disulfide / cerium oxide composite described in the first aspect. The method includes: subjecting a suspension containing water, CeO 2 nanoparticles, a Mo source, and a reducing agent to a hydrothermal reaction.

[0036] In order to increase the excitation degree of electrons and holes at the contact interface of the molybdenum disulfide / cerium oxide composite and thus further improve the catalytic performance of the obtained composite catalyst and the hydrogen evolution efficiency of ionization irradiation hydrogen production, in a possible embodiment, the method further includes subjecting the material containing the molybdenum disulfide / cerium oxide composite obtained from the hydrothermal reaction to ionization irradiation treatment.

[0037] Preferably, the conditions of the ionization irradiation treatment include: the intensity is 1 kGy - 50 kGy, preferably 5 kGy - 50 kGy; the time is 0.1 - 3 h, preferably 0.5 - 3 h.

[0038] The inventors of the present invention found that the excitation degree of electrons and holes at the contact interface of the molybdenum disulfide / cerium oxide composite subjected to ionization irradiation treatment will be improved. When the composite is used for ionization irradiation catalytic hydrogen production, the molybdenum disulfide / cerium oxide composite excited by ionization irradiation can achieve better catalytic hydrogen evolution effect.

[0039] The hydrothermal reaction, namely the in-situ hydrothermal reaction, specifically refers to a chemical reaction carried out under high temperature and high pressure water. This reaction is usually carried out in a closed reactor, where the reactants are heated and pressurized in water to promote the reaction. This reaction is a green chemical method because it does not require the use of organic solvents or other harmful chemicals, and at the same time can achieve high reaction conversion rate and selectivity.

[0040] In a possible embodiment, the conditions of the hydrothermal reaction include: the temperature is 180°C - 250°C (such as 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, 240°C, 250°C), and the time is 24 - 48 h (such as 24 h, 36 h, 48 h).

[0041] The method further includes: the suspension composed of water, CeO 2 nanoparticles, Mo source and reducing agent is obtained by ultrasonic treatment of the mixture of water, CeO 2 nanoparticles, Mo source and reducing agent. The ultrasonic time is, for example, 10 - 40 min.

[0042] The hydrothermal reaction needs to be transferred to a closed autoclave reactor for carrying out.

[0043] In a possible embodiment, the Mo source is selected from one or more of Na 2 MoO 4 (hydrate), (NH 4 ) 2 MoO 4 , MoCl 5 .

[0044] In a possible embodiment, the reducing agent is selected from one or more of thiourea, NaHS, and L-cysteine.

[0045] The amounts of the CeO 2 nanoparticles and Mo source are such that the resulting CeO 2 and MoS 2 meet the limitations in the first aspect, which will not be elaborated here.

[0046] The CeO 2 nanoparticles can be obtained by commercial purchase or preparation.

[0047] In a possible embodiment, the CeO 2 nanoparticles are prepared by the following method: in water, a cerium source and a complexing agent are subjected to a first reaction, and the material obtained from the first reaction is subjected to a second reaction with a surfactant.

[0048] In a possible embodiment, the conditions for the first reaction include: the reaction temperature is 60°C - 100°C (for example: 60°C, 70°C, 80°C, 90°C, 100°C), and the reaction time is 5 - 7 h (for example: 5 h, 6 h, 7 h).

[0049] In a possible embodiment, the conditions for the second reaction include: the reaction temperature is 60°C - 100°C (for example: 60°C, 70°C, 80°C, 90°C, 100°C), and the reaction time is 1 - 3 h (for example: 1 h, 2 h, 3 h).

[0050] In a possible embodiment, the cerium source is selected from one or more of Ce(NO 3 ) 3 , CeCl 3 , Ce 2 (SO 4 ) 3 .

[0051] In a possible embodiment, the complexing agent is selected from one or more of ammonium chloride, ammonium hydroxide, ethylenediamine, ammonium acetate, triethylenetetramine, hexamethylenetetramine, and citric acid.

[0052] In a preferred embodiment, the complexing agent is a combination of citric acid and ethylenediamine in a weight ratio of 1:(2 - 5), which helps to form CeO 2 nanoparticles with more uniform particle size.

[0053] In a possible embodiment, the surfactant is selected from one or more of sodium dodecyl sulfate, sodium dodecylbenzenesulfonate, polyethylene glycol, and polyvinylpyrrolidone.

[0054] In a possible embodiment, the method further includes solid-liquid separation of the material obtained from the hydrothermal reaction, and washing (for example, washing 1 - 5 times with distilled water and then washing 1 - 5 times with ethanol) and drying (for example, drying in an oven at 80°C for 12 hours) of the obtained solid.

[0055] The product obtained in the second aspect of the present invention may be the same as the molybdenum disulfide / cerium oxide composite material described in the first aspect of the present invention, and will not be elaborated herein.

[0056] The third aspect of the present invention provides a hydrogen production method, which includes ionizing radiation of water or an organic solution in the presence of a catalyst, and the catalyst is the molybdenum disulfide / cerium oxide composite material of the first aspect of the present invention and / or the molybdenum disulfide / cerium oxide composite material prepared by the method of the second aspect.

[0057] In a possible implementation, relative to 1 kg of water to be treated, the dosage of the catalyst is 0.001 - 10 g, preferably 1 - 10 g.

[0058] In a possible implementation, relative to 1 g of the catalyst, the intensity of the ionizing radiation is 10 kGy - 1 MGy, preferably 50 kGy - 1 MGy; the time is 0.1 - 24 h, preferably 0.5 - 24 h.

[0059] The ionizing radiation can be selected from one or more of the radiation energy of nuclear waste, electron beam, neutron beam, gamma ray, X-ray, charged heavy ion beam, etc.

[0060] The specific heterojunction catalyst of the present invention can cooperate well with ionizing irradiation to achieve hydrogen production by irradiation, can utilize the dangerous and difficult-to-use energy of the radiation energy of nuclear waste, and produce clean energy, filling the gap in the prior art in the method of hydrogen production by irradiation in cooperation with a catalyst. The molybdenum disulfide / cerium oxide composite heterojunction catalyst of the present invention has excellent catalytic performance and stability, can be recycled, and the hydrogen evolution efficiency of the hydrogen production method of the present invention is high, further promoting the industrialization process of catalytic water hydrogen evolution.

[0061] Next, the technical solutions in the embodiments of the present application will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0062] Unless otherwise specified, the experimental methods used in the following examples are all conventional methods; the reagents, materials, etc. used in the following examples can be obtained from commercial channels unless otherwise specified.

[0063] The following Group A embodiments are used to illustrate MoS 2 / CeO 2 Composite materials and their preparation methods

[0064] Example A1 group

[0065] (1) Preparation of CeO 2 nanoparticles

[0066] ① Mix a solution containing 5 mL of a citric acid and ethylenediamine mixture (0.51 g of citric acid and 1.02 g of ethylenediamine), 100 mL of deionized water, and 100 mL of Ce(NO 3 ) 3 ·6H 2The mixed solution containing 2.17 g of O solution was placed in a round-bottom flask and heated to 80 °C for 6 h.

[0067] ② 50 mL of sodium dodecyl sulfate (SDS) solution (containing 1.46 g) was further added to the above mixed solution and heated for another 2 h.

[0068] ③ After the above reaction was completed, the reaction product was precipitated by centrifugation and washed 3 times with distilled water, and then washed 1 time with ethanol. The obtained white powder was dried in vacuo at room temperature to obtain CeO 2 particles, and the average particle size was measured to be 30 nm.

[0069] (2) Preparation of MoS 2 / CeO 2 Composite material

[0070] ① The CeO 2 prepared above was dispersed in 60 mL of an aqueous solution composed of 1 mmol (0.007 g) of Na 2 MoO 4 ·2H 2 O and 5 mmol (0.0115 g) of thiourea, and ultrasonic treatment was carried out for about 30 min.

[0071] ② The homogeneous mixture suspension obtained in step ① was transferred to a 100 mL Teflon-lined stainless steel autoclave and maintained in an electric furnace at 210 °C for 24 h.

[0072] ③ After natural cooling to room temperature, the obtained precipitate was separated by centrifugation, thoroughly washed 3 times with distilled water, then washed 1 time with ethanol, and dried in an oven at 80 °C for 12 h.

[0073] (3) Ionizing irradiation treatment

[0074] The dried MoS 2 / CeO 2 nano-composite material was placed in an irradiation chamber, and the MoS 2 / CeO 2 nano-composite material was irradiated by the irradiation energy of nuclear waste, the irradiation intensity was 50 kGy, and the irradiation time was 2 h.

[0075] Finally, the MoS 2 / CeO 2 composite material was denoted as H1. The average particle size was measured to be 300 nm.

[0076] After testing, the weight percentage of CeO 2 in the obtained H1 was 2 wt%, and the weight percentage of MoS 2 was 98 wt%.

[0077] The obtained H1 was subjected to TEM scanning as Figure 1 shown.

[0078] Example A2 group

[0079] This group of examples is used to illustrate the different ratios of MoS 2 / CeO 2 in the composite material. 2 and CeO 2 in the MoS

[0080] This group of examples was carried out with reference to Example 1. The difference is that the dosage of CeO 2 and / or the Mo source was changed, so that the weight percentage of CeO 2 in the obtained MoS 2 / CeO 2 composite material was respectively (the weight percentage of MoS 2 was 100% minus the weight percentage of CeO 2 , which will not be listed separately here):

[0081] Example A2a, the weight percentage of CeO 2 was 1%, and the obtained MoS 2 / CeO 2 composite material was denoted as H2a;

[0082] Example A2b, the weight percentage of CeO 2 was 4%, and the obtained MoS 2 / CeO 2 composite material was denoted as H2b;

[0083] Example A2c, the weight percentage of CeO 2 was 0.5%, and the obtained MoS 2 / CeO 2 composite material was denoted as H2c;

[0084] Example A2d, the weight percentage of CeO 2 was 8%, and the obtained MoS 2 / CeO 2 composite material was denoted as H2d.

[0085] Example A3 group

[0086] This group of examples is used to illustrate the influence of the size of the MoS 2 / CeO 2 composite material on the effect.

[0087] This group of examples was carried out with reference to Example 1. The difference is that commercially available CeO 2Powders with different particle sizes (constant weight), specifically:

[0088] Example A3a, using CeO with an average particle size of 50 nm 2 , and the resulting MoS 2 / CeO 2 composite material is denoted as H3a;

[0089] Example A3b, using CeO with an average particle size of 5 nm 2 , and the resulting MoS 2 / CeO 2 composite material is denoted as H3b.

[0090] Example A4 group

[0091] This group of examples is used to illustrate the influence of the preparation method of CeO 2 nanoparticles on the effect.

[0092] This group of examples is carried out with reference to Example 1, except that the preparation method of CeO 2 nanoparticles is changed, specifically:

[0093] Example A4a, where the 5 mL mixed solution of citric acid and ethylenediamine in the complex is replaced with 5 mL citric acid (containing 1.53 g), and the resulting MoS 2 / CeO 2 composite material is denoted as H4a.

[0094] Example A4b, where the 5 mL mixed solution of citric acid and ethylenediamine in the complex is replaced with 5 mL hexamethylenetetramine (HMT) solution (containing 1.42 g), and the resulting MoS2 / CeO2 composite material is denoted as H4b.

[0095] Example A5 group

[0096] This group of examples is used to illustrate the influence of the ionization irradiation treatment step on the effect.

[0097] This group of examples is carried out with reference to Example 1, except that the ionization irradiation treatment in step (3) is changed, specifically:

[0098] Example A5a, without setting this step, and the MoS 2 / CeO 2 composite material obtained after drying in step (2) is denoted as H5a;

[0099] Example A5b, changing the conditions of ionization irradiation, with an irradiation intensity of 0.5 kGy and an irradiation time of 0.5 h, and the MoS 2 / CeO 2 composite material after ionization irradiation treatment is denoted as H5b;

[0100] Example A5c, the conditions of ionizing irradiation were changed. The irradiation intensity was 100 kGy and the irradiation time was 3 h. The MoS 2 / CeO 2 composite material was denoted as H5c.

[0101] The following Group B examples are used to illustrate the hydrogen production method of the present invention.

[0102] Example B1

[0103] Taking the MoS 2 / CeO 2 composite material prepared in Example A1 as a catalyst, in cooperation with ionizing irradiation, water was catalytically decomposed to produce hydrogen. Specifically:

[0104] 1 g of MoS 2 / CeO 2 nano-composite material was placed in the irradiation chamber. The irradiation chamber was filled with 1 kg of water. The MoS 2 / CeO 2 nano-composite material was irradiated with the irradiation energy of nuclear waste. The irradiation intensity was 50 kGy and the irradiation time was 1 h. Hydrogen was obtained and the hydrogen production amount was collected and recorded.

[0105] Examples B2 to B5 were carried out respectively according to Example B1. The difference was that the MoS 2 / CeO 2 composite material was replaced with A2 to A5 in the same weight parts.

[0106] Example B6 group

[0107] This group of examples is used to illustrate the influence of the conditions of irradiation hydrogen production on the effect.

[0108] This group of examples was carried out with reference to Example B1. The difference was:

[0109] Example B6a, the amount of MoS 2 / CeO 2 nano-composite material was changed to 0.1 g;

[0110] Example B6b, the amount of MoS 2 / CeO 2 nano-composite material was changed to 10 g;

[0111] Example B6c, the irradiation conditions were changed so that the irradiation intensity was 10 kGy and the irradiation time was 1 h;

[0112] Example B6d, the irradiation conditions were changed so that the irradiation intensity was 1 MGy and the irradiation time was 1 h; Comparative Example 1

[0113] This was carried out with reference to Example 1, except that the dosage of CeO 2 and / or the Mo source was changed such that the weight percentage of CeO 2 in the obtained MoS 2 / CeO 2 composite material was 15 wt%, and the weight percentage of MoS 2 was 85 wt%.

[0114] Comparative Example 2

[0115] This was carried out with reference to Example 1, except that CeO 2 was replaced with TiO 2 of the same weight.

[0116] Comparative Example 3

[0117] This was carried out with reference to Example 1, except that MoS 2 was replaced with graphene of the same weight.

[0118] The hydrogen production amount (mL) and hydrogen production rate (mL / min) obtained in each example were recorded and calculated, and the results were recorded in Table 1.

[0119] Table 1

[0120]

[0121]

[0122] As can be seen from Table 1, under the same irradiation intensity of 100 kGy, the hydrogen production effect of using the H1 composite material as a catalyst was the best, with a hydrogen production amount of 2464 mL and a rate of 41 mL / min. The content, particle size, preparation method, and irradiation conditions of CeO 2 had a significant impact on the performance. An appropriate content or optimized particle size (such as 1% or 50 nm) improved the performance, while an unreasonable preparation method or non-irradiation treatment significantly reduced the performance. In the comparative examples, a high CeO 2 content (15%), replacing CeO 2 or MoS 2 materials both led to a decrease in performance, indicating that optimizing the characteristics of CeO 2 and the irradiation conditions are the key to improving the catalytic hydrogen production efficiency.

[0123] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, including any other suitable combination of each technical feature. These simple modifications and combinations should also be regarded as the content disclosed by the present invention and fall within the protection scope of the present invention.

Claims

1. A molybdenum disulfide / cerium oxide composite material, characterized in that: The composite material comprises MoS2 and CeO2 loaded on the surface of the MoS2. Based on the total weight of the molybdenum disulfide / cerium oxide composite material, the content of CeO2 is 0.1-10 weight percent, and the content of MoS2 is 90-99.9 weight percent.

2. The molybdenum disulfide / cerium oxide composite material according to claim 1, wherein: Based on the total weight of the molybdenum disulfide / cerium oxide composite material, the content of CeO2 is 0.5-8 weight %, and the content of MoS2 is 92-99.5 weight %; Preferably, based on the total weight of the molybdenum disulfide / cerium oxide composite material, the content of CeO2 is 1-4% by weight, and the content of MoS2 is 96-99% by weight.

3. The molybdenum disulfide / cerium oxide composite material according to claim 1 or 2, wherein: The average particle size of the molybdenum disulfide / cerium oxide composite material is 50-500nm, preferably 100-300nm; And / or, the MoS2 is in a scale shape, preferably the scale width is 200-500nm, and the thickness is 10-50nm; And / or, the CeO2 is in granular form, preferably with a particle size of 5-50 nm.

4. A method for preparing the molybdenum disulfide / cerium oxide composite material according to any one of claims 1 to 3, the method comprising: A suspension containing water, CeO2 nanoparticles, a Mo source and a reducing agent is subjected to a hydrothermal reaction.

5. The method according to claim 4, wherein: The method further comprises subjecting the material containing the molybdenum disulfide / cerium oxide composite material obtained by the hydrothermal reaction to ionizing radiation treatment; Preferably, the conditions of the ionizing radiation treatment include: an intensity of 1-50 kGy and a time of 0.1-3 h.

6. The method according to claim 4 or 5, wherein: The conditions of the hydrothermal reaction include: temperature of 180° C.-250° C. and time of 24-48 hours.

7. The method according to claim 4 or 5, wherein: The CeO2 nanoparticles are prepared by the following method: in water, a cerium source and a complexing agent are subjected to a first reaction, and a material obtained by the first reaction is subjected to a second reaction with a surfactant; Preferably, the conditions of the first reaction include: reaction temperature of 60-100°C, reaction time of 5-7h; Preferably, the conditions of the second reaction include: reaction temperature of 60-100° C., and reaction time of 1-3 h.

8. The method according to claim 7, wherein: The cerium source is selected from one or more of Ce(NO3)3, CeCl3, and Ce2(SO4)3; and / or, the complexing agent is selected from one or more of ammonium chloride, ammonium hydroxide, ethylenediamine, ammonium acetate, triethylenetetramine, hexamethylenetetramine, and citric acid; And / or, the surfactant is selected from one or more of sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, polyethylene glycol, and polyvinyl pyrrolidone.

9. A method for producing hydrogen, characterized in that: The hydrogen production method comprises ionizing radiation to water or an organic solution in the presence of a catalyst; wherein the catalyst is the molybdenum disulfide / cerium oxide composite material described in any one of claims 1 to 3 and / or the molybdenum disulfide / cerium oxide composite material prepared by the method described in any one of claims 4 to 8.

10. The method for producing hydrogen according to claim 9, wherein: Relative to 1 kg of water to be treated, the amount of the catalyst used is 0.001-10 g; The intensity of the ionizing radiation is 10 kGy-1 MGy, and the time is 0.1-24 h; And / or, the ionizing radiation is selected from one or more of the radiation energy of nuclear waste, electron beam, neutron beam, gamma ray, X-ray, and charged heavy ion beam.

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