A method for synthesizing Mn 0.43 Cd 0.57 A method for synthesizing a S / Cu2MoS4 photocatalyst

Abstract

This invention discloses a method for synthesizing Mn using a solvothermal method. 0.43 Cd 0.57 This invention relates to a method for producing S / Cu2MoS4 photocatalysts, belonging to the field of catalyst technology. First, copper molybdenum sulfide is prepared using cuprous oxide as a template. A solvothermal method is then used to synthesize copper molybdenum sulfide with high purity and good crystallinity. Next, manganese cadmium sulfide is prepared using manganese acetate, cadmium acetate, sodium hydroxide, and thioacetamide as raw materials. Before the hydrothermal reaction, copper molybdenum sulfide is added, and manganese cadmium sulfide is successfully modified by constructing a heterojunction, thus synthesizing Mn. 0.43 Cd 0.57 The S / Cu2MoS4 photocatalyst improved the photocatalytic hydrogen production rate of manganese cadmium sulfide. Furthermore, the Mn prepared in this invention... 0.43 Cd 0.57 The S / Cu2MoS4 photocatalyst can produce hydrogen at a rate of 8233 μmol / (g·h), which is 2.08 times that of pure manganese cadmium sulfide and 1.24 times that of manganese cadmium sulfide loaded with 1% platinum.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of catalysts, and particularly relates to a method for synthesizing a Mn 0.43 Cd 0.57 S / Cu2MoS4 photocatalyst by a solvothermal method. BACKGROUND

[0002] Hydrogen energy is known for its clean and efficient nature, and plays a crucial role in promoting global carbon neutralization and sustainable development. Photocatalytic hydrogen evolution is a common method for hydrogen production, and photocatalysts are the key to affecting the efficiency of photocatalytic reactions. The photocatalytic process involves the following steps: (1) light absorption and excitation: the photocatalyst absorbs light, causing the valence band electrons to jump, thereby generating photo-generated carriers (electrons-holes). (2) separation, migration and recombination of photo-generated carriers: a part of the photo-generated carriers recombine in the bulk or on the surface, and finally convert into light or heat, which is useless for photocatalytic reactions and is considered as ineffective carriers; a part of the photo-generated carriers separate and migrate to the surface of the photocatalyst to undergo an oxygen reduction reaction and are considered as effective carriers. (3) surface oxidation-reduction reaction: the effective carriers undergo a reduction reaction on the surface to reduce water into hydrogen, and the oxidation reaction that occurs can be used to degrade organic pollutants or oxidize water into oxygen. Among various photocatalysts that have been studied, the photocatalytic reaction efficiency is relatively low due to reasons such as fast recombination of photo-generated carriers and low adsorption capacity for reactants, which means that more energy is needed to produce the same amount of hydrogen, limiting the industrialization and application of photocatalytic hydrogen evolution technology, and therefore designing an efficient photocatalyst is particularly crucial for the industrialization and application of photocatalytic hydrogen evolution technology.

[0003] Solvothermal synthesis is one of the common methods for preparing photocatalysts and other catalysts and materials, and solvothermal reaction has the advantages of mild conditions, simple operation, uniform mixing of reactants in the solvent, fast chemical reaction speed, easy ion stoichiometric reaction, grain growth according to its crystallization habit, self-removal of impurities to the solvent during the reaction process, and high product purity. As a photocatalyst, cadmium manganese sulfide has certain photocatalytic performance, but the fast recombination of photo-generated carriers reduces its photocatalytic reaction rate. Therefore, how to modify the cadmium manganese sulfide photocatalyst by solvothermal synthesis to improve the effective separation and migration of photo-generated carriers of the catalyst and thus improve its photocatalytic performance has become a technical problem that needs to be solved in the field. SUMMARY

[0004] To solve the above technical problems, the application provides a method for synthesizing a Mn 0.43 Cd 0.57 S / Cu2MoS4 photocatalyst by a solvothermal method, so as to solve the problem of low photocatalytic reaction rate caused by the fast recombination of photo-generated carriers of the existing photocatalyst material.

[0005] To achieve the above object, the present application provides the following technical solutions.

[0006] The present application provides a kind of synthesis Mn 0.43 Cd 0.57 S / Cu2MoS4 Photocatalyst method, comprising the following steps:

[0007] (1) cuprous oxide is dispersed in ethylene glycol, then sodium molybdate and thioacetamide are added to carry out solvothermal reaction, to obtain molybdenum copper sulfide;

[0008] (2) manganese acetate, cadmium acetate and sodium hydroxide are mixed to carry out displacement reaction, then thioacetamide and the molybdenum copper sulfide of step (1) are added to carry out hydrothermal reaction, to obtain the Mn 0.43 Cd 0.57 S / Cu2MoS4 Photocatalyst.

[0009] Technical principle:

[0010] The present application first prepares molybdenum copper sulfide with cuprous oxide as template, combines solvothermal method, and the prepared molybdenum copper sulfide has high purity and good crystallinity, then uses manganese acetate, cadmium acetate, sodium hydroxide and thioacetamide as raw materials to prepare cadmium manganese sulfide (Mn 0.43 Cd 0.57 S), and the above molybdenum copper sulfide is added before hydrothermal reaction, the cadmium manganese sulfide is successfully modified by constructing heterojunction, and the Mn 0.43 Cd 0.57 S / Cu2MoS4) photocatalyst is successfully synthesized, and the photocatalytic hydrogen production rate of cadmium manganese sulfide is improved.

[0011] Further, in step (1), the molar ratio of cuprous oxide, sodium molybdate and thioacetamide is 0.16:0.19:1.

[0012] Further, in step (1), the temperature of solvothermal reaction is 160 DEG C, and the time is 12h.

[0013] Further, in step (1), the preparation method of cuprous oxide comprises the following steps: copper sulfate, sodium citrate and sodium hydroxide are mixed to carry out double decomposition reaction, then ascorbic acid aqueous solution is added to carry out redox reaction, to obtain the cuprous oxide.

[0014] Further, the molar ratio of copper sulfate, sodium citrate and sodium hydroxide is 0.06:0.017:1, and the molar ratio of copper sulfate and ascorbic acid in the ascorbic acid aqueous solution is 1:1.

[0015] Further, in step (2), the manganese acetate is tetrahydrate manganese acetate, and the cadmium acetate is dihydrate cadmium acetate.

[0016] Further, in step (2), the molar ratio of manganese acetate tetrahydrate, cadmium acetate dihydrate and sodium hydroxide is 1:1:8; the molar ratio of manganese acetate tetrahydrate and thioacetamide is 1:4.

[0017] Furthermore, in step (2), the hydrothermal reaction is carried out at a temperature of 180°C for 18 hours.

[0018] Furthermore, in step (2), the mass of the added copper molybdenum sulfide is 1 wt% to 5 wt% of the mass of the manganese cadmium sulfide synthesized by the hydrothermal reaction.

[0019] The present invention also provides Mn prepared by the method described in the above technical solution. 0.43 Cd 0.57 S / Cu2MoS4 photocatalyst.

[0020] Compared with the prior art, the present invention has the following advantages and technical effects:

[0021] This invention successfully synthesized high-purity, well-crystallized manganese cadmium sulfide / copper molybdenum sulfide (Mn) using a solvothermal method. 0.43 Cd 0.57 S / Cu2MoS4) photocatalyst; cadmium sulfide manganese (Mn) was successfully modified by constructing a heterojunction. 0.43 Cd 0.57 S), which greatly improves its photocatalytic hydrogen production rate, provides a new pathway for modifying existing photocatalysts and hydrogen production; the composite of manganese cadmium sulfide and non-precious metal copper molybdenum sulfide saves costs while significantly improving the hydrogen production rate of the photocatalyst, Mn 0.43 Cd 0.57 The hydrogen production rate of the S / Cu2MoS4 photocatalyst can reach a higher rate than that of hydrogen production rate of platinum supported on cadmium sulfide manganese. Attached Figure Description

[0022] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0023] Figure 1 This invention provides a method for synthesizing Mn using a solvothermal method. 0.43 Cd 0.57 Schematic diagram of the reaction process of the S / Cu2MoS4 photocatalyst method;

[0024] Figure 2 This invention provides a method for synthesizing Mn using a solvothermal method. 0.43 Cd 0.57 Process flow diagram of the method for S / Cu2MoS4 photocatalyst;

[0025] Figure 3 Mn prepared for Examples 1-3 and Comparative Examples 1, 3-4 0.43 Cd 0.57 XRD patterns of S / Cu2MoS4 photocatalyst, molybdenum sulfide copper prepared in step (2) of Example 1, pure cadmium manganese sulfide prepared in Comparative Example 2;

[0026] Figure 4 Mn prepared for Examples 1-3 and Comparative Examples 1, 3-4 0.43 Cd 0.57 XRD patterns of S / Cu2MoS4 photocatalyst, pure cadmium manganese sulfide prepared in Comparative Example 2, and 1% Pt / Mn prepared in Comparative Example 5 0.43 Cd 0.57 Comparison chart of photocatalytic hydrogen evolution rate of S

[0027] Figure 5 Mn prepared for Examples 1-3 and Comparative Example 1 0.43 Cd 0.57 Electrochemical test chart of S / Cu2MoS4 photocatalyst, molybdenum sulfide copper prepared in step (2) of Example 1, pure cadmium manganese sulfide prepared in Comparative Example 2, wherein A is the electrochemical impedance test result chart, B is the transient photocurrent response test result chart, C is the open circuit voltage decay curve chart, and D is the linear sweep voltammetry test result chart. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be apparently and completely described below with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative labor fall within the protection scope of the present application.

[0029] In order to make the above objectives, characteristics and advantages of the present application more apparent and easy to understand, the present application will be further described in detail below with the accompanying drawings and specific embodiments.

[0030] The embodiments of the present application provide a method for synthesizing Mn 0.43 Cd 0.57 The method for synthesizing S / Cu2MoS4 photocatalyst comprises the following steps:

[0031] (1) dispersing cuprous oxide in ethylene glycol, then adding sodium molybdate and thioacetamide to perform a solvothermal reaction to obtain molybdenum sulfide copper;

[0032] (2) mixing manganese acetate, cadmium acetate and sodium hydroxide to perform a displacement reaction, then adding thioacetamide and the molybdenum sulfide copper in step (1) to perform a hydrothermal reaction to obtain the Mn0.43 Cd 0.57 S / Cu2MoS4 photocatalyst.

[0033] In the preferred embodiment, in step (1), the preparation method of the cuprous oxide comprises the following steps: mixing copper sulfate, sodium citrate and sodium hydroxide to carry out a double decomposition reaction, and then adding an ascorbic acid aqueous solution to carry out a redox reaction, so as to obtain the cuprous oxide. The cupric hydroxide is prepared by taking copper sulfate, sodium citrate and sodium hydroxide as reactants, and then the cuprous oxide is prepared by reducing the cupric hydroxide by using ascorbic acid as a reducing agent; the sodium citrate can prevent the oxidation of copper ions, thereby improving the purity of the cupric hydroxide; and the use of ascorbic acid as a reducing agent has the advantages of environmental protection, mildness, controllability and low cost.

[0034] In the preferred embodiment, in the process of preparing the cuprous oxide, the following reaction occurs:

[0035] CuSO4+2NaOH=Cu(OH)2↓+Na2SO4

[0036] 2Cu(OH)2+C6H8O6=Cu2O+3H2O+C6H6O6.

[0037] In the preferred embodiment, the molar ratio of the copper sulfate, the sodium citrate and the sodium hydroxide is 0.06:0.017:1; and the molar ratio of the copper sulfate to the ascorbic acid in the ascorbic acid aqueous solution is 1:1. The use amount of the above reactants is strictly controlled in the present application, so as to avoid the generation of by-products or other impurities due to side reactions.

[0038] In the preferred embodiment, in step (1), in the process of preparing the copper molybdenum sulfide, the following reaction occurs:

[0039] Cu2O+Na2MoO4+4C2H5NS+C2H6O2

[0040] =Cu2MoS4+4C2H5NO+2NaOH+C2H4O

[0041] In the preferred embodiment, in step (1), the molar ratio of the cuprous oxide, the sodium molybdate and the thioacetamide is 0.16:0.19:1. The use amount of the above reactants is strictly controlled in the present application, so as to avoid the generation of by-products or other impurities due to side reactions.

[0042] In the preferred embodiment, in step (1), the temperature of the solvothermal reaction is 160°C, and the time is 12h. The solvothermal method is used to prepare the copper molybdenum sulfide in the present application, and the method has the advantages of high purity of the product, good crystallinity and easy control of particle size.

[0043] In a preferred embodiment, in step (2), the manganese acetate is manganese acetate tetrahydrate, and the cadmium acetate is cadmium acetate dihydrate.

[0044] In a preferred embodiment, in step (2), the molar ratio of the manganese acetate tetrahydrate, the cadmium acetate dihydrate and the sodium hydroxide is 1:1:8; and the molar ratio of the manganese acetate tetrahydrate and the thioacetamide is 1:4.

[0045] In a preferred embodiment, in step (2), the manganese acetate, the cadmium acetate, the sodium hydroxide and the thioacetamide react to form the cadmium manganese sulfide as follows:

[0046] 0.43Mn(CH3COO)2+0.57Cd(CH3COO)2+2NaOH+C2H5NS

[0047] =2CH3COONa+Mn 0.43 Cd 0.57 S+C2H5NO+H2O.

[0048] In a preferred embodiment, in step (2), the temperature of the hydrothermal reaction is 180℃, and the time is 18h.

[0049] In a preferred embodiment, in step (2), the mass of the copper molybdenum sulfide added is 1wt% to 5wt% of the mass of the cadmium manganese sulfide synthesized by the hydrothermal reaction, and is further preferably 1wt% to 3wt%. The mass of the copper molybdenum sulfide added is controlled within the above range, which is advantageous to obtain the Mn 0.43 Cd 0.57 S / Cu2MoS4photocatalyst.

[0050] The application also provides the Mn 0.43 Cd 0.57 S / Cu2MoS4photocatalyst prepared by the method.

[0051] Unless otherwise specified, the raw materials in the embodiments of the application are obtained by commercial purchase.

[0052] Embodiment 1

[0053] A method for synthesizing a Mn 0.43 Cd 0.57 S / Cu2MoS4photocatalyst by a solvothermal method, the specific steps are as follows, and a process flow chart is shown in Figure 2 :

[0054] (1) Copper sulfate, sodium citrate, sodium hydroxide with a molar ratio of 0.06:0.017:1 were mixed to carry out a metathesis reaction, after sufficient reaction, an ascorbic acid aqueous solution was added to carry out a redox reaction, after sufficient reaction, Cu2O was prepared by standing, washing, vacuum drying and grinding; wherein the molar ratio of copper sulfate to ascorbic acid in the ascorbic acid aqueous solution was 1:1.

[0055] (2) Cu2O obtained in step (1) was dispersed into ethylene glycol, then sodium molybdate and thioacetamide were added, and a solvothermal reaction was carried out at 160°C, the reaction was completed after 12h, and after washing, vacuum drying and grinding, Cu2MoS4 was prepared; wherein the molar ratio of Cu2O, sodium molybdate and thioacetamide was 0.16:0.19:1.

[0056] (3) Manganese acetate tetrahydrate, cadmium acetate dihydrate and sodium hydroxide with a molar ratio of 1:1:8 were mixed and fully reacted, then thioacetamide and Cu2MoS4 obtained in step (2) were fully mixed, and a hydrothermal reaction was carried out at 180°C (the molar ratio of manganese acetate tetrahydrate to thioacetamide was 1:4, and the mass of Cu2MoS4 added was 1wt% of the mass of the synthesized CdMnS), the reaction was completed after 18h, and after washing, vacuum drying and grinding, Mn 0.43 Cd 0.57 S / 1%Cu2MoS4 photocatalyst was obtained.

[0057] Example 2

[0058] The difference from Example 1 is only that in step (3), the mass of Cu2MoS4 added is 3wt% of the mass of the hydrothermally synthesized CdMnS, and Mn 0.43 Cd 0.57 S / 3%Cu2MoS4 photocatalyst was obtained.

[0059] Example 3

[0060] The difference from Example 1 is only that in step (3), the mass of Cu2MoS4 added is 5wt% of the mass of the hydrothermally synthesized CdMnS, and Mn 0.43 Cd 0.57 S / 5%Cu2MoS4 photocatalyst was obtained.

[0061] Comparative Example 1

[0062] The difference from Example 1 is only that in step (3), the mass of Cu2MoS4 added is 7wt% of the mass of the hydrothermally synthesized CdMnS, and Mn 0.43 Cd 0.57 S / 7%Cu2MoS4 photocatalyst was obtained.

[0063] Comparative Example 2

[0064] A method for preparing pure cadmium manganese sulfide, the specific steps are as follows:

[0065] Manganese acetate tetrahydrate, cadmium acetate dihydrate and sodium hydroxide with a molar ratio of 1:1:8 were mixed and fully reacted, then thioacetamide was added, fully mixed, and then subjected to hydrothermal reaction at 180°C (the molar ratio of manganese acetate tetrahydrate to thioacetamide was 1:4), and the reaction was ended after 18 hours, followed by washing, vacuum drying, and grinding to prepare cadmium manganese sulfide Mn 0.43 Cd 0.57 S photocatalyst.

[0066] Comparative Example 3

[0067] The difference from Example 1 is that step (3) is: manganese acetate tetrahydrate, cadmium acetate dihydrate and sodium hydroxide with a molar ratio of 1:1:8 were mixed and fully reacted, then thioacetamide was added (the molar ratio of manganese acetate tetrahydrate to thioacetamide was 1:4), fully mixed, and then subjected to hydrothermal reaction at 180°C, and the reaction was ended after 18 hours, then copper molybdenum sulfide obtained in step (2) was added (the mass of the added copper molybdenum sulfide was 1wt% of the mass of the cadmium manganese sulfide synthesized by hydrothermal reaction), fully mixed, and then subjected to hydrothermal reaction at 180°C, and the reaction was ended after 18 hours, followed by washing, vacuum drying, and grinding to prepare cadmium manganese sulfide / copper molybdenum sulfide photocatalyst.

[0068] Comparative Example 4

[0069] The difference from Example 1 is that in step (3), the mass of the added copper molybdenum sulfide was 20wt% of the mass of the cadmium manganese sulfide synthesized by hydrothermal reaction, and the others were the same as Example 1.

[0070] Comparative Example 5

[0071] Mn 0.43 Cd 0.57 S loaded with 1% Pt was synthesized by a thermal in-situ deposition method, and the specific steps are as follows: first, 200mg of pure cadmium manganese sulfide prepared in Comparative Example 2 was uniformly dispersed in 5.4mL of 1.91mM chloroplatinic acid (H2PtCl6·H2O) solution. Then, the water was evaporated to make the sample present a sol-like state under the condition of water bath at 80°C, and then the sample was dried in an oven at 80°C, and then the obtained sample was dispersed in ethylene glycol and subjected to water bath at 100°C for 30min. After the reaction was completed, the sample was collected by centrifugation and washed with deionized water and ethanol for several times, and then the sample was vacuum dried at 80°C to prepare cadmium manganese sulfide loaded with platinum (1% Pt / Mn 0.43 Cd 0.57 S).

[0072] Figure 1 A method for synthesizing Mn0.43 Cd 0.57 Schematic diagram of the reaction process of the S / Cu2MoS4 photocatalyst method.

[0073] Figure 2 This invention provides a method for synthesizing Mn using a solvothermal method. 0.43 Cd 0.57 A process flow diagram for the S / Cu2MoS4 photocatalyst method. (From...) Figure 2 As can be seen, this invention first prepares Cu2O nanocubes using CuSO4, NaOH, and ascorbic acid as raw materials. Then, the obtained Cu2O is mixed with thioacetamide and Na2MoO4 for a solvothermal reaction to obtain Cu2MoS4 nanosheets. Next, Mn(CH3COO)2, Cd(CH3COO)2, and NaOH are mixed and reacted. Then, thioacetamide and Cu2MoS4 are added for a hydrothermal reaction to obtain Mn 0.43 Cd 0.57 S / Cu2MoS4 complex.

[0074] Figure 3 Mn prepared for Examples 1-3 and Comparative Examples 1 and 3-4 0.43 Cd 0.57 XRD patterns of S / Cu2MoS4 photocatalyst, copper molybdenum sulfide prepared in step (2) of Example 1, and pure manganese cadmium sulfide prepared in Comparative Example 2. Figure 3 As can be seen, all diffraction peaks correspond to the standard data card, and there are no additional diffraction peaks, indicating that pure manganese cadmium sulfide, pure copper molybdenum sulfide, and a series of Mn were successfully prepared. 0.43 Cd 0.57 S / Cu2MoS4 photocatalyst.

[0075] Figure 4 Mn prepared for Examples 1-3 and Comparative Examples 1 and 3-4 0.43 Cd 0.57 S / Cu2MoS4 photocatalyst, pure cadmium manganese sulfide prepared in Comparative Example 2, and 1% Pt / Mn prepared in Comparative Example 5 0.43 Cd 0.57 A comparison of the photocatalytic hydrogen evolution rates of S. From Figure 4 It can be seen that the hydrogen production rate of pure cadmium sulfide manganese is 3950 μmol / (g·h), and the 1% Pt / Mn ratio is... 0.43 Cd 0.57 The hydrogen production rate of S is 6639 μmol / (g·h); in Example 1, Mn 0.43 Cd 0.57 The hydrogen production rate of the S / 1% Cu2MoS4 photocatalyst was 7189 μmol / (g·h), which was 1.82 times that of pure cadmium sulfide manganese hydrogen production; in Example 2, Mn0.43 Cd 0.57 S / 3%Cu2MoS4 photocatalyst was 8233 μmol / (g·h), which was 2.08 times of the hydrogen production rate of pure Cd2MnS, and the Cd2MnS / Cu2MoS4 photocatalyst in this proportion showed the optimal hydrogen production performance, which was 1%Pt / Mn 0.43 Cd 0.57 S / 3%Cu2MoS4 photocatalyst was 8233 μmol / (g·h), which was 2.08 times of the hydrogen production rate of pure Cd2MnS, and the Cd2MnS / Cu2MoS4 photocatalyst in this proportion showed the optimal hydrogen production performance, which was 1%Pt / Mn 0.43 Cd 0.57 S / 3%Cu2MoS4 photocatalyst was 8233 μmol / (g·h), which was 2.08 times of the hydrogen production rate of pure Cd2MnS, and the Cd2MnS / Cu2MoS4 photocatalyst in this proportion showed the optimal hydrogen production performance, which was 1%Pt / Mn 0.43 Cd 0.57 S / 3%Cu2MoS4 photocatalyst was 8233 μmol / (g·h), which was 2.08 times of the hydrogen production rate of pure Cd2MnS, and the Cd2MnS / Cu2MoS4 photocatalyst in this proportion showed the optimal hydrogen production performance, which was 1%Pt / Mn 0.43 Cd 0.57 S / 3%Cu2MoS4 photocatalyst was 8233 μmol / (g·h), which was 2.08 times of the hydrogen production rate of pure Cd2MnS, and the Cd2MnS / Cu2MoS4 photocatalyst in this proportion showed the optimal hydrogen production performance, which was 1%Pt / Mn 0.43 Cd 0.57 S / 3%Cu2MoS4 photocatalyst was 8233 μmol / (g·h), which was 2.08 times of the hydrogen production rate of pure Cd2MnS, and the Cd2MnS / Cu2MoS4 photocatalyst in this proportion showed the optimal hydrogen production performance, which was 1%Pt / Mn 0.43 Cd 0.57 S / 3%Cu2MoS4 photocatalyst was 8233 μmol / (g·h), which was 2.08 times of the hydrogen production rate of pure Cd2MnS, and the Cd2MnS / Cu2MoS4 photocatalyst in this proportion showed the optimal hydrogen production performance, which was 1%Pt / Mn 0.43 Cd 0.57 S / 3%Cu2MoS4 photocatalyst was 8233 μmol / (g·h), which was 2.08 times of the hydrogen production rate of pure Cd2MnS, and the Cd2MnS / Cu2MoS4 photocatalyst in this proportion showed the optimal hydrogen production performance, which was 1%Pt / Mn

[0076] Figure 5 Mn prepared in Example 1-3 and Comparative Example 1 0.43 Cd 0.57 S / 3%Cu2MoS4 photocatalyst was 8233 μmol / (g·h), which was 2.08 times of the hydrogen production rate of pure Cd2MnS, and the Cd2MnS / Cu2MoS4 photocatalyst in this proportion showed the optimal hydrogen production performance, which was 1%Pt / Mn Figure 5 A can be seen, compared with other samples, Mn 0.43 Cd 0.57 S / 3%Cu2MoS4 (Example 2) has the smallest electrochemical impedance value, indicating that it has the strongest ability to promote carrier migration and separation; in Figure 5 B, Mn 0.43 Cd 0.57The photocurrent intensity of S / 3%Cu2MoS4 is obviously stronger than other samples, indicating that the charge separation effect is significantly improved; from Figure 5 It can be seen from C that Mn 0.43 Cd 0.57 S / 3%Cu2MoS4 has the highest carrier separation efficiency; in Figure 5 It can be seen from D that, compared with pure Mn 0.43 Cd 0.57 S, Mn 0.43 Cd 0.57 S / 3%Cu2MoS4 shows smaller overpotential, which means that it has stronger reduction capacity, also means that it is more conducive to photocatalytic hydrogen evolution reaction.

[0077] The above, only for the preferred specific embodiments of the present application, but the scope of protection of the present application is not limited to this, any skilled in the art of the technical personnel in the technical range disclosed by the present application, can easily think of changes or replacement, should be covered within the scope of protection of the present application. Therefore, the scope of protection of the present application should be subject to the scope of protection of the claims.

Claims

1. A method for synthesizing Mn 0.43 Cd 0.57 S / Cu2MoS4 photocatalyst by a solvothermal method, characterized in that, The method comprises the following steps: (1) dispersing cuprous oxide in ethylene glycol, then adding sodium molybdate and thioacetamide to perform a solvothermal reaction to obtain molybdenum sulfide copper; (2) Mn acetate, Cd acetate and NaOH are mixed to carry out displacement reaction, then thiocetamide and the MoCuS synthesized in step (1) are added to carry out hydrothermal reaction, to obtain the Mn 0.43 Cd 0.57 S / Cu2MoS4 photocatalyst; the mass of the added MoCuS is 1%~5% of the mass of the hydrothermally synthesized CdMnS.

2. The method for synthesizing Mn 0.43 Cd 0.57 A method for synthesizing S / Cu2MoS4 photocatalyst, characterized in that, In step (1), the molar ratio of cuprous oxide, sodium molybdate and thioacetamide is 0.16:0.19:

1.

3. The method for synthesizing Mn 0.43 Cd 0.57 A method for synthesizing S / Cu2MoS4 photocatalyst, characterized in that, In step (1), the temperature of the solvothermal reaction is 160℃, and the time is 12h.

4. The method for synthesizing Mn 0.43 Cd 0.57 A method for synthesizing S / Cu2MoS4 photocatalyst, characterized in that, In step (1), the preparation method of cuprous oxide comprises the following steps: mixing copper sulfate, sodium citrate and sodium hydroxide to perform a double decomposition reaction, then adding an ascorbic acid aqueous solution to perform an oxidation-reduction reaction to obtain the cuprous oxide.

5. The method for synthesizing Mn 0.43 Cd 0.57 S / Cu2MoS4 photocatalyst, characterized in that, The molar ratio of copper sulfate, sodium citrate and sodium hydroxide is 0.06:0.017:1; The molar ratio of copper sulfate to ascorbic acid in the ascorbic acid aqueous solution is 1:

1.

6. The method for synthesizing Mn 0.43 Cd 0.57 The method for synthesizing S / Cu2MoS4 photocatalyst, characterized in that, In step (2), the manganese acetate is tetrahydrate manganese acetate, and the cadmium acetate is dihydrate cadmium acetate.

7. The method for synthesizing Mn 0.43 Cd 0.57 A method for synthesizing S / Cu2MoS4 photocatalyst, characterized in that, In step (2), the molar ratio of tetrahydrate manganese acetate, dihydrate cadmium acetate and sodium hydroxide is 1:1:8; the molar ratio of tetrahydrate manganese acetate and thioacetamide is 1:

4.

8. The method for synthesizing Mn 0.43 Cd 0.57 A method for synthesizing S / Cu2MoS4 photocatalyst, characterized in that, In step (2), the temperature of the hydrothermal reaction is 180℃, and the time is 18h.

9. Mn prepared by the process of any one of claims 1 to 8 0.43 Cd 0.57 S / Cu2MoS4 photocatalyst.

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