A preparation process of zinc anode modified by molybdenum disulfide

Abstract

This invention belongs to the field of aqueous ion batteries, specifically a zinc anode preparation process based on molybdenum disulfide modification. Addressing the potential problems of hydrogen evolution, passivation, and dendrite formation in bare zinc anodes in existing aqueous battery systems, the following solution is proposed, comprising the following steps: S1: Preparation of the electrodeposition solution: Weigh sodium perchlorate and ammonium tetrathiomolybdate and dilute to volume in a volumetric flask for later use. This invention can controllably control the MoS2 content and morphology on the zinc sheet surface, alleviate corrosion on the anode electrode surface, effectively guide zinc ion deposition and shedding, and inhibit zinc dendrite formation, thereby improving its electrochemical performance. It possesses good specific capacity and cycle stability and can be used as the anode in aqueous zinc-ion batteries. The preparation method is simple, the equipment is inexpensive, the operation is safe and simple, and the preparation process does not require hazardous chemicals or strong oxidizing or highly toxic chemicals, offering advantages of environmental friendliness and safe control.

Description

Technical Field

[0001] This invention relates to the field of aqueous ion battery technology, and in particular to a process for preparing a zinc anode based on molybdenum disulfide modification. Background Technology

[0002] With the increasing consumption of petrochemical fuels and the growing severity of environmental problems, developing new energy sources such as wind, nuclear, solar, and tidal power can address these issues. However, due to the intermittent nature of these new energy sources, suitable energy storage methods are particularly important. Electrochemical energy storage offers advantages such as ease of use, lack of geographical limitations, high conversion efficiency, and high specific energy. Among these, aqueous secondary batteries can store and convert both chemical and electrical energy. Compared to non-aqueous batteries, aqueous secondary batteries do not have the problem of flammable or explosive electrolytes. Furthermore, aqueous secondary batteries also possess higher power and ionic conductivity.

[0003] The primary negative electrode material in zinc-ion batteries is metallic zinc. Zinc (Zn) is considered an ideal material for the negative electrode of aqueous batteries due to its abundant resources and good conductivity. However, during charge and discharge, zinc electrodes exhibit drawbacks such as dendrite formation, self-corrosion, and passivation, which can easily lead to a reduction in battery cycle life. During charge and discharge, zinc ions repeatedly dissolve and deposit on the surface of metallic zinc, forming dendritic deposits. These deposits grow with increasing cycle count, eventually forming zinc dendrites. These zinc dendrites not only easily cause short circuits but also lead to a decrease in the capacity of the zinc-ion battery. During discharge, insoluble products such as ZnO or Zn(OH)2 are generated on the surface of the zinc negative electrode, affecting the normal dissolution of zinc and causing the zinc electrode to lose activity and become "passive." Passivation of the zinc electrode leads to severe capacity decay and a decline in cycle performance. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies, such as hydrogen evolution, passivation, and dendrite formation, that may occur with bare zinc anodes in water battery systems. This invention proposes a zinc anode preparation process based on molybdenum disulfide modification.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A process for preparing a zinc anode based on molybdenum disulfide modification includes the following steps:

[0007] S1: Preparation of electrodeposition solution: Weigh sodium perchlorate and ammonium tetrathiomolybdate and dilute to volume in a volumetric flask for later use;

[0008] S2: Preparation of zinc sheet substrate: Cut the zinc sheet into zinc sheets of the same size, clean the surface of the zinc sheet with deionized water and ethanol in turn, vacuum dry, and mark the zinc sheet to ensure consistent deposition area;

[0009] S3: Preparation of MoS2 / Zn composite anode: Electrodeposition was performed using a three-electrode system with a calomel electrode as the reference electrode and a Pt sheet as the counter electrode. The solution prepared in step S1 was used as the deposition electrolyte. The zinc sheet obtained in step S2 was used as the working electrode for cyclic voltammetric electrodeposition. The modified layer of MoS2 nanospheres was coated onto the zinc sheet. The sheet was then removed, rinsed with deionized water, and dried under vacuum for later use.

[0010] Preferably, in S1, the concentration of sodium perchlorate is 0.1-1 mol / L.

[0011] Preferably, in step S2, the zinc sheet has a thickness of 0.03-1 mm, and the cut zinc sheet has a length of 1-5 cm and a width of 1-5 cm.

[0012] Preferably, in S3, the cyclic voltammetric deposition voltage range is -1 to 1V.

[0013] Preferably, in step S3, the number of cyclic voltammetric electrodeposition cycles is 5-30, and the deposition scan number is 0.01-0.0001 mVs-1.

[0014] Preferably, in S1, the concentration of ammonium tetrathiomolybdate is 1-10 mmol / L.

[0015] Preferably, in S2, the marked deposition area is 1-4 cm2.

[0016] Preferably, in step S2, the zinc sheet is cut into zinc sheets of the same size, the surface of the zinc sheet is cleaned with deionized water and ethanol in sequence, dried under vacuum for ten minutes, and marked on the zinc sheet to ensure that the deposition area is consistent.

[0017] Currently, much research focuses on protecting zinc electrodes by coating the surface of the zinc anode with a thin inert layer. This protective layer can effectively guide the deposition and shedding of zinc ions on the zinc anode surface, thereby improving the structural and performance stability of the Zn anode. Electrodeposition can be used to attach a uniform deposit film to the metal surface, and the film thickness can be precisely controlled at the nanometer level. Nanostructured molybdenum disulfide (MoS2) has excellent electrochemical properties and plays an important role in improving the performance of electrode materials, making it a potential choice for the protective layer of zinc anode materials. By forming a thin and uniform molybdenum disulfide film on the zinc surface through electrodeposition, the deposition and shedding of zinc ions on the zinc anode surface can be effectively guided, inhibiting the formation of zinc dendrites and thus improving its electrochemical performance.

[0018] The beneficial effects of the zinc anode preparation process based on molybdenum disulfide modification described in this invention are as follows:

[0019] 1. This invention uses cyclic voltammetry for electrodeposition to form molybdenum disulfide nanospheres on the surface of a zinc sheet. These nanospheres are attached to the zinc foil surface in a stacked manner to form a MoS2 modification layer without the need for any binder. Furthermore, this method allows for controllable control of the MoS2 content and morphology on the zinc sheet surface.

[0020] 2. This invention forms MoS2 nanospheres on the zinc surface and stacks them into a thin and uniform molybdenum disulfide film. The nanoparticles formed on the surface facilitate the penetration of the electrolyte into the interior, reducing the direct contact between water in the electrolyte and the zinc negative electrode, thereby alleviating the corrosion phenomenon on the surface of the negative electrode sheet. At the same time, it can control the deposition sites of zinc ions on the electrode surface, providing more active sites for zinc deposition / removal, effectively guiding zinc ion deposition and removal, inhibiting the formation of zinc dendrites, and thus improving its electrochemical performance.

[0021] 3. This invention has good specific capacity and cycle stability, and can be used as the negative electrode of aqueous zinc-ion batteries.

[0022] 4. The preparation method of this invention is simple, the equipment is inexpensive, the operation steps are safe and simple, and the preparation process does not require hazardous chemicals or strong oxidizing or highly toxic chemicals, which has the advantages of being environmentally friendly and safe and controllable. Attached Figure Description

[0023] Figure 1 This is a diagram illustrating the deposition process of a MoS2 / Zn composite electrode based on a molybdenum disulfide-modified zinc anode fabrication process proposed in this invention.

[0024] Figure 2 This is a SEM image of the surface of a MoS2 / Zn composite anode prepared using a molybdenum disulfide-modified zinc anode process proposed in this invention.

[0025] Figure 3 The graph shows the cycling stability curve of a MoS2 / Zn composite anode prepared by a molybdenum disulfide-modified zinc anode process proposed in this invention in a symmetrical cell.

[0026] Figure 4 The image shows the electrochemical performance of a MoS2 / Zn composite anode prepared using a molybdenum disulfide-modified zinc anode process proposed in this invention. Detailed Implementation

[0027] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0028] Example 1

[0029] Reference Figures 1-4A process for preparing a zinc anode based on molybdenum disulfide modification includes the following steps:

[0030] S1: Preparation of electrodeposition solution: Weigh sodium perchlorate and ammonium tetrathiomolybdate and dilute to volume in a volumetric flask for later use;

[0031] S2: Preparation of zinc sheet substrate: Cut the zinc sheet into zinc sheets of the same size, clean the surface of the zinc sheet with deionized water and ethanol in turn, vacuum dry, and mark the zinc sheet to ensure consistent deposition area;

[0032] S3: Preparation of MoS2 / Zn composite anode: Electrodeposition was performed using a three-electrode system with a calomel electrode as the reference electrode and a Pt sheet as the counter electrode. The solution prepared in step S1 was used as the deposition electrolyte. The zinc sheet obtained in step S2 was used as the working electrode for cyclic voltammetric electrodeposition. The modified layer of MoS2 nanospheres was coated onto the zinc sheet. The sheet was then removed, rinsed with deionized water, and dried under vacuum for later use.

[0033] In this embodiment, the concentration of sodium perchlorate in S1 is 0.1 mol / L.

[0034] In this embodiment, in S2, the zinc sheet has a thickness of 0.03 mm, and the cut zinc sheet is 1 cm long and 1 cm wide.

[0035] In this embodiment, the cyclic voltammetric deposition voltage used in S3 is in the range of -1V.

[0036] In this embodiment, in S3, the number of cyclic voltammetric electrodeposition cycles is 5, and the deposition sweep number is 0.01 mVs-1.

[0037] In this embodiment, the concentration of ammonium tetrathiomolybdate in S1 is 1 mmol / L.

[0038] In this embodiment, in S2, the marked deposition area is 1 cm2.

[0039] In this embodiment, in step S2, the zinc sheet is cut into zinc sheets of the same size, the surface of the zinc sheet is cleaned with deionized water and ethanol in sequence, dried under vacuum for ten minutes, and marked on the zinc sheet to ensure that the deposition area is consistent.

[0040] Figure 1 For the deposition process of molybdenum disulfide-modified zinc anode, from Figure 1 The image shows a zinc composite negative electrode modified with molybdenum disulfide deposited on a bare zinc substrate. It undergoes a significant color change, transforming from a silvery-white substrate to a brownish-red film, indicating that nano-MoS2 spheres have been deposited on the bare zinc substrate.

[0041] Figure 2This is a scanning electron microscope (SEM) image of a zinc anode modified with molybdenum disulfide. The molybdenum disulfide nanospheres have a particle size ranging from 10 to 50 nm and are attached to the zinc foil surface in a stacked manner.

[0042] Figure 3 The electrochemical performance of the molybdenum disulfide-modified electrode in a symmetric cell is shown. Compared with the bare zinc symmetric cell, the molybdenum disulfide-modified zinc anode has a smaller deposition / stripping voltage window and higher stability, indicating that the MoS2 modification layer can effectively guide the deposition and stripping of zinc ions on the zinc anode surface and suppress the formation of zinc dendrites.

[0043] Figure 4 To assess the electrochemical performance of the molybdenum disulfide-modified zinc anode, a zinc composite material modified with molybdenum disulfide was used as the anode and MnO2 as the cathode in a coin cell. The results showed that the molybdenum disulfide-modified anode exhibited superior electrochemical performance.

[0044] The purpose of this invention is to prepare a molybdenum disulfide-modified zinc composite material with excellent electrochemical performance by electrodepositing a molybdenum disulfide modified layer on the surface of a zinc sheet using cyclic voltammetry. This invention proposes a method for preparing a molybdenum disulfide-modified zinc anode (MoS2 / Zn) and its application. The MoS2 / Zn composite anode of this invention consists of a bare zinc sheet substrate and a modified layer of stacked MoS2 nanospheres, solving problems such as hydrogen evolution, passivation, and dendrite formation, while ensuring the zinc storage performance of the electrode. Ultimately, this improves the performance of the zinc anode and provides theoretical and experimental guidance for the research of similar materials. The MoS2 / Zn composite anode preparation method of this invention is simple, low-cost, and does not require the use of highly toxic or strong oxidizing chemicals, making it environmentally friendly.

[0045] Example 2

[0046] A process for preparing a zinc anode based on molybdenum disulfide modification includes the following steps:

[0047] S1: Preparation of electrodeposition solution: Weigh sodium perchlorate and ammonium tetrathiomolybdate and dilute to volume in a volumetric flask for later use;

[0048] S2: Preparation of zinc sheet substrate: Cut the zinc sheet into zinc sheets of the same size, clean the surface of the zinc sheet with deionized water and ethanol in turn, vacuum dry, and mark the zinc sheet to ensure consistent deposition area;

[0049] S3: Preparation of MoS2 / Zn composite anode: Electrodeposition was performed using a three-electrode system with a calomel electrode as the reference electrode and a Pt sheet as the counter electrode. The solution prepared in step S1 was used as the deposition electrolyte. The zinc sheet obtained in step S2 was used as the working electrode for cyclic voltammetric electrodeposition. The modified layer of MoS2 nanospheres was coated onto the zinc sheet. The sheet was then removed, rinsed with deionized water, and dried under vacuum for later use.

[0050] In this embodiment, the concentration of sodium perchlorate in S1 is 0.5 mol / L.

[0051] In this embodiment, in S2, the zinc sheet has a thickness of 0.5 mm, and the cut zinc sheet is 3 cm long and 3 cm wide.

[0052] In this embodiment, the cyclic voltammetric deposition voltage range used in S3 is 0.5V.

[0053] In this embodiment, in S3, the number of cyclic voltammetric electrodeposition cycles is 15, and the deposition sweep number is 0.0001 mVs-1.

[0054] In this embodiment, the concentration of ammonium tetrathiomolybdate in S1 is 5 mmol / L.

[0055] In this embodiment, in S2, the marked deposition area is 2 cm2.

[0056] In this embodiment, in step S2, the zinc sheet is cut into zinc sheets of the same size, the surface of the zinc sheet is cleaned with deionized water and ethanol in sequence, dried under vacuum for ten minutes, and marked on the zinc sheet to ensure that the deposition area is consistent.

[0057] The purpose of this invention is to prepare a molybdenum disulfide-modified zinc composite material with excellent electrochemical performance by electrodepositing a molybdenum disulfide modified layer on the surface of a zinc sheet using cyclic voltammetry. This invention proposes a method for preparing a molybdenum disulfide-modified zinc anode (MoS2 / Zn) and its application. The MoS2 / Zn composite anode of this invention consists of a bare zinc sheet substrate and a modified layer of stacked MoS2 nanospheres, solving problems such as hydrogen evolution, passivation, and dendrite formation, while ensuring the zinc storage performance of the electrode. Ultimately, this improves the performance of the zinc anode and provides theoretical and experimental guidance for the research of similar materials. The MoS2 / Zn composite anode preparation method of this invention is simple, low-cost, and does not require the use of highly toxic or strong oxidizing chemicals, making it environmentally friendly.

[0058] Example 3

[0059] A process for preparing a zinc anode based on molybdenum disulfide modification includes the following steps:

[0060] S1: Preparation of electrodeposition solution: Weigh sodium perchlorate and ammonium tetrathiomolybdate and dilute to volume in a volumetric flask for later use;

[0061] S2: Preparation of zinc sheet substrate: Cut the zinc sheet into zinc sheets of the same size, clean the surface of the zinc sheet with deionized water and ethanol in turn, vacuum dry, and mark the zinc sheet to ensure consistent deposition area;

[0062] S3: Preparation of MoS2 / Zn composite anode: Electrodeposition was performed using a three-electrode system with a calomel electrode as the reference electrode and a Pt sheet as the counter electrode. The solution prepared in step S1 was used as the deposition electrolyte. The zinc sheet obtained in step S2 was used as the working electrode for cyclic voltammetric electrodeposition. The modified layer of MoS2 nanospheres was coated onto the zinc sheet. The sheet was then removed, rinsed with deionized water, and dried under vacuum for later use.

[0063] In this embodiment, the concentration of sodium perchlorate in S1 is 1 mol / L.

[0064] In this embodiment, in S2, the zinc sheet is 1 mm thick, and the cut zinc sheet is 5 cm long and 5 cm wide.

[0065] In this embodiment, the cyclic voltammetric deposition voltage range used in S3 is 1V.

[0066] In this embodiment, in S3, the number of cyclic voltammetric electrodeposition cycles is 30, and the deposition sweep number is 0.0001 mVs-1.

[0067] In this embodiment, the concentration of ammonium tetrathiomolybdate in S1 is 10 mmol / L.

[0068] In this embodiment, in S2, the marked deposition area is 4 cm2.

[0069] In this embodiment, in step S2, the zinc sheet is cut into zinc sheets of the same size, the surface of the zinc sheet is cleaned with deionized water and ethanol in sequence, dried under vacuum for ten minutes, and marked on the zinc sheet to ensure that the deposition area is consistent.

[0070] The purpose of this invention is to prepare a molybdenum disulfide-modified zinc composite material with excellent electrochemical performance by electrodepositing a molybdenum disulfide modified layer on the surface of a zinc sheet using cyclic voltammetry. This invention proposes a method for preparing a molybdenum disulfide-modified zinc anode (MoS2 / Zn) and its application. The MoS2 / Zn composite anode of this invention consists of a bare zinc sheet substrate and a modified layer of stacked MoS2 nanospheres, solving problems such as hydrogen evolution, passivation, and dendrite formation, while ensuring the zinc storage performance of the electrode. Ultimately, this improves the performance of the zinc anode and provides theoretical and experimental guidance for the research of similar materials. The MoS2 / Zn composite anode preparation method of this invention is simple, low-cost, and does not require the use of highly toxic or strong oxidizing chemicals, making it environmentally friendly.

[0071] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A process for preparing a zinc anode based on molybdenum disulfide modification, characterized in that, Includes the following steps: S1: Preparation of electrodeposition solution: Weigh sodium perchlorate and ammonium tetrathiomolybdate and dilute to volume in a volumetric flask for later use; S2: Preparation of zinc sheet substrate: Cut the zinc sheet into zinc sheets of the same size, clean the surface of the zinc sheet with deionized water and ethanol in turn, vacuum dry, and mark the zinc sheet to ensure consistent deposition area; S3: Preparation of MoS2 / Zn composite negative electrode: Electrodeposition is performed using a three-electrode system with a calomel electrode as the reference electrode and a Pt sheet as the counter electrode. The solution prepared in step S1 is used as the deposition electrolyte. The zinc sheet obtained in step S2 is used as the working electrode for cyclic voltammetric electrodeposition. The number of cyclic voltammetric electrodeposition cycles is 5-30, the deposition sweep number is 0.01-0.0001 mVs-1, and the cyclic voltammetric deposition voltage range is -1-1V. This results in the formation of molybdenum disulfide nanospheres on the surface of the zinc sheet, which are attached to the zinc foil surface in a stacked manner, forming a MoS2 nanosphere modification layer coated on the zinc sheet. The sheet is then removed, rinsed with deionized water, and dried under vacuum for later use.

2. The zinc anode preparation process based on molybdenum disulfide modification according to claim 1, characterized in that, In S1, the concentration of sodium perchlorate is 0.1-1 mol / L.

3. The zinc anode preparation process based on molybdenum disulfide modification according to claim 1, characterized in that, In S2, the zinc sheet has a thickness of 0.03-1mm, and the cut zinc sheet has a length of 1-5cm and a width of 1-5cm.

4. The zinc anode preparation process based on molybdenum disulfide modification according to claim 1, characterized in that, In S1, the concentration of ammonium tetrathiomolybdate is 1-10 mmol / L.

5. The zinc anode preparation process based on molybdenum disulfide modification according to claim 4, characterized in that, In S2, the marked deposition area is 1-4 cm². 2 .

6. The zinc anode preparation process based on molybdenum disulfide modification according to claim 1, characterized in that, In step S2, zinc sheets are cut into zinc sheets of the same size, the surface of the zinc sheets is cleaned with deionized water and ethanol in sequence, dried under vacuum for ten minutes, and marked on the zinc sheets to ensure consistent deposition area.

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