Monovalent aluminum ions dissolved in electrolyte and design method and device thereof
By constructing a graphene thin-plate electrode model and adjusting the applied electrode potential, +1 valence aluminum ions dissolved in the electrolyte were successfully prepared, solving the problem of slow aluminum ion dissolution and deposition processes, realizing aluminum ion preparation under conventional conditions, and enriching the existence forms and application potential of metal ions in the electrolyte.
Patent Information
- Application Number
- CN202410492684.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-23
- Publication Date
- 2025-10-24
AI Technical Summary
Under existing technologies, the dissolution and deposition process of aluminum ions is slow, making it difficult to prepare +1-valent aluminum ions in the electrolyte. The experimental conditions are harsh and difficult to control.
By constructing a graphene thin-plate electrode model with N layers of graphene film, adding a sodium halide electrolyte environment, minimizing energy, constructing an adsorption structure using first-principles molecular dynamics, and adjusting the applied electrode potential, aluminum atoms are stably adsorbed and converted to +1 valence, thus preparing aluminum ions dissolved in the electrolyte.
The successful preparation of +1 valent aluminum ions under normal conditions enriches the forms in which metal ions exist in electrolytes, opens up new avenues for the battery field, provides in-depth research on the electron transfer mechanism during metal dissolution, and guides research on the preparation of other ions.
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Figure CN120833873A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of computational materials chemistry, in particular to a monovalent aluminum ion dissolved in an electrolyte and a design method and device thereof. BACKGROUND
[0002] Aluminum is the third most abundant element in the earth's crust, after oxygen and silicon, and is the most abundant metal element in the earth's crust. Because of its abundance, it has become the second largest metal after steel. Because of its outermost 3-electron configuration, it is easy to oxidize to form trivalent aluminum compounds. Alumina, an aluminum compound, has excellent mechanical properties, with a strength second only to that of diamond. The mechanical properties of aluminum have been fully exploited. However, due to its unique outermost 3s 2 3p 1 , its chemical properties may become a hot research direction in the future.
[0003] The electrochemical dissolution and deposition of specific ions is a complex chemical reaction process. Because the dissolution of ions involves multiple complex interactions with carriers, the control of specific ions is highly dependent on empirical design. Ion dissolution involves electrolyte environment, applied potential, surface charge density, electric field, and ion characteristics. The commonly used methods include atomic doping, atomic adsorption, creating vacancy defects, changing electrolyte environment, and changing applied potential. Among them, atomic adsorption can directly modify the electrode surface to control the surface charge density and thus control the dissolution and deposition of ions, which has great development prospects. Therefore, the means to control the dissolution of aluminum ions include changing the electrolyte environment, atomic doping, creating defects, and atomic adsorption. Adjusting the surface charge density of the aluminum electrode will be the key to controlling the ion dissolution and deposition process. However, the atomic adsorption experiment has strict requirements on experimental conditions and experimental personnel, which has slowed down the development of the control of ion dissolution and deposition process. The existing technology cannot obtain +1 valence aluminum ions under conventional conditions. Therefore, it is of great significance to find a way to adjust the surface charge distribution to control the dissolution and deposition process of specific ions. SUMMARY
[0004] The present application aims to solve the problems of slow dissolution and deposition process of specific ions, difficulty in experiment, and inability to prepare +1 valence aluminum ions under conventional conditions, and provides a monovalent aluminum ion dissolved in an electrolyte and a design method and device thereof.
[0005] To achieve the above-mentioned purpose, the present application provides the following technical solutions:
[0006] In a first aspect, the present application provides a monovalent aluminum ion dissolved in an electrolyte.
[0007] The electrolyte comprises a strong electrolyte, preferably a sodium halide electrolyte.
[0008] In a second aspect, the present application provides a design method of monovalent aluminum ion dissolved in electrolyte, comprising the following steps:
[0009] S1, constructing a graphene sheet electrode model with N layers of graphene film, adding a sodium halide electrolyte environment to the electrode model and performing energy minimization to obtain the energy most stable structure of the graphene sheet electrode;
[0010] S2, using first-principles molecular dynamics to construct the adsorption structure of solute Al atoms and graphene sheet electrode, and performing energy minimization to enable Al atoms to be stably adsorbed on the electrode surface;
[0011] S3, fixing the coordinates of graphene C atoms, applying an external electrode potential to the electrode model, adjusting the electrode potential so that the total energy of the graphene atom-Al atom system continues to decrease during the process of Al atoms moving away from the electrode surface, and the charge of Al atoms changes into stable +1 valence, thereby obtaining monovalent aluminum ion dissolved in electrolyte.
[0012] In the S1 step, the specific design method of the energy most stable structure of the graphene sheet electrode comprises the following steps:
[0013] S11, stacking N layers of single-layer graphene film to obtain a graphene sheet electrode model, and performing energy minimization in the three coordinate axes directions of the Cartesian three-dimensional coordinate system to obtain a first relaxed graphene sheet electrode model; wherein N is a natural number ≥ 3;
[0014] S12, adding a sodium halide electrolyte environment to the first relaxed graphene sheet electrode model, and continuing to perform energy minimization to obtain a second relaxed graphene sheet electrode model; wherein the sodium halide is at least one of NaF, NaCl, NaI and NaBr, the concentration of the sodium halide is 0.3-2M, preferably 0.5-1M, and the sodium halide is preferably 1M NaCl;
[0015] S13, geometrically optimizing the second relaxed graphene sheet electrode model to obtain the energy most stable structure of the graphene sheet electrode.
[0016] As a preferred, in step S11, a vacuum layer is provided between the atomic layers of the graphene film. As a preferred, the thickness of the vacuum layer is
[0017] As a preferred, in step S12, the key parameters for energy minimization are set as follows: K points are 10×10×1, and the cutoff energy is 598eV, wherein the energy difference between two consecutive iteration steps of electron cloud density, atomic or ionic coordinates and lattice constant is 2.72×10-7 eV, 2.72*10 -7 eV and 2.72*10 -8 eV.
[0018] As preferred, in step S13, the geometry optimization is performed by using self-consistent calculation to relax the system, and the key parameters are set as follows: the K-point is 10*10*1, the cutoff energy is 598 eV, and the energy difference of two successive iteration steps of electron cloud density, atomic or ion coordinates and lattice constant is 2.72*10 -7 eV, 2.72*10 -7 eV and 2.72*10 -8 eV.
[0019] In step S2, in the adsorption structure, the Al atom is adsorbed on the Top position of the C atom (i.e. the surface layer of the graphene C atom).
[0020] In the above design method, relevant data are recorded, for example: when the Al atom can be stably adsorbed on the electrode surface, the adsorption structure information is recorded, the adsorption structure information includes the graphene C atom coordinates, atomic charge state and the total energy of the graphene atom-Al atom system; when the graphene thin plate electrode obtains the most stable structure, the graphene C atom coordinates, atomic charge state and the total energy of the graphene atom system in the most stable structure are recorded.
[0021] In a specific embodiment, the electrolyte is a 1M NaF aqueous solution, and since NaF is a strong electrolyte, similar strong electrolyte aqueous solutions (such as a 0.5M NaCl aqueous solution) also belong to the protection scope of the present patent.
[0022] The present application also discloses a design device for monovalent aluminum ions dissolved in an electrolyte, comprising a memory and one or more processors, the memory stores executable codes, and the one or more processors execute the executable codes to implement the above-mentioned design method for monovalent aluminum ions dissolved in an electrolyte.
[0023] The present application also discloses a computer readable storage medium, which stores a program, and the program is executed by a processor to implement the above-mentioned design method for monovalent aluminum ions dissolved in an electrolyte.
[0024] The present application has the following beneficial effects:
[0025] 1. The present application successfully prepares +1 valence aluminum ions under conventional conditions for the first time, breaking the previous limitation that aluminum ions can only exist in the form of +3 valence in electrolyte. This innovative breakthrough not only enriches the existence form of metal ions in electrolyte, but also opens up a new way for the application of metal ions in the field of batteries.
[0026] 2, The method of the present application has important reference significance for in-depth exploration of the electron transfer mechanism in the metal dissolution process. Through in-depth study of the preparation process of +1 valence aluminum ions, the electronic behavior of metal ions in the dissolution process can be further understood, providing a new direction for the preparation research of other special ions, and having certain guiding significance for the future use of first-principle calculation to guide the design of experiments. BRIEF DESCRIPTION OF DRAWINGS
[0027] Figure 1 is a schematic diagram of a calculation model of the graphene electrode adsorbing solute Al atoms in Example 1;
[0028] Figure 2 is a system energy curve and solute Al atom charge state curve under different applied electrode potentials in Example 1;
[0029] Figure 3 is a structural schematic diagram of a design device for dissolving monovalent aluminum ions in an electrolyte according to the present application;
[0030] Figure 4 is a system energy curve under different applied electrode potentials in the comparative example;
[0031] Figure 5 is a solute Al atom charge state curve under different applied electrode potentials in the comparative example. DETAILED DESCRIPTION
[0032] In order to make the purpose, technical scheme and advantages of the present application more clear and obvious, the present application is further described in detail below through the drawings and examples. However, it should be understood that the specific examples described herein are only used to explain the present application and do not limit the scope of the present application. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present application.
[0033] Example 1:
[0034] The present application provides a design method for dissolving monovalent aluminum ions in an electrolyte, which specifically includes the following operations:
[0035] (1) Manually construct a 3-layer atomic thickness graphene sheet electrode in a three-dimensional coordinate system. Using the density functional theory (DFT) method, combined with the first-principles calculation software JDFTx, an energy minimization is performed in the xyz three coordinate axis directions using a supercell model and periodic boundary conditions (PBC) to obtain a first-relaxed graphene sheet electrode model. The first-relaxed graphene sheet electrode is filled with electrolyte on both sides, and an energy minimization is continued to obtain a second-relaxed graphene sheet electrode model. The electrolyte uses a SaLSA (spherically averaged liquid sensitive assumption) continuous model, with a concentration of 1M Na + and F - . The exchange correlation function uses generalized gradient approximation (GGA) with PBEsol function setting. The pseudopotential uses GBRV ultra-soft pseudopotential. The K point is set to 10x10x1, and the energy cutoff threshold is 598 electron volts. The key parameters for energy minimization are set as follows: the two consecutive iteration step energy differences of electron cloud density, atomic or ionic coordinates, and lattice constant are 2.72x10 -7 eV, 2.72x10 -7 eV, and 2.72x10 -8 eV, respectively.
[0036] (2) Geometric optimization of the second-relaxed graphene sheet electrode model is performed using the JDFTx software to obtain the energy most stable structure of the graphene sheet electrode. The second-relaxed graphene sheet electrode is 3 layers, the system structure is a 4x8x3 supercell, and the minimum unit contains a total of 96 atoms, with 32 atoms per layer. Geometric optimization is performed using self-consistent calculation for system relaxation, and the K point, cutoff energy, electron cloud density, atomic or ionic coordinates, and two consecutive iteration step energy difference of lattice constant are the same as in step (1).
[0037] (3) Obtain the energy most stable structure in step (2), add solute Al atoms to the Top position of the graphene electrode carbon atoms (i.e., the most surface layer of graphene C atoms), while fixing all C atoms on the electrode, and only perform geometric optimization of the solute Al atoms by quasi-Newton method to obtain the specific sites where the solute Al atoms can be stably adsorbed on the electrode surface, as shown in Figure 1 .
[0038] (4) On the basis of step (3), move the solute Al atoms away from the electrode surface, and continuously increase the applied electrode potential to promote the dissolution process of the solute Al atoms. Through calculation, the system energy (i.e., the total energy of the graphene atom-Al atom system) change curve and the solute Al atom charge state change curve with the distance from the electrode surface can be obtained under different applied electrode potentials. The calculated results are as follows:Figure 2
[0039] Figure 2 Figure 1 shows the energy of the whole system and the net charge of the solute atom Al as a function of the distance of the solute atom Al from the stable adsorption site on the surface of the electrode. The left graph shows the energy of the whole system as a function of the distance of the solute atom Al from the stable adsorption site on the surface of the electrode. The horizontal axis represents the distance of the solute atom Al from the stable adsorption site on the surface of the electrode, and the vertical axis represents the energy of the whole system. The right graph shows the net charge of the solute atom Al as a function of the distance of the solute atom Al from the stable adsorption site on the surface of the electrode. The horizontal axis represents the distance of the solute atom Al from the stable adsorption site on the surface of the electrode, and the vertical axis represents the net charge of the solute atom Al. As can be seen from Figure 1, the energy of the whole system and the net charge of the solute atom Al as a function of the distance of the solute atom Al from the stable adsorption site on the surface of the electrode are almost the same as those shown in Figure 1 of the reference example 1. Figure 2 As can be seen from Figure 2, by adjusting the applied electrode potential, the total energy of the graphene atom-Al atom whole system can be continuously reduced during the process of the Al atom moving away from the surface of the electrode, and the charge of the Al atom is changed to a stable +1 valence, thereby obtaining a monovalent aluminum ion dissolved in the electrolyte.
[0040] Example 2:
[0041] Referring to the reference example 1, the number of atomic layers of the graphene film in the graphene sheet electrode structure is increased, and a graphene sheet electrode model composed of more than three layers of graphene film is used to construct the adsorption structure of the solute Al atom and the graphene sheet electrode. The surface structure of more than three layers of graphene is almost the same as that of the graphene surface structure of the example 1. It is found that by adjusting the applied electrode potential, monovalent aluminum ions dissolved in the electrolyte can also be obtained.
[0042] Comparative Example:
[0043] Referring to the reference example 1, the adsorption structure of the solute Al atom and the Al(100) electrode is constructed, and the difference between the present comparative example and the example 1 is that the electrode material of the present comparative example is different from that of the example 1. The distance of the solute Al atom from the surface of the electrode is moved, and the dissolution process of the solute Al atom is promoted by continuously increasing the applied electrode potential. The change curve of the system energy (i.e., the total energy of the electrode Al atom-solute Al atom whole system) and the charge state change curve of the solute Al atom as a function of the distance of the solute Al atom from the surface of the electrode under different applied electrode potentials can be obtained by calculation. The calculated results are shown in Figure 3 and Figure 4. Figure 4 and 5
[0044] Figure 4 and Figure 5 In the figure, different color curves represent different applied electrode potentials in the system, and the dashed line represents that, at the electrode potential, there is an energy barrier on the dissolution path when the solute atom is far away from the electrode plate surface, so the solute atom cannot spontaneously dissolve at the applied electrode potential, and the solid line segment represents that spontaneous dissolution can be carried out at the corresponding applied electrode potential. Figure 4 The figure represents the change of the entire system energy at different applied electrode potentials, the horizontal coordinate represents the distance of the solute atom from the electrode surface, and the vertical coordinate represents the energy in the entire system. Figure 5 The figure represents the net charge of the solute atom at different applied electrode potentials, the horizontal coordinate represents the distance of the solute atom from the electrode surface, and the vertical coordinate represents the net charge of the solute atom. Figure 5 It can be seen that, with the Al electrode, the monovalent aluminum ion cannot spontaneously dissolve, and the monovalent aluminum ion dissolved in the electrolyte cannot be obtained.
[0045] The application uses first-principle calculation based on density functional theory to perform high-throughput calculation on the Al atom dissolution process of the three-layer graphene sheet electrode surface, and first invents a method for preparing +1 valence aluminum ions in an Al-graphene system by controlling the applied electrode potential. The preparation of specific ions is an important topic in the research and industrial fields, and this invention provides a way for the preparation of +1 valence aluminum ions and a new direction for the preparation and research of other special ions. It also has certain guiding significance for the future use of first-principle calculation to guide the design of experiments.
[0046] The device embodiment for dissolving monovalent aluminum ions in an electrolyte can be applied to any device with data processing capability, which can be a device or apparatus such as a computer. The device embodiment can be realized by software, or by hardware or a combination of software and hardware. Taking software realization as an example, as a logical device, it is formed by reading the corresponding computer program instructions in the non-volatile memory into the memory and running by the processor of the device with data processing capability. From the hardware level, as shown in Figure 3 The figure shows a hardware structure diagram of the device for dissolving monovalent aluminum ions in an electrolyte in any device with data processing capability. In addition to the processor, memory, network interface, and non-volatile memory shown in Figure 3 The device in the embodiment is usually provided with other hardware according to the actual functions of the device with data processing capability, and the functions and effects of the units in the device are realized in the implementation process of the corresponding steps in the above method, which will not be repeated here.
[0047] For the apparatus embodiment, since it basically corresponds to the method embodiment, the relevant part can be seen from the part of the method embodiment. The apparatus embodiment described above is only illustrative, wherein the units described as separate components can or can not be physically separated, and the components displayed as units can or can not be physical units, i.e., can be located in one place, or can be distributed to multiple network units. Part or all of the modules can be selected to achieve the purpose of the present application according to actual needs. Those skilled in the art can understand and implement it without creative labor.
[0048] The embodiment of the present application further provides a computer readable storage medium, which stores a program, and the program is executed by a processor to realize the design method of the monovalent aluminum ion dissolved in the electrolyte.
[0049] The computer readable storage medium can be an internal storage unit of any data processing device, such as a hard disk or a memory. The computer readable storage medium can also be an external storage device of any data processing device, such as a plug-in hard disk, a smart media card (SMC), an SD card, a flash card, etc. Further, the computer readable storage medium can include both the internal storage unit and the external storage device of any data processing device. The computer readable storage medium is used to store the computer program and other programs and data required by the data processing device, and can also be used to temporarily store data that has been output or will be output.
Claims
1. A monovalent aluminum ion dissolved in an electrolyte, characterized in that, The electrolyte comprises a strong electrolyte.
2. The monovalent aluminum ion of claim 1, wherein, The electrolyte is a sodium halide electrolyte.
3. A design method of monovalent aluminum ion dissolved in electrolyte, comprising the following steps: S1, constructing a graphene sheet electrode model with N layers of graphene film, adding a sodium halide electrolyte environment to the electrode model and performing energy minimization to obtain the energy most stable structure of the graphene sheet electrode; S2, constructing an adsorption structure of solute Al atom and graphene sheet electrode by first principle, performing energy minimization to make Al atom stably adsorbed on the electrode surface; S3, fixing the coordinates of graphene C atoms, applying an external electrode potential to the electrode model, adjusting the electrode potential so that the total energy of the graphene atom-Al atom whole system continuously decreases in the process of Al atom moving away from the electrode surface, and the Al atom charge changes into stable +1 valence, thereby obtaining monovalent aluminum ion dissolved in electrolyte.
4. The method of designing according to claim 3, wherein, In the S1 step, the specific design method of the energy most stable structure of the graphene sheet electrode comprises the following steps: S11, stacking N layers of single-layer graphene film to obtain a graphene sheet electrode model, performing energy minimization in the three coordinate axes directions of the Cartesian three-dimensional coordinate system to obtain a first relaxed graphene sheet electrode model; wherein N is a natural number greater than or equal to 3; S12, adding a sodium halide electrolyte environment to the first relaxed graphene sheet electrode model and continuing to perform energy minimization to obtain a second relaxed graphene sheet electrode model; S13, performing geometric optimization on the second relaxed graphene sheet electrode model to obtain the energy most stable structure of the graphene sheet electrode.
5. The method of designing according to claim 4, wherein, In step S11, vacuum layers are provided between the graphene film atomic layers.
6. The method of designing according to claim 5, wherein, The thickness of the vacuum layer is 7. The method of designing according to claim 4, wherein, In step S12, the key parameters for energy minimization are set as: K points are 10x10x1, cutoff energy is 598 eV, and the energy difference of two successive iteration steps for electron density, atomic or ionic coordinates, and lattice constants are 2.72x10 -7 eV, 2.72x10 -7 eV, and 2.72x10 -8 eV, respectively. In step S13, the geometry optimization is performed by using self-consistent calculation for system relaxation, and the key parameters are set as: K points are 10x10x1, cutoff energy is 598 eV, and the energy difference of two successive iteration steps for electron density, atomic or ionic coordinates, and lattice constants are 2.72x10 -7 eV, 2.72x10 -7 eV, and 2.72x10 -8 eV, respectively.
8. A method of designing according to any of claims 3-7, characterized in that, In step S2, in the adsorption structure, the Al atom is adsorbed on the Top position of the C atom.
9. A design device of monovalent aluminum ion dissolved in electrolyte, comprising a memory and one or more processors, the memory storing executable code, and the one or more processors executing the executable code to implement the design method of any one of claims 3-8.
10. A computer readable storage medium having a program stored thereon, the program being executed by a processor to implement the design method of any one of claims 3-8.