Organic ionic plastic crystal facilitating the conduction of anions and cations and a preparation method thereof

Abstract

This invention relates to the field of new materials, specifically to an organic ionic plastic crystal that facilitates the conduction of anions and cations and its preparation method. The method involves adding different concentrations of anion and cation additives to a tetrafluoroborate-based quaternary ammonium salt plastic crystal, dissolving them in an appropriate amount of acetonitrile, stirring thoroughly, removing the solvent by rotary evaporation, and then vacuum drying to obtain a mixture doped with different concentrations of anions and cations. The tetrafluoroborate-based quaternary ammonium salt plastic crystal obtained by the above method exhibits an ionic conductivity close to practical values ​​after the introduction of anions and cations. The internal conduction of anions and cations can improve the conductivity of the organic ionic plastic crystal, providing a possibility for developing solid electrolytes with high conductivity.

Description

Technical Field

[0001] This invention relates to the field of new materials, specifically to an organic ionic plastic crystal that facilitates the conduction of cations and anions and its preparation method. Background Technology

[0002] With increasing global energy demand, the need for high-performance and sustainable energy storage is constantly growing, driving the development of more and more electrochemical energy technologies. Lithium-ion batteries (LIBs), due to their high energy density, high operating voltage, and excellent cycle stability, are still considered a promising energy storage system for future applications and have been widely used. However, because they use liquid electrolytes, more and more safety issues have emerged during use, urgently requiring the search for a new type of lithium-ion battery with high stability, low flammability, and high ionic conductivity.

[0003] Organic ionic plastic crystals (OIPCs), as an emerging type of solid electrolyte, possess significant advantages over traditional materials, including stability, plasticity, non-flammability, and high ionic conductivity, making them highly promising for applications in lithium-ion batteries, dye-sensitized solar cells, and ferroelectric materials. During the continuous movement and rearrangement within their structure, OIPCs form defects that facilitate ion transport; however, their inherent conductivity is low. Doping with different ions can enhance internal defects, promote ion migration, and thus improve ionic conductivity. Some OIPCs are doped with a certain concentration of Li. + Subsequently, the ionic conductivity was significantly improved, and this type of plastic crystal can also react with Na+. + H + In addition to conduction, existing technologies have also explored the potential applications of anion conduction in OIPCs in certain specific batteries, achieving significant progress in this field. However, in existing reports, organic ionic plastic crystals can only conduct cations or only anions, and cannot conduct the other type of ion.

[0004] Therefore, combining the excellent properties of organic ionic plastic crystals, finding a solution to better improve ionic conductivity has become one of the technical problems that urgently need to be solved by those skilled in the art. Summary of the Invention

[0005] This invention provides an organic ionic plastic crystal that facilitates the conduction of anions and cations, and a method for preparing the same. By adding different concentrations of anion and cation additives to a tetrafluoroborate-based quaternary ammonium salt plastic crystal, simultaneously adding an appropriate amount of acetonitrile to dissolve the additives, stirring thoroughly, removing the solvent by rotary evaporation, and then vacuum drying, a mixture doped with different concentrations of anions and cations is obtained. The tetrafluoroborate-based quaternary ammonium salt plastic crystal obtained by the above method, after introducing anions and cations, can improve the conductivity of the organic ionic plastic crystal through internal conduction, providing a possibility for developing solid electrolytes with high conductivity.

[0006] The main mechanism of this application is as follows: the quaternary ammonium salt plastic crystals of tetrafluoroborate have low electrical conductivity, and the maximum conductivity is 8.5 × 10 at the highest temperature. -8 S cm -1 However, due to the unique properties of tetrafluoroborate-based quaternary ammonium salt plastic crystals, during the transformation from the solid phase to the plastic crystal phase, molecules rotate, and defects within the spatial system increase, which can promote the transfer of dopant ions and improve the ion conduction ability of the plastic crystal. After doping tetrafluoroborate-based quaternary ammonium salt plastic crystals with the corresponding quaternary ammonium chloride and LiBF4 respectively, due to Cl... - Li + The small size allows for rapid movement within defects, promoting ion migration. Furthermore, when the corresponding quaternary ammonium chloride and LiBF4 are simultaneously doped into the tetrafluoroborate-based quaternary ammonium salt plastic crystal, Cl- is introduced into the matrix. - and Li + The combined action of cations and anions enhances migration ability and improves ionic conductivity.

[0007] The specific technical solution of the present invention is as follows:

[0008] The inventors first provided an organic ionic plastic crystal that facilitates the conduction of cations and anions. The raw material is an organic ionic plastic crystal, specifically a tetrafluoroborate quaternary ammonium salt plastic crystal, and its structural formula is as follows:

[0009]

[0010] The aforementioned ductile crystals are modified by doping, with the dopant being anionic dopant, cationic dopant, or a mixture thereof;

[0011] Specifically, tetrafluoroborate quaternary ammonium salt plastic crystals can be selected from dimethyl diethyl tetrafluoroborate ammonium ([N... 1122 ]BF4), trimethylethyltetrafluoroborate ammonium ([N 1112 ]BF4), tetraethylammonium tetrafluoroborate ([N 2222 One of the BF4),

[0012] The anionic dopant used is the quaternary ammonium chloride corresponding to the above-mentioned tetrafluoroborate quaternary ammonium salt plastic crystals, namely dimethyl diethyl ammonium chloride ([N... 1122 ]Cl), Trimethylethylammonium chloride ([N 1112 Cl), tetraethylammonium chloride ([N) 2222 The cationic dopants used are all lithium tetrafluoroborate (LiBF4), and their structural formulas are as follows:

[0013]

[0014] Since the conductivity of organic ionic plastic crystals is affected by the concentration of dopant, neither too high nor too low concentration can effectively improve the conductivity. The amount of dopant should account for 5-30% of the total molar amount of dopant and tetrafluoroborate quaternary ammonium salt plastic crystal.

[0015] Organic ionic plastic crystals modified with the above-mentioned dopants have the following characteristics:

[0016] After the addition of dopants, the tetrafluoroborate quaternary ammonium salt plastic crystals become softer and less prone to breakage under pressure after being pressed. Compared with pure tetrafluoroborate quaternary ammonium salt plastic crystals, the conductivity can be increased by up to about 2.7 orders of magnitude, which can reach the practical level of electrochemical devices.

[0017] In addition, the inventors also provided a method for preparing the above-mentioned organic ionic plastic crystals that facilitate the conduction of cations and anions, the specific steps of which are as follows:

[0018] Step (1): Under an argon atmosphere, weigh a certain mass of tetrafluoroborate quaternary ammonium salt and put it into a flask. Add an appropriate amount of acetonitrile to dissolve it. The mass ratio of acetonitrile to tetrafluoroborate quaternary ammonium salt is 6:1-8:1.

[0019] Step (2): Under an argon atmosphere, weigh out 5-30% of the corresponding quaternary ammonium chloride, which accounts for 5-30% of the total molar amount of tetrafluoroborate quaternary ammonium salt and quaternary ammonium chloride, and dissolve it in acetonitrile. The mass ratio of acetonitrile to quaternary ammonium chloride is 8:1-10:1. Use a dropper to take small amounts of the acetonitrile solution containing quaternary ammonium chloride and add it to the above acetonitrile solution containing tetrafluoroborate quaternary ammonium salt, and stir.

[0020] Step (3): Under an argon atmosphere, weigh 5-30% of the total molar amount of lithium tetrafluoroborate, which is a quaternary ammonium salt of tetrafluoroborate and lithium tetrafluoroborate. Dissolve it in acetonitrile. The mass ratio of acetonitrile to lithium tetrafluoroborate is 5:1-7:1. Use a dropper to take small amounts of the acetonitrile solution containing lithium tetrafluoroborate and add it to the above acetonitrile solution containing the quaternary ammonium salt of tetrafluoroborate. Stir.

[0021] Step (4): Under an argon atmosphere, weigh out 5-30% of the corresponding quaternary ammonium chloride and lithium tetrafluoroborate, which account for 5-30% of the total molar amount of tetrafluoroborate quaternary ammonium salt, corresponding quaternary ammonium chloride and lithium tetrafluoroborate, respectively, and dissolve them in acetonitrile. The mass ratio of acetonitrile to quaternary ammonium chloride is 8:1-10:1, and the mass ratio of acetonitrile to lithium tetrafluoroborate is 5:1-7:1. Use a dropper to take small amounts of the acetonitrile solution containing quaternary ammonium chloride and lithium tetrafluoroborate, and add it to the above acetonitrile solution containing tetrafluoroborate quaternary ammonium salt, and stir.

[0022] Steps 2-4 above respectively prepare anion-doped plastic crystals, cation-doped plastic crystals, and mixed anion-cation-doped plastic crystals.

[0023] The dopants and tetrafluoroborate quaternary ammonium salts used above are all reagent grade. They do not produce impurities after dissolution and mixing, and no further purification is required.

[0024] Step (5): Stir thoroughly for 4 hours under an argon atmosphere. After the reaction is complete, remove the acetonitrile by rotary evaporation and dry under ultra-vacuum at 70°C.

[0025] All the above processes of adding dopants were carried out at room temperature.

[0026] Preferably, in step (2), the number of moles of the added quaternary ammonium chloride accounts for 20% of the total number of moles of tetrafluoroborate quaternary ammonium salt and quaternary ammonium chloride;

[0027] Preferably, in step (3), the number of moles of lithium tetrafluoroborate added accounts for 20% of the total number of moles of tetrafluoroborate quaternary ammonium salt and lithium tetrafluoroborate;

[0028] Preferably, in step (4), the molar number of the added quaternary ammonium chloride and lithium tetrafluoroborate accounts for 20% of the total molar number of tetrafluoroborate quaternary ammonium salt, quaternary ammonium chloride and lithium tetrafluoroborate, respectively.

[0029] The inventors also provide a method for testing the conductivity of the above-mentioned organic ionic plastic crystals that facilitate the conduction of cations and anions, comprising the following steps:

[0030] Step (1): Under an argon atmosphere, weigh 100 mg of the sample, grind it into powder, and place it into an insulating compression mold with a diameter of 10 mm;

[0031] Step (2): Place an insulating plate at the top and bottom of the mold, put it into the three-column double-layer transfer fixture, put the transfer fixture into the tablet press, press the pressure handle to raise the pressure to 5MPa, maintain this pressure for 5 minutes, tighten the screws on the top of the transfer fixture again, release the pressure, take out the transfer fixture, and the sample in the mold is pressed into a round sheet with a thickness of 1mm.

[0032] Step (3): Place the entire set of fixtures for fixing the mold into the atmosphere protection temperature change device, introduce argon gas, and perform AC impedance testing when the temperature inside the device reaches the set temperature.

[0033] Since an insulating plate is placed on both the top and bottom of the mold, it will not affect the conductivity.

[0034] The mold used has high hardness, corrosion resistance, and toughness, and the contact surface with the sample has a high degree of smoothness. The pressed sheet is subjected to uniform force and has a smooth surface. After the sample is loaded in an argon atmosphere, it does not need to be transferred again, avoiding the possibility of the sample coming into contact with air and keeping the sample in a dry state.

[0035] The insulating pressing mold was purchased from Nobadi Materials Technology Co., Ltd., the atmosphere protection temperature change device is a prior patent of the applicant, with patent number ZL202121265495.2, and the AC impedance testing instrument is a Shanghai Chenhua CHI660E electrochemical workstation; the inventor will not elaborate on the specific structure.

[0036] Compared with the prior art, the advancements of this application are reflected in:

[0037] Existing reports have found that some organic ionic plastic crystals can conduct cations (such as Li). + Na + ), and organic ionic plastic crystal dimethyl diethylammonium camphor sulfonate ([N) has also been found in the earlier application. 1122 [CSA]) can conduct anions (Cl) - F - However, it cannot conduct cations. The organic ionic plastic crystal of this invention, on the other hand, can conduct anions (Cl...). - It can also conduct cations (Li). + Furthermore, it can simultaneously conduct cations and anions (Cl). - Li + );

[0038] Simultaneously doping the matrix with cations and anions (Cl) - Li + After that, the conductivity can reach up to 10. -6 S cm -1 The conductivity at room temperature is increased by about 3.5 orders of magnitude compared to the pure product, which makes it possible for organic ionic plastic crystals to become safe and efficient solid conductors;

[0039] The tetrafluoroborate quaternary ammonium salt plastic crystal selected in this invention has excellent mechanical elasticity after doping. It can be pressed into sheets under very low pressure. The sample is very soft and can be easily deformed under strong pressure but is not easy to break. Attached Figure Description

[0040] Figure 1 It is an organic ionic plastic crystal, tetraethylammonium tetrafluoroborate ([N 2222 [BF4] Conductivity vs. Temperature;

[0041] Figure 2 For doping with 20 mol% Cl - Organic ionic plastic crystals of tetraethyltetrafluoroborate ammonium ([N 2222 [BF4] Conductivity vs. Temperature;

[0042] Figure 3 For 20 mol% Li doping + Organic ionic plastic crystals of tetraethyltetrafluoroborate ammonium ([N 2222 [BF4] Conductivity vs. Temperature;

[0043] Figure 4 To simultaneously dope 20 mol% Cl - Li + Organic ionic plastic crystals of tetraethyltetrafluoroborate ammonium ([N 2222 [BF4] Conductivity vs. Temperature;

[0044] from Figure 1 It can be seen from this that the organic ionic plastic crystal tetraethyltetrafluoroborate ammonium ([N) 2222 The conductivity of BF4 increases with increasing temperature, reaching 8.5 × 10⁻⁶ at 90 °C. -8 S cm -1 ;

[0045] Doped with 20 mol% tetraethylammonium chloride ([N 2222 Organic ionic plastic crystals of tetraethyltetrafluoroborate ([N)Cl) 2222 Compared to the pure product, the conductivity of BF4 increased by approximately 2.7 orders of magnitude, reaching 4.1 × 10⁻⁶. -5 S cm -1 ,like Figure 2 ;

[0046] Organic ionic plastic crystal tetraethylammonium tetrafluoroborate ([N) doped with 20 mol% lithium tetrafluoroborate (LiBF4) 2222 Compared to the pure product, the conductivity of BF4 is increased by approximately 2.5 orders of magnitude, reaching a maximum of 4.1 × 10⁻⁶. -6 S cm -1 ,like Figure 3 ;

[0047] Simultaneously doped with 20 mol% tetraethylammonium chloride ([N 2222Organic ionic plastic crystals of tetraethylammonium tetrafluoroborate ([NCl) and lithium tetrafluoroborate (LiBF4)) 2222 Compared to the pure product, BF4 exhibits an increase in conductivity of approximately 2.7 orders of magnitude, reaching a maximum of 1.0 × 10⁻⁶. -5 S cm -1 ,like Figure 4 .

[0048] Overall, after doping with anions and cations, the organic ionic plastic crystal tetraethyltetrafluoroborate ammonium ([N) 2222 The conductivity of BF4 was significantly improved, especially when it was simultaneously doped with 20 mol% of anions and cations (Cl). - Li + After that, the conductivity can reach 10. -5 S cm -1 It is approaching the level of practical electrochemical devices. Detailed Implementation

[0049] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention. The concentrations in the following embodiments refer to mass concentrations.

[0050] Next, we will discuss one type of tetrafluoroborate quaternary ammonium salt plastic crystal, namely the organic ionic plastic crystal tetraethylammonium tetrafluoroborate ([N... 2222 Using BF4 as the matrix, tetraethylammonium chloride ([N) is added to it. 2222 The examples of ]Cl) and lithium tetrafluoroborate (LiBF4) are described in detail.

[0051] Example 1

[0052] Tetraethylammonium tetrafluoroborate ([N) 2222 The preparation method of BF4 is shown in the following reaction equation:

[0053]

[0054] The specific steps are as follows:

[0055] Under ice-water bath conditions, a 50% aqueous solution of tetrafluoroboric acid (2 g, 11.4 mmol) was diluted with water to a concentration of 25%, and then slowly added dropwise to a 25% aqueous solution of tetraethylammonium hydroxide (6.71 g, 11.4 mmol) in an equimolar ratio. The reaction was stirred in an ice-water bath for at least 8 hours. After the reaction was completed, the water was removed by rotary evaporation to obtain the crude product.

[0056] Acetonitrile was slowly added dropwise to the crude product at room temperature to obtain a saturated solution. Ethyl acetate was then added dropwise to the solution until no more white solid precipitated. The volume ratio of ethyl acetate to acetonitrile was 2:1 to 4:1. The solution was filtered and dried under ultra-vacuum at 70°C for 48 hours to obtain tetraethylammonium tetrafluoroborate with a purity of 99%.

[0057] The method for preparing tetraethyltetrafluoroborate ammonium involves few steps, is simple to operate, and has a high yield with a purity of 99%, meeting experimental requirements. After vacuum drying, it can be directly used for conductivity measurement and sample doping.

[0058] Example 2

[0059] Preparation method of anion-doped tetraethyltetrafluoroborate ammonium:

[0060] Under an argon atmosphere, a certain mass of tetraethylammonium tetrafluoroborate (300 mg) was weighed and placed in a round-bottom flask. Acetonitrile was added to dissolve it completely, with a mass ratio of acetonitrile to tetraethylammonium tetrafluoroborate of 6:1-8:1. Separately, 20% of the total molar amount of tetraethylammonium chloride and tetraethylammonium tetrafluoroborate (58.4 mg) of tetraethylammonium chloride was added to acetonitrile to dissolve it, with a mass ratio of acetonitrile to tetraethylammonium chloride of 8:1-10:1. Small, repeated drops of the acetonitrile solution containing tetraethylammonium chloride were added to the above acetonitrile solution containing tetraethylammonium tetrafluoroborate. The mixture was stirred thoroughly for 4 hours under an argon atmosphere. After the reaction was completed, the acetonitrile was removed by rotary evaporation, and the solution was dried under ultra-vacuum at 70°C for 48 hours.

[0061] Example 3

[0062] Preparation method of cation-doped tetraethyltetrafluoroborate ammonium:

[0063] Under an argon atmosphere, a certain mass of tetraethylammonium tetrafluoroborate (300 mg) was weighed and placed in a round-bottom flask. Acetonitrile was added to dissolve it completely, with a mass ratio of acetonitrile to tetraethylammonium tetrafluoroborate of 6:1-8:1. Separately, lithium tetrafluoroborate (32.4 mg), accounting for 20% of the total molar amount of lithium tetrafluoroborate and tetraethylammonium tetrafluoroborate, was dissolved in acetonitrile, with a mass ratio of acetonitrile to lithium tetrafluoroborate of 5:1-7:1. Small, repeated drops of the acetonitrile solution containing lithium tetrafluoroborate were added to the above acetonitrile solution containing tetraethylammonium tetrafluoroborate. The mixture was thoroughly mixed and stirred for 4 hours under an argon atmosphere. After the reaction was completed, the acetonitrile was removed by rotary evaporation, and the solution was dried under ultra-vacuum at 70°C for 48 hours.

[0064] Example 4

[0065] Preparation method of tetraethyltetrafluoroborate ammonium doped with both cations and anions

[0066] Under an argon atmosphere, a certain mass of tetraethylammonium tetrafluoroborate (300 mg) was weighed and placed in a round-bottom flask. Acetonitrile was added to dissolve it completely, with a mass ratio of acetonitrile to tetraethylammonium tetrafluoroborate of 6:1-8:1. Separately, tetraethylammonium chloride (77.1 mg) and lithium tetrafluoroborate (42.8 mg), accounting for 20% of the total molar amounts of tetraethylammonium chloride, lithium tetrafluoroborate, and tetraethylammonium tetrafluoroborate, were weighed and dissolved in acetonitrile, with a mass ratio of acetonitrile to tetraethylammonium chloride of 8:1-10:1 and a mass ratio of acetonitrile to lithium tetrafluoroborate of 5:1-7:1. Small, repeated applications of the acetonitrile solutions containing tetraethylammonium chloride and lithium tetrafluoroborate were added to the above acetonitrile solution containing tetraethylammonium tetrafluoroborate. The mixture was thoroughly mixed and stirred for 4 hours under an argon atmosphere. After the reaction was completed, the solution was rotary evaporated to remove the acetonitrile and then dried under ultra-vacuum at 70°C for 48 hours.

[0067] Example 5

[0068] The conductivity testing method for organic ionic plastic crystals that facilitate the conduction of cations and anions is as follows:

[0069] Under an argon atmosphere, 100 mg of sample was weighed, ground into powder, and placed into an insulating die with a diameter of 10 mm. An insulating plate was placed at the top and bottom of the die. The die was then placed in a three-column, double-layer transfer fixture, and the top screw was tightened. The fixture was placed in a tablet press, and the pressure was increased to 5 MPa. This pressure was maintained for 5 minutes. The top screw of the transfer fixture was tightened again to maintain the pressure. The pressure was then released, and the transfer fixture was removed. The sample inside the die was pressed into a circular sheet with a thickness of approximately 1 mm. The entire fixture holding the die was placed in a temperature-controlled atmosphere device, and argon gas was introduced. Once the temperature inside the device reached the set temperature, an AC impedance test was performed. When measuring the resistance at different temperatures, the sample was held at the set temperature for 30 minutes before testing to ensure the temperature of the testing system.

[0070] After the test is completed, ZView 2.0 software is used to fit the sample to obtain the resistance at the test temperature. The conductivity is calculated according to the formula, and the relationship between conductivity and temperature is plotted.

[0071] By comparing the conductivity diagrams, it can be seen that organic ionic plastic crystals ([N) 2222 BF4) in doped with anions and cations (Cl) - Li + After that, the conductivity was significantly improved:

[0072] Figure 1 It is a pure organic ionic plastic crystal, tetraethylammonium tetrafluoroborate ([N 2222 The graph shows the relationship between the conductivity of BF4 and temperature. The conductivity increases with increasing temperature, reaching its maximum at 90℃, at 8.5 × 10⁻⁶.-8 S cm -1 Towards organic ionic plastic crystals ([N 2222 [BF4] doped with tetraethylammonium chloride ([N 2222 After Cl), anion (Cl) was introduced. - ), and pure [N 2222 Compared to BF4, its conductivity at 90℃ is 4.1 × 10⁻⁶. -5 S cm -1 Increased by about 3 orders of magnitude ( Figure 2 After doping with lithium tetrafluoroborate (LiBF4), cations (Li) are introduced. + The highest conductivity is 4.1 × 10⁻⁶. -6 S cm -1 This is an increase of approximately three orders of magnitude. Figure 3 ). Towards organic ionic plastic crystals ([N 2222 BF4) is simultaneously doped with anions and cations ([N 2222 Cl, LiBF4), with a conductivity reaching up to 4.5 × 10⁻⁶. -7 S cm -1 ( Figure 4 ).

[0073] As the temperature increases, pure organic ionic plastic crystal tetraethylammonium tetrafluoroborate ([N... 2222 [BF4] and [N] doped with anions and cations respectively 2222 The overall trend of BF4 increases with increasing temperature. However, the doping with tetraethylammonium chloride ([N...)... 2222 Organic ionic plastic crystals of tetraethylammonium tetrafluoroborate ([NCl) and lithium tetrafluoroborate (LiBF4)) 2222 [N]BF4), at 90℃, is only slightly more ductile than organic ionic plastic crystals doped only with lithium tetrafluoroborate (LiBF4) ([N] 2222 The conductivity of BF4 is 7 × 10⁻⁶ higher. -7 S cm -1 However, at room temperature, organic ionic plastic crystals ([N) doped with both cations and anions (N) 2222 BF4) is more ductile than pure organic ionic plastic crystals ([N) 2222 The conductivity of [BF4] was increased by about 3.5 orders of magnitude, even compared to that of tetraethylammonium chloride ([N]). 2222 Organic ionic plastic crystals of Cl ([N) 2222 The conductivity of BF4 is even higher, reaching 4.5 × 10⁻⁶. -7 S cm -1The simultaneous conduction of cations and anions in the plastic crystal solves the problem of low ionic conductivity of organic ionic plastic crystals at room temperature, and provides a possibility for the application of plastic crystals in solid electrolytes.

[0074] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An organic ionic plastic crystal that facilitates the conduction of cations and anions, characterized in that: The raw material is a tetrafluoroborate quaternary ammonium salt plastic crystal, which is selected from one of dimethyldiethyltetrafluoroborate, trimethylethyltetrafluoroborate, and tetraethyltetrafluoroborate. The plastic crystal is modified by doping to obtain an organic ionic plastic crystal that facilitates the conduction of anions and cations. The dopant is a mixture of anionic and cationic dopant. The anionic dopant used is the quaternary ammonium chloride corresponding to the above-mentioned tetrafluoroborate quaternary ammonium salt plastic crystals, namely dimethyldiethylammonium chloride, trimethylethylammonium chloride, and tetraethylammonium chloride. The cationic dopant used is lithium tetrafluoroborate.

2. The method for preparing the organic ionic plastic crystal that facilitates the conduction of anions and cations as described in claim 1, characterized in that, The specific steps are as follows: Step (1): Under an argon atmosphere, weigh a certain mass of tetrafluoroborate quaternary ammonium salt and put it into a flask. Add an appropriate amount of acetonitrile to dissolve it. The mass ratio of acetonitrile to tetrafluoroborate quaternary ammonium salt is 6:1-8:

1. Step (2): Under an argon atmosphere, weigh out 20% of the total molar amount of the corresponding quaternary ammonium salt, the corresponding quaternary ammonium chloride, and lithium tetrafluoroborate, and dissolve them in acetonitrile. The mass ratio of acetonitrile to quaternary ammonium chloride is 8:1-10:1, and the mass ratio of acetonitrile to lithium tetrafluoroborate is 5:1-7:

1. Use a dropper to take small amounts of the acetonitrile solution containing quaternary ammonium chloride and lithium tetrafluoroborate, and add them to the above acetonitrile solution containing quaternary ammonium salt of tetrafluoroborate. Stir. Step (3): Stir thoroughly for 4 hours under an argon atmosphere. After the reaction is complete, remove the acetonitrile by rotary evaporation and dry under ultra-vacuum at 70°C.

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