A method and system for testing graphene dispersibility

Abstract

The application provides a graphene dispersibility testing method and system, which comprises the following steps: taking palygorskite for grinding, dispersing the palygorskite in deionized water to form a precursor solution, and performing a resistivity test; adding graphene into the precursor solution, respectively stirring and homogenizing to make the graphene loaded on the palygorskite to form a sol; performing a resistivity test on the obtained sol; correcting the resistivity of the precursor solution according to the relationship between the concentration and the resistivity of the sol; constructing a dispersibility and resistivity data model by using the relationship between the concentration and the resistivity of the sol to obtain graphene dispersibility data. According to the application, the graphene is loaded on the palygorskite, the strip structure layer and the channel in the structure of the palygorskite provide positions for loading the graphene, the palygorskite has good adsorbability and specific surface area, and the loaded graphene is dispersed in the deionized water by means of the good dispersibility of the palygorskite, and the resistivity is used to obtain the dispersibility data of the graphene dispersion.

Description

Technical Field

[0001] This invention relates to the field of graphene dispersion technology, specifically to a method and system for testing the dispersibility of graphene. Background Technology

[0002] Graphene is a two-dimensional material composed of carbon atoms, exhibiting a honeycomb-like structure. Each graphene is only one atom thick and possesses many unique properties, making it a hot research topic in the field of materials science.

[0003] In the application of graphene, due to its composition of a six-membered benzene ring with stable bonds, graphene exhibits high chemical stability and an inert surface, resulting in weak interaction with other media. Furthermore, strong intermolecular forces exist between the graphene sheets, causing them to easily stack together and be difficult to disperse. This makes it difficult to dissolve in solvents and even more difficult to uniformly composite with other organic or inorganic materials, hindering further development of graphene. Existing technologies typically rely on AFM (Atomic Force Microscope), TEM (Transmission Electron Microscope), and thin-film conductivity testing, requiring specialized equipment that is difficult to implement and demands high levels of expertise, making it inconvenient to obtain dispersion data for graphene dispersions. Therefore, this invention researches and designs a method and system for testing the dispersibility of graphene. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the inconvenience of graphene dispersion testing in the prior art, thereby providing a graphene dispersion testing method and system.

[0005] To address the above problems, this invention provides a method for testing the dispersibility of graphene, comprising:

[0006] S1: Grind palygorskite, disperse it in deionized water to form a precursor solution, and perform resistivity testing;

[0007] S2: Add graphene to the precursor solution, stir and homogenize to load the graphene onto palygorskite to form a sol;

[0008] S3: Perform resistivity testing on the obtained sol;

[0009] S4: Correct the relationship between the concentration and resistivity of the sol by adjusting the resistivity of the precursor solution;

[0010] S5: Construct a dispersibility and resistivity data model using the relationship between the concentration and resistivity of the sol, and obtain graphene dispersibility data using the dispersibility and resistivity data model.

[0011] Preferably, in step S3, the obtained sol is injected into test tubes of different specifications and the corresponding test tubes are filled. The test device is connected to the electrodes on both sides of the corresponding test tube. The test device is adjusted to turn on, and the corresponding variable resistors are adjusted to appropriate positions. The corresponding voltage value, current value, variable resistance value and specification data of the corresponding test tube are read from the test device. The resistivity of the sol under different specifications of test tubes is calculated to obtain the resistivity of the sol.

[0012] Preferably, the resistivity ρ of the sol under the corresponding test tube is calculated. i for:

[0013]

[0014] The resistivity ρ of the sol is:

[0015]

[0016] Among them, U i For the corresponding voltmeter reading, I i R is the corresponding ammeter reading. 变i S corresponds to the variable resistance value in the circuit. i L is the cross-sectional area of ​​the corresponding test tube. i The length of the corresponding test tube is given, ρ is the resistivity of the sol, and i = 1, 2, and 3 represent the first test tube, the second test tube, and the third test tube, respectively.

[0017] Preferably, the amounts of palygorskite, deionized water, and graphene added are in a mass ratio of 0.5–3:90–100:0.2–1.

[0018] Preferably, in step S2, the stirring method is ultrasonic stirring, wherein when adding graphene to the precursor solution, the graphene is added while stirring for 5-10 minutes.

[0019] The homogenization is performed in a homogenizer for 15 to 20 minutes.

[0020] Preferably, in step S4, resistivity data models of precursor solutions at different concentrations, resistivity data models of sols, and dispersibility data models of precursor solutions at different concentrations are established respectively. The resistivity data model of the sol is corrected by the resistivity data model of the precursor solutions at the same concentration to obtain graphene dispersions and resistivity data models at different concentrations.

[0021] Preferably, in S5:

[0022] By coupling the obtained data models of graphene dispersions and resistivity at different concentrations with the data models of precursor solutions at different concentrations, a data model of dispersibility and resistivity is obtained.

[0023] Based on the dispersibility and resistivity data model, the dispersibility data of graphene in sol is obtained by obtaining the resistivity of the corresponding graphene dispersion.

[0024] This invention also provides a graphene dispersibility testing system, which employs the graphene dispersibility testing method described in any of the preceding claims, comprising:

[0025] The grinding module grinds palygorskite;

[0026] The ultrasonic module stirs the graphene when the precursor solution formed after grinding is added.

[0027] The homogenization module homogenizes the precursor solution of the mixed graphene to form a sol;

[0028] The testing device measures the resistivity of test tubes of different specifications to obtain the resistivity of the sol.

[0029] The processing module obtains graphene dispersion data through the resistivity of the sol.

[0030] Preferably, the testing device is provided in three sets, each of which includes a DC power supply. The two poles of the DC power supply are respectively connected to a test circuit. The test circuit is respectively provided with a test switch, an ammeter, a voltmeter, and a variable resistor. Electrodes are respectively provided between the ends of the test circuit away from the DC power supply. A first test tube, a second test tube, and a third test tube are respectively provided between the two electrodes of the testing device. The two electrodes extend into the two ends of the first test tube, the second test tube, and the third test tube, respectively.

[0031] Preferably, the first test tube, the second test tube, and the third test tube are all cylindrical in shape, and the specifications of the first test tube, the second test tube, and the third test tube are different.

[0032] The graphene dispersibility testing method and system provided by this invention have the following beneficial effects:

[0033] 1. This invention loads graphene onto palygorskite to form a target sol, thereby dispersing graphene in a dispersion system using palygorskite. The resistivity of the resulting sol is then measured, and the dispersion data of graphene is obtained by comparing the resistivity data of the loaded and unloaded graphene.

[0034] 2. The present invention also loads graphene onto palygorskite, which has a better dispersion effect in deionized water than graphene. At the same time, there is no change in chemical properties during the loading of graphene onto palygorskite. The banded structural layers and channels in the palygorskite structure provide a location for loading graphene, which has good adsorption and specific surface area. The loaded graphene is dispersed in deionized water with the help of the good dispersibility of palygorskite.

[0035] 3. This invention also establishes resistivity data models for precursor solutions at different concentrations, resistivity data models for sols, and dispersibility data models for precursor solutions at different concentrations by measuring the resistivity of the loaded sol. The resistivity data model of the sol is corrected by the resistivity data model of the precursor solution at the same concentration to obtain graphene dispersion and resistivity data models at different concentrations. The obtained graphene dispersion and resistivity data models at different concentrations are coupled with the dispersibility data models of precursor solutions at different concentrations to obtain dispersibility and resistivity data models, thereby obtaining graphene dispersibility data. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the graphene dispersibility testing method of the present invention;

[0037] Figure 2 This is a schematic diagram of the graphene dispersibility testing system of the present invention;

[0038] Figure 3 This is a schematic diagram of the installation structure of the testing device of the present invention.

[0039] The reference numerals in the attached figures are as follows:

[0040] 1. DC power supply; 2. Test switch; 3. Ammeter; 4. Voltmeter; 5. Electrodes; 6. Variable resistor. Detailed Implementation

[0041] like Figure 1-3 As shown, the present invention provides a method for testing the dispersibility of graphene, comprising:

[0042] S1: Grind palygorskite, disperse it in deionized water to form a precursor solution, and perform resistivity testing;

[0043] S2: Add graphene to the precursor solution, stir and homogenize to load the graphene onto palygorskite to form a sol;

[0044] S3: Perform resistivity testing on the obtained sol;

[0045] S4: Correct the relationship between the concentration and resistivity of the sol by adjusting the resistivity of the precursor solution;

[0046] S5: Construct a dispersibility and resistivity data model using the relationship between the concentration and resistivity of the sol, and obtain graphene dispersibility data using the dispersibility and resistivity data model. For example... Figure 1-3 As shown, a method for testing the dispersibility of graphene involves grinding palygorskite into a powder of 160-200 mesh, dividing it into multiple groups, and dispersing them in deionized water at different mass ratios to form precursor solutions. The concentrations of the precursor solutions are calculated for each group, and their resistivity at different concentrations is measured. Then, graphene is added to the precursor solutions using ultrasonic stirring for 5-10 minutes to ensure the graphene is incorporated into the precursor solutions. The precursor solution is mixed with multiple groups of palygorskite, water, and graphene in a mass ratio of 0.5–3:90–100:0.2–1. The solution is then homogenized using a homogenizer to micronize and homogenize the graphene, improving its distribution and allowing it to interact with the banded channels within the palygorskite structure to provide a loading surface for the graphene, ultimately yielding the target sol. Graphene exhibits poor dispersibility in deionized water, while palygorskite demonstrates better dispersibility in deionized water compared to graphene. Furthermore, no chemical changes occur during the loading of graphene onto palygorskite. The banded structural layers and channels in the palygorskite structure provide sites for the loaded graphene, exhibiting good adsorption and specific surface area. The loaded graphene, thanks to the good dispersibility of palygorskite, disperses well in deionized water. By measuring the resistivity data of the precursor solution, sol, and dispersibility data of the precursor solution at multiple concentrations, corresponding data models were constructed. The resistivity data of the precursor solution at multiple concentrations (blank control) was used to correct the resistivity data of the sol at the corresponding concentrations. A dispersibility and resistivity data model was constructed using the relationship between sol concentration and resistivity. The dispersion data of the graphene dispersion can be obtained by determining the concentration of graphene dispersed in the sol. This allows for the acquisition of dispersibility data simply by measuring the resistivity of the corresponding dispersion, making the entire testing method simple and highly operable.

[0047] In some embodiments, in step S3, the obtained sol is injected into test tubes of different specifications and the corresponding test tubes are filled. The test device is connected to the electrodes on both sides of the corresponding test tube. The test device is adjusted to turn on, and the corresponding variable resistors are adjusted to appropriate positions. The corresponding voltage value, current value, variable resistance value and specification data of the corresponding test tube are read from the test device. The resistivity of the sol under different specifications of test tubes is calculated to obtain the resistivity of the sol.

[0048] Specifically, such as Figure 1-3As shown, by placing the sol into test tubes of different specifications and filling the corresponding test tubes, the test device is connected to the electrodes on both sides of the corresponding test tube. The test device is turned on and the variable resistor is adjusted. By obtaining the corresponding voltage value, variable resistance value, current value on the test device and the specification data of the corresponding test tube, the resistivity of the test tube under different specifications is calculated to obtain the resistivity of the sol, so as to eliminate the error of the influence on the resistivity. At the same time, the test method of the precursor solution can also use the same test method as the sol resistivity.

[0049] In some implementations, the resistivity ρ of the sol under the corresponding test tube is calculated. i for:

[0050]

[0051] The resistivity ρ of the sol is:

[0052]

[0053] Among them, U i For the corresponding voltmeter 4 reading, I i For the corresponding ammeter 3 reading, R 变i For the corresponding variable resistor 6 value in the circuit, S i L is the cross-sectional area of ​​the corresponding test tube. i The length of the corresponding test tube is given, ρ is the resistivity of the sol, and i = 1, 2, and 3 represent the first test tube, the second test tube, and the third test tube, respectively.

[0054] Specifically, such as Figure 1-3 As shown, the cross-sectional area and length of the first, second, and third test tubes are obtained by using three sets of test tubes of different specifications. After they are filled with sol, they are connected to the test device and test circuit through electrodes at both ends to obtain multiple sets of test data. The data are then averaged to obtain the sol resistivity data at the corresponding concentration, so as to eliminate the error caused by the influence of resistivity.

[0055] In some embodiments, the amounts of palygorskite, deionized water, and graphene added are in a mass ratio of (0.5–3):(90–100):(0.2–1).

[0056] Specifically, such as Figure 1-3 As shown, the amounts of palygorskite, deionized water, and graphene added are in a mass ratio of 0.5–3:90–100:0.2–1. This ensures that the palygorskite forms a uniform dispersion in the deionized water, and that the addition of graphene stabilizes the overall dispersion, providing a loading site for the added graphene to facilitate subsequent dispersibility testing.

[0057] In some embodiments, in step S2, the stirring method is ultrasonic stirring, wherein when adding graphene to the precursor solution, the graphene is added while stirring for 5-10 minutes.

[0058] The homogenization is performed in a homogenizer for 15 to 20 minutes.

[0059] Specifically, such as Figure 1-3 As shown, in step S2, the stirring method is ultrasonic stirring. Ultrasonic stirring relies on an ultrasonic stirrer, utilizing the explosion of tiny bubbles and the shearing action of the liquid flow generated by high-frequency sound waves to mix and disperse the graphene. Adding graphene to the entire precursor solution without contact prevents the graphene from agglomerating due to its structure, effectively breaking up the graphene particles and making it easier to disperse in the precursor solution. Simultaneously, when adding graphene to the precursor solution, the ultrasonic stirring rate is set to three gradients while stirring. Initially, when adding graphene, the ultrasonic stirring frequency... The frequency was initially set at 35 kHz. After adding more than half of the target amount of graphene, the frequency was gradually increased to 61 kHz and ultrasonic stirring continued until all the graphene was added. Then, the frequency was gradually restored to 35 kHz to disperse the graphene in the precursor solution. The solution was then homogenized for 15–20 minutes using a homogenizer. This homogenization process micronized and homogenized the graphene in the precursor solution, improving its uniform distribution and allowing it to interact with the banded channels within the palygorskite structure to provide a loading location for the graphene, ultimately yielding the target sol.

[0060] In some embodiments, in step S4, resistivity data models of precursor solutions at different concentrations, resistivity data models of sols, and dispersibility data models of precursor solutions at different concentrations are established respectively. The resistivity data model of the sol is corrected by the resistivity data model of the precursor solutions at the same concentration to obtain graphene dispersions and resistivity data models at different concentrations.

[0061] Specifically, such as Figure 1-3As shown, during the graphene dispersibility test, resistivity data models for precursor solutions, sols, and dispersibility data of precursor solutions at different concentrations were established using dispersibility and resistivity data at different concentrations. By modifying the resistivity data model of the sol with the resistivity data model of the precursor solution at the same concentration, a graphene dispersion and resistivity data model was obtained, with the sol concentration as the independent variable and the resistivity of graphene in the sol as the dependent variable. This model clearly reflects the resistivity data of graphene in the entire dispersion system. Based on this model, in subsequent tests, only the resistivity of the corresponding sol needs to be used to obtain the dispersibility data of graphene in the sol, making it convenient to test the dispersibility of graphene.

[0062] In some implementations, the coupling is:

[0063] In S5:

[0064] By coupling the obtained data models of graphene dispersions and resistivity at different concentrations with the data models of precursor solutions at different concentrations, a data model of dispersibility and resistivity is obtained. Based on the data model of dispersibility and resistivity, the dispersibility data of graphene in the sol is obtained by obtaining the resistivity of the corresponding sol.

[0065] Specifically, such as Figure 1-3 As shown, a dispersion and resistivity data model is obtained by coupling a data model of graphene dispersion and resistivity at different concentrations with a data model of dispersion of precursor solution at different concentrations. This process utilizes coupling to establish the dispersion and resistivity data model. Specifically, the graphene dispersion and resistivity data model and the data model of dispersion of precursor solution at different concentrations are transformed using the same independent variable. Using the graphene dispersion and resistivity data model as the independent variable, a Fourier transform is performed on the data model of dispersion of precursor solution to obtain the coupled dispersion and resistivity data model. This overcomes the influence of graphene loading on the precursor solution, resulting in a resistivity and dispersion data model adapted to the graphene dispersion. This establishes a relationship between dispersion and resistivity for the graphene dispersion in the entire dispersion system, allowing the corresponding dispersion data to be obtained based on the resistivity. Based on the dispersion and resistivity data model, the dispersion data of graphene in the sol is obtained by obtaining the resistivity of the corresponding graphene dispersion.

[0066] This invention also provides a graphene dispersibility testing system, which employs the graphene dispersibility testing method described in any of the preceding claims, comprising:

[0067] The grinding module grinds palygorskite;

[0068] The ultrasonic module stirs the graphene when the precursor solution formed after grinding is added.

[0069] The homogenization module homogenizes the precursor solution of the mixed graphene to form a sol;

[0070] The testing device measures the resistivity of test tubes of different specifications to obtain the resistivity of the sol.

[0071] The processing module obtains graphene dispersion data based on the resistivity of the sol. For example... Figure 2-3 As shown, a graphene dispersion testing system uses a grinding module to grind palygorskite to improve its dispersion in deionized water. The ground palygorskite is then added to a container and ultrasonicated using an ultrasonic module. Simultaneously, graphene is added to disperse the graphene in the precursor solution. A homogenization module loads the graphene into the internal structure of the palygorskite, forming a sol. The testing module measures the resistivity of test tubes of different specifications to obtain the resistivity of the sol. Finally, a processing module obtains the processed graphene dispersion data, which can be processed and calculated by a host computer.

[0072] In some embodiments, the testing device is provided in three sets. Each testing device includes a DC power supply 1. The two poles of the DC power supply 1 are respectively connected to a testing circuit. The testing circuit is respectively provided with a test switch 2, an ammeter 3, a voltmeter 4, and a variable resistor 6. Electrodes 5 are respectively provided between the ends of the testing circuit away from the DC power supply 1. A first test tube, a second test tube, and a third test tube are respectively provided between the two electrodes 5 of the testing device. The two electrodes 5 extend into the two ends of the first test tube, the second test tube, and the third test tube, respectively.

[0073] Specifically, such as Figure 2-3 As shown, the testing device is set up with three sets. Each testing device includes a DC power supply 1. The two poles of the DC power supply 1 are respectively connected to the test circuit. The test circuit is controlled by the test switch 2, ammeter 3, voltmeter 4 and variable resistor 6, respectively, to obtain the current value, voltage value and resistance value of the variable resistor 6. The test circuit is connected to the electrodes 5 at both ends of the first test tube, the second test tube and the third test tube to perform resistivity testing. The first test tube, the second test tube and the third test tube are all set as separate units. Protective caps are set at both ends of the test tube, so that the protective caps are snapped into the two ends of the tube body of the first test tube, the second test tube and the third test tube respectively. The electrodes 5 pass through the two ends of the protective caps and are located on both sides of the protective caps. After the liquid to be tested is added into the first test tube, the second test tube and the third test tube, the test circuit is connected through the electrodes to facilitate subsequent testing.

[0074] In some embodiments, the first test tube, the second test tube, and the third test tube are all cylindrical in shape, and their specifications are different. Specifically, by setting the first test tube, the second test tube, and the third test tube to be cylindrical, with each having different specifications, the resistance value of the corresponding test tube is obtained by matching its cross-section and length with variable resistance, voltage, and current values. The resistance value of the sol is obtained by using the resistance values ​​of the test tubes with different specifications, thereby eliminating the influence of errors during the testing process.

[0075] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention. The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the protection scope of the present invention.

Claims

1. A method for testing the dispersibility of graphene, characterized in that, Includes the following steps: S1: Grind palygorskite, disperse it in deionized water to form a precursor solution, and perform resistivity testing; S2: Add graphene to the precursor solution, stir and homogenize to load the graphene onto palygorskite to form a sol; S3: Perform resistivity testing on the obtained sol; S4: Correct the relationship between the concentration and resistivity of the sol using the resistivity of the precursor solution; S5: Construct a dispersibility and resistivity data model using the relationship between the concentration and resistivity of the sol, and obtain graphene dispersibility data using the dispersibility and resistivity data model; In step S3, the obtained sol is injected into test tubes of different specifications and the corresponding test tubes are filled. The test device is connected to the electrodes on both sides of the corresponding test tube. The test device is adjusted to turn on and the corresponding variable resistor is adjusted to a suitable position. The corresponding voltage value, current value, variable resistance value and the specification data of the corresponding test tube are read from the test device. The resistivity of the sol under different specifications of test tubes is calculated to obtain the resistivity of the sol. Calculate the resistivity ρ of the sol under the corresponding test tube. i for: ; The resistivity ρ of the sol is: ; Among them, U i For the corresponding voltmeter reading, I i R is the corresponding ammeter reading. 变i S corresponds to the variable resistance value in the circuit. i L is the cross-sectional area of ​​the corresponding test tube. i The length of the corresponding test tube is given, ρ is the resistivity of the sol, and i = 1, 2, and 3 represent the first test tube, the second test tube, and the third test tube, respectively.

2. The graphene dispersibility testing method according to claim 1, characterized in that: The amounts of palygorskite, deionized water, and graphene added are in a mass ratio of 0.5~3:90~100:0.2~1.

3. The graphene dispersibility testing method according to claim 1, characterized in that: In step S2, the stirring method is ultrasonic stirring, wherein when adding graphene to the precursor solution, the graphene is added while stirring for 5-10 minutes. The homogenization is performed in a homogenizer for 15-20 minutes.

4. The graphene dispersibility testing method according to claim 1, characterized in that: In step S4, resistivity data models for precursor solutions at different concentrations, resistivity data models for sols, and dispersibility data models for precursor solutions at different concentrations are established respectively. The resistivity data model of the sol is corrected by the resistivity data model of the precursor solution at the same concentration to obtain graphene dispersion and resistivity data models at different concentrations.

5. The graphene dispersibility testing method according to claim 1, characterized in that: In S5: By coupling the obtained data models of graphene dispersions and resistivity at different concentrations with the data models of precursor solutions at different concentrations, a data model of dispersibility and resistivity is obtained. Based on the dispersibility and resistivity data model, the dispersibility data of graphene in sol is obtained by obtaining the resistivity of the corresponding graphene dispersion.

6. A graphene dispersibility testing system, characterized in that: The graphene dispersibility test method according to any one of claims 1-5 includes: The grinding module grinds palygorskite; The ultrasonic module stirs the graphene when the precursor solution formed after grinding is added. The homogenization module homogenizes the precursor solution of the mixed graphene to form a sol; The testing device measures the resistivity of test tubes of different specifications to obtain the resistivity of the sol. The processing module obtains graphene dispersion data through the resistivity of the sol.

7. The graphene dispersibility testing system according to claim 6, characterized in that: The testing device is provided in three sets. Each testing device includes a DC power supply. The two poles of the DC power supply are respectively connected to a test circuit. The test circuit is respectively provided with a test switch, an ammeter, a voltmeter, and a variable resistor. Electrodes are respectively provided between the ends of the test circuit away from the DC power supply. A first test tube, a second test tube, and a third test tube are respectively provided between the two electrodes of the testing device. The two electrodes extend into the two ends of the first test tube, the second test tube, and the third test tube, respectively.

8. The graphene dispersibility testing system according to claim 7, characterized in that: The first test tube, the second test tube, and the third test tube are all cylindrical in shape, and the specifications of the first test tube, the second test tube, and the third test tube are different.

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