A lapis lazuli blue film composite material and preparation method thereof
Through the electrically induced deposition process and the self-assembly and stacking method that forms orientation at the substrate interface, the problem of difficulty in preparing large-area homogeneous organic nanofiber films in the prior art is solved, and the high-performance preparation of celestial blue film composites is achieved, and the performance of electrical storage information devices is improved.
Patent Information
- Application Number
- CN202111355127.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2021-11-16
- Publication Date
- 2025-05-13
- Estimated Expiration
- 2041-11-16
AI Technical Summary
The prior art is difficult to prepare large-area and homogeneous organic nanofiber films, resulting in poor performance in electrical storage information devices.
An electrically induced deposition process is used to synthesize nanofiber films with controllable sizes in organic solvents, and an orientation-oriented self-assembly and stacking method is formed at the substrate interface through external electric field forces.
The preparation of azurestone blue film composite material is realized, which enhances the stacking tightness between molecules and the ductility of the film, ensures the transfer of charge in the molecule and the resistance change based on the electrical signal response, and improves the performance of information storage and erasing.
Smart Images
Figure CN114122258B_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the field of composite materials, and in particular relates to a lapis lazuli blue film composite material and a preparation method thereof. Background Art
[0002] The 21st century is an era of science and technology. With the rapid development of society, people are increasingly yearning for the convenient life brought by intelligence. However, the development of intelligence comes from the strong support of hardware equipment on the one hand, and depends on the rapid development of "big data" and its storage technology on the other. The amount of data processed every day in the current society is increasing exponentially, and the society's requirements for memory are getting higher and higher. Therefore, the safe, efficient and large-capacity storage of data has become the vanguard of the "big data" era. Organic electrical storage information materials and nanodevices with binary or even multi-ary information storage functions have become a hot topic for scientists. Organic nanofibers have been widely studied in the field of constructing organic nanodevices, and their advantages are mainly reflected in the following aspects: 1. Compared with the main structure, nanofibers have better mechanical properties and have great development potential in the field of flexible organic electronic devices; 2. Nanofibers can form stable electron transmission channels along the long axis and diameter direction, so they have excellent electrical properties.
[0003] So far, researchers have explored a variety of physical and chemical strategies to synthesize nanofibers of conjugated materials, including spontaneous thermodynamic and kinetic methods (e.g., thermal evaporation, solvothermal, sol-gel, chemical vapor deposition, etc.) and external force-assisted methods (e.g., template-assisted, magnetic field-assisted). However, all of the above methods have certain limitations. For example, thermal evaporation has high energy consumption and low controllability; the external force-assisted method has a cumbersome process flow; traditional film-forming methods (e.g., spin coating and vacuum evaporation) produce non-equilibrium morphology due to rapid quenching due to solvent volatilization or thermal effects of the film, which is not conducive to obtaining uniform nanofiber self-assembled fragments on the substrate. In addition, all of the above problems pose great challenges to the preparation of large-area and homogeneous organic nanofiber films. Therefore, using the electrically induced deposition process to synthesize size-controllable nanofiber films in organic solvents, and using the external electric field force to form an oriented self-assembled stacking mode at the substrate interface, is of great significance for improving the performance of electrical storage information devices. Summary of the invention
[0004] The purpose of the present invention is to provide a lapis lazuli blue thin film composite material, the preparation method of which not only effectively enhances the compactness of the stacking between organic functional material molecules and the ductility of the film, but also ensures the transfer process of the charge within the molecule, induces the resistance state change based on the response of the electric signal, and realizes the storage and erasure of information. At the same time, an application of the lapis lazuli blue thin film composite material in the field of information storage is provided.
[0005] The present invention provides a method for preparing a lapis lazuli blue thin film composite material, comprising the following steps:
[0006] (1) dissolving lapis lazuli blue in dimethyl sulfoxide and adding acetonitrile to obtain a precursor solution.
[0007] (2) depositing the precursor solution onto a conductive substrate to form a fiber film layer;
[0008] (3) A fluoride layer and a top electrode layer are sequentially evaporated on the surface of the fiber film layer to obtain the lapis lazuli blue film composite material.
[0009] Preferably, in step (1), the dimethyl sulfoxide and acetonitrile are mixed at a temperature of 20-30° C. for 8-16 hours.
[0010] Preferably, in step (1), the volume ratio of dimethyl sulfoxide to acetonitrile is 1:8-10.
[0011] Preferably, in step (1), the concentration of lapis lazuli blue in the precursor solution is 0.1-0.3 mg / mL.
[0012] Preferably, the conductive substrate is an indium tin oxide (ITO) layer substrate or a zinc oxide (FTO) layer substrate; the fluoride layer is a lithium fluoride layer or a magnesium fluoride layer; and the top electrode layer is a metal Au layer, an Ag layer or an Al layer.
[0013] Preferably, the specific operation of step (2) is as follows: placing the precursor solution in an electrolytic cell, with a conductive substrate as the cathode, and the anode is preferably a conductive substrate.
[0014] A closed electric field induced deposition workstation is built, and the electrodes of the workstation are placed at the left and right ends of the electrolytic cell. A voltage is applied to deposit a fiber film layer on the cathode surface.
[0015] Furthermore, the deposition conditions are 5-15V DC voltage, and the distance between the cathode and the anode is 8-12mm. The electrolytic cell capacity is 2-4cm 3 , time 4-6 minutes.
[0016] Furthermore, in step (3), the evaporation rate of the fluoride layer is The thickness is 8-12nm.
[0017] Furthermore, in step (3), the top electrode layer is vacuum-deposited onto the lithium fluoride layer through a mask plate with a circular hole array, and the evaporation rate is The thickness is 80-120nm and the vacuum degree is 1×10 -6 -1×10 -4 Torr.
[0018] The invention also provides a lapis lazuli blue film composite material prepared by the preparation method.
[0019] The invention also provides an application of the lapis lazuli blue thin film composite material as an electric storage device.
[0020] The technical solution of the present invention has the following advantages over the prior art:
[0021] 1. In the mixed solvent of the present invention, dimethyl sulfoxide is used as a good solvent for celestine blue, and acetonitrile is used as a poor solvent for celestine blue. The celestine blue molecule is composed of a cationic conjugated skeleton, a chloride anion, a hydroxyl group and an amide group, which is beneficial to enhancing the non-covalent bond between adjacent molecules, including hydrogen bonds, Coulomb forces and van der Waals forces; secondly, the conjugated skeleton close to the plane can enhance the π-π interaction inside the material and induce the orientation of molecular stacking; the charge transfer effect within the molecule induces a storage effect based on an electrical signal response.
[0022] 2. The film prepared by electrical induction of the present invention has excellent uniformity, continuity, large-area stability and flexibility. The film has dense molecular accumulation inside, which effectively avoids the problems caused by the formation of cracks in the crystal lines, excessive gaps and irregular crystallization. The uniformity-controllable electrical storage array is prepared, which is conducive to improving the electrical stability and performance reproducibility of the storage active layer, and provides an important guarantee for the production and application of large-area organic thin films and flexible electronic devices. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 Schematic diagram of the electric field induced deposition workstation for the preparation of lapis lazuli blue nanofiber film;
[0024] Figure 2 This is an atomic force microscope (AFM) image of the lapis lazuli blue nanofiber film;
[0025] Figure 3 A cross-sectional view of an atomic force microscope image of a lapis lazuli blue nanofiber film;
[0026] Figure 4 This is the ultraviolet absorption spectrum of the lapis lazuli blue nanofiber film;
[0027] Figure 5 A schematic diagram of the structure of an electrical storage device of lapis lazuli blue nanofiber film;
[0028] Figure 6 The electrical performance diagram of the electrical storage device with the structure of "bottom electrode / lapis lazuli blue / top electrode" is shown;
[0029] Figure 7 This is a distribution diagram of the electrical performance characteristic parameters of the electrical storage device with a "bottom electrode / lapis lazuli blue / top electrode" structure.
[0030] Explanation of the reference numerals: 1 - top electrode layer, 2 - fluoride layer, 3 - lapis lazuli blue film, 4 - conductive substrate, 5 - glass. DETAILED DESCRIPTION
[0031] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.
[0032] Example 1
[0033] 2 mg of celestine blue molecules were dissolved in a mixture of 1 mL of dimethyl sulfoxide and 9 mL of acetonitrile, and stirred for 12 h to fully dissolve, and finally a mixed solution was obtained as a precursor for the preparation of nanofiber films;
[0034] Place the prepared precursor solution in a pre-designed 3 cm 3 In the electrolytic cell. A closed electric field induced deposition workstation was built, and the electrodes of the workstation were placed at the left and right ends of the electrolytic cell with an electrode spacing of 1 mm. Then a voltage of 10 V was applied, and the deposition was continued for 5 minutes. The lapis lazuli blue material self-assembled in the electrolytic cell and slowly deposited onto the conductive indium tin oxide layer substrate 4 to obtain a uniform and dense organic nanofiber film layer. Subsequently, the film after deposition was taken out of the electrolytic cell with a pulling instrument, and placed flat in a 100°C vacuum oven for drying to obtain a lapis lazuli blue film 3.
[0035] In 10 -6 Under the condition of a vacuum degree of Torr, a lithium fluoride layer 2 is evaporated on the surface of the nanofiber film layer at a evaporation rate of The thickness is 10nm. Then, the metal Al electrode is vacuum-deposited onto the surface of the lithium fluoride layer through a mask plate with a uniform array of circular holes. The evaporation rate is The thickness is 100 nm, and the top electrode layer 1 is obtained, which is placed on the glass 5 to obtain the lapis lazuli blue thin film composite material.
[0036] Example 2
[0037] 4 mg of celestine blue molecules were dissolved in a mixture of 1.8 mL of dimethyl sulfoxide and 18.2 mL of acetonitrile, stirred for 8 h to fully dissolve, and finally a mixed solution was obtained as a precursor for the preparation of nanofiber films;
[0038] Place the prepared precursor solution in a pre-designed 2 cm 3In the electrolytic cell. A closed electric field induced deposition workstation was built, and the electrodes of the workstation were placed at the left and right ends of the electrolytic cell with an electrode spacing of 8 mm. Then a voltage of 5 V was applied and the deposition was continued for 6 minutes. The celestite blue material self-assembled in the electrolytic cell and slowly deposited on the conductive indium tin oxide layer substrate to obtain a uniform and dense organic nanofiber film layer. The film after deposition was then taken out of the electrolytic cell with a pulling instrument and placed flat in a 100°C vacuum oven for drying to obtain a celestite blue film.
[0039] In 10 -4 Under the condition of a vacuum degree of Torr, a layer of lithium fluoride is evaporated on the surface of the nanofiber film layer at a rate of The thickness is 8nm. Then, the metal Al electrode is vacuum-deposited onto the surface of the lithium fluoride layer through a mask plate with a uniform array of circular holes at a deposition rate of The thickness is 80 nm, and a lapis lazuli blue thin film composite material is obtained.
[0040] Example 3
[0041] 6 mg of celestine blue molecules were dissolved in a mixture of 3.3 mL of dimethyl sulfoxide and 26.7 mL of acetonitrile, and stirred for 16 h to fully dissolve, and finally a mixed solution was obtained as a precursor for the preparation of nanofiber films;
[0042] Place the prepared precursor solution in a pre-designed 4 cm 3 In the electrolytic cell. A closed electric field induced deposition workstation was built, and the electrodes of the workstation were placed at the left and right ends of the electrolytic cell with an electrode spacing of 12 mm. Then a voltage of 15 V was applied and the deposition was continued for 4 minutes. The lapis lazuli blue material self-assembled in the electrolytic cell and slowly deposited on the conductive indium tin oxide layer substrate to obtain a uniform and dense organic nanofiber film layer. The film after deposition was then taken out of the electrolytic cell with a pulling instrument and placed flat in a 100°C vacuum oven for drying to obtain a lapis lazuli blue film.
[0043] In 10 -6 Under the condition of a vacuum degree of Torr, a layer of lithium fluoride is evaporated on the surface of the nanofiber film layer at a rate of The thickness is 12nm. Then, the metal Al electrode is vacuum-deposited onto the surface of the lithium fluoride layer through a mask plate with a uniform array of circular holes at a deposition rate of The thickness is 120 nm, and a lapis lazuli blue thin film composite material is obtained.
[0044] Example 4
[0045] 6 mg of celestine blue molecules were dissolved in a mixture of 3.3 mL of dimethyl sulfoxide and 26.7 mL of acetonitrile, and stirred for 16 h to fully dissolve, and finally a mixed solution was obtained as a precursor for the preparation of nanofiber films;
[0046] Place the prepared precursor solution in a pre-designed 4 cm 3 In the electrolytic cell. A closed electric field induced deposition workstation was built, and the electrodes of the workstation were placed at the left and right ends of the electrolytic cell with an electrode spacing of 12 mm. Then a voltage of 15 V was applied and the deposition was continued for 4 minutes. The lapis lazuli blue material self-assembled in the electrolytic cell and slowly deposited on the conductive zinc oxide layer substrate to obtain a uniform and dense organic nanofiber film layer. The film after deposition was then taken out of the electrolytic cell with a pulling instrument and placed flat in a 100°C vacuum oven for drying to obtain a lapis lazuli blue film.
[0047] In 10 -6 Under the condition of a vacuum degree of Torr, a layer of magnesium fluoride is evaporated on the surface of the nanofiber film layer at a evaporation rate of The thickness is 12nm. Then, the metal Ag electrode is vacuum-deposited onto the surface of the magnesium fluoride layer through a mask plate with a uniform array of circular holes. The evaporation rate is The thickness is 120 nm, and a lapis lazuli blue thin film composite material is obtained.
[0048] Effect evaluation 1
[0049] Under the induction of electric field, the lapis lazuli blue molecules will realize self-assembly arrangement and orderly deposit on the electrode interface, such as Figure 1 As shown. AFM image of lapis lazuli blue nanofiber film ( Figure 2 and Figure 3 ) It can be seen that the lapis lazuli blue nanofibers were successfully prepared, and the film showed good uniformity and continuity at the microscopic scale. From the cross-sectional view, the width of a single nanofiber was approximately 100 nm.
[0050] The ultraviolet absorption spectrum of the nanofiber film ( Figure 4 ), the broader peak shape and red shift indicate that lapis lazuli blue has stronger molecular forces and charge transfer effects in the fiber film state.
[0051] Effect evaluation 2
[0052] The performance test of the electrical storage material with the structure of "bottom electrode / fiber film / top electrode" is carried out. The specific steps are as follows:
[0053] The prepared electrical memory material was tested using the 4200-SCS semiconductor test system produced by Keithley, USA, at 25°C and 30% humidity. The current-voltage characteristic curve of the device was tested by applying a 0 to ±5V DC voltage scan, and 50 groups of device units were tested continuously. Finally, the distribution of characteristic parameters of device performance under multiple tests was statistically analyzed to further investigate the electrical stability and performance reproducibility of the electrical memory material based on the nanofiber film.
[0054] Characterization of the voltage-current performance of the memory device with the structure of "bottom electrode / nanofiber film / top electrode" ( Figure 6 ), it can be seen that the device exhibits similar binary resistance state changes based on the two storage states of "0" and "1" under positive electric field scanning. When a negative voltage is applied, the current level of the device changes from "1" to "0", showing volatile electrical storage characteristics.
[0055] According to the distribution characterization results of the electrical performance characteristic parameters of the electrical memory material with the "bottom electrode / lapis lazuli blue / top electrode" structure ( Figure 7 ), the threshold voltage distribution of the device based on the two states of on and off shows a good normal distribution. The on voltage distribution range is mainly concentrated in 1-2V, and the off voltage is mainly distributed in -3.5V to -4.5V.
[0056] In summary, the lapis lazuli blue thin film composite material prepared by the present invention has a reliable application prospect in the field of electrical storage devices.
[0057] Obviously, the above embodiments are merely examples for clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the protection scope of the invention.
Claims
1. A method for preparing a lapis lazuli blue film composite material, characterized in that: The following steps are involved: (1) dissolving lapis lazuli blue in dimethyl sulfoxide and adding acetonitrile to obtain a precursor solution; (2) depositing the precursor solution onto a conductive substrate to form a fiber film layer; the specific operation of step (2) is as follows: placing the precursor solution in an electrolytic cell, using the conductive substrate as a cathode, applying a voltage, and depositing the fiber film layer on the surface of the cathode; (3) A fluoride layer and a top electrode layer are sequentially evaporated on the surface of the fiber film layer to obtain the lapis lazuli blue film composite material.
2. The preparation method according to claim 1, characterized in that In the step (1), the volume ratio of dimethyl sulfoxide to acetonitrile is 1:8-10.
3. The preparation method according to claim 1, characterized in that: In the step (1), the concentration of lapis lazuli blue in the precursor solution is 0.1-0.3 mg / mL.
4. The preparation method according to claim 1, characterized in that: The conductive substrate is an indium tin oxide layer substrate or a zinc oxide layer substrate; The fluoride layer is a lithium fluoride layer or a magnesium fluoride layer; The top electrode layer is a metal Au layer, Ag layer or Al layer.
5. The preparation method according to claim 1, characterized in that: The deposition conditions were a DC voltage of 5-15 V and a distance between the cathode and the anode of 8-12 mm.
6. The preparation method according to claim 1, characterized in that: In the step (3), the evaporation rate of the fluoride layer is 0.04-0.06Å / s, and the thickness is 8-12nm.
7. The preparation method according to claim 1, characterized in that: In step (3), the top electrode layer is evaporated onto the lithium fluoride layer at a rate of 0.8-1.2 Å / s, a thickness of 80-120 nm, and a vacuum degree of 1×10 -6 -1×10 -4 Torr.
8. A lapis lazuli blue thin film composite material prepared by the preparation method according to any one of claims 1 to 7.
9. Use of the lapis lazuli blue thin film composite material as claimed in claim 8 as an electrical storage device.