A nanocomposite material and its preparation method, use method and device

Abstract

The present application discloses a nanocomposite material and a preparation method, a use method and a device thereof. The nanocomposite material is characterized in that it comprises a first nanoparticle and a second nanoparticle combined; the first nanoparticle is a transition metal nanoparticle, and the second nanoparticle is one of the following materials or a combination thereof: lithium nitride nanoparticles, lithium oxide nanoparticles, lithium phosphide nanoparticles, lithium selenide nanoparticles and lithium sulfide nanoparticles. The nanocomposite material can be magnetically controlled at low voltage to achieve high-speed and high-density electronic spin information storage.

Description

[0001] This application claims the priority of the Chinese patent application filed with the China Patent Office on July 9, 2020, with application number 202010656576.9, and invention name “A nanocomposite material, preparation method, use method and device thereof”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of material technology, and in particular to a nanocomposite material and a preparation method, a use method and a device thereof. Background Art

[0003] Electric field control of magnetism refers to the use of electric field to control the magnetic properties of materials, using electric field instead of magnetic field or current to control magnetism to realize the reading and writing of information storage, which can effectively meet the increasingly high requirements of new information storage devices in terms of high density, high speed, low power consumption, non-volatility, etc. In the prior art, there are mainly the following methods for using electric field to control magnetism: in a ferromagnetic film / insulating layer structure similar to a field effect tube, a strong electric field is used to control the enrichment or dissipation of magnetic-related carriers in the magnetic film to achieve the control of magnetism by electric field; in a composite structure composed of piezoelectric effect materials and magnetostrictive effect materials, the control of magnetism by electric field is achieved through the stress interaction at the interface between the two; in a single-phase multiferroic material / ferromagnetic film structure, the magnetoelectric coupling of ferroelectricity and antiferromagnetism in the multiferroic material and the exchange bias effect between the antiferromagnetism in the multiferroic material and the ferromagnetic film at the interface are used to achieve the purpose of controlling magnetism by electric field.

[0004] However, the above electric field control of magnetism usually needs to be carried out at lower temperatures or higher voltages, and the corresponding device preparation costs are high, which seriously limits the application of electric field control of magnetism in actual production and life. Summary of the invention

[0005] The embodiments of the present application provide a nanocomposite material and a preparation method, a use method and a device thereof, so as to solve the problem in the prior art that electric field regulation of magnetism usually needs to be carried out at a lower temperature or a higher voltage, and the corresponding device preparation cost is relatively high.

[0006] In a first aspect, an embodiment of the present application provides a nanocomposite material, comprising a first nanoparticle and a second nanoparticle combined;

[0007] The first nanoparticles are transition metal nanoparticles, and the second nanoparticles are one or a combination of the following materials:

[0008] Lithium nitride nanoparticles, lithium oxide nanoparticles, lithium phosphide nanoparticles, lithium selenide nanoparticles and lithium sulfide nanoparticles.

[0009] Preferably, the transition metal in the transition metal nanoparticles is one or a combination of the following elements:

[0010] Iron, cobalt, nickel and gadolinium.

[0011] In a second aspect, the present invention provides a method for preparing a nanocomposite material, the method comprising:

[0012] preparing a transition metal compound, wherein the transition metal compound is one of the following materials or a combination thereof: a transition metal oxide, a transition metal nitride, a transition metal phosphide, a transition metal selenide and a transition metal sulfide;

[0013] The transition metal compound is reduced by lithium ion discharge to obtain the nanocomposite material described in any one of the first aspects.

[0014] Preferably, the reduction of the transition metal compound by lithium ion discharge, the nanocomposite material according to any one of the first aspects, is specifically:

[0015] Using the transition metal compound as the first electrode of a lithium ion battery and using metallic lithium or a lithium source compound as the second electrode of the lithium ion battery;

[0016] The lithium ion battery is discharged, and the transition metal compound is reduced by the lithium ions to form the nanocomposite material described in the first aspect.

[0017] In a third aspect, the present application provides a method for preparing a nanocomposite material, the method comprising:

[0018] A first thin film material and a second thin film material are alternately grown by magnetron sputtering to obtain the nanocomposite material according to any one of the first aspects; wherein the first thin film material comprises the first nanoparticles according to any one of the first aspects, and the second thin film material comprises the second nanoparticles according to any one of the first aspects;

[0019] and / or,

[0020] The first material and the second material are ball-milled using a ball mill to obtain the nanocomposite material described in any one of the first aspects; wherein the first material is a material corresponding to the first nanoparticles described in any one of the first aspects, and the second material is a material corresponding to the second nanoparticles described in any one of the first aspects.

[0021] In a fourth aspect, the present application provides a method for using the nanocomposite material according to any one of the first aspects, the method comprising:

[0022] The nanocomposite material is used for magnetic regulation.

[0023] In a fifth aspect, an embodiment of the present application provides a spin capacitor, comprising a first electrode and a second electrode, wherein the first electrode is the nanocomposite material described in any one of the first aspects, and the second electrode is metallic lithium or a lithium source compound.

[0024] In a sixth aspect, an embodiment of the present application provides a method for using the spin capacitor according to the fifth aspect, the method comprising:

[0025] The spin capacitor is used to adjust and / or store spin information.

[0026] Preferably, the spin information storage using the spin capacitor is specifically:

[0027] The spin information storage is realized by controlling the applied voltage of the spin capacitor within a range less than the oxidation voltage of the transition metal.

[0028] In a seventh aspect, an embodiment of the present application provides a memory device, comprising the nanocomposite material described in any one of the first aspects, wherein the nanocomposite material is used to achieve information adjustment and / or storage through magnetic regulation.

[0029] In an eighth aspect, an embodiment of the present application provides a sensor, using the nanocomposite material described in any one of the first aspects, wherein the nanocomposite material is used to achieve sensing through magnetic regulation.

[0030] The magnetic control scheme provided in the embodiments of the present application has at least the following advantages:

[0031] 1. Magnetic regulation can be performed at low voltage to achieve high-speed and high-density electron spin information storage;

[0032] 2. Nanocomposites are prepared by chemical methods and have a large specific surface area;

[0033] 3. The preparation method has simple steps, low cost, low energy consumption, high efficiency and is easy to implement. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0035] Figure 1 A high-resolution transmission microscope image of the Fe / Li2O nanocomposite material provided in the embodiments of the present application;

[0036] Figure 2A schematic diagram of a method for preparing a nanocomposite material provided in an embodiment of the present application;

[0037] Figure 3 A schematic diagram of a lithium-ion battery provided in an embodiment of the present application;

[0038] Figure 4 A schematic diagram of a magnetization curve of a spin capacitor under different voltages provided in an embodiment of the present application;

[0039] Figure 5 A schematic diagram of the reversible cyclic change of saturation magnetization intensity with voltage provided in an embodiment of the present application. DETAILED DESCRIPTION

[0040] In order to enable those skilled in the art to better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work should fall within the scope of protection of the present application.

[0041] In view of the problems existing in the prior art, the embodiment of the present application provides a nanocomposite material that can be magnetically regulated in a relatively mild environment, wherein the nanocomposite material includes a first nanoparticle and a second nanoparticle combined;

[0042] The first nanoparticles are transition metal nanoparticles, and the second nanoparticles are one of the following materials or a combination thereof: lithium nitride nanoparticles, lithium oxide nanoparticles, lithium phosphide nanoparticles, lithium selenide nanoparticles, and lithium sulfide nanoparticles. For example, the second nanoparticles are lithium oxide nanoparticles, or a combination of lithium nitride nanoparticles and lithium oxide nanoparticles. In order to save space, an exhaustive description is not given here.

[0043] In an optional embodiment, the transition metal in the transition metal nanoparticles is one of the following elements or a combination thereof: iron, cobalt, nickel and gadolinium. For example, the transition metal may be iron, or a combination of iron and cobalt, which will not be exhaustively described here to save space.

[0044] In the embodiments of the present application, the combined first nanoparticle and the second nanoparticle can be understood as having a contact surface between the first nanoparticle and the second nanoparticle. For example, the first nanoparticle and the second nanoparticle can be mixed to form a contact surface between the first nanoparticle and the second nanoparticle, or the first nanoparticle film and the second nanoparticle film can be formed to form a contact surface between the contact surfaces of the first nanoparticle film and the second nanoparticle film.

[0045] It should be pointed out that the above-mentioned transition metals are only several possible implementation methods listed in this application and should not be used as a limitation on the protection scope of this application.

[0046] In an optional embodiment, the nanocomposite material may be a Fe / Li2O nanocomposite material, Figure 1 This is a high-resolution transmission microscope image of the Fe / Li2O nanocomposite material provided in the examples of the present application.

[0047] In addition to Fe / Li2O nanocomposite materials, the nanocomposite materials provided in the embodiments of the present application can also be Co / Li2O nanocomposite materials, Ni / Li2O nanocomposite materials, Ga / Li2O nanocomposite materials, Fe / Li3N nanocomposite materials, Co / Li3N nanocomposite materials, Ni / Li3N nanocomposite materials, Ga / Li3P nanocomposite materials, Fe / Li3P nanocomposite materials, Co / Li3P nanocomposite materials, Ni / Li3P nanocomposite materials, Ga / Li3P nanocomposite materials, Fe / Li2Se nanocomposite materials, Co / Li2Se nanocomposite materials, Ni / Li2Se nanocomposite materials, Ga / Li2Se nanocomposite materials, Fe / Li2S nanocomposite materials, Co / Li2S nanocomposite materials, Ni / Li2S nanocomposite materials, and Ga / Li2S nanocomposite materials.

[0048] Figure 2 A schematic diagram of a method for preparing a nanocomposite material provided in an embodiment of the present application, which is used to prepare Figure 1 The nanocomposite material. Figure 2 As shown, the method mainly includes the following steps.

[0049] Step S201: preparing a transition metal compound.

[0050] Corresponding to the second nanoparticles in the nanocomposite material of the above embodiment, the transition metal compound prepared in the embodiment of the present application can be one of the following materials or a combination thereof: transition metal oxides, transition metal nitrides, transition metal phosphides, transition metal selenides and transition metal sulfides.

[0051] For example, when the transition metal compound is a transition metal oxide, the second nanoparticles in the final nanocomposite material are lithium oxide nanoparticles; when the transition metal compound is a transition metal nitride, the second nanoparticles in the final nanocomposite material are lithium nitride nanoparticles. Of course, the transition metal compound can also be a combination of a transition metal oxide and a transition metal nitride.

[0052] In addition, the transition metal in the transition metal nanoparticles is one of the following elements or a combination thereof: iron, cobalt, nickel and gadolinium.

[0053] Taking Fe3O4 as an example, the preparation method of transition metal compounds is described in detail.

[0054] Mix 40 mL of an aqueous solution of 2 mmol of ferric chloride hexahydrate (FeCl3·6H2O), 8 mmol of sodium citrate (Na3C6H5O7·2H2O), 6 mmol of urea (CH4N2O) and a certain amount of sodium polyacrylate. After 2 hours of vigorous stirring, transfer the mixture to a 60 mL sealed Teflon-lined autoclave. Heat the autoclave in an oven at 200°C for 6 hours and then cool to room temperature. Collect the precipitate by centrifugation (8,000 rpm, 5 minutes), wash repeatedly with distilled water and ethanol, and dry to obtain Fe3O4 nanomaterials.

[0055] Step S202: reducing the transition metal compound by lithium ion discharge to obtain a nanocomposite material.

[0056] Taking Fe3O4 as an example, the Fe3O4 prepared in the above steps is reduced by lithium ion discharge to obtain a Fe / Li2O nanocomposite material.

[0057] In a specific implementation, Fe3O4 nanomaterials are assembled into lithium-ion batteries for discharge reduction to obtain Fe / Li2O nanocomposite materials.

[0058] Figure 3 A schematic diagram of a lithium-ion battery provided in an embodiment of the present application, such as Figure 3 As shown, the lithium-ion battery comprises a first electrode 301, a second electrode 302 and a separator 303, wherein the first electrode 301 is a Fe3O4 nanomaterial, and the second electrode 302 is a metallic lithium or a lithium source compound. When the lithium-ion battery is discharged, the Fe3O4 nanomaterial is reduced by lithium ions to a Fe / Li2O nanocomposite material, such as Figure 3The discharge degree of the lithium ion battery affects the reduction degree of the Fe3O4 nanomaterial. For example, the lithium ion battery can be discharged to 0.1V, 0.01V, 0V, etc., which is not specifically limited in the present embodiment. Of course, it is preferred to discharge the lithium ion battery to 0V so that the electrode material can fully react.

[0059] In addition to preparing Fe / Li2O nanocomposites, the above method can also be used to prepare Co / Li2O nanocomposites, Ni / Li2O nanocomposites, Ga / Li2O nanocomposites, Fe / Li3N nanocomposites, Co / Li3N nanocomposites, Ni / Li3N nanocomposites, Ga / Li3P nanocomposites, Fe / Li3P nanocomposites, Co / Li3P nanocomposites, Ni / Li3P nanocomposites, Ga / Li3P nanocomposites, Fe / Li2Se nanocomposites, Co / Li2Se nanocomposites, Ni / Li2Se nanocomposites, Ga / Li2Se nanocomposites, Fe / Li2S nanocomposites, Co / Li2S nanocomposites, Ni / Li2S nanocomposites, and Ga / Li2S nanocomposites.

[0060] Based on the above embodiments, Figure 3 After the lithium-ion battery is discharged, a spin capacitor is obtained. Specifically, the spin capacitor includes a first electrode and a second electrode, the first electrode is the nanocomposite material involved in the above embodiment, and the second electrode is metallic lithium or a lithium source compound. The lithium source compound is lithium cobalt oxide, lithium iron phosphate, lithium nickel oxide, etc.

[0061] The spin capacitor was placed in a constant magnetic field of 50000 Oe, and cyclic charge and discharge was performed within a voltage range of 0-1 V, while the variation of saturation magnetization intensity with voltage was tested. Figure 4 A schematic diagram of a magnetization curve of a spin capacitor under different voltages provided in an embodiment of the present application is shown in FIG. Figure 4 As shown, in the spin capacitor provided in the embodiment of the present application, a voltage of 1 volt causes a saturation magnetization intensity change of up to 16 emu / g, and the saturation magnetization intensity changes reversibly with the voltage as shown in FIG. Figure 5 shown.

[0062] The principle is that within this voltage range, magnetic regulation is performed based on the spin capacitance effect of space charge storage. Specifically, a space charge region is formed on the surface of the transition metal, that is, electrons can continue to be stored in the 3d split orbit at the Fermi surface, thereby achieving the purpose of magnetic regulation. This regulation method has the advantages of fast response speed, low energy consumption, non-volatility, stable reversibility and long life. Therefore, the nanocomposite material provided in the embodiment of the present application can be magnetically regulated at low voltage.

[0063] In a possible application scenario, spin information can be stored by a spin capacitor. Specifically, spin information adjustment and / or storage is achieved by controlling the applied voltage of the spin capacitor within a range less than the oxidation voltage of transition metals.

[0064] It is understandable that, within a voltage range less than the transition metal oxidation voltage, different voltages are applied to the spin capacitor, and the spin information corresponding to the spin capacitor is different. Therefore, a voltage threshold can be set, and when the voltage applied by the spin capacitor is less than the voltage threshold, the corresponding spin information is the first spin information, and when the voltage applied by the spin capacitor is greater than the voltage threshold, the corresponding spin information is the second spin information. It is understandable that when the voltage applied by the spin capacitor is stable within a certain voltage value or voltage threshold range, the spin information corresponding to the spin capacitor remains unchanged, so spin information storage can be achieved.

[0065] In addition, when the spin information of the spin capacitor needs to be adjusted, the spin capacitor can be charged and / or discharged within a voltage range less than the transition metal oxidation voltage to adjust the voltage applied to the spin capacitor, thereby adjusting the spin information.

[0066] In the embodiment of the present application, the spin capacitor can perform high-speed and high-density electron spin information storage at a low voltage.

[0067] In some possible implementations, the spin information corresponds to magnetism, and adjustment of the spin information is adjustment of the magnetism.

[0068] In a possible application scenario, the nanocomposite material provided in the embodiment of the present application can be applied to a memory, and information adjustment and / or storage can be achieved by regulating the magnetism of the nanocomposite material. For example, a magnetic threshold is set. When the magnetism of the nanocomposite material is less than the magnetic threshold, the information represented is defined as "0"; when the magnetism of the nanocomposite material is greater than the magnetic threshold, the information represented is defined as "1". By adjusting the voltage applied to the nanocomposite material, the magnetism of the nanocomposite material can be adjusted, that is, the information stored in the nanocomposite material can be adjusted. Therefore, information adjustment and / or storage can be achieved by regulating the magnetism of the nanocomposite material. In a possible application scenario, the nanocomposite material provided in the embodiment of the present application is applied to a sensor, and induction is achieved by the magnetic change of the nanocomposite material.

[0069] Since the nanocomposite material provided in the embodiments of the present application can achieve a large magnetic change at a low voltage, its application in sensors has a good effect.

[0070] Apart from Figure 2 In addition to the method for preparing the nanocomposite material shown, in some possible implementations, the nanocomposite material may also be prepared by a magnetron sputtering method or a ball milling method.

[0071] Specifically, a first thin film material and a second thin film material are alternately grown by magnetron sputtering to obtain Figure 1 The nanocomposite material; wherein the first film material comprises Figure 1 The first nanoparticles in the embodiment, the second thin film material comprises Figure 1 The second nanoparticle of the embodiment.

[0072] The first material and the second material are ball milled by a ball mill to obtain Figure 1 The nanocomposite material; wherein the first material is Figure 1 The first nanoparticles in the embodiment correspond to the material, and the second material is Figure 1 The material corresponding to the second nanoparticles in the embodiment.

[0073] It should be noted that, in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0074] The above description is only a specific embodiment of the present invention, so that those skilled in the art can understand or implement the present invention. Various modifications to these embodiments will be 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 present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but should conform to the widest scope consistent with the principles and novel features disclosed herein.

[0075] In this specification, the same or similar parts between the various embodiments can be referred to each other. In particular, for the terminal embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the description in the method embodiment.

[0076] The above-described embodiments of the present application do not constitute a limitation on the protection scope of the present application.

Claims

1. A nanocomposite material, characterized in that: comprising a first nanoparticle and a second nanoparticle combined; The first nanoparticles are transition metal nanoparticles, and the second nanoparticles are one or a combination of the following materials: Lithium nitride nanoparticles, lithium oxide nanoparticles, lithium phosphide nanoparticles, lithium selenide nanoparticles, and lithium sulfide nanoparticles; The nanocomposite material is used for magnetic regulation.

2. The nanocomposite material according to claim 1, characterized in that The transition metal in the transition metal nanoparticles is one or a combination of the following elements: Iron, cobalt, nickel and gadolinium.

3. A method for preparing a nanocomposite material, characterized in that: The method comprises: preparing a transition metal compound, wherein the transition metal compound is one of the following materials or a combination thereof: a transition metal oxide, a transition metal nitride, a transition metal phosphide, a transition metal selenide and a transition metal sulfide; The transition metal compound is reduced by lithium ion discharge to obtain the nanocomposite material according to claim 1 or 2.

4. A spin capacitor, characterized in that: The spin capacitor comprises a first electrode and a second electrode, the first electrode is the nanocomposite material according to claim 1, and the second electrode is metallic lithium or a lithium source compound.

5. A method for using the spin capacitor according to claim 4, characterized in that: The method comprises: The spin capacitor is used to adjust and / or store spin information by controlling the applied voltage of the spin capacitor within a range less than the oxidation voltage of transition metals.

6. A memory, characterized in that: The nanocomposite material comprises the nanocomposite material as claimed in claim 1, wherein the nanocomposite material is used to achieve information adjustment and / or storage through magnetic regulation.

7. A sensor, characterized in that: The nanocomposite material comprises the nanocomposite material as claimed in claim 1, wherein the nanocomposite material is used to achieve induction through magnetic regulation.

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