Room-temperature ferromagnetic graphdiyne material and large-scale preparation method and application thereof

Abstract

The invention discloses a room-temperature ferromagnetic graphdiyne material and a large-scale preparation method and application thereof.The graphdiyne material with multiple functions, high crystallinity and room-temperature ferromagnetism can be obtained through ball milling, annealing, washing and secondary annealing, the graphdiyne material is of a multi-fold sheet layer stacked structure, and the apparent density is 35-45 kg / m < 3 >; the ferromagnetic graphdiyne material has the super-hydrophobic characteristic, and the hydrophobic angle reaches 155.5 degrees or above; the lowest reflection loss of the ferromagnetic graphdiyne material to electromagnetic waves at the frequency of 17.37 GHz reaches-61.44 dB; the effective absorption bandwidth is greater than 5.5 GHz, the Ku wave band (12-18 GHz) is almost or completely covered, and the matching thickness is less than 2.28 mm; the material prepared by the method can also be used in the fields of infrared stealth materials, gas sensitive sensor materials, secondary battery electrode materials, optical and electro-catalytic materials, adsorption materials, ultraviolet protection materials, optical materials, semiconductor materials and the like, is simple in preparation process, low in cost and suitable for batch production, and is an electronic functional material with a very good prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of functional materials and relates to a ferromagnetic graphyne material, and in particular to a room temperature ferromagnetic graphyne material and a large-scale preparation method and application thereof. Background Art

[0002] In 1968, the famous materials scientist Baughman confirmed the existence of ferromagnetic graphyne structure through theoretical calculations. In 2010, the team led by Academician Li Yuliang of my country prepared the graphene diyne film for the first time in the world and named it graphyne in Chinese. It is composed of a full carbon polymer with a two-dimensional planar network structure formed by conjugating benzene rings with 1,3-diyne bonds. It has abundant carbon chemical bonds, a large conjugated system, wide interplanar spacing, excellent chemical stability and semiconductor properties. Graphene has a special electronic structure and natural hole characteristics, which makes the charge distribution extremely unbalanced, and is considered to be the only candidate for excellent absorbing materials.

[0003] However, due to the complexity of the existing preparation method of gydne, the prepared gydne samples still have problems such as low purity, low yield, and high density, which makes the gydne material have been delayed in application. Therefore, it is very necessary and very important to prepare ferromagnetic gydne materials with high yield and high crystallinity. The present invention uses it as a microwave absorption material, and it can also be used as an infrared stealth material, a gas sensor material, a secondary battery electrode material, a light, an electrocatalytic material, an adsorption material, an ultraviolet protection material, an optical material, a semiconductor material and many other fields. Summary of the invention

[0004] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a room-temperature ferromagnetic graphyne material and a large-scale preparation method and application thereof, so as to realize the preparation of ferromagnetic graphyne material with high purity, high yield and high crystallinity through a low-cost and simple method. The product has excellent wave absorption, hydrophobicity, adsorption and electrical properties, and has good application prospects in multiple fields.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A large-scale preparation method of room temperature ferromagnetic graphyne material comprises the following steps:

[0007] Step 1, taking calcium carbide and hexabromobenzene in a molar ratio of (4-8): 1 and placing them in a ball mill for ball milling. After the completion, taking out the sample, filtering and drying, and annealing at 350-600° C. for 2-6 hours under argon protection to obtain a coarse sample, washing and drying the coarse sample to obtain a semi-finished ferromagnetic graphyne;

[0008] Step 2: The semi-finished ferromagnetic gydne obtained in step 1 is subjected to secondary annealing at 650-1000° C. for 2-6 hours under argon protection to obtain a finished room temperature ferromagnetic gydne material.

[0009] The present invention also has the following technical features:

[0010] Preferably, the grinding balls in the ball mill described in step 1 are made of zirconium oxide, agate or stainless steel, and anhydrous ethanol is used as the solvent;

[0011] The ratio of the total mass of the grinding balls to the calcium carbide and the hexabromobenzene is (9-15):1; the ball milling process is to perform ball milling at a speed of 500-550 revolutions per minute for 16-24 hours.

[0012] Preferably, the washing in step 1 is washing with 0.5-1 mol / L dilute nitric acid, deionized water and anhydrous ethanol in sequence for 2-3 times.

[0013] The present invention also protects a room temperature ferromagnetic graphyne material prepared by the method as described above, which has a multi-folded layer stacking structure and a bulk density of 35 to 45 kg / m 3 ; The minimum reflection loss of electromagnetic waves at a frequency of 17.37GHz reaches -61.44dB, the effective absorption bandwidth is greater than 5.5GHz, and the matching thickness is less than 2.28mm.

[0014] The present invention also protects an application of the room temperature ferromagnetic graphyne material as described above in a microwave absorber, wherein the room temperature ferromagnetic graphyne material and paraffin are mixed in a mass ratio of 1:9, homogenized and then pressed to obtain a room temperature ferromagnetic graphyne material microwave absorbing coating, wherein the coating has a thickness of 1.8 to 2.28 mm.

[0015] The present invention also protects the room temperature ferromagnetic graphyne material as described above for use as infrared stealth material, ultraviolet protection material, gas sensitive sensor material, photoelectrocatalytic material, adsorption material, superhydrophobic material, secondary battery electrode material, optical material, and as semiconductor material in the manufacture of electronic components, spin electronic devices, integrated circuit chips and circuit systems.

[0016] Compared with the prior art, the present invention has the following technical effects:

[0017] The present invention obtains a multifunctional, high-purity, high-yield, high-crystallinity room-temperature ferromagnetic graphyne material through simple ball milling, annealing, washing, and secondary annealing processes. The preparation process is simple, the cost is low, and it is suitable for mass production. The prepared room-temperature ferromagnetic graphyne material has a multi-folded layer stacking structure and a bulk density of 35-45 kg / m 3The hydrophobic angle reaches more than 155.5°, with super hydrophobic characteristics and excellent wave absorbing performance. It shows an absorption bandwidth of 6.2GHz under the condition of a low filling ratio of 10%, and the minimum reflection loss of electromagnetic waves at a frequency of 17.37GHz reaches -61.44dB; the effective absorption bandwidth is greater than 5.5GHz, almost or completely covering the Ku band (12-18GHz), and the matching thickness is less than 2.28mm;

[0018] The material prepared by the method of the present invention can also be used as infrared stealth material, gas sensor material, secondary battery electrode material, as well as light, electrocatalytic material, adsorption material, ultraviolet protection material, optical material, semiconductor material and other fields. It is a very promising electronic multifunctional material. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 X-ray diffraction (XRD) patterns of the products of Examples 1 to 3;

[0020] Figure 2 (a) to (c) are scanning electron microscope (SEM) photos of the products of Examples 1 to 3;

[0021] Figure 3 The Raman spectra of the products of Examples 1 to 3 are shown in FIG.

[0022] Figure 4 This is a Fourier Transform Infrared spectroscopy (FTIR) image of the product of Example 1;

[0023] FIG5(a) is a graph showing the wave absorption performance of Example 1 of the present invention; FIG5(b) is a graph showing the wave absorption performance of Example 2 of the present invention; and FIG5(c) is a graph showing the wave absorption performance of Example 3 of the present invention;

[0024] Figure 6 This is a hydrophobic performance diagram of Example 2 of the present invention;

[0025] Figure 7 This is the ultraviolet-visible spectra of Example 3 of the present invention.

[0026] Figure 8 This is the hysteresis loop diagram of Example 1 of the present invention. DETAILED DESCRIPTION

[0027] The specific contents of the present invention are further explained in detail below in conjunction with embodiments.

[0028] Embodiment 1:

[0029] This embodiment provides a large-scale preparation method of room temperature ferromagnetic graphyne material, comprising the following steps:

[0030] Weigh 2 g of ground calcium carbide powder (AR pure) and 3.85 g of hexabromobenzene powder (AR pure) into a ball mill, add anhydrous ethanol, add 60 g of zirconium oxide grinding balls, and ball mill at a rate of 500 rpm for 16 hours; after ball milling, the mixed solution is filtered, and the obtained product is dried and annealed at 400°C for 2 hours under argon protection; the obtained product is washed twice with 0.5 mol / L dilute nitric acid, deionized water and anhydrous ethanol in sequence, dried at 70°C, and then annealed at 800°C for 2 hours; finally, the product is characterized by XRD, SEM and RAMAN.

[0031] The material sample prepared in this embodiment was homogenized with paraffin wax at a mass ratio of 1:9, and the resulting mixture was pressed into a ring with an outer diameter of 3.00 mm and an inner diameter of 7.00 mm, respectively, and the electromagnetic performance was tested in the frequency range of 2 to 18 GHz using a vector network analyzer. As can be seen from Figure 5(a), the optimal reflection loss of electromagnetic waves at a frequency of 17.37 GHz reaches -61.44 dB; the optimal bandwidth is 6.2 GHz, and at 11.80 to 18.00 GHz, the absorption bandwidth can cover the Ku band (12 to 18 GHz), and the matching thickness is only 1.86 mm.

[0032] Embodiment 2:

[0033] This embodiment provides a large-scale preparation method of room temperature ferromagnetic graphyne material, comprising the following steps:

[0034] Weigh 3 g of ground calcium carbide powder (AR pure) and 6 g of hexabromobenzene powder (AR pure) into a ball mill, add anhydrous ethanol, add 120 g of grinding balls, and ball mill at a rate of 500 rpm for 20 hours; after the ball milling, the mixed solution is filtered, and the obtained product is dried and annealed at 450°C for 3 hours under argon protection; the obtained product is washed twice with 0.6 mol / L dilute nitric acid, deionized water and anhydrous ethanol in sequence, dried at 70°C, and then annealed at 650°C for 6 hours; finally, the product is characterized by XRD, SEM and RAMAN.

[0035] Embodiment 3:

[0036] This embodiment provides a large-scale preparation method of room temperature ferromagnetic graphyne material, comprising the following steps:

[0037] 5.59 g of ground calcium carbide powder (AR pure) and 6 g of hexabromobenzene powder (AR pure) were weighed and added into a ball mill, anhydrous ethanol was added, 180 g of grinding balls were added, and ball milling was performed at a rate of 500 rpm for 22 hours; after the ball milling, the mixed liquid was filtered, and the obtained product was dried and annealed at 550°C for 4 hours under argon protection; the obtained product was washed with 1 mol / L dilute nitric acid, deionized water and ethanol in turn, dried at 70°C, and then annealed at 800°C for 3 hours; finally, the product was characterized by XRD, SEM and RAMAN.

[0038] Embodiment 4:

[0039] This embodiment provides a large-scale preparation method of room temperature ferromagnetic graphyne material, comprising the following steps:

[0040] Weigh 3 g of ground calcium carbide powder (AR pure) and 6.256 g of hexabromobenzene powder (AR pure) into a ball mill, add 83.3 g of grinding balls, and ball mill at 520 rpm for 24 hours; after ball milling, the mixed solution is filtered, and the obtained product is dried and annealed at 350°C for 6 hours under argon protection; the obtained product is washed three times with 0.5 mol / L dilute nitric acid, deionized water and anhydrous ethanol in sequence, dried at 70°C, and then annealed at 950°C for 4 hours; finally, the product is characterized by XRD, SEM and RAMAN.

[0041] Embodiment 5:

[0042] This embodiment provides a large-scale preparation method of room temperature ferromagnetic graphyne material, comprising the following steps:

[0043] 4 g of ground calcium carbide powder (AR pure) and 7.435 g of hexabromobenzene powder (AR pure) were weighed and added into a ball mill, anhydrous ethanol was added, 147.5 g of grinding balls were added, and ball milling was performed at a rate of 550 rpm for 18 hours; after the ball milling, the mixed liquid was filtered, and the obtained product was dried and annealed at 600°C for 2 hours under argon protection; the obtained product was washed twice with 0.5 mol / L dilute nitric acid, deionized water and anhydrous ethanol in sequence, dried at 70°C, and then annealed at 1000°C for 3 hours; finally, the product was characterized by XRD, SEM and RAMAN.

[0044] Figure 1 The X-ray diffraction (XRD) patterns of the products of Examples 1 to 3 show that the products are γ-ferromagnetic graphyne. The patterns show that the characteristic peaks of the products are sharp and the half-width is small, which proves that the products have a high degree of crystallinity.

[0045] Figure 2(a) to (c) are scanning electron microscope (SEM) photos of the products of Examples 1 to 3. It can be seen from the figures that the prepared samples present a multi-fold lamellar stacking structure.

[0046] Figure 3 The Raman spectra of the products of Examples 1 to 3 of the present invention are shown in the figure. It can be seen from the figure that the prepared products contain sp 2 The presence of two bonds, sp-C and sp-C, proves that the product is ferromagnetic graphyne; the low ID / IG value proves that its degree of disorder is low and it has a high crystallinity.

[0047] Figure 4 This is a Fourier transform infrared spectrum (FTIR) image of the product of Example 1 of the present invention. In the figure, 667 cm -1 and 2341cm -1 The peak at 827 cm corresponds to the vibration peak of the ethynyl group (sp-C), -1 and 1624cm -1 The peak at corresponds to the benzene ring (sp 2 -C) vibration peak.

[0048] Figure 5(a) is a wave absorption performance diagram of Example 1 of the present invention. It can be seen from the figure that the minimum reflection loss of electromagnetic waves at a frequency of 17.37 GHz reaches -61.44 dB; the effective absorption bandwidth is 6.2 GHz (11.80-18.00 GHz), covering the Ku band (12-18 GHz), and the matching thickness is only 1.86 mm; Figure 5(b) is a wave absorption performance diagram of Example 2 of the present invention; Figure 5(c) is a wave absorption performance diagram of Example 3 of the present invention.

[0049] Figure 6 This is a hydrophobic performance diagram of Example 2 of the present invention. As can be seen from the figure, the product has super hydrophobic properties, and the hydrophobic angle reaches 155.5°.

[0050] Figure 7 3 is an ultraviolet-visible spectra diagram of Example 3 of the present invention. It can be seen from the diagram that room temperature ferromagnetic graphyne has ultraviolet nonlinear absorption characteristics.

[0051] Figure 8 This is the hysteresis loop diagram of Example 1 of the present invention. It can be seen from the figure that the prepared product has ferromagnetism.

[0052] The above-described embodiments are only preferred specific embodiments of the present invention and are not limited to the present invention. The room temperature ferromagnetic graphyne material of the present invention is not limited to the field of wave absorption. The present invention can be used as an infrared stealth material, a super hydrophobic material, a gas sensor material, a secondary battery electrode material, a light and electrocatalytic material, etc. Within the principles of the present invention, any modification, equivalent replacement, improvement, etc. that does not deviate from the technical scheme of the present invention and is applied to any field is an act of infringing the protection scope of the present invention and is included in the protection scope of the present invention.

Claims

1. A large-scale preparation method of room temperature ferromagnetic graphyne material, characterized in that: The following steps are involved: Step 1, taking calcium carbide and hexabromobenzene in a molar ratio of (4-8): 1 and placing them in a ball mill for ball milling. After the completion, taking out the sample, filtering and drying, and annealing at 350-600° C. for 2-6 hours under argon protection to obtain a coarse sample, washing and drying the coarse sample to obtain a semi-finished ferromagnetic graphyne; Step 2: The semi-finished ferromagnetic gydne obtained in step 1 is subjected to secondary annealing at 650-1000° C. for 2-6 hours under argon protection to obtain a finished ferromagnetic gydne material.

2. The large-scale preparation method of room temperature ferromagnetic graphyne material according to claim 1, characterized in that: The grinding balls in the ball mill described in step 1 are made of zirconium oxide, agate or stainless steel, and anhydrous ethanol is used as the solvent; The ratio of the total mass of the grinding balls to the calcium carbide and the hexabromobenzene is (9-15):1; the ball milling process is to perform ball milling at a speed of 500-550 revolutions per minute for 16-24 hours.

3. The large-scale preparation method of room temperature ferromagnetic graphyne material according to claim 1, characterized in that: The washing in step 1 is washing with 0.5-1 mol / L dilute nitric acid, deionized water and anhydrous ethanol 2-3 times in sequence.

4. A room temperature ferromagnetic graphyne material prepared by the method according to any one of claims 1 to 3, characterized in that: The shape is a multi-fold layer stacking structure, with a loose density of 35-45kg / m 3 .

5. A use of the room temperature ferromagnetic graphyne material as claimed in claim 4 in a microwave absorber, characterized in that: The room temperature ferromagnetic graphyne material and paraffin are mixed in a mass ratio of 1:9, homogenized and then pressed to obtain a room temperature ferromagnetic graphyne material microwave absorbing coating, wherein the coating has a thickness of 1.8 to 2.28 mm.

6. An application of the room temperature ferromagnetic graphyne material as claimed in claim 4 in infrared stealth materials, ultraviolet protection materials and optical materials.

7. An application of the room temperature ferromagnetic graphyne material as claimed in claim 4 in gas sensor materials, photoelectrocatalytic materials, adsorption materials, superhydrophobic materials, secondary battery electrode materials, and as a semiconductor material in the manufacture of electronic components, spintronic devices, integrated circuit chips and circuit systems.

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