Hollow sphere electronic packaging material and preparation method thereof

Abstract

The application discloses a hollow spherical electronic packaging material and a preparation method thereof, relates to the field of electronic packaging material preparation, and discloses a preparation method of the hollow spherical Cu2V2O7 material, which comprises the following steps: preparing a copper ion solution A and a vanadium ion solution B by using deionized water as a solvent; mixing the solution A and the solution B to obtain a precursor solution; adding the precursor solution into an atomization generating device to atomize the precursor solution into droplets; introducing inert gas into a gas inlet pipe of the atomization generating device; and feeding the droplets into a preheated tubular furnace to be calcined, wherein the calcination temperature is 630-700 DEG C, the calcination time is 4-10 h, and the hollow spherical Cu2V2O7 product is collected in a quartz tube. The application solves the technical problems of the existing electronic packaging technology, such as the defects of inorganic fillers, such as complex preparation process, insufficient mechanical properties, high cost and poor environmental protection, and the low structural reliability caused by the mismatch of the thermal expansion coefficients of the packaging material and the epoxy resin after compounding.

Description

Technical Field

[0001] This invention relates to the field of electronic packaging material preparation, specifically to a hollow spherical electronic packaging material and its preparation method. Background Technology

[0002] As microelectronic packaging technology advances towards higher density, miniaturization, and higher reliability, flip-chip packaging has become one of the mainstream technologies. In this structure, the underfill adhesive plays a crucial role. By filling the gap between the chip and the substrate, it effectively alleviates stress concentration caused by the mismatch of coefficients of thermal expansion (CTE), thereby improving solder joint reliability and device lifespan.

[0003] Currently, the most widely used underfill adhesives are mainly based on epoxy resin. However, epoxy resin itself has a high coefficient of thermal expansion (typically greater than 60 × 10⁻⁶). -6 The temperature of ℃ can easily lead to interfacial delamination in the packaging structure during thermal cycling, causing signal transmission loss and device leakage. To reduce the coefficient of thermal expansion, a large amount of silica (SiO2) filler is usually required (the filler content is often higher than 60 wt%). However, a high silica filler content will cause the viscosity of the composite material to increase sharply, the flow and filling performance to decrease, the fracture toughness to decrease, and the interfacial bonding to weaken, which will affect the overall reliability of the packaging.

[0004] In recent years, negative thermal expansion materials have provided a new approach for precise control of thermal expansion. Cu₂V₂O₇, as a typical negative thermal expansion compound, exhibits significant volume shrinkage behavior within a specific temperature range, theoretically making it highly suitable for regulating the thermal expansion properties of epoxy resins. To further optimize the negative thermal expansion properties of Cu₂V₂O₇ through multiple methods, attempts have been made to modify the material through ion doping, such as introducing Zn. 2+ Partial substitution of Cu 2+ It can not only control the negative thermal expansion coefficient, but also has the potential to improve its compatibility with polymer matrices.

[0005] Furthermore, the morphology of the filler has a particularly significant impact on the properties of the composite material. Compared to existing Cu2V2O7 fillers, which are mostly irregular in shape or solid microparticles, hollow spherical structures, due to their high specific surface area, low density, and controllable pore structure, show potential advantages in enhancing filler-matrix interface interactions, promoting stress dispersion, and improving thermal and mechanical properties. Meanwhile, Zn... 2+ The combination of doping and hollow spherical structure theoretically allows for the coordinated optimization of the negative thermal expansion properties of Cu₂V₂O₇. This can be achieved by modifying Zn... 2+The content of the filler can be adjusted to control the negative thermal expansion coefficient and the interfacial bonding force. A milder negative thermal expansion coefficient helps with compatibility with the matrix. Simultaneously, fillers with different NTE coefficients can achieve more precise "thermal expansion compensation." Although hollow spherical Cu2V2O7 theoretically has the advantage of synergistically achieving low thermal expansion, lightweight, and good mechanical properties, there are currently no publicly available reports on its controllable preparation and application in polymer-based composites.

[0006] In summary, the main problems with underfill adhesives in existing microelectronic packaging technologies are as follows:

[0007] 1. Cost and Environmental Issues of Inorganic Filler Synthesis: In existing epoxy molding compounds (EMC) for electronic packaging, the mainstream inorganic filler is amorphous silica, whose synthesis requires temperatures above 2500 ℃, directly resulting in high equipment costs, high energy consumption, and significant carbon emissions. While other commonly used fillers (such as AlN, graphene, BN, etc.) have excellent performance, their high raw material costs or complex processing technologies further increase the economic burden of industrial applications.

[0008] 2. Structural reliability issues caused by thermal expansion mismatch: The coefficient of thermal expansion (CTE) of epoxy resin is as high as several hundred (10). -6 / ℃, while silicon chips (2.5×10 -6 / ℃), copper microbumps (17×10) -6 / ℃), organic substrate (24×10) -6 The CTE (chemical effluent temperature) varies significantly with temperature (°C). Existing fillers (such as silica) have a CTE of ~0.5 × 10⁻⁶. -6 While the temperature (°C) can reduce the CTE of composite materials, it is difficult to accurately match the thermal expansion requirements of various components, resulting in mechanical deformations such as lamination, cracking, and warping caused by temperature changes in 3D packaging, which affects the long-term reliability of integrated circuits (ICs). Summary of the Invention

[0009] To address the problems existing in the prior art, the present invention aims to provide a hollow spherical electronic packaging material and its preparation method, which solves the defects of inorganic fillers in the existing electronic packaging technology, such as complex preparation process, insufficient mechanical properties, high cost and poor environmental performance, as well as the technical problems of low structural reliability caused by the mismatch of thermal expansion coefficients after the packaging material is compounded with epoxy resin.

[0010] The present invention is implemented using the following technical solutions:

[0011] A method for preparing hollow spherical Cu2V2O7 material includes the following steps:

[0012] Step 1: Prepare copper ion solution A using deionized water as a solvent. The concentration of copper ion solution A is 0.15~0.20 mol / L.

[0013] Step 2: Prepare vanadium ion solution B using deionized water as solvent, wherein the concentration of vanadium ion solution B is 0.15~0.20 mol / L;

[0014] Step 3: Mix solution A prepared in step 1 and solution B prepared in step 2. The ratio of solution A to solution B is 1:1 according to a molar ratio meter to obtain a suspension. Adjust the pH of the suspension to 2-3 with nitric acid solution until the solution is clear to obtain a precursor solution. The molar ratio of solute HNO3 in the nitric acid solution to vanadium ions in solution B is 1:2.

[0015] Step 4: Add the precursor solution obtained in step 3 to the atomizing device to atomize the precursor solution into droplets. The total atomization rate of the atomizing device is 1800-2400 mL / h, and the ultrasonic frequency of each atomizer is 1.75MHz.

[0016] Step 5: Inert gas is introduced into the air inlet pipe of the atomizing device at a flow rate of 6 L / min. The droplets described in Step 4 are fed into a preheated tubular furnace for calcination at a temperature of 630-700 °C for 4-10 h. Hollow spherical Cu2V2O7 products are collected in a quartz tube.

[0017] Hollow spherical Cu2V2O7 material was obtained according to the above preparation method.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] The droplets of this invention have a high ion concentration. When the droplets enter the high-temperature reaction zone, the surface solvent evaporates instantly, and the solute rapidly precipitates and coalesces on the droplet surface to form an initial shell. Because the gas velocity is suitable, the generated gas pressure can support the initial shell and maintain its hollow structure. Simultaneously, due to the large number of droplets, some droplets fuse to form larger spheres due to surface contact. Finally, as water and gas further escape, pores are left on the shell surface, resulting in a Cu2V2O7 filler with a specific hollow spherical structure. Compared with conventional positive expansion fillers, Cu2V2O7 has a negative coefficient of thermal expansion. After being combined with resin, it can effectively reduce and control the coefficient of thermal expansion of the composite material. At the same time, it can reduce the filler content, thereby improving the flowability of the composite material. This is achieved by doping with Zn. 2+ It can regulate Cu 2-x Zn xThe negative coefficient of thermal expansion of V₂O₇ reduces its absolute value. A smaller difference in thermal expansion between the filler and the matrix results in lower residual stress at the interface, leading to better long-term stability and fatigue resistance of the material. The prepared hollow spherical Cu₂V₂O₇ exhibits a wide particle size distribution, directly achieving multi-gradation, high filling rate, and good flowability. The hollow spherical Cu₂V₂O₇ possesses a good Young's modulus, which is beneficial for improving the mechanical properties of resin-filled composites. The hollow spherical structure, with its high specific surface area, low density, and partially porous structure, provides more interaction sites with the resin, enhancing the bonding between the filler and the resin and improving encapsulation reliability. This invention provides a novel solution to the problem of high coefficient of thermal expansion in epoxy resin-based composites, surpassing traditional silica fillers.

[0020] The negative thermal expansion property of the hollow spherical Cu₂V₂O₇ prepared by this invention can be obtained from variable-temperature XRD (X-ray diffraction) data, with a volume expansion coefficient of -17.8 × 10⁻⁶. -6 / ℃ (25-250 ℃), the coefficient of linear expansion is -5.33×10 -6 / ℃ (25-250 ℃). Meanwhile, the hollow spherical Cu2V2O7 exhibits good rigidity, with an initial Young's modulus of approximately 140.3 GPa. When combined with resin, the hollow spherical Cu2V2O7 filler, compared to existing positive expansion fillers (SiO2, Al2O3, BN), can effectively control the thermal expansion behavior of the system at lower filling amounts.

[0021] Hollow spherical Cu prepared by this invention 1.8 Zn 0.2 The negative thermal expansion property of V₂O₇ was obtained from variable-temperature XRD data, with a volumetric expansion coefficient of -13.6 × 10⁻⁶. -6 / ℃ (25-275 ℃), the coefficient of linear expansion is -4.53×10 -6 / ℃ (25-275℃). With Zn 2+ With the increase in proportion, Cu 2-x Zn x The absolute value of the negative thermal expansion coefficient of V₂O₇ will decrease, and may even approach zero expansion. Zn 2+ The introduction of Zn enhances the rigidity of the crystal structure and suppresses the variability of the key structural unit driving negative thermal expansion—the [V₂O₇] bitetrahedron. 2+ Having stable d 10 Electronic configuration increases the overall rigidity of the metal-oxygen chain. Zn 2+ The stronger or more oriented bond with the oxygen atom allows it to more effectively "anchor" the [V₂O₇] ditetrahedron it is attached to. This directly restricts the free rotation of the VO₄ tetrahedron around the bridging oxygen atom and also inhibits the significant shortening of the V–O bridging bond. Therefore, changing the Zn... 2+Concentration can be controlled by Cu 2- x Zn x The coefficient of thermal expansion of V2O7.

[0022] This invention utilizes an ultrasonic spray pyrolysis method to prepare Cu, a negative thermal expansion material. 2-x Zn x V₂O₇ is a hollow sphere with a particle size of 0.73 mm. With a particle size of 0.21 μm, it exhibits a wide distribution, conforms to multi-gradation, and can achieve ultra-high filling rates. It also possesses high fluidity and low density, making it suitable for practical applications. Furthermore, Cu... 2-x Zn x V2O7 has a low synthesis temperature (<700 ℃), low cost, and is environmentally friendly. Compared with traditional high-energy-consuming silica fillers, it can reduce the energy consumption and carbon emissions in material preparation. It provides a new technical path for developing "low-filler, high-performance" lightweight next-generation underfill adhesives, and also provides an important material platform and theoretical and practical basis for the in-depth application of negative thermal expansion materials in the field of electronic packaging.

[0023] Because the products prepared by this invention are limited, in order to verify Cu 2-x Zn x V₂O₇ can indeed reduce the thermal expansion of resins, and Cu can be synthesized via solid-state methods. 1.8 Zn 0.2 V₂O₇, sintered into bulk form by plasma sintering, had a linear expansion coefficient of -10.79 × 10⁻⁶ measured by TMA (thermomechanical analysis). -6 / ℃ (25-250 ℃), in Cu 1.8 Zn 0.2 After mixing V₂O₇ with a PVA (polyvinyl alcohol) solution and pressing it into sheets, the linear expansion of the bulk material was -9.32 × 10⁻⁶. -6 / ℃ (25-200℃). Through Zn 2+ Doping further modulates the negative thermal expansion coefficient, laying the material foundation for ultimately achieving precise thermal expansion matching between the chip and the substrate.

[0024] In summary, by combining the unique morphology of hollow spheres with their negative thermal expansion characteristics, this invention achieves an integrated design of filler structure and performance, providing a novel functional filler solution to address the problems of deteriorated flowability, decreased toughness, and poor interface reliability in epoxy resin-based composite materials caused by traditional encapsulation fillers. Attached Figure Description

[0025] Figure 1The images show the structural and temperature-dependent characterization of the hollow sphere Cu2V2O7 prepared in Example 1 of this invention, where (a) is the room temperature XRD pattern of the hollow sphere Cu2V2O7 prepared in Example 1 of this invention; (b) is the temperature-dependent XRD pattern of the hollow sphere Cu2V2O7 prepared in Example 1 of this invention; and (c) is the cell volume of the hollow sphere Cu2V2O7 prepared in Example 1 of this invention as a function of temperature.

[0026] Figure 2 The images show the microstructure and elemental distribution of the hollow sphere Cu2V2O7 prepared in Example 1 of this invention. (a) is a scanning electron microscope (SEM) image of the hollow sphere Cu2V2O7 prepared in Example 1 of this invention, with a magnification of 10,000x; (b) is a scanning electron microscope (SEM) image of the hollow sphere Cu2V2O7 prepared in Example 1 of this invention, with a magnification of 70,000x; (c), (d), and (e) are surface scan distribution maps of copper, vanadium, and oxygen elements in the hollow sphere Cu2V2O7 prepared in Example 1 of this invention, respectively.

[0027] Figure 3 This is a transmission electron microscope (TEM) image of the hollow Cu2V2O7 spheres prepared in Example 1 of the present invention.

[0028] Figure 4 The stress-strain curve of in-situ mechanical compression of the hollow sphere Cu2V2O7 prepared in Example 1 of this invention.

[0029] Figure 5 This is a particle size distribution diagram of the hollow Cu2V2O7 spheres prepared in Example 1 of the present invention.

[0030] Figure 6 Cu prepared in Example 2 of this invention 2-x Zn x XRD patterns of V2O7 (x=0, 0.2, 0.4, 0.6, 0.8, 1) at room temperature.

[0031] Figure 7 Hollow Cu spheres prepared in Example 2 of this invention 1.8 Zn 0.2 Temperature-dependent structural characterization diagram of V2O7, where (a) is the hollow sphere Cu prepared in Example 2 of this invention. 1.8 Zn 0.2 (a) Temperature-dependent XRD pattern of V2O7; (b) Hollow sphere Cu prepared in Example 2 of this invention. 1.8 Zn 0.2 The cell volume of V2O7 changes with temperature.

[0032] Figure 8 The doped Zn prepared in Example 2 of this invention 2+ Hollow sphere Cu 1.8 Zn 0.2Microstructure and elemental distribution diagram of V2O7, where (a) shows the doped Zn prepared in Example 2 of this invention. 2+ Hollow sphere Cu 1.8 Zn 0.2 Scanning electron microscope image of V2O7; (b), (c), (d), and (e) are respectively images of Zn-doped samples prepared in Example 2 of this invention. 2+ Hollow sphere Cu 1.8 Zn 0.2 Surface scan distribution of copper, zinc, vanadium and oxygen elements in V2O7.

[0033] Figure 9 The doped Zn prepared in Example 3 of this invention 2+ Hollow sphere Cu 1.6 Zn 0.4 Microstructure and elemental distribution diagram of V2O7, where (a) shows the doped Zn prepared in Example 3 of this invention. 2+ Hollow sphere Cu 1.6 Zn 0.4 (a) Scanning electron microscope image of V2O7, magnification 25000x; (b) Doped Zn prepared in Example 3 of this invention. 2+ Hollow sphere Cu 1.6 Zn 0.4 Scanning electron microscope image of V2O7, magnification 300,000; (c), (d), (e), and (f) are hollow Cu spheres prepared in Example 3 of this invention, respectively. 1.6 Zn 0.4 Surface scan distribution of copper, zinc, vanadium and oxygen elements in V2O7.

[0034] Figure 10 The doped Zn prepared in Example 4 of this invention 2+ Hollow sphere Cu 1.4 Zn 0.6 Microstructure and elemental distribution diagram of V2O7, where (a) shows the doped Zn prepared in Example 4 of this invention. 2+ Hollow sphere Cu 1.4 Zn 0.6 Scanning electron microscope image of V2O7; (b), (c), (d), and (e) are hollow Cu spheres prepared in Example 4 of this invention, respectively. 1.4 Zn 0.6 Surface scan distribution of copper, zinc, vanadium and oxygen elements in V2O7.

[0035] Figure 11 The doped Zn prepared in Example 5 of this invention 2+ Hollow sphere Cu 1.2 Zn 0.8 Microstructure and elemental distribution diagram of V2O7, where (a) shows the doped Zn prepared in Example 5 of this invention.2+ Hollow sphere Cu 1.2 Zn 0.8 (a) Scanning electron microscope image of V2O7, magnification 8000x; (b) Doped Zn prepared in Example 5 of this invention. 2+ Hollow sphere Cu 1.2 Zn 0.8 Scanning electron microscope image of V2O7, magnification 200,000; (c), (d), (e), and (f) are hollow Cu spheres prepared in Example 5 of this invention, respectively. 1.2 Zn 0.8 Surface scan distribution of copper, zinc, vanadium and oxygen elements in V2O7.

[0036] Figure 12 The doped Zn prepared in Example 6 of this invention 2+ Microstructure and elemental distribution of hollow sphere CuZnV2O7, where (a) shows the doped Zn prepared in Example 6 of this invention. 2+ Scanning electron microscope image of hollow sphere CuZnV2O7, magnification 11000x; (b) Doped Zn prepared in Example 6 of this invention. 2+ Scanning electron microscope image of hollow sphere CuZnV2O7, magnification 150,000; (c), (d), (e), and (f) are respectively the surface scan distribution diagrams of copper, zinc, vanadium, and oxygen elements in the hollow sphere CuZnV2O7 prepared in Example 6 of this invention.

[0037] Figure 13 Cu 2-x Zn x The thermal expansion properties of V2O7 material and the thermal expansion properties of its composites are shown in the test diagram, where (a) is Cu 2-x Zn x (a) Negative expansion data of V2O7; (b) Cu 2-x Zn x Graph showing thermal expansion test data of V2O7 mixed with PVA resin.

[0038] Figure 14 Transmission electron microscopy (TEM) image of the solid spherical Cu2V2O7 product prepared in Comparative Example 1.

[0039] Figure 15 The image shows a scanning electron microscope (SEM) image of the solid spherical Cu2V2O7 product prepared in Comparative Example 2. Detailed Implementation

[0040] The present invention will be further described in detail below with reference to specific embodiments. These descriptions are for explanation purposes only and are not intended to limit the scope of the invention.

[0041] This invention provides a controllable synthesis method for hollow spherical Cu2V2O7 materials, addressing the problem that existing technologies cannot prepare Cu2V2O7 materials with specific hollow structures, thus providing a material foundation for subsequent research. (Development of Zn) 2+ Ion-doped hollow Cu spheres 2-x Zn x The preparation process of V2O7 achieves synergistic innovation in ion doping and microstructure control, providing a preparation route for obtaining functional fillers with both a wide negative thermal expansion temperature range and a large negative thermal expansion coefficient.

[0042] Example 1

[0043] The method for preparing hollow spherical Cu2V2O7 material with negative thermal expansion in this embodiment includes the following steps:

[0044] Step 1: Copper ion solution A uses Cu(NO3)·3H2O as the solute and deionized water as the solvent. The concentration of solution A is 0.15 mol / L.

[0045] Step 2: Vanadium ion solution B is prepared using NH4VO3 as solute and deionized water as solvent. The concentration of solution B is 0.15 mol / L.

[0046] Step 3: Mix 500 mL of solution A prepared in Step 1 and 500 mL of solution B prepared in Step 2 to obtain a suspension. Add 10 mL of nitric acid with a mass fraction of 65-68% to adjust the pH of the suspension to 2-3 until the solution is clear to obtain the precursor solution.

[0047] Step 4: Add the precursor solution obtained in Step 3 to the atomizing device to atomize the precursor solution into droplets; the total atomization rate of the atomizing device is 1800 mL / h, and the ultrasonic frequency of each atomizer is 1.75 MHz.

[0048] Step 5: Inert gas is introduced into the air inlet pipe of the atomizing device at a flow rate of 6 L / min. The droplets described in Step 4 are then fed into a preheated tubular furnace for calcination at a temperature of 650 °C for 10 h. Hollow spherical Cu2V2O7 products are collected on the quartz tube wall.

[0049] like Figure 1 As shown, Figure 1 (a) is the room temperature XRD pattern of hollow spherical Cu2V2O7, proving that hollow spherical β-Cu2V2O7 was successfully synthesized; Figure 1 (b) is a variable-temperature XRD pattern. The cell volume at each temperature point can be obtained through refinement. In (c), the cell volume decreases with increasing temperature, and the calculated volumetric expansion coefficient is -17.8 × 10⁻⁶. -6 / ℃ (25-250 ℃), the linear expansion coefficient is 1 / 3 of the volumetric expansion coefficient, therefore the linear expansion coefficient is -5.33×10 -6 / ℃ (25-250 ℃).

[0050] like Figure 2 As shown, Figure 2 (a) Figure 2 (b) is a SEM (scanning electron microscope) image of the nano-hollow spherical β-Cu2V2O7 prepared in this embodiment, wherein... Figure 2 (a) has a magnification of 10,000. Figure 2 (b) has a magnification of 70,000 times, from Figure 2 (a) Figure 2 (b) It can be seen that the β-Cu2V2O7 particles prepared in this embodiment are hollow spheres; at the same time, the sphericity is high. The sphericity was calculated using IPP (professional image analysis software), and the sphericity of the particles prepared in Example 1 was calculated to be 87%. Figure 2 (c) Figure 2 (d) Figure 2 (e) is an EDS (Energy Dispersive X-ray Spectroscopy) plot, derived from... Figure 2 (c) Figure 2 (d) Figure 2 (e) indicates that the spherical substance contains the elements Cu, V, and O, which means that β-Cu2V2O7 was successfully synthesized.

[0051] The TEM (transmission electron microscope) image of the nano-hollow spherical β-Cu2V2O7 prepared in this embodiment is shown below. Figure 3 As shown, by Figure 3 It can be seen that the β-Cu2V2O7 particles prepared in this embodiment are spherical with extremely high hollowness, and are hollow spheres.

[0052] This invention increases the concentrations of copper, zinc, and vanadium ions in the reaction, increases the number of mist generators to 3-4, and improves the overall mist generation rate to 1800-2400 mL / h. The ultrasonic frequency is 1.75 MHz, and the nitrogen gas inlet channel is changed from a single port to a double port, with the gas flow rate further increased to 6 L / min. First, the mist generator atomizes the precursor into droplets. Due to the high ion concentration and low solvent content in the droplets, the surface solvent evaporates instantly when the droplets enter the high-temperature reaction zone, and the solute rapidly precipitates and coalesces on the droplet surface to form an initial shell. Because the gas rate is suitable, the generated gas pressure supports the initial shell, maintaining its hollow structure. Simultaneously, due to the large number of droplets, some droplets fuse to form larger spheres due to surface contact. Finally, as water and gas further escape, pores are left on the shell surface, forming a hollow sphere.

[0053] The in-situ compressive stress-strain curve of the nano-hollow spherical β-Cu2V2O7 prepared in this embodiment is shown in the figure below. Figure 4 As shown, by Figure 4 It can be seen that the hollow spherical β-Cu2V2O7 prepared in this embodiment has good rigidity and a Young's modulus of about 140.3 GPa.

[0054] The particle size distribution of the nano-hollow spherical β-Cu2V2O7 prepared in this embodiment is shown in the figure below. Figure 5 As shown, by Figure 5 It can be seen that the particle size of the hollow spherical β-Cu₂V₂O₇ prepared in this embodiment is 0.73 mm. 0.21 μm, which is a wide distribution and conforms to multi-gradation.

[0055] Example 2

[0056] This example demonstrates the preparation of doped Zn. 2+ Hollow spherical Cu 1.8 Zn 0.2 The V2O7 method includes the following steps:

[0057] Step 1: Copper ion solution a uses Cu(NO3)·3H2O as the solute and deionized water as the solvent. The concentration of solution a is 0.18 mol / L.

[0058] Step 2: Vanadium ion solution b is prepared using NH4VO3 as solute and deionized water as solvent, and the concentration of solution b is 0.2 mol / L;

[0059] Step 3: Zinc ion solution c uses Zn(NO3)2·6H2O as the solute and deionized water as the solvent. The concentration of solution c is 0.02 mol / L.

[0060] Step 4: Mix 500 mL of solution a prepared in Step 1 and 500 mL of solution c prepared in Step 3 to obtain a mixed solution;

[0061] Step 5: Mix the mixed solution prepared in Step 4 with 500 mL of solution b prepared in Step 2. Using a molar ratio meter, the ratio of copper ion solution a: zinc ion solution c: vanadium ion solution b is 9:1:10 to obtain a suspension. Add 15 mL of nitric acid with a mass fraction of 65-68% to adjust the pH of the suspension to 2-3 until the solution is clear to obtain the precursor solution.

[0062] Step 6: Add the precursor solution obtained in step 5 to the atomizing device to atomize the precursor solution into droplets; the total mist generation rate of the atomizing device is 1800 mL / h, and the ultrasonic frequency of each mist generator is 1.75 MHz.

[0063] Step 7: Inert gas is introduced into the air inlet pipe of the atomizing device at a flow rate of 6 L / min. The droplets described in Step 6 are then fed into a preheated tubular furnace for calcination at a temperature of 650 °C for 10 h. Hollow spherical Cu particles are collected on the quartz tube wall. 1.8 Zn 0.2 V2O7.

[0064] The nano-hollow spherical β-Cu prepared in this embodiment 1.8 Zn 0.2 The XRD pattern of V2O7 is shown below. Figure 6 As shown, by Figure 6 It can be seen that the β-Cu prepared in this embodiment... 1.8 Zn 0.2 V2O7 was successfully synthesized.

[0065] like Figure 7 As shown, Figure 7 (a) shows the temperature-varying XRD pattern of hollow spherical Cu2V2O7. The cell volume at each temperature point can be obtained through refinement, such as... Figure 7 As shown in (b), the cell volume decreases with increasing temperature, and the calculated volume expansion coefficient is -13.6 × 10⁻⁶. -6 / ℃ (25-275 ℃), the linear expansion coefficient is 1 / 3 of the volumetric expansion coefficient, therefore the linear expansion coefficient is -4.53×10 -6 / ℃ (25-275 ℃).

[0066] The nano-hollow spherical β-Cu prepared in this embodiment 1.8 Zn 0.2 SEM image of V2O7 as shown below Figure 8 As shown, by Figure 8 (a) It can be seen that the sphericity is high. The sphericity was calculated using IPP software, and the sphericity of the particles prepared in Example 2 was calculated to be 93%. Figure 8 (b) Figure 8 (c) Figure 8 (d) Figure 8 (e) is the EDS plot, from Figure 8 (b) Figure 8 (c) Figure 8 (d) Figure 8 (e) indicates that the spherical substance contains the elements Cu, Zn, V, and O, suggesting that Zn... 2+ Doping successful.

[0067] Example 3

[0068] This example demonstrates the preparation of doped Zn. 2+ Hollow spherical Cu 1.6 Zn 0.4 The V2O7 method includes the following steps:

[0069] Step 1: Copper ion solution a uses Cu(NO3)·3H2O as the solute and deionized water as the solvent. The concentration of solution a is 0.16 mol / L.

[0070] Step 2: Vanadium ion solution b is prepared using NH4VO3 as solute and deionized water as solvent, and the concentration of solution b is 0.2 mol / L;

[0071] Step 3: Zinc ion solution c uses Zn(NO3)2·6H2O as the solute and deionized water as the solvent. The concentration of solution c is 0.04 mol / L.

[0072] Step 4: Mix 500 mL of solution a prepared in Step 1 and 500 mL of solution c prepared in Step 3 to obtain a mixed solution; Step 5: Mix the mixed solution prepared in Step 4 and 500 mL of solution b prepared in Step 2. The ratio of copper ion solution a: zinc ion solution c: vanadium ion solution b is 8:2:10 according to a molar ratio meter to obtain a suspension; add 15 mL of nitric acid with a mass fraction of 65~68% to adjust the pH of the suspension to 2~3 until the solution is clear to obtain the precursor solution;

[0073] Step 6: Add the precursor solution obtained in Step 5 to the atomizing device to atomize the precursor solution into droplets; the total atomization rate of the atomizing device is 1900 mL / h, and the ultrasonic frequency of each atomizer is 1.75MHz.

[0074] Step 7: Inert gas is introduced into the air inlet pipe of the atomizing device at a flow rate of 6 L / min. The droplets described in Step 6 are then fed into a preheated tubular furnace for calcination at a temperature of 650 °C for 10 h. Hollow spherical Cu particles are collected on the quartz tube wall. 1.6 Zn 0.4 V2O7.

[0075] The nano-hollow spherical β-Cu prepared in this embodiment 1.6 Zn 0.4 The XRD pattern of V2O7 is shown below. Figure 6 As shown, by Figure 6 It can be seen that the β-Cu prepared in this embodiment... 1.6 Zn 0.4 V2O7 was successfully synthesized.

[0076] like Figure 9 As shown, Figure 9 (a) Figure 9 (b) The nano-hollow spherical β-Cu prepared in this embodiment 1.6 Zn 0.4 SEM images of V2O7, where Figure 9(a) has a magnification of 25,000. Figure 9 (b) has a magnification of 300,000 times, from Figure 9 (a) Figure 9 (b) It can be seen that the prepared β-Cu 1.6 Zn 0.4 V2O7 is a hollow sphere with high sphericity. The sphericity was calculated using IPP software, and the sphericity of the particles prepared in Example 3 was calculated to be 93%. Figure 9 (c) Figure 9 (d) Figure 9 (e) Figure 9 (f) is the EDS plot, from Figure 9 (c) Figure 9 (d) Figure 9 (e) Figure 9 (f) indicates that the spherical substance contains the elements Cu, Zn, V, and O, suggesting that Zn... 2+ Doping successful.

[0077] Example 4

[0078] This example demonstrates the preparation of doped Zn. 2+ Hollow spherical Cu 1.4 Zn 0.6 The V2O7 method includes the following steps:

[0079] Step 1: The copper ion solution a uses Cu(NO3)·3H2O as the solute and deionized water as the solvent. The concentration of solution a is 0.14 mol / L.

[0080] Step 2: Vanadium ion solution b is prepared using NH4VO3 as solute and deionized water as solvent, and the concentration of solution b is 0.2 mol / L;

[0081] Step 3: Zinc ion solution c uses Zn(NO3)2·6H2O as the solute and deionized water as the solvent. The concentration of solution c is 0.06 mol / L.

[0082] Step 4: Mix 500 mL of solution A prepared in Step 1 and 500 mL of solution C prepared in Step 3 to obtain a mixed solution; Step 5: Mix the mixed solution prepared in Step 4 and 500 mL of solution b prepared in Step 2. The ratio of copper ion solution a: zinc ion solution c: vanadium ion solution b is 7:3:10 according to a molar ratio meter to obtain a suspension; add 15 mL of nitric acid with a mass fraction of 65~68% to adjust the pH of the suspension to 2~3 until the solution is clear to obtain the precursor solution;

[0083] Step 6: Add the precursor solution obtained in step 5 to the atomizing device to atomize the precursor solution into droplets; the total atomization rate of the atomizing device is 2000 mL / h, and the ultrasonic frequency of each atomizer is 1.75 MHz;

[0084] Step 7: Inert gas is introduced into the air inlet pipe of the atomizing device at a flow rate of 6 L / min. The droplets described in Step 6 are then fed into a preheated tubular furnace for calcination at a temperature of 650 °C for 10 h. Hollow spherical Cu particles are collected on the quartz tube wall. 1.4 Zn 0.6 V2O7.

[0085] The nano-hollow spherical β-Cu prepared in this embodiment 1.4 Zn 0.6 The XRD pattern of V2O7 is shown below. Figure 6 As shown, by Figure 6 It can be seen that the β-Cu prepared in this embodiment... 1.4 Zn 0.6 V2O7 was successfully synthesized.

[0086] The nano-hollow spherical β-Cu prepared in this embodiment 1.4 Zn 0.6 SEM image of V2O7 as shown below Figure 10 As shown, by Figure 10 (a) It can be seen that the prepared β-Cu 1.4 Zn 0.6 V2O7 is a hollow sphere with high sphericity. The sphericity was calculated using IPP software, and the sphericity of the particles prepared in Example 4 was calculated to be 98%. Figure 10 (b) Figure 10 (c) Figure 10 (d) Figure 10 (e) is the EDS plot, from Figure 10 (b) Figure 10 (c) Figure 10 (d) Figure 10 (e) indicates that the spherical substance contains the elements Cu, Zn, V, and O, suggesting that Zn... 2+ Doping successful.

[0087] Example 5

[0088] This example demonstrates the preparation of doped Zn. 2+ Hollow spherical Cu 1.2 Zn 0.8 The V2O7 method includes the following steps:

[0089] Step 1: Copper ion solution a uses Cu(NO3)·3H2O as the solute and deionized water as the solvent. The concentration of solution a is 0.12 mol / L.

[0090] Step 2: Vanadium ion solution b is prepared using NH4VO3 as solute and deionized water as solvent, and the concentration of solution b is 0.2 mol / L;

[0091] Step 3: Zinc ion solution c uses Zn(NO3)2·6H2O as the solute and deionized water as the solvent. The concentration of solution c is 0.08 mol / L.

[0092] Step 4: Mix 500 mL of solution a prepared in Step 1 and 500 mL of solution c prepared in Step 3 to obtain a mixed solution;

[0093] Step 5: Mix the mixed solution prepared in Step 4 with 500 mL of solution b prepared in Step 2. The ratio of copper ion solution a: zinc ion solution c: vanadium ion solution b is 6:4:10 according to the molar ratio. A suspension is obtained. Add 15 mL of nitric acid with a mass fraction of 65-68% to adjust the pH of the suspension to 2-3 until the solution is clear to obtain the precursor solution.

[0094] Step 6: Add the precursor solution obtained in step 5 to the atomizing device to atomize the precursor solution into droplets; the total mist generation rate of the atomizing device is 2100 mL / h, and the ultrasonic frequency of each mist generator is 1.75 MHz.

[0095] Step 7: Inert gas is introduced into the air inlet pipe of the atomizing device at a flow rate of 6 L / min. The droplets described in Step 6 are then fed into a preheated tubular furnace for calcination at a temperature of 650 °C for 10 h. Hollow spherical Cu particles are collected on the quartz tube wall. 1.2 Zn 0.8 V2O7.

[0096] The nano-hollow spherical β-Cu prepared in this embodiment 1.2 Zn 0.8 The XRD pattern of V2O7 is shown below. Figure 6 As shown, by Figure 6 It can be seen that the β-Cu prepared in this embodiment... 1.2 Zn 0.8 V2O7 was successfully synthesized.

[0097] like Figure 11 As shown, Figure 11 (a) Figure 11 (b) The nano-hollow spherical β-Cu prepared in this embodiment 1.2 Zn 0.8 SEM images of V2O7, where Figure 11 (a) has a magnification of 8000 times. Figure 11 (b) has a magnification of 200,000 times, from Figure 11 (a) Figure 11 (b) It can be seen that the prepared β-Cu 1.2 Zn 0.8 V2O7 is a hollow sphere with high sphericity. The sphericity was calculated using IPP software, and the sphericity of the particles prepared in Example 5 was calculated to be 97%. Figure 11 (c) Figure 11 (d) Figure 11 (e) Figure 11 (f) is the EDS plot, from Figure 11 (c) Figure 11 (d) Figure 11 (e) Figure 11 (f) indicates that the spherical substance contains the elements Cu, Zn, V, and O, suggesting that Zn... 2+ Doping successful.

[0098] Example 6

[0099] This example demonstrates the preparation of doped Zn. 2+ The method for hollow spherical CuZnV2O7 includes the following steps:

[0100] Step 1: Copper ion solution a uses Cu(NO3)·3H2O as the solute and deionized water as the solvent. The concentration of solution a is 0.1 mol / L.

[0101] Step 2: Vanadium ion solution b is prepared using NH4VO3 as solute and deionized water as solvent, and the concentration of solution b is 0.2 mol / L;

[0102] Step 3: Zinc ion solution c uses Zn(NO3)2·6H2O as the solute and deionized water as the solvent. The concentration of solution c is 0.1 mol / L.

[0103] Step 4: Mix 500 mL of solution a prepared in Step 1 and 500 mL of solution c prepared in Step 3 to obtain a mixed solution;

[0104] Step 5: Mix the mixed solution prepared in Step 4 with 500 mL of solution b prepared in Step 2. Using a molar ratio meter, the ratio of copper ion solution a: zinc ion solution c: vanadium ion solution b is 5:5:10. A suspension is obtained. Add 15 mL of nitric acid with a mass fraction of 65-68% to adjust the pH of the suspension to 2-3 until the solution is clear, thus obtaining the precursor solution.

[0105] Step 6: Add the precursor solution obtained in Step 5 to the atomizing device to atomize the precursor solution into droplets; the total atomization rate of the atomizing device is 2200 mL / h, and the ultrasonic frequency of each atomizer is 1.75 MHz.

[0106] Step 7: Inert gas is introduced into the air inlet pipe of the atomizing device at a flow rate of 6 L / min. The droplets described in Step 6 are sent into a preheated tubular furnace for calcination at a temperature of 650 °C for 10 h. Hollow spherical CuZnV2O7 are collected on the quartz tube wall.

[0107] The XRD pattern of the nano-hollow spherical β-CuZnV2O7 prepared in this embodiment is shown in the figure below. Figure 6 As shown, by Figure 6 It can be seen that the β-CuZnV2O7 prepared in this embodiment was successfully synthesized.

[0108] like Figure 12 As shown, Figure 12 (a) Figure 12 (b) is a SEM image of the nano-hollow spherical β-CuZnV2O7 prepared in this embodiment, wherein... Figure 12 (a) has a magnification of 11,000 times. Figure 12 (b) has a magnification of 150,000 times, from Figure 12 (a) Figure 12 (b) It can be seen that the prepared β-CuZnV2O7 is hollow spheres with high sphericity. The sphericity was calculated using IPP software, and the sphericity of the particles prepared in Example 6 was calculated to be 95%. Figure 12 (c) Figure 12 (d) Figure 12 (e) Figure 12 (f) is the EDS plot, from Figure 12 (c) Figure 12 (d) Figure 12 (e) Figure 12 (f) indicates that the spherical substance contains the elements Cu, Zn, V, and O, suggesting that Zn... 2+ Doping successful.

[0109] Because the product prepared in this application is limited, in order to verify Cu 2-x Zn x V₂O₇ can reduce the thermal expansion of resin, and Cu was synthesized via a solid-state method. 1.8 Zn 0.2 V2O7, Cu was sintered using spark plasma sintering. 1.8 Zn 0.2 V2O7 was sintered into a bulk form, and TMA was tested. The results are as follows: Figure 13 As shown, where Figure 13 (a) The median expansion coefficient is -10.79 × 10⁻⁶. -6 / ℃ (25-250 ℃); Add an appropriate amount of PVA resin to Cu 1.8 Zn 0.2 After mixing the V2O7 powder evenly, the mixture was compressed into tablets, and the TMA results of the mixture were tested as follows. Figure 13 (b) The coefficient of linear expansion is -9.32 × 10⁻⁶. -6 / ℃ (25-200 ℃). This proves that Cu 2-x Zn x V2O7 can reduce the thermal expansion of resin, and through Zn 2+ Doping further modulates the negative thermal expansion coefficient.

[0110] Example 7

[0111] The method for preparing hollow spherical Cu2V2O7 material with negative thermal expansion in this embodiment includes the following steps:

[0112] Step 1: Copper ion solution A is prepared using Cu(CH3COO)2·H2O as solute and deionized water as solvent, with a concentration of 0.20 mol / L. Step 2: Vanadium ion solution B is prepared using NH4VO3 as solute and deionized water as solvent, with a concentration of 0.20 mol / L. Step 3: Solution A prepared in Step 1 and solution B prepared in Step 2 are mixed to obtain a suspension. Nitric acid is added to adjust the pH of the suspension to 2-3 until the solution becomes clear, obtaining a precursor solution. Step 4: The precursor solution obtained in Step 3 is added to an atomizing device to atomize the precursor solution into droplets. The total atomization rate of the atomizing device is 2000 mL / h, and the ultrasonic frequency of each atomizer is 1.75 MHz. Step 5: Inert gas is introduced into the air inlet pipe of the atomizing device at a flow rate of 6 L / min. The droplets described in Step 4 are sent into a preheated tubular furnace for calcination at a temperature of 630°C for 4 hours. Hollow spherical Cu2V2O7 products are collected on the quartz tube wall.

[0113] Example 8

[0114] The method for preparing hollow spherical Cu2V2O7 material with negative thermal expansion in this embodiment includes the following steps:

[0115] Step 1: Copper ion solution A is prepared using CuSO4·5H2O as solute and deionized water as solvent, with a concentration of 0.18 mol / L. Step 2: Vanadium ion solution B is prepared using NH4VO3 as solute and deionized water as solvent, with a concentration of 0.18 mol / L. Step 3: Solution A prepared in Step 1 and solution B prepared in Step 2 are mixed to obtain a suspension. Nitric acid is added to adjust the pH of the suspension to 2-3 until the solution becomes clear, obtaining a precursor solution. Step 4: The precursor solution obtained in Step 3 is added to an atomizing device to atomize the precursor solution into droplets. The total atomization rate of the atomizing device is 2200 mL / h, and the ultrasonic frequency of each atomizer is 1.75 MHz. Step 5: Inert gas is introduced into the air inlet pipe of the atomizing device at a flow rate of 6 L / min. The droplets described in Step 4 are sent into a preheated tubular furnace for calcination at a temperature of 700 °C for 6 h. Hollow spherical Cu2V2O7 products are collected on the quartz tube wall.

[0116] Example 9

[0117] The method for preparing hollow spherical Cu2V2O7 material with negative thermal expansion in this embodiment includes the following steps:

[0118] Step 1: Copper ion solution A is prepared using CuSO4·5H2O as solute and deionized water as solvent, with a concentration of 0.19 mol / L. Step 2: Vanadium ion solution B is prepared using NH4VO3 as solute and deionized water as solvent, with a concentration of 0.19 mol / L. Step 3: Solution A prepared in Step 1 and solution B prepared in Step 2 are mixed to obtain a suspension. Nitric acid is added to adjust the pH of the suspension to 2-3 until the solution becomes clear, obtaining a precursor solution. Step 4: The precursor solution obtained in Step 3 is added to an atomizing device to atomize the precursor solution into droplets. The total atomization rate of the atomizing device is 2400 mL / h, and the ultrasonic frequency of each atomizer is 1.75 MHz. Step 5: Inert gas is introduced into the air inlet pipe of the atomizing device at a flow rate of 6 L / min. The droplets described in Step 4 are sent into a preheated tubular furnace for calcination at a temperature of 660 °C for 8 h. Hollow spherical Cu2V2O7 products are collected on the quartz tube wall.

[0119] Example 10

[0120] This example demonstrates the preparation of doped Zn. 2+ Hollow spherical Cu 1.8 Zn 0.2 The V2O7 method includes the following steps:

[0121] Step 1: Copper ion solution a uses CuSO4·5H2O as the solute and deionized water as the solvent, with a concentration of 0.075 mol / L. Step 2: Vanadium ion solution b uses NH4VO3 as the solute and deionized water as the solvent, with a concentration of 0.15 mol / L. Step 3: Zinc ion solution c uses Zn(CH3COO)2... 2H₂O is the solute, deionized water is the solvent, and the concentration of solution c is 0.015 mol / L; Step 4: Mix solution a prepared in step 1 and solution c prepared in step 3 to obtain a mixed solution; Step 5: Mix the mixed solution prepared in step 4 and solution b prepared in step 2, and the ratio of copper ion solution a: zinc ion solution c: vanadium ion solution b is 9:1:10 according to the molar ratio to obtain a suspension; add nitric acid to adjust the pH of the suspension to 2-3 until the solution is clear to obtain a precursor solution; Step 6: Add the precursor solution obtained in step 5 to the atomizing device to atomize the precursor solution into droplets; the total atomization rate of the atomizing device is 2300 mL / h, and the ultrasonic frequency of each atomizer is 1.75MHz; Step 7: Inert gas is introduced into the air inlet pipe of the atomizing device at a flow rate of 6 L / min, and the droplets obtained in step 6 are sent into a preheated tubular furnace for calcination at a calcination temperature of 630°C. ℃, firing time 4 h, collecting hollow spherical Cu on the quartz tube wall 1.8 Zn 0.2 V2O7.

[0122] Example 11

[0123] This example demonstrates the preparation of doped Zn. 2+ Hollow spherical Cu 1.6 Zn 0.4 The V2O7 method includes the following steps:

[0124] Step 1: Copper ion solution a uses Cu(CH3COO)2·H2O as solute and deionized water as solvent, with a concentration of 0.075 mol / L. Step 2: Vanadium ion solution b uses NH4VO3 as solute and deionized water as solvent, with a concentration of 0.18 mol / L. Step 3: Zinc ion solution c uses ZnSO4·7H2O as solute and deionized water as solvent, with a concentration of 0.1 mol / L. mol / L; Step 4: Mix solution A prepared in step 1 and solution C prepared in step 3 to obtain a mixed solution; Step 5: Mix the mixed solution prepared in step 4 and solution b prepared in step 2. Using a molar ratio meter, the ratio of copper ion solution a: zinc ion solution c: vanadium ion solution b is 8:2:10 to obtain a suspension; add nitric acid to adjust the pH of the suspension to 2-3 until the solution is clear to obtain a precursor solution; Step 6: Add the precursor solution obtained in step 5 to an atomizing device to atomize the precursor solution into droplets; the total atomization rate of the atomizing device is 2400 mL / h, and the ultrasonic frequency of each atomizer is 1.75 MHz; Step 7: Inert gas is introduced into the air inlet pipe of the atomizing device at a flow rate of 6 L / min. The droplets obtained in step 6 are sent to a preheated tubular furnace for calcination at a temperature of 700 ℃ for 8 h. Hollow spherical Cu particles are collected on the quartz tube wall. 1.6 Zn 0.4 V2O7.

[0125] Comparative Example 1

[0126] Step 1: The copper ion solution uses Cu(NO3)·3H2O as the solute and deionized water as the solvent, with a copper ion concentration of 0.09 mol / L. Step 2: The vanadium ion solution uses NH4VO3 as the solute and deionized water as the solvent, with a vanadium ion concentration of 0.09 mol / L. Step 3: The copper ion solution prepared in Step 1 and the vanadium ion solution prepared in Step 2 are mixed to obtain a suspension. Nitric acid is added to adjust the pH of the suspension to 2-3 until the solution becomes clear, obtaining a precursor solution. Step 4: The precursor solution obtained in Step 3 is added to an atomizing device to atomize the precursor solution into droplets. The total atomization rate of the atomizing device is 1800 mL / h, and the ultrasonic frequency of each atomizer is 1.75 MHz. Step 5: Inert gas is introduced into the air inlet pipe of the atomizing device at a flow rate of 6 L / min. The droplets obtained in Step 4 are then fed into a preheated tubular furnace for calcination at a temperature of 650°C. The product was collected at ℃ for 10 h and then deposited on the quartz tube wall.

[0127] Adjust the concentrations of copper ion solution A and vanadium ion solution B, keeping other preparation conditions unchanged. The TEM image of the product obtained in this example is shown below. Figure 14As shown in the figure, the prepared Cu2V2O7 is solid spheres, indicating that by reducing the concentration of the precursor solution and maintaining the mist production rate and gas flow rate, the prepared Cu2V2O7 is solid spheres.

[0128] Comparative Example 2

[0129] Step 1: The copper ion solution uses Cu(NO3)·3H2O as the solute and deionized water as the solvent, with a copper ion concentration of 0.15 mol / L. Step 2: The vanadium ion solution uses NH4VO3 as the solute and deionized water as the solvent, with a vanadium ion concentration of 0.15 mol / L. Step 3: The copper ion solution prepared in Step 1 and the vanadium ion solution prepared in Step 2 are mixed to obtain a suspension. Nitric acid is added to adjust the pH of the suspension to 2-3 until the solution becomes clear, obtaining a precursor solution. Step 4: The precursor solution obtained in Step 3 is added to an atomizing device to atomize the precursor solution into droplets. The total atomization rate of the atomizing device is 300 mL / h, and the ultrasonic frequency of each atomizer is 1.75 MHz. Step 5: Inert gas is introduced into the air inlet pipe of the atomizing device at a flow rate of 1.2 L / min. The droplets obtained in Step 4 are then fed into a preheated tubular furnace for calcination at a temperature of 650°C. The product was collected at ℃ for 10 h and then deposited on the quartz tube wall.

[0130] Adjust the concentrations of copper ion solution A and vanadium ion solution B, keeping other preparation conditions unchanged. The SEM image of the product obtained in this example is shown below. Figure 15 As shown in the figure, the prepared Cu2V2O7 is a solid sphere, indicating that by maintaining the original concentration of the precursor solution and reducing the mist generation rate and gas rate, the prepared Cu2V2O7 is a solid sphere.

Claims

1. A method for preparing hollow spherical Cu2V2O7 material, characterized in that, Includes the following steps: Step 1: Prepare copper ion solution A using deionized water as a solvent. The concentration of copper ion solution A is 0.15~0.20 mol / L. Step 2: Prepare vanadium ion solution B using deionized water as solvent, wherein the concentration of vanadium ion solution B is 0.15~0.20 mol / L; Step 3: Mix solution A prepared in step 1 and solution B prepared in step 2. The ratio of solution A to solution B is 1:1 according to a molar ratio meter to obtain a suspension. The pH of the suspension was adjusted to 2-3 using nitric acid solution until the solution became clear, to obtain the precursor solution. The molar ratio of the solute HNO3 in the nitric acid solution to the vanadium ions in solution B was 1:

2. Step 4: Add the precursor solution obtained in step 3 to the atomizing device to atomize the precursor solution into droplets. The total atomization rate of the atomizing device is 1800-2400 mL / h, and the ultrasonic frequency of each atomizer is 1.75 MHz. Step 5: Inert gas is introduced into the air inlet pipe of the atomizing device at a flow rate of 6 L / min. The droplets described in Step 4 are fed into a preheated tubular furnace for calcination at a temperature of 630-700 °C for 4-10 h. Hollow spherical Cu2V2O7 products are collected in a quartz tube.

2. The method for preparing a hollow spherical Cu2V2O7 material according to claim 1, characterized in that, In step 1, copper ion solution A is prepared using Cu(NO3)·3H2O, Cu(CH3COO)2·H2O, or CuSO4·5H2O, and in step 2, vanadium ion solution B is prepared using NH4VO3.

3. Hollow spherical Cu2V2O7 material obtained by any one of the preparation methods according to claims 1-2.

4. The hollow spherical Cu2V2O7 material according to claim 3, characterized in that, The particle size of the hollow spherical Cu₂V₂O₇ material is 0.73 mm. 0.21 μm.

Images