Preparation method and application of copper molybdate nano material
The preparation of copper molybdate nanomaterials via a one-step hydrothermal method solves the high-temperature and high-cost problems of existing lithium-ion battery gas sensor materials, realizes low-temperature and high-efficiency lithium-ion battery gas monitoring, and provides a high-performance sensor material option.
Patent Information
- Application Number
- CN202511179027.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-22
- Publication Date
- 2025-11-11
AI Technical Summary
Existing lithium-ion battery gas sensor materials, such as metal oxide semiconductor materials, suffer from problems such as high operating temperature, high cost, and long synthesis time, which limit their application in battery thermal runaway monitoring scenarios.
Copper molybdate nanomaterials were prepared by a one-step hydrothermal method. By using hexadecyltrimethylammonium bromide to promote uniform mixing of reactants and form uniform nanoparticles, the working temperature was reduced, and the synthesis was carried out in a neutral pH environment, resulting in high-purity, well-crystallized ellipsoidal particles.
We have achieved low-cost, low-energy preparation of high-performance copper molybdate nanomaterials, with the operating temperature reduced to 120℃. This makes them suitable for monitoring the gas generation behavior of lithium-ion batteries, expanding the application scenarios of the sensor and reducing power consumption.
Smart Images
Figure CN120922919A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of inorganic nanomaterials technology, specifically relating to a method for preparing copper molybdate nanomaterials and their applications. Background Technology
[0002] Lithium-ion batteries, as a green and clean secondary energy storage device, are widely used in electric vehicle power batteries, energy storage power stations, and electronic products. However, in recent years, accidents caused by lithium-ion battery explosions have been frequent, causing great public concern about the safety of lithium-ion batteries, which has hindered their application to some extent.
[0003] Studies have shown that monitoring the gas generation behavior of lithium-ion batteries using gas sensors can evaluate their thermal runaway process and provide safety warnings for such situations. During thermal runaway in lithium-ion batteries, the melting of the separator and the decomposition of the positive and negative electrode materials and electrolyte generate a large amount of gas, such as hydrogen (H2), carbon monoxide (CO), carbon dioxide (CO2), and methane (CH4). Detecting the concentration of these gases using gas sensors can determine the progress of the battery's thermal runaway and provide safety warnings.
[0004] Currently, the market size of gas sensors is growing rapidly. According to data, the global gas sensor industry market size is expected to be approximately US$1.53 billion in 2024 and US$2.52 billion in 2029. Among them, semiconductor gas sensors account for the largest share of the market, approximately 36.83%, followed by electrochemical gas sensors, accounting for approximately 23.22%.
[0005] Gas sensors can be classified into six types based on their working principle: catalytic combustion, electrochemical, thermal conductivity, quartz crystal microbalance, infrared, and resistive gas sensors. Among them, resistive gas sensors are widely used due to their good stability and sensitivity. However, currently mature gas sensor materials, such as metal oxide semiconductor materials ZnO and SnO2, generally have drawbacks such as high operating temperature (200-350℃) and high material synthesis cost (hydrothermal reaction time 8-24h), which limit their application in battery thermal runaway monitoring scenarios. Summary of the Invention
[0006] In view of this, the purpose of this invention is to provide a method for preparing copper molybdate nanomaterials and their applications.
[0007] To achieve the above objectives, the present invention provides the following technical solution:
[0008] This invention provides a method for preparing copper molybdate nanomaterials, the method comprising the following steps:
[0009] S1. Dissolve copper salt and sodium molybdate dihydrate in deionized water to obtain copper chloride solution and sodium molybdate dihydrate solution, respectively.
[0010] S2. Mix the copper chloride solution with the sodium molybdate dihydrate solution and stir thoroughly until homogeneous.
[0011] S3. Then add hexadecyltrimethylammonium bromide and stir until homogeneous, then transfer to a reaction vessel;
[0012] S4. After sealing the reactor, transfer it to an oven and react at 170-200℃.
[0013] S5. Transfer the product to a centrifuge tube, centrifuge it several times with deionized water and anhydrous ethanol in sequence, and then transfer it to a forced-air drying oven to dry at 60°C.
[0014] S6. After thorough drying, the product is ground into a fine powder in a mortar, transferred to a crucible, placed in a muffle furnace, slowly heated and then kept warm, and finally cooled naturally to obtain copper molybdate nanomaterials.
[0015] Furthermore, in step S1, the copper salt is any one of copper chloride, copper hydroxide, copper iodide, and copper acetate.
[0016] Furthermore, the copper salt in step S1 is copper chloride.
[0017] Further, in step S1, the molar ratio of the copper salt to sodium molybdate dihydrate is 0.9-1.1:0.9-1.1.
[0018] Furthermore, in step S4, the reaction time in the reactor in the oven is 4.5-5.5 hours.
[0019] Furthermore, in step S5, the drying time is 11-13 hours.
[0020] Furthermore, in step S5, the heating conditions are as follows: the temperature is increased to 480-520℃ at a rate of 2.5℃ / min and held at that temperature for 4.5-5.5 hours.
[0021] Furthermore, the copper molybdate nanomaterial is used to prepare a sensor, and the preparation steps of the sensor are as follows:
[0022] P1. Take copper molybdate nanomaterial powder into a mortar, add deionized water, and grind it into a uniform slurry using the mortar.
[0023] P2. The slurry is evenly coated onto the sensor carrier loaded with gold interdigitated electrodes;
[0024] P3. Next, place the sensor in a 60℃ oven to dry the moisture, and then transfer it to a sensor aging stage. Aging it at 60℃ for 48 hours to obtain the sensor.
[0025] The beneficial effects of this invention are as follows:
[0026] 1. The copper molybdate nanomaterial of the present invention has low preparation cost and is prepared by a one-step hydrothermal method. The preparation process is simple, time-saving, energy-saving, does not require other strong acid or strong base reagents, and has low equipment requirements.
[0027] 2. The copper molybdate nanomaterial of the present invention has a high specific capacitance value. The addition of hexadecyltrimethylammonium bromide can reduce the surface tension of the reaction system, promote the uniform mixing and dispersion of the reactants, and help to form more uniform and well-dispersed nanoparticles, thereby improving the purity and crystallinity of the product. At the same time, the addition of hexadecyltrimethylammonium bromide can also shorten the reaction time, increase the yield per unit time, and reduce the preparation cost.
[0028] 3. The copper molybdate nanomaterial of this invention has a low operating temperature. The material has a significant response to low concentrations of CO at 120°C. Compared with the optimal operating temperature of widely used metal oxide semiconductor materials, the operating temperature of this material is significantly lower. This not only makes it suitable for applications that monitor the gas production behavior of lithium-ion batteries, but also reduces the power consumption of the sensor and expands its application scenarios.
[0029] 4. This invention uses sodium molybdate instead of ammonium molybdate as the molybdenum source, allowing the hydrothermal reaction to occur in a neutral pH environment. This eliminates the need for other reagents to adjust the pH, simplifying the preparation steps and optimizing the material morphology. In this invention, the copper chloride used will produce H₂ during hydrolysis. + If ammonium molybdate is used as the molybdenum source, the reaction solution will be acidic, easily forming plate-like or band-like molybdate morphologies. The acidic environment will exacerbate the formation of molybdenum oxide components. In contrast, this invention uses ammonium molybdate as the molybdenum source, which generates ammonium copper molybdate during the hydrothermal reaction. Ammonium copper molybdate is highly sensitive to the pH of the solution and will transform into basic copper molybdate with different morphologies. The sodium molybdate used in this invention is a strong base-weak acid salt, and its hydrolysis produces a slightly alkaline reaction, which can neutralize the H+ produced by the hydrolysis of copper chloride. + This allows the reaction to proceed in a neutral pH environment, and MoO4 2- Directly with Cu 2+ The reaction produces no other intermediate products, and the prepared material consists of ellipsoidal particles with a diameter of 100-500 nm. These particles have a large specific surface area, stable morphology, high purity, and high crystallinity, which can effectively improve their gas-sensing performance.
[0030] 5. By controlling the hydrothermal time, this invention screened out the copper molybdate sample prepared at 180℃ for about 5 hours to show the best response performance to CO. The raw materials are inexpensive, the reaction conditions are mild, and the energy consumption is low. It can be directly used for industrial-scale production, providing a high-performance material option for energy storage and catalysis.
[0031] Other advantages, objectives, and features of the invention will be set forth in the following description and will be apparent to those skilled in the art in some respects, or may be learned by practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description
[0032] To make the purpose, technical solution, and beneficial effects of the invention clearer, the following figures are provided for illustration:
[0033] Figure 1 The image shows the morphology of the copper molybdate nanomaterials prepared in Example 1 of this invention using an electron scanning microscope.
[0034] Figure 2 A comparison of the X-ray diffraction pattern of copper molybdate nanomaterial in Example 1 of the present invention (top) and the conventional X-ray diffraction pattern of copper molybdate (bottom);
[0035] Figure 3 The results show the response of the copper molybdate nanomaterials prepared in Examples 1-5 of this invention to different concentrations of CO gas at 120°C. Detailed Implementation
[0036] This invention provides a method for preparing copper molybdate nanomaterials and their applications.
[0037] Example 1
[0038] S1. Dissolve 0.0025 mol of copper chloride and 0.0025 mol of sodium molybdate dihydrate in 30 mL of deionized water to obtain copper chloride solution and sodium molybdate dihydrate solution, respectively.
[0039] S2. Mix the copper chloride solution with the sodium molybdate dihydrate solution and stir thoroughly until homogeneous.
[0040] S3. Then add polyethylene glycol and stir, then add hexadecyltrimethylammonium bromide and continue stirring, and transfer to a reaction vessel;
[0041] S4. After sealing the reactor, transfer it to an oven and react at 180°C for 5 hours;
[0042] S5. Transfer the product to a centrifuge tube, centrifuge it several times with deionized water and anhydrous ethanol in sequence, and then transfer it to a forced-air drying oven to dry at 60°C for 12 hours.
[0043] S6. After thorough drying, the product is ground into a fine powder in a mortar, transferred to a crucible, placed in a muffle furnace, heated to 500℃ at 2.5℃ / min and held for 5 hours, and finally cooled naturally to obtain copper molybdate nanomaterials.
[0044] The sensor is fabricated using copper molybdate nanomaterials, and the specific steps are as follows:
[0045] P1. Take 5mg of copper molybdate nanomaterial powder into a mortar, add 2-3 drops of deionized water, and grind it into a uniform slurry using the mortar.
[0046] P2. The slurry is evenly coated onto the sensor carrier loaded with gold interdigitated electrodes;
[0047] P3. Next, place the sensor in a 60℃ oven to dry the moisture, and then transfer it to a sensor aging stage. Aging it at 60℃ for 48 hours to obtain the sensor.
[0048] The scanning electron microscope image of the copper molybdate nanomaterials prepared in this embodiment is shown below. Figure 1 As shown, after heat treatment, copper molybdate nanomaterials exhibit ellipsoidal or columnar particles with a size of 100-500 nm.
[0049] Figure 2 The image shows a comparison between the X-ray diffraction pattern of the copper molybdate nanomaterial prepared in this embodiment (top) and the conventional copper molybdate X-ray diffraction pattern (bottom).
[0050] To demonstrate the superiority of the reaction time of the present invention, Comparative Examples 1-4 are provided.
[0051] Comparative Example 1
[0052] The difference between Comparative Example 1 and Example 1 is as follows:
[0053] In step S4, the reaction vessel is sealed and transferred to an oven, where it is reacted at 180°C for 0.5 hours. The rest of the process is the same as in Example 1.
[0054] Comparative Example 2
[0055] The difference between Comparative Example 2 and Example 1 is as follows:
[0056] In step S4, the reaction vessel is sealed and transferred to an oven, where it is reacted at 180°C for 2 hours. The rest of the process is the same as in Example 1.
[0057] Comparative Example 3
[0058] The difference between Comparative Example 3 and Example 1 is as follows:
[0059] In step S4, the reaction vessel is sealed and transferred to an oven, where it is reacted at 180°C for 8 hours. The rest of the process is the same as in Example 1.
[0060] Comparative Example 4
[0061] The difference between Comparative Example 4 and Example 1 is as follows:
[0062] In step S4, the reaction vessel is sealed and transferred to an oven, where it is reacted at 180°C for 10 hours. The rest of the process is the same as in Example 1.
[0063] The test used an intelligent gas mixing system (DGD-V, Elite Tech) to dilute 2% CO gas (with N2 as the diluent) to a specific concentration using artificial air (21% O2, 79% N2) as the background gas. The response of the sensor was calculated by collecting the resistance values of the sensor before and after exposure to the CO gas atmosphere.
[0064] The sensor's response is defined as:
[0065]
[0066] Where R a R is the resistance value of the sensor in the background gas. g This represents the resistance value of the sensor in a target gas at a specific concentration.
[0067] The copper molybdate nanomaterials prepared in Example 1, Comparative Examples 1-4 were tested to assess their response to different concentrations of CO gas at 120°C. The results are as follows: Figure 3 As shown:
[0068] The copper molybdate nanomaterial prepared in Example 1, reacted at 180°C for 5 hours, exhibited the best CO response. Under test conditions at 120°C, Example 1 showed a 25.17% response to 20 ppm CO and a 59.32% response to 500 ppm CO, demonstrating its performance advantage in these temperature ranges. In contrast, the copper molybdate nanomaterials prepared in Comparative Examples 1-4 all showed poor responses.
[0069] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made to it in form and detail without departing from the scope defined by the claims of the present invention.
Claims
1. A method for preparing copper molybdate nanomaterials, characterized in that: The method includes the following steps: S1. Dissolve copper salt and sodium molybdate dihydrate in deionized water to obtain copper chloride solution and sodium molybdate dihydrate solution, respectively. S2. Mix the copper chloride solution with the sodium molybdate dihydrate solution and stir thoroughly until homogeneous. S3. Then add hexadecyltrimethylammonium bromide and stir until homogeneous, then transfer to a reaction vessel; S4. After sealing the reactor, transfer it to an oven and react at 170-200℃. S5. Transfer the product to a centrifuge tube, centrifuge it several times with deionized water and anhydrous ethanol in sequence, and then transfer it to a forced-air drying oven to dry at 60°C. S6. After thorough drying, the product is ground into a fine powder in a mortar, transferred to a crucible, placed in a muffle furnace, slowly heated and then kept warm, and finally cooled naturally to obtain copper molybdate nanomaterials.
2. The method for preparing copper molybdate nanomaterials according to claim 1, characterized in that: In step S1, the copper salt is any one of copper chloride, copper hydroxide, copper iodide, and copper acetate.
3. The method for preparing copper molybdate nanomaterials according to claim 2, characterized in that: The copper salt in step S1 is copper chloride.
4. The method for preparing copper molybdate nanomaterials according to claim 1, characterized in that: In step S1, the molar ratio of the copper salt to sodium molybdate dihydrate is 0.9-1.1:0.9-1.
1.
5. The method for preparing copper molybdate nanomaterials according to claim 1, characterized in that: In step S4, the reaction time in the oven is 4.5-5.5 hours.
6. The method for preparing copper molybdate nanomaterials according to claim 1, characterized in that: In step S5, the drying time is 11-13 hours.
7. The method for preparing copper molybdate nanomaterials according to claim 1, characterized in that: In step S5, the heating conditions are as follows: the temperature is increased to 480-520℃ at a rate of 2.5℃ / min and held at that temperature for 4.5-5.5 hours.
8. The copper molybdate nanomaterial according to any one of claims 1-7 is used in the preparation of a sensor, wherein the preparation steps of the sensor are as follows: P1. Take copper molybdate nanomaterial powder into a mortar, add deionized water, and grind it into a uniform slurry using the mortar. P2. The slurry is evenly coated onto the sensor carrier loaded with gold interdigitated electrodes; P3. Next, place the sensor in a 60℃ oven to dry the moisture, and then transfer it to a sensor aging stage. Aging it at 60℃ for 48 hours to obtain the sensor.