Preparation method of MOF modified liquid metal nanoparticles
Through directional ultrasonic treatment and amino functional group modification, MOF-modified liquid metal nanoparticles with controllable particle size were prepared, which solved the problems of GLM-NPs oxidation and agglomeration, improved the lubrication performance and stability, and were suitable for water-based lubricants.
Patent Information
- Application Number
- CN202510981175.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-16
- Publication Date
- 2025-09-26
AI Technical Summary
In the existing technology, gallium-based liquid metal nanoparticles (GLM-NPs) are easily oxidized and agglomerated during the preparation process, resulting in poor dispersibility and stability in the base lubricant, affecting the lubrication performance. In addition, the Uio-66 zirconium-based MOF lacks coordination groups for gallium ions, making it difficult to effectively combine with GLM nanoparticles.
UiO-66-NH2 powder and GaInSn liquid metal were stirred and dissolved in anhydrous ethanol using directional ultrasonic treatment. Combined with ultrasonic power and temperature control, core-shell structured GLM-NPs/MOF nanoparticles were formed. By introducing amino functional groups to improve the coordination, MOF-modified liquid metal nanoparticles with controllable particle size were prepared.
The high dispersion stability and excellent lubrication performance of GLM-NPs/MOF nanoparticles were achieved, the friction coefficient and wear rate were reduced, the equipment was simple, the cost was low, and it was suitable for mass production.
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Figure CN120699689A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of nanoparticle additives, and in particular to a method for preparing MOF-modified liquid metal nanoparticles. Background Art
[0002] Nanoparticle additives are a crucial component of high-performance lubricants. They convert sliding friction into rolling friction and fill worn areas with self-repairing properties, significantly reducing friction and wear and improving the stability and lifespan of equipment and mechanical systems. While the performance of various nanoparticle lubricant additives, such as Au, Ag, Cu, TiO2, and SiO2, has been extensively studied, developing new, high-performance nanoparticle additives remains a challenging and valuable endeavor.
[0003] In recent years, novel gallium-based liquid metal nanoparticles (GLM-NPs) have been recognized as a promising nanoparticle additive due to their excellent load-bearing properties, high thermal conductivity, and film-forming ability. Compared to solid nanoparticle additives, they offer advantages such as flexibility, greater load-bearing capacity, and the ability to easily form a protective film on the substrate surface. However, during the preparation process, GLM nanoparticles are susceptible to oxidation and agglomeration (primarily due to interfacial interactions between the nanoparticles), which impairs their dispersibility and stability in base lubricants, hindering lubrication performance (ACS. Appl. Nano Mater., 2020, 3:10115-10122). Studies have shown that surface modification of GLM nanoparticles, such as by grafting polymers such as chitosan onto the GLM nanoparticle surface, can effectively address these agglomeration and oxidation issues. Furthermore, research has found that encapsulating GLM metal nanoparticles within a precisely designed metal-organic framework (MOF) creates a multifunctional core-shell structure, preventing GLM surface oxidation and aggregation. Furthermore, the synergistic interfacial interaction between the GLM nanoparticles and the MOF further enhances lubrication performance (Carbon, 2023, 5:373-382). Wang Peng et al. successfully encapsulated GLM-NPs within a zinc-based MOF, demonstrating that the encapsulated nanoparticles exhibit excellent friction reduction and anti-wear properties (ACS. Appl. Mater. Interfaces, 2023, 15:56192-56202). Furthermore, zirconium-based MOFs composed of zirconium oxide clusters interconnected by rigid organic ligands also exhibit excellent tribological properties (Chem. Mater., 2010, 22: 6632-6640). Uio-66 is currently the most popular Zr-based MOF material. Therefore, if Uio-66 zirconium-based MOF is used to modify GLM-NPs, its lubrication performance may be further improved. However, there are some key technical difficulties in combining Uio-66 zirconium-based MOF with GLM nanoparticles, mainly because: (1) the current mainstream Uio-66 zirconium-based MOF lacks groups that coordinate with gallium ions; (2) the control of surface oxidation and particle size of GLM-NPs nanoparticles modified with Uio-66 zirconium-based MOF. Summary of the Invention
[0004] The technical problem to be solved by the present invention is to provide a method for preparing MOF-modified liquid metal nanoparticles with simple equipment and controllable process.
[0005] To solve the above problems, the present invention discloses a method for preparing MOF-modified liquid metal nanoparticles, which is characterized in that: the method comprises adding UiO-66-NH2 powder and GaInSn liquid metal in a mass ratio of 1:2 to 1:10 to an excess of anhydrous ethanol solvent, stirring and dissolving the mixture, treating the mixture with a directional ultrasonic machine, performing high-speed centrifugal separation, and drying the mixture to a constant weight to obtain GLM-NPs / MOF liquid metal nanoparticles.
[0006] The UiO-66-NH2 powder is prepared by a hydrothermal method. The specific process is as follows: an excess amount of dimethylformamide (DMF) is added to the inner wall of the reactor, and 2-aminoterephthalic acid and ZrCl4 are added in a molar ratio of 1:0.5 to 1:1, and the mixture is shaken evenly using an ultrasonic cleaner; the resulting mixture is placed in an autoclave and reacted at a high temperature of 373 to 403 K for 24 to 36 hours to obtain the powder.
[0007] The GaInSn liquid metal is prepared by the following method: 62-65% Ga, 22-25% In and 10-13% Sn by mass are mixed, placed in a tube furnace, completely melted under a pure argon atmosphere at 200°C, kept warm for 1-2 hours, and then cooled to room temperature.
[0008] The purity of Ga, In and Sn is 99.99%.
[0009] The conditions of the directional ultrasonic treatment are as follows: the ultrasonic power is 300-400W, the ultrasonic time is 30-60min, and the ultrasonic temperature is maintained at 15-30°C.
[0010] The centrifugal separation treatment conditions refer to a centrifugal speed of 5000-10000 rpm and a time of 3-10 min.
[0011] A MOF-modified liquid metal nanoparticle is prepared by the method described above.
[0012] The MOF-modified liquid metal nanoparticles are characterized in that the particle size of the MOF-modified liquid metal nanoparticles is between 20 and 500 nm.
[0013] When the MOF-modified liquid metal nanoparticles are used as additives for water-based lubricants, the addition amount is 0.3-0.9% by mass.
[0014] Compared with the prior art, the present invention has the following advantages: 1. The present invention utilizes the structural design advantages of the UiO-66-NH2 material with coordinated unsaturated metal sites and modular organic connectors, replaces terephthalic acid with 2-aminoterephthalic acid, introduces amino functional groups into the Uio-66 zirconium-based MOF structure, and then utilizes the amino groups to react with GLM nanoparticles Ga 3+ The surface modification was carried out by combining the two ideas, and the molar concentration, reaction temperature and time of 2-aminoterephthalic acid and ZrCl4 were systematically optimized to solve the problem that Uio-66 zirconium-based MOF lacked coordination groups for gallium ions.
[0015] 2. The present invention combines zirconium-based MOF with GLM nanoparticles through directional ultrasound and reasonable control of ultrasonic power and temperature to form a core-shell structure of high-performance GLM-NPs / MOF nanoparticles, thereby solving the problems of surface oxidation and particle size control of Uio-66 zirconium-based MOF-modified GLM-NPs nanoparticles.
[0016] 3. The present invention uses MOF as a ligand to efficiently and conveniently prepare liquid metal nanoparticles, thereby solving the problems of existing liquid metal nanoparticles such as large particle size, poor dispersion stability and poor tribological properties.
[0017] 4. The GLM-NPs / MOF liquid metal nanoparticles prepared by the present invention were dispersed in water. After testing, their lubrication performance was better than that of GLM-NPs liquid metal nanoparticles dispersed in water, which can reduce the friction coefficient and wear rate of the material and has important application value.
[0018] 5. The present invention requires simple equipment, controllable process, low cost, and can be mass-produced. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.
[0020] Figure 1 This is the SEM image of the GLM-NPs / MOF liquid metal nanoparticles prepared in Example 1 of the present invention.
[0021] Figure 2 This is the particle size distribution of the GLM-NPs / MO liquid metal nanoparticles prepared in Example 1 of the present invention.
[0022] Figure 3 TEM image (left) and energy spectrum (right) of GLM-NPs / MOF liquid metal nanoparticles prepared in Example 1 of the present invention.
[0023] Figure 4The friction coefficient (a) and wear rate (b) of GCr15 steel under lubrication with different addition amounts of GLM-NPs / MOF modified water-based lubricant prepared in Example 1 of the present invention. DETAILED DESCRIPTION
[0024] A method for preparing MOF-modified liquid metal nanoparticles comprises adding UiO-66-NH2 powder and GaInSn liquid metal at a mass ratio (g / g) of 1:2 to 1:10 to an excess of anhydrous ethanol solvent, stirring and dissolving the mixture. The mixture is then treated with a directional ultrasonic machine at a power of 300-400W, a duration of 30-60 minutes, and a temperature maintained at 15-30°C. The mixture is then subjected to high-speed centrifugation at a speed of 5000-10000 rpm for 3-10 minutes, and dried at 303-323°C to constant weight to obtain GLM-NPs / MOF liquid metal nanoparticles.
[0025] Among them: UiO-66-NH2 powder is prepared by a hydrothermal method. The specific process is as follows: an excess amount of organic solvent dimethylformamide (DMF) is added to the inner wall of the reactor, and 2-aminoterephthalic acid and ZrCl4 are added in a molar ratio of 1:0.5~1:1, and shaken evenly with an ultrasonic cleaner; the resulting mixture is placed in an autoclave and reacted at a high temperature of 373~403K for 24~36h to obtain the powder.
[0026] GaInSn liquid metal is prepared as follows: 62-65% Ga, 22-25% In, and 10-13% Sn (by weight percentage (g)) are mixed. The mixture is then completely melted in a tube furnace at 200°C under a pure argon atmosphere. The mixture is held at this temperature for 1-2 hours and then cooled to room temperature. The purity of Ga, In, and Sn is 99.99%.
[0027] The particle size of the obtained MOF-modified liquid metal nanoparticles is between 20 and 500 nm.
[0028] When the MOF-modified liquid metal nanoparticles are used as an additive for a water-based lubricant, the addition amount is 0.3-0.9% by mass fraction (g).
[0029] Example 1 A method for preparing GLM-NPs / MOF liquid metal nanoparticles: 0.2g UiO-66-NH2 powder was dissolved in 100ml anhydrous ethanol, and then 1g Ga 65 In 25 Sn 10The liquid metal was stirred and dissolved, then treated with a directional ultrasonic machine at 350W of ultrasonic power and maintained at 20°C for 30 minutes. The mixture was then centrifuged at 5000 rpm for 5 minutes, the supernatant discarded, and dried at 313K to constant weight to obtain GLM-NPs / MOF liquid metal nanoparticles.
[0030] UiO-66-NH2 powder was prepared using a hydrothermal method. The following steps were performed: DMF (80 ml, 1.033 mol), NH2BDC (0.556 g, 0.004 mol), and ZrCl4 (0.772 g, 0.003 mol) were added to the inner wall of a reactor and shaken thoroughly using an ultrasonic cleaner. The resulting mixture was placed in an autoclave and reacted at 393 K for 36 hours. After cooling to room temperature, the mixture was washed with DMF and anhydrous ethanol and centrifuged to obtain a pink precipitate. The supernatant was filtered, and the precipitate, along with anhydrous ethanol, was transferred to the inner wall of the reactor and dried at 373 K for 12 hours. After complete evaporation of the liquid, the mixture was vacuum-dried at 353 K for 12 hours.
[0031] Ga 65 In 25 Sn 10 The liquid metal is prepared as follows: 65g Ga, 25g In and 10g Sn are mixed, placed in a tube furnace, completely melted under pure argon atmosphere at 200°C, kept warm for 1~2h and then cooled to room temperature.
[0032] The obtained GLM-NPs / MOF liquid metal nanoparticles were characterized using scanning electron microscopy. Figure 1 As shown in the figure, it can be found that the liquid metal nanoparticles are spherical and evenly distributed.
[0033] The GLM-NPs / MOF liquid metal nanoparticles were dispersed in anhydrous ethanol and the particle size analysis was performed, such as Figure 2 It can be seen that the particle size of GLM-NPs / MOF liquid metal nanoparticles is between 20nm and 500nm.
[0034] The obtained GLM-NPs / MOF liquid metal nanoparticles were characterized by transmission electron microscopy. Figure 3 As shown in the figure, it can be seen that the GLM-NPs / MOF liquid metal nanoparticles have a core-shell structure.
[0035] The prepared GLM-NPs / MOF liquid metal nanoparticles were prepared into water-based lubricants with mass fractions (g) of 0.3%, 0.6%, and 0.9%. The lubrication performance of the water-based lubricants modified with different amounts of GLM-NPs / MOF was characterized using an SRV friction and wear tester. The friction conditions were GCr15 steel-GCr15 steel, speed 0.2 m / s, and load 100 N-200 N. The wear volume of the material was characterized using a three-dimensional profilometer. The results are shown in Figure 2. Figure 4 As shown in Figure 2, the friction coefficient of GLM-NPs / MOF with an addition amount of 0.6 wt.% remains between 0.175 and 0.186, and the wear rate remains between (3.78 and 7.02)×10 -6 Comparative analysis shows that the friction coefficients of the additive amounts of 0.3 wt.% and 0.9 wt.% are 0.175~0.179 and 0.187~0.192, respectively, and the corresponding wear rates are (5.23~7.45)×10 -6 mm³ / Nm and (4.42~7.37)×10 -6 mm³ / Nm. It can be seen that the GLM-NPs / MOF with an addition amount of 0.6wt.% has the best wear reduction and anti-wear effect.
[0036] Example 2 A method for preparing GLM-NPs / MOF liquid metal nanoparticles: 0.1g UiO-66-NH2 powder was dissolved in 100ml anhydrous ethanol, and then 1g Ga 65 In 25 Sn 10 The liquid metal was stirred and dissolved, then treated with a directional ultrasonic machine at 350W of ultrasonic power and maintained at 20°C for 30 minutes. The mixture was then centrifuged at 5000 rpm for 5 minutes, the supernatant discarded, and dried at 313K to constant weight to obtain GLM-NPs / MOF liquid metal nanoparticles.
[0037] UiO-66-NH2 powder was prepared using a hydrothermal method. The following steps were performed: DMF (80 ml, 1.033 mol), NH2BDC (0.556 g, 0.004 mol), and ZrCl4 (0.772 g, 0.003 mol) were added to the inner wall of a reactor and shaken thoroughly using an ultrasonic cleaner. The resulting mixture was placed in an autoclave and reacted at 393 K for 24 hours. After cooling to room temperature, the mixture was washed with DMF and anhydrous ethanol and centrifuged to obtain a pink precipitate. The supernatant was filtered, and the precipitate, along with anhydrous ethanol, was transferred to the inner wall of the reactor and dried at 373 K for 12 hours. After complete evaporation of the liquid, the mixture was vacuum-dried at 353 K for 12 hours.
[0038] Ga65 In 25 Sn 10 The preparation of liquid metal is the same as in Example 1.
[0039] Example 3 A method for preparing GLM-NPs / MOF liquid metal nanoparticles: 0.5 g of UiO-66-NH2 powder was dissolved in 100 ml of anhydrous ethanol, and then 1.0 g of Ga 65 In 25 Sn 10 The liquid metal was stirred and dissolved, then treated with a directional ultrasonic machine at 350W of ultrasonic power and maintained at 20°C for 30 minutes. The mixture was then centrifuged at 5000 rpm for 5 minutes, the supernatant discarded, and dried at 313K to constant weight to obtain GLM-NPs / MOF liquid metal nanoparticles.
[0040] UiO-66-NH2 powder was prepared using a hydrothermal method. The following steps were performed: DMF (80 ml, 1.033 mol), NH2BDC (0.556 g, 0.004 mol), and ZrCl4 (0.772 g, 0.003 mol) were added to the inner wall of a reactor and shaken thoroughly using an ultrasonic cleaner. The resulting mixture was placed in an autoclave and reacted at 393 K for 24 hours. After cooling to room temperature, the mixture was washed with DMF and anhydrous ethanol and centrifuged to obtain a pink precipitate. The supernatant was filtered, and the precipitate, along with anhydrous ethanol, was transferred to the inner wall of the reactor and dried at 393 K for 12 hours. After complete evaporation of the liquid, the mixture was vacuum-dried at 353 K for 12 hours.
[0041] Ga 65 In 25 Sn 10 The preparation of liquid metal is the same as in Example 1.
Claims
1. A method for preparing MOF-modified liquid metal nanoparticles, characterized by: The method involves adding UiO-66-NH2 powder and GaInSn liquid metal in a mass ratio of 1:2 to 1:10 into an excess of anhydrous ethanol solvent, stirring and dissolving the mixture, treating the mixture with a directional ultrasonic machine, and then subjecting the mixture to high-speed centrifugal separation and drying to a constant weight to obtain GLM-NPs / MOF liquid metal nanoparticles.
2. The method for preparing MOF-modified liquid metal nanoparticles according to claim 1, wherein: The UiO-66-NH2 powder is prepared by a hydrothermal method. The specific process is as follows: an excess amount of dimethylformamide, an organic solvent, is added to the inner wall of a reactor, and 2-aminoterephthalic acid and ZrCl4 are added in a molar ratio of 1:0.5 to 1:1, and the mixture is shaken evenly using an ultrasonic cleaner; the resulting mixture is placed in an autoclave and reacted at a high temperature of 373 to 403 K for 24 to 36 hours to obtain the powder.
3. The method for preparing MOF-modified liquid metal nanoparticles according to claim 1, wherein: The GaInSn liquid metal is prepared by the following method: 62-65% Ga, 22-25% In and 10-13% Sn by mass are mixed, placed in a tube furnace, completely melted under a pure argon atmosphere at 200°C, kept warm for 1-2 hours, and then cooled to room temperature.
4. The method for preparing MOF-modified liquid metal nanoparticles according to claim 3, wherein: The purity of Ga, In and Sn is 99.99%.
5. The method for preparing MOF-modified liquid metal nanoparticles according to claim 1, wherein: The conditions of the directional ultrasonic treatment are as follows: the ultrasonic power is 300-400W, the ultrasonic time is 30-60min, and the ultrasonic temperature is maintained at 15-30°C.
6. The method for preparing MOF-modified liquid metal nanoparticles according to claim 1, wherein: The centrifugal separation treatment conditions refer to a centrifugal speed of 5000-10000 rpm and a time of 3-10 min.
7. A MOF-modified liquid metal nanoparticle prepared by the method according to any one of claims 1 to 6.
8. The MOF-modified liquid metal nanoparticles according to claim 7, characterized in that: The particle size of the MOF-modified liquid metal nanoparticles is between 20 and 500 nm.
9. The MOF-modified liquid metal nanoparticles according to claim 7, characterized in that: When the MOF-modified liquid metal nanoparticles are used as additives for water-based lubricants, the addition amount is 0.3-0.9% by mass.