CN114539984B - Single-domain hydrated inorganic salt phase-change material and preparation method thereof - Google Patents
Single-domain hydrated inorganic salt phase-change material and preparation method thereof Download PDFInfo
- Publication number
- CN114539984B CN114539984B CN202210286634.2A CN202210286634A CN114539984B CN 114539984 B CN114539984 B CN 114539984B CN 202210286634 A CN202210286634 A CN 202210286634A CN 114539984 B CN114539984 B CN 114539984B
- Authority
- CN
- China
- Prior art keywords
- inorganic salt
- change material
- aerogel
- phase change
- domain
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K5/00—Heat-transfer, heat-exchange or heat-storage materials, e.g. refrigerants; Materials for the production of heat or cold by chemical reactions other than by combustion
- C09K5/02—Materials undergoing a change of physical state when used
- C09K5/06—Materials undergoing a change of physical state when used the change of state being from liquid to solid or vice versa
- C09K5/063—Materials absorbing or liberating heat during crystallisation; Heat storage materials
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E70/00—Other energy conversion or management systems reducing GHG emissions
- Y02E70/30—Systems combining energy storage with energy generation of non-fossil origin
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Combustion & Propulsion (AREA)
- Thermal Sciences (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
Abstract
The invention discloses a single-domain hydrated inorganic salt phase-change material and a preparation method thereof, and the single-domain hydrated inorganic salt phase-change material specifically comprises the following steps: applying a direct current electric field to the hydrocolloid to enable the nano-particles in the hydrocolloid to present uniform orientation, enabling the colloid with uniform orientation to flow through a liquid nitrogen pipeline to enable the nano-particles in the colloid to be solidified and shaped, and then freezing and drying to obtain the nano-particle aerogel with uniform orientation; carrying out plasma surface polarization and polyimide spraying on the nano-particle aerogel to form an anchoring layer on the surface of the aerogel; filling isotropic inorganic salt solution into the aerogel with the surface anchored with polyimide, defoaming in vacuum to obtain inorganic salt solution @ nano-particle aerogel, and then slowly crystallizing the inorganic salt solution under the combined induction of a temperature gradient field and mobile ultrasonic waves to obtain the monodomain hydrated inorganic salt phase-change material with uniform orientation. The homogeneous-orientation single-domain hydrated inorganic salt phase-change material prepared by the invention can improve the thermal conductivity and phase-change enthalpy value of the phase-change material.
Description
Technical Field
The invention relates to the technical field of phase-change materials, in particular to a single-domain hydrated inorganic salt phase-change material and a preparation method thereof.
Background
Phase change materials have received much attention for their ability to store and release latent heat for energy and thermal control purposes. The ability of phase change materials to store and release thermal energy has prompted researchers to apply them in a variety of fields, such as Photovoltaic (PV) panels, thermoelectric generators, architectural air conditioning, air and water heating systems, heat exchangers, desalination solar distillers, thermal management of textiles, electronics, and batteries, and food packaging. In terms of kinds, phase change materials are mainly classified into organic phase change materials and inorganic phase change materials. The hydrated inorganic salt in the inorganic phase-change material has the characteristics of low cost, wide source and the like, so that the hydrated inorganic salt has obvious advantages in the application process. However, the low thermal conductivity compared to metals in inorganic phase change materials limits their use to some extent. The thermal conductivity has been improved mainly by adding highly thermally conductive nanoparticles to hydrated inorganic salts. However, the addition of most of the heat-conducting fillers relatively reduces the enthalpy value of the inorganic hydrated salt phase change material, and simultaneously increases the use cost. There is therefore a need to develop a low cost process that increases both the thermal conductivity and enthalpy of hydrated inorganic salts.
Disclosure of Invention
The invention aims to provide a preparation method of a single-domain hydrated inorganic salt phase-change material, which can improve the heat conductivity and the enthalpy value of the phase-change material.
The invention also aims to provide the single-domain hydrated inorganic salt phase-change material prepared by the preparation method.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
in a first aspect, the invention provides a preparation method of a single-domain hydrated inorganic salt phase-change material, which comprises the following steps:
step 1: applying a DC electric field of 100V-10000V to the hydrocolloid in the DC electric field to ensure that the nano particles in the hydrocolloid are uniformly oriented;
step 2: enabling the colloid with uniform orientation in the step 1 to flow through a liquid nitrogen pipeline at a stable speed, solidifying and shaping the nano particles in the colloid, and then freezing and drying to obtain the nano particle aerogel with uniform orientation;
and step 3: carrying out surface polarization on the nanoparticle aerogel in the step 2 by adopting plasma to generate oxygen-containing groups, and carrying out surface spraying on the nanoparticle aerogel by adopting a polyimide solution to combine polyimide and oxygen atoms to form an anchoring layer on the surface of the nanoparticle aerogel;
and 4, step 4: heating and melting the hydrated inorganic salt crystals to obtain an isotropic inorganic salt solution, filling the inorganic salt solution into the nanoparticle aerogel with the polyimide anchored on the surface, and defoaming in vacuum to obtain an inorganic salt solution @ nanoparticle aerogel;
and 5: placing the inorganic salt solution @ nano particle aerogel in a certain temperature gradient field, slowly moving the inorganic salt solution @ nano particle aerogel from a high-temperature section of the temperature gradient field to a low-temperature section of the temperature gradient field by using a mobile ultrasonic instrument, wherein the temperature of the high-temperature section is 60-100 ℃, the temperature of the low-temperature section is 0-40 ℃, the temperature difference is 56-100 ℃, and the inorganic salt solution is slowly crystallized under the combined induction of the temperature gradient field and mobile ultrasonic waves to obtain the uniformly-oriented single-domain hydrated inorganic salt phase-change material.
Preferably, in step 1, the hydrocolloid is any one or a mixture of several of graphene oxide hydrocolloid, zirconium phosphate hydrocolloid and boron nitride hydrocolloid.
Preferably, in step 1, the mass concentration of the nanoparticles in the aqueous colloid is 0.1-10%.
Preferably, in the step 2, the inner diameter of the liquid nitrogen pipeline is 0.1 cm-10 cm, and the flowing time is 15-30 minutes.
Preferably, in the step 3, the power of the plasmatization surface polarization is 200W-8000W, and the processing time is 10-60 minutes.
Preferably, in the step 3, the mass concentration of the polyimide solution is 1-5%, and the spraying time is 1-5 minutes.
Preferably, in the step 4, the heating temperature is 30-100 ℃, the heating time is 15-30 minutes, and the defoaming time is 15-30 minutes.
Preferably, in step 4, the hydrated inorganic salt is at least one of lithium perchlorate trihydrate, potassium fluoride trihydrate, calcium chloride hexahydrate, lithium nitrate trihydrate, sodium sulfate decahydrate, disodium hydrogen phosphate dodecahydrate, sodium thiosulfate pentahydrate, and sodium acetate trihydrate.
Preferably, in step 5, the distance between the high temperature section and the low temperature section in the temperature gradient field is 10cm to 50 cm.
Preferably, in step 5, the frequency of the ultrasonic wave is 100 to 1000 Hz.
Preferably, in step 5, the moving speed of the ultrasonic waves is 0.001ms -1 ～0.01ms -1 。
On the other hand, the invention also provides the monodomain hydrated inorganic salt phase-change material prepared by the preparation method.
Compared with the prior art, the invention has the following beneficial effects:
1. the invention adopts a direct current electric field to induce the nano particles to form uniform orientation, and is a method for simply and efficiently inducing the orientation of the nano particles.
2. The surface polarization and polyimide modification are combined to form the polyimide anchoring layer, so that the inorganic hydrated salt on the surface layer can be induced to attach to the nanoparticle aerogel for orientation.
3. The inorganic salt solution slowly crystallizes under the combined induction of the temperature gradient field and the mobile ultrasonic wave to obtain the monodomain hydrated inorganic salt phase-change material with uniform orientation. The homogeneous-orientation single-domain hydrated inorganic salt phase change material prepared by the invention can improve the thermal conductivity of the phase change material and increase the phase change enthalpy value of the phase change material because the defect is avoided.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive exercise.
FIG. 1 is a flow chart of preparing a single-domain hydrated inorganic salt phase-change material according to an embodiment of the present invention.
FIG. 2 is an X-ray diffraction spectrum of the monodomain phase change material obtained in example 1.
FIG. 3 is a differential scanning calorimetry curve of the monodomain phase change material obtained in example 1.
Fig. 4 is a polarization micrograph of the monodomain phase change material obtained in example 1.
FIG. 5 is a scanning electron microscope image of the single domain phase change material obtained in example 1.
FIG. 6 is an X-ray diffraction spectrum of the monodomain phase change material obtained in example 2.
FIG. 7 is a differential scanning calorimetry curve of the monodomain phase change material obtained in example 2.
Fig. 8 is a polarization micrograph of the monodomain phase change material obtained in example 2.
FIG. 9 is a scanning electron microscope image of the single domain phase change material obtained in example 2.
FIG. 10 is an X-ray diffraction spectrum of the monodomain phase change material obtained in example 3.
FIG. 11 is a differential scanning calorimetry curve of the monodomain phase change material obtained in example 3.
Fig. 12 is a polarization micrograph of the monodomain phase change material obtained in example 3.
FIG. 13 is a scanning electron microscope image of the single domain phase change material obtained in example 3.
FIG. 14 is an X-ray diffraction spectrum of the monodomain phase change material obtained in example 4.
FIG. 15 is a differential scanning calorimetry curve of the monodomain phase change material obtained in example 4.
Fig. 16 is a polarization micrograph of the monodomain phase change material obtained in example 4.
FIG. 17 is a scanning electron microscope image of the single domain phase change material obtained in example 4.
FIG. 18 is an X-ray diffraction spectrum of the monodomain phase change material obtained in example 5.
FIG. 19 is a differential scanning calorimetry curve of the monodomain phase change material obtained in example 5.
FIG. 20 is a polarization micrograph of the monodomain phase change material obtained in example 5.
Fig. 21 is a scanning electron microscope image of the monodomain phase change material obtained in example 5.
FIG. 22 is an X-ray diffraction spectrum of the monodomain phase change material obtained in example 6.
FIG. 23 is a differential scanning calorimetry curve of the monodomain phase change material obtained in example 6.
FIG. 24 is a polarization micrograph of the monodomain phase change material obtained in example 6.
FIG. 25 is a SEM image of the single domain phase change material obtained in example 6.
FIG. 26 is an X-ray diffraction pattern of the monodomain phase change material obtained in example 7.
FIG. 27 is a differential scanning calorimetry curve of the monodomain phase change material obtained in example 7.
Fig. 28 is a polarization micrograph of the monodomain phase change material obtained in example 7.
FIG. 29 is a SEM image of the single domain phase change material obtained in example 7.
Detailed Description
In order to make the objects, features and advantages of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention will be clearly and completely described below, and it should be apparent that the embodiments described below are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
Step 1: applying a 100V direct current electric field to the graphene oxide hydrocolloid in the direct current electric field to enable the nanoparticles in the water-soluble colloid to present uniform orientation; the mass concentration of graphene oxide in the hydrocolloid is 0.1%.
And 2, step: allowing the uniformly oriented graphene oxide colloid in the step 1 to flow through a liquid nitrogen pipeline, solidifying and shaping the graphene oxide in the colloid, and freeze-drying to obtain the uniformly oriented graphene oxide aerogel; wherein the inner diameter of the liquid nitrogen pipeline is 0.1cm, and the flowing time of the colloid is 15 minutes;
and step 3: carrying out surface polarization on the graphene oxide aerogel by adopting plasma to generate oxygen-containing groups, wherein the power of the plasma surface polarization is 200W, and the processing time is 10 minutes; and then, spraying the surface of the nano-particle aerogel by adopting a polyimide solution with the mass concentration of 1%, wherein the spraying time is 1 minute, so that the polyimide is combined with oxygen atoms to form an anchoring layer on the surface of the nano-particle aerogel.
And 4, step 4: heating lithium perchlorate trihydrate at 30 ℃ for 15 minutes, melting to obtain an isotropic lithium perchlorate solution, filling the lithium perchlorate solution into the nanoparticle aerogel with polyimide anchored on the surface, and defoaming in a vacuum environment for 15 minutes to obtain the lithium perchlorate trihydrate solution @ graphene oxide aerogel.
Step (ii) of5: placing the lithium perchlorate trihydrate solution @ graphene oxide aerogel in a certain temperature gradient field, wherein the temperature of a high-temperature section in the temperature gradient field is 60 ℃, the temperature of a low-temperature section in the temperature gradient field is 0 ℃, and the distance between the high-temperature section and the low-temperature section in the temperature gradient field is 10 cm. The mobile ultrasonic instrument is adopted to slowly move from the high-temperature section of the temperature gradient field to the low-temperature section of the temperature gradient field through the lithium perchlorate trihydrate solution @ graphene oxide aerogel, the frequency of the ultrasonic wave is 100Hz, and the moving speed of the ultrasonic wave is 0.001ms -1 . The lithium perchlorate trihydrate solution is slowly crystallized under the combined induction of a temperature gradient field and mobile ultrasonic waves to obtain the monodomain hydrated inorganic salt phase-change material with uniform orientation.
FIG. 2 is an X-ray diffraction spectrum of the monodomain phase change material obtained in example 1. From the spectrogram, the single-domain phase change material has high crystallinity and few defects.
FIG. 3 is a differential scanning calorimetry curve of the single-domain phase change material obtained in example 1, from which it can be seen that the melting peak of the single-domain phase change material is very single, which proves that the crystal is single and the crystal purity is high.
FIG. 4 is a polarization micrograph of the monodomain phase change material obtained in example 1, which sample after crystallization has a pronounced crystal structure and uniform birefringence.
Fig. 5 is a scanning electron microscope image of the single domain phase change material obtained in example 1, and it can be seen from the image that the structure of the single domain phase change material is dense and the orientation is uniform.
Example 2
Step 1: and applying 10000V direct current electric field to the zirconium phosphate aqueous colloid in the direct current electric field to ensure that the nano particles in the water-soluble colloid present uniform orientation. The mass concentration of zirconium phosphate in the hydrocolloid was 10%.
And 2, step: allowing the uniformly oriented zirconium phosphate colloid in the step 1 to flow through a liquid nitrogen pipeline, solidifying and shaping zirconium phosphate in the colloid, and freeze-drying to obtain uniformly oriented zirconium phosphate aerogel; wherein the inner diameter of the liquid nitrogen pipeline is 10cm, and the flowing time is 30 minutes.
And step 3: carrying out surface polarization on zirconium phosphate aerogel by adopting plasma to generate oxygen-containing groups, wherein the power of the plasma surface polarization is 8000W, and the treatment time is 60 minutes; and then, spraying the polyimide solution with the mass concentration of 5% on the surface of the substrate for 5 minutes. And combining the polyimide with oxygen atoms to form an anchoring layer on the surface of the nano-particle aerogel.
And 4, step 4: heating the potassium fluoride trihydrate at 100 ℃ for 30 minutes, melting to obtain an isotropic potassium fluoride solution, filling the potassium fluoride solution into the nanoparticle aerogel with the polyimide anchored on the surface, and defoaming in a vacuum environment for 30 minutes to obtain the potassium fluoride trihydrate solution @ zirconium phosphate aerogel.
And 5: the potassium fluoride trihydrate solution @ zirconium phosphate aerogel is placed in a certain temperature gradient field, the temperature of a high-temperature section in the temperature gradient field is 100 ℃, the temperature of a low-temperature section in the temperature gradient field is 0 ℃, and the distance between the high-temperature section and the low-temperature section in the temperature gradient field is 50 cm. The ultrasonic wave is generated by slowly moving the lithium perchlorate trihydrate solution @ graphene oxide aerogel from the high-temperature section of the temperature gradient field to the low-temperature section of the temperature gradient field by a mobile ultrasonic instrument, wherein the frequency of the ultrasonic wave is 1000Hz, and the moving speed of the ultrasonic wave is 0.01ms -1 . The potassium fluoride solution is slowly crystallized under the combined induction of a temperature gradient field and mobile ultrasonic waves to obtain the monodomain hydrated inorganic salt phase-change material with uniform orientation.
FIG. 6 is an X-ray diffraction spectrum of the monodomain phase change material obtained in example 2. From the spectrogram, the single-domain phase change material has high crystallinity and few defects.
Fig. 7 is a differential scanning calorimetry curve of the monodomain phase change material obtained in example 2, and it can be seen from the curve that the melting peak of the monodomain phase change material is very single, which proves that the crystal is single and the crystal purity is high.
FIG. 8 is a polarization micrograph of the monodomain phase change material obtained in example 2, which sample after crystallization has a pronounced crystal structure and uniform birefringence.
Fig. 9 is a scanning electron microscope image of the monodomain phase change material obtained in example 2, and it can be seen from the image that the structure of the monodomain phase change material is dense and the orientation is uniform.
Example 3
Step 1: and applying a 5000V direct current electric field to the boron nitride hydrocolloid in the direct current electric field to enable the nano particles in the water-soluble colloid to present uniform orientation. The mass concentration of boron nitride in the hydrocolloid was 5%.
Step 2: and (2) enabling the uniformly-oriented boron nitride colloid in the step (1) to flow through a liquid nitrogen pipeline, solidifying and shaping the boron nitride in the colloid, and then carrying out freeze drying to obtain the uniformly-oriented boron nitride aerogel, wherein the inner diameter of the liquid nitrogen pipeline is 5cm, and the flowing time is 20 minutes.
And step 3: the boron nitride aerogel is subjected to surface polarization by adopting plasma to generate oxygen-containing groups, the power of the plasma surface polarization is 4000W, and the treatment time is 30 minutes. And then the surface of the film is sprayed by adopting a polyimide solution with the mass concentration of 3 percent, and the spraying time is 3 minutes. And combining the polyimide with oxygen atoms to form an anchoring layer on the surface of the nano-particle aerogel.
And 4, step 4: heating calcium chloride hexahydrate at 60 ℃ for 20 minutes, melting to obtain an isotropic calcium chloride solution, filling the calcium chloride solution into the nanoparticle aerogel with the polyimide anchored on the surface, and defoaming in a vacuum environment for 20 minutes to obtain the calcium chloride hexahydrate @ boron nitride aerogel.
And 5: the calcium chloride hexahydrate and boron nitride aerogel is placed in a certain temperature gradient field, the temperature of a high-temperature section in the temperature gradient field is 80 ℃, the temperature of a low-temperature section in the temperature gradient field is 10 ℃, and the distance between the high-temperature section and the low-temperature section in the temperature gradient field is 30 cm. Slowly passing through calcium chloride hexahydrate @ boron nitride aerogel from the high-temperature section of the temperature gradient field to the low-temperature section of the temperature gradient field by adopting a mobile ultrasonic instrument, wherein the frequency of ultrasonic waves is 500Hz, and the moving speed of the ultrasonic waves is 0.005ms -1 . The calcium chloride solution is slowly crystallized under the combined induction of a temperature gradient field and mobile ultrasonic waves to obtain the monodomain hydrated inorganic salt phase-change material with uniform orientation.
FIG. 10 is an X-ray diffraction spectrum of the monodomain phase change material obtained in example 3. From the spectrogram, the single-domain phase change material has high crystallinity and few defects.
Fig. 11 is a differential scanning calorimetry curve of the monodomain phase change material obtained in example 3, and it can be seen from the curve that the melting peak of the monodomain phase change material is very single, which proves that the crystal is single and the crystal purity is high.
FIG. 12 is a polarization micrograph of the monodomain phase change material obtained in example 3, which sample has a pronounced crystal structure and uniform birefringence after crystallization.
FIG. 13 is a scanning electron microscope image of the single domain phase change material obtained in example 3, and it can be seen that the structure of the single domain phase change material is dense and the orientation is uniform.
Example 4
Step 1: 7000V direct current electric field is applied to the boron nitride aqueous colloid in the direct current electric field, so that the nano particles in the aqueous colloid are in uniform orientation. The mass concentration of boron nitride in the hydrocolloid was 7%.
Step 2: and (2) allowing the uniformly-oriented boron nitride colloid in the step (1) to flow through a liquid nitrogen pipeline, solidifying and shaping the boron nitride in the colloid, and freeze-drying to obtain the uniformly-oriented boron nitride aerogel, wherein the inner diameter of the liquid nitrogen pipeline is 2cm, and the flowing time is 15 minutes.
And step 3: the boron nitride aerogel is subjected to surface polarization by adopting plasma to generate oxygen-containing groups, the power of the plasma surface polarization is 2000W, and the treatment time is 20 minutes. And then, the surface of the polyimide is sprayed by adopting a polyimide solution with the mass concentration of 2%, wherein the spraying time is 4 minutes. And combining the polyimide with oxygen atoms to form an anchoring layer on the surface of the nano-particle aerogel.
And 4, step 4: heating lithium nitrate trihydrate at 90 ℃ for 30 minutes, melting to obtain an isotropic lithium nitrate solution, filling the lithium nitrate solution into the nanoparticle aerogel with polyimide anchored on the surface, and defoaming in a vacuum environment for 20 minutes to obtain the lithium nitrate trihydrate solution @ boron nitride aerogel.
And 5: placing lithium nitrate trihydrate solution @ boron nitride aerogel in a certain temperature gradient field, wherein the temperature gradient field isThe temperature of the high temperature section in the field is 90 ℃, the temperature of the low temperature section is 15 ℃, and the distance between the high temperature section and the low temperature section in the temperature gradient field is 20 cm. Slowly passing lithium nitrate trihydrate solution @ boron nitride aerogel from the high-temperature section of the temperature gradient field to the low-temperature section of the temperature gradient field by adopting a mobile ultrasonic instrument, wherein the frequency of ultrasonic waves is 800Hz, and the moving speed of the ultrasonic waves is 0.004ms -1 . Slowly crystallizing the lithium nitrate solution under the combined induction of a temperature gradient field and mobile ultrasonic waves to obtain the monodomain hydrated inorganic salt phase-change material with uniform orientation.
FIG. 14 is an X-ray diffraction spectrum of the monodomain phase change material obtained in example 4. From the spectrogram, the single-domain phase change material has high crystallinity and few defects.
FIG. 15 is a differential scanning calorimetry curve of the single-domain phase change material obtained in example 4, from which it can be seen that the melting peak of the single-domain phase change material is very single, which proves that the crystal is single and the crystal purity is high.
FIG. 16 is a polarization micrograph of the monodomain phase change material obtained in example 4, which sample has a pronounced crystal structure and uniform birefringence after crystallization.
FIG. 17 is a scanning electron microscope image of the single domain phase change material obtained in example 4, and it can be seen that the structure of the single domain phase change material is dense and the orientation is uniform.
Example 5
Step 1: and applying a 1000V direct-current electric field to the graphene oxide hydrocolloid in the direct-current electric field to enable the nanoparticles in the water-soluble colloid to present uniform orientation. The mass concentration of graphene oxide in the hydrocolloid was 2%.
And 2, step: and (3) enabling the uniformly-oriented graphene oxide colloid in the step (1) to flow through a liquid nitrogen pipeline, solidifying and shaping the graphene oxide in the colloid, and then carrying out freeze drying to obtain the uniformly-oriented graphene oxide aerogel, wherein the inner diameter of the liquid nitrogen pipeline is 8cm, and the flow time is 20 minutes.
And step 3: surface polarization is carried out on the graphene oxide aerogel by adopting plasma to generate oxygen-containing groups, the power of the plasma surface polarization is 3000W, and the treatment time is 22 minutes. And then, the surface of the polyimide is sprayed by adopting a polyimide solution with the mass concentration of 4%, wherein the spraying time is 3 minutes. And combining the polyimide with oxygen atoms to form an anchoring layer on the surface of the nano-particle aerogel.
And 4, step 4: heating sodium sulfate decahydrate at 73 ℃ for 24 minutes, melting to obtain an isotropic sodium sulfate solution, filling the sodium sulfate solution into the nanoparticle aerogel with the polyimide anchored on the surface, and defoaming in a vacuum environment for 18 minutes to obtain the sodium sulfate decahydrate solution @ graphene oxide aerogel.
And 5: the sodium sulfate decahydrate solution @ graphene oxide aerogel is placed in a certain temperature gradient field, the temperature of a high-temperature section in the temperature gradient field is 77 ℃, the temperature of a low-temperature section in the temperature gradient field is 21 ℃, and the distance between the high-temperature section and the low-temperature section in the temperature gradient field is 23 cm. Slowly passing the sodium sulfate decahydrate solution @ graphene oxide aerogel from the high-temperature section of the temperature gradient field to the low-temperature section of the temperature gradient field by using a mobile ultrasonic instrument, wherein the frequency of the ultrasonic wave is 500Hz, and the moving speed of the ultrasonic wave is 0.003ms -1 . Slowly crystallizing the sodium sulfate solution under the combined induction of a temperature gradient field and mobile ultrasonic waves to obtain the monodomain hydration inorganic salt phase-change material with uniform orientation.
FIG. 18 is an X-ray diffraction spectrum of the monodomain phase change material obtained in example 5. From the spectrogram, the single-domain phase change material has high crystallinity and few defects.
FIG. 19 is a differential scanning calorimetry curve of the single-domain phase change material obtained in example 5, from which it can be seen that the melting peak of the single-domain phase change material is very single, which proves that the crystal is single and the crystal purity is high.
FIG. 20 is a polarization micrograph of the monodomain phase change material obtained in example 5, which sample after crystallization has a pronounced crystal structure and uniform birefringence.
FIG. 21 is a scanning electron microscope image of the single domain phase change material obtained in example 5, and it can be seen that the structure of the single domain phase change material is dense and the orientation is uniform.
Example 6
Step 1: and applying a 3400V direct current electric field to the graphene oxide hydrocolloid in the direct current electric field to enable the nanoparticles in the water-soluble colloid to present uniform orientation. The mass concentration of graphene oxide in the hydrocolloid was 4.1%.
Step 2: and (3) enabling the uniformly oriented graphene oxide colloid in the step (1) to flow through a liquid nitrogen pipeline, solidifying and shaping the graphene oxide in the colloid, and then carrying out freeze drying to obtain the uniformly oriented graphene oxide aerogel. Wherein the inner diameter of the liquid nitrogen pipe is 7.5cm, and the flowing time is 19 minutes.
And step 3: surface polarization is carried out on the graphene oxide aerogel by adopting plasma to generate oxygen-containing groups, the power of the plasma surface polarization is 6100W, and the processing time is 22 minutes. And then the polyimide solution with the mass concentration of 2.1% is adopted to carry out surface spraying on the polyimide solution, and the spraying time is 3 minutes. And combining the polyimide with oxygen atoms to form an anchoring layer on the surface of the nano-particle aerogel.
And 4, step 4: heating disodium hydrogen phosphate dodecahydrate at 83 ℃ for 29 minutes, melting to obtain an isotropic disodium hydrogen phosphate solution, filling the disodium hydrogen phosphate solution into the nanoparticle aerogel with polyimide anchored on the surface, and defoaming in a vacuum environment for 16 minutes to obtain the disodium hydrogen phosphate dodecahydrate solution @ graphene oxide aerogel.
And 5: the disodium hydrogen phosphate dodecahydrate solution @ graphene oxide aerogel is placed in a certain temperature gradient field, the temperature of a high-temperature section in the temperature gradient field is 82 ℃, the temperature of a low-temperature section in the temperature gradient field is 8 ℃, and the distance between the high-temperature section and the low-temperature section in the temperature gradient field is 21 cm. Slowly passing through sodium sulfate decahydrate solution @ graphene oxide aerogel from the high-temperature section of the temperature gradient field to the low-temperature section of the temperature gradient field by adopting a mobile ultrasonic instrument, wherein the frequency of ultrasonic waves is 750Hz, and the moving speed of the ultrasonic waves is 0.0025ms -1 . The disodium hydrogen phosphate solution is slowly crystallized under the combined induction of a temperature gradient field and mobile ultrasonic waves to obtain the monodomain hydrated inorganic salt phase-change material with uniform orientation.
FIG. 22 is an X-ray diffraction spectrum of the monodomain phase change material obtained in example 6. From the spectrogram, the single-domain phase change material has high crystallinity and few defects.
FIG. 23 is a differential scanning calorimetry curve of the single-domain phase change material obtained in example 6, from which it can be seen that the melting peak of the single-domain phase change material is single, which proves that the crystal is single and the crystal purity is high.
FIG. 24 is a polarization micrograph of the monodomain phase change material obtained in example 6, which sample has a pronounced crystal structure and uniform birefringence after crystallization.
FIG. 25 is a scanning electron microscope image of the single domain phase change material obtained in example 6, and it can be seen that the structure of the single domain phase change material is dense and the orientation is uniform.
Example 7
Step 1: 8000V of direct current electric field is applied to the zirconium phosphate water-based colloid in the direct current electric field, so that the nano particles in the water-soluble colloid present uniform orientation. The mass concentration of zirconium phosphate in the hydrocolloid was 6%.
Step 2: and (3) allowing the uniformly oriented zirconium phosphate colloid in the step (1) to flow through a liquid nitrogen pipeline, solidifying and shaping zirconium phosphate in the colloid, and freeze-drying to obtain the uniformly oriented zirconium phosphate aerogel. Wherein the inner diameter of the liquid nitrogen pipeline is 8cm, and the flowing time is 27 minutes.
And step 3: the zirconium phosphate aerogel is subjected to surface polarization by adopting plasma to generate oxygen-containing groups, the power of the plasma surface polarization is 5000W, and the treatment time is 40 minutes. And then, the surface of the polyimide is sprayed by adopting a polyimide solution with the mass concentration of 2%, wherein the spraying time is 4 minutes. And combining the polyimide with oxygen atoms to form an anchoring layer on the surface of the nano-particle aerogel.
And 4, step 4: heating sodium thiosulfate pentahydrate at 80 ℃ for 20 minutes, melting to obtain an isotropic sodium thiosulfate solution, filling the sodium thiosulfate solution into the nanoparticle aerogel with polyimide anchored on the surface, and defoaming in a vacuum environment for 30 minutes to obtain the sodium thiosulfate pentahydrate solution @ zirconium phosphate aerogel.
And 5: sodium thiosulfate pentahydrate solution @ phosphoric acidThe zirconium aerogel is placed in a certain temperature gradient field, the temperature of a high-temperature section in the temperature gradient field is 95 ℃, the temperature of a low-temperature section in the temperature gradient field is 3 ℃, and the distance between the high-temperature section and the low-temperature section in the temperature gradient field is 30 cm. Slowly passing through sodium thiosulfate pentahydrate solution @ zirconium phosphate aerogel from the high-temperature section of the temperature gradient field to the low-temperature section of the temperature gradient field by adopting a mobile ultrasonic instrument, wherein the frequency of ultrasonic waves is 600Hz, and the moving speed of the ultrasonic waves is 0.002ms -1 . Slowly crystallizing the sodium thiosulfate solution under the combined induction of a temperature gradient field and mobile ultrasonic waves to obtain the monodomain hydration inorganic salt phase-change material with uniform orientation.
FIG. 26 is an X-ray diffraction pattern of the monodomain phase change material obtained in example 7. From the spectrogram, the single-domain phase change material has high crystallinity and few defects.
Fig. 27 is a differential scanning calorimetry curve of the monodomain phase change material obtained in example 7, from which it can be seen that the melting peak of the monodomain phase change material is very single, demonstrating that the crystal is single and the crystal purity is high.
FIG. 28 is a polarization micrograph of the monodomain phase change material obtained in example 7, which sample after crystallization has a pronounced crystal structure and uniform birefringence.
FIG. 29 is a scanning electron microscope image of the single domain phase change material obtained in example 7, and it can be seen that the structure of the single domain phase change material is dense and the orientation is uniform.
Thermal conductivity and enthalpy of phase change of the single domain phase change material in the example of table 1
As can be seen from Table 1, the thermal conductivity of the monodomain inorganic phase change material in the examples is obviously more than 0.7Wm -1 K -1 The thermal conductivity of the conventional inorganic phase change material is generally less than 0.6Wm -1 K -1 (ii) a In the embodiment, the phase change enthalpy value of the single-domain inorganic phase change material is obviously more than 260Jg -1 The phase change enthalpy value of the conventional inorganic phase change material is generally less than 260Jg -1 . The heat conductivity and the phase change enthalpy value of the single-domain inorganic phase change material prepared by the invention are both greatly improved, so that the application condition of the inorganic hydrated salt phase change material in the actual life is greatly improved.
Claims (11)
1. A preparation method of a single-domain hydrated inorganic salt phase-change material is characterized by comprising the following steps:
step 1: applying a 100V-10000V direct current electric field to the hydrocolloid in the direct current electric field to enable the nano particles in the hydrocolloid to present uniform orientation; the aqueous colloid is any one of graphene oxide aqueous colloid, zirconium phosphate aqueous colloid and boron nitride aqueous colloid;
step 2: enabling the colloid with the uniform orientation in the step 1 to flow through a liquid nitrogen pipeline at a stable speed, solidifying and sizing the nano particles in the colloid, and then freezing and drying to obtain the nano particle aerogel with the uniform orientation;
and step 3: carrying out surface polarization on the nanoparticle aerogel in the step 2 by adopting plasma to generate oxygen-containing groups, and then carrying out surface spraying on the nanoparticle aerogel by adopting a polyimide solution to combine polyimide and oxygen atoms to form an anchoring layer on the surface of the nanoparticle aerogel;
and 4, step 4: heating and melting the hydrated inorganic salt crystals to obtain an isotropic inorganic salt solution, filling the inorganic salt solution into the nanoparticle aerogel with the polyimide anchored on the surface, and defoaming in vacuum to obtain an inorganic salt solution @ nanoparticle aerogel;
and 5: placing the inorganic salt solution @ nano particle aerogel in a certain temperature gradient field, and slowly moving the inorganic salt solution @ nano particle aerogel from the high-temperature section of the temperature gradient field to the low-temperature section of the temperature gradient field by using a mobile ultrasonic instrument until the temperature of the high-temperature section is 60 DEG C o C~100 o C, the temperature of the low temperature section is 0 o C~40 o C, temperature difference 56 o C~100 o And C, slowly crystallizing the inorganic salt solution under the combined induction of the temperature gradient field and the mobile ultrasonic wave to obtain the monodomain hydrated inorganic salt phase-change material with uniform orientation.
2. The method for preparing the monodomain hydrated inorganic salt phase change material as claimed in claim 1, wherein in the step 1, the mass concentration of the nano particles in the aqueous colloid is 0.1-10%.
3. The method for preparing a single domain hydrated inorganic salt phase change material as claimed in claim 1, wherein in the step 2, the inner diameter of the liquid nitrogen pipeline is 0.1 cm-10 cm, and the flowing time is 15-30 minutes.
4. The method for preparing a single-domain hydrated inorganic salt phase-change material as claimed in claim 1, wherein in the step 3, the power of the plasmatized surface polarization is 200W-8000W, and the treatment time is 10-60 minutes.
5. The preparation method of the single-domain hydrated inorganic salt phase-change material as claimed in claim 1, wherein in the step 3, the mass concentration of the polyimide solution is 1-5%, and the spraying time is 1-5 minutes.
6. The method for preparing a monodomain hydrating inorganic salt phase change material of claim 1, wherein in the step 4, the heating temperature is 30 ℃ o C~100 o C, heating for 15-30 minutes, and defoaming for 15-30 minutes.
7. The method of claim 1, wherein in the step 4, the hydrated inorganic salt is at least one of lithium perchlorate trihydrate, potassium fluoride trihydrate, calcium chloride hexahydrate, lithium nitrate trihydrate, sodium sulfate decahydrate, disodium hydrogen phosphate dodecahydrate, sodium thiosulfate pentahydrate, and sodium acetate trihydrate.
8. The preparation method of the monodomain hydrated inorganic salt phase change material as claimed in claim 1, wherein in the step 5, the distance between a high-temperature section and a low-temperature section in the temperature gradient field is 10 cm-50 cm.
9. The preparation method of the single-domain hydrated inorganic salt phase-change material as claimed in claim 1, wherein in the step 5, the frequency of the ultrasonic wave is 100 Hz-1000 Hz.
10. The method as claimed in claim 1, wherein the moving speed of the ultrasonic wave in step 5 is 0.001ms -1 ~0.01ms -1 。
11. The phase change material of a monodomain hydrated inorganic salt obtained by the production method as set forth in any one of claims 1 to 10.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210286634.2A CN114539984B (en) | 2022-03-22 | 2022-03-22 | Single-domain hydrated inorganic salt phase-change material and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210286634.2A CN114539984B (en) | 2022-03-22 | 2022-03-22 | Single-domain hydrated inorganic salt phase-change material and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114539984A CN114539984A (en) | 2022-05-27 |
| CN114539984B true CN114539984B (en) | 2022-08-26 |
Family
ID=81666058
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210286634.2A Active CN114539984B (en) | 2022-03-22 | 2022-03-22 | Single-domain hydrated inorganic salt phase-change material and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114539984B (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110628155A (en) * | 2019-09-27 | 2019-12-31 | 中国科学院深圳先进技术研究院 | MXene/metal composite aerogel, preparation method and application thereof, and thermal interface material comprising MXene/metal composite aerogel |
| CN110951114A (en) * | 2019-11-24 | 2020-04-03 | 上海大学 | Three-dimensional carbon fiber graphene aerogel high-molecular composite material and preparation method thereof |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105110313B (en) * | 2015-07-25 | 2017-12-01 | 复旦大学 | A kind of polyimide-based compound carbon aerogels and preparation method thereof |
| CN107365425B (en) * | 2016-05-12 | 2020-11-06 | 复旦大学 | Preparation method and product of polyimide-based composite aerogel |
| CN110804420B (en) * | 2019-10-09 | 2020-11-20 | 北京化工大学 | Phase-change composite material based on high-thermal-conductivity anisotropic graphene framework and preparation method thereof |
| CN111841457B (en) * | 2020-08-20 | 2022-06-24 | 广东工业大学 | Metal ion/zirconium phosphate aerogel, preparation method thereof and composite phase change energy storage material |
| CN112852386B (en) * | 2021-01-25 | 2022-03-29 | 武汉科技大学 | High-orientation layered graphene aerogel phase-change composite material and preparation method thereof |
-
2022
- 2022-03-22 CN CN202210286634.2A patent/CN114539984B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110628155A (en) * | 2019-09-27 | 2019-12-31 | 中国科学院深圳先进技术研究院 | MXene/metal composite aerogel, preparation method and application thereof, and thermal interface material comprising MXene/metal composite aerogel |
| CN110951114A (en) * | 2019-11-24 | 2020-04-03 | 上海大学 | Three-dimensional carbon fiber graphene aerogel high-molecular composite material and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114539984A (en) | 2022-05-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Mo et al. | Ti3C2Tx@ polyvinyl alcohol foam-supported phase change materials with simultaneous enhanced thermal conductivity and solar-thermal conversion performance | |
| Xiao et al. | Solar thermal energy storage based on sodium acetate trihydrate phase change hydrogels with excellent light-to-thermal conversion performance | |
| CN104743551B (en) | A kind of preparation method of redox graphene heat conduction thin film | |
| Han et al. | Synthesis of indium tin oxide (ITO) and fluorine-doped tin oxide (FTO) nano-powder by sol–gel combustion hybrid method | |
| CN101723436B (en) | Self-assembly zinc oxide hollow sphere and preparation method thereof | |
| Wada et al. | Fabrication of bismuth telluride nanoplates via solvothermal synthesis using different alkalis and nanoplate thin films by printing method | |
| CN109181654B (en) | Graphene-based composite heat-conducting film and preparation method and application thereof | |
| CN105821391B (en) | A kind of controllable fast preparation method of vertical substrate grown tungsten selenide nano sheet film materials | |
| Nithiyanantham et al. | Effect of silica nanoparticle size on the stability and thermophysical properties of molten salts based nanofluids for thermal energy storage applications at concentrated solar power plants | |
| CN101244812A (en) | Method for manufacturing flying saucer shaped nano-hexagonal boron nitride powder | |
| CN102709351A (en) | Cuprous sulfide film with preferred orientation growth | |
| Wang et al. | Hydrothermal synthesis of phosphate-mediated ZnO nanosheets | |
| Ma et al. | Enhanced thermal energy storage performance of hydrous salt phase change material via defective graphene | |
| CN114539984B (en) | Single-domain hydrated inorganic salt phase-change material and preparation method thereof | |
| Cheng et al. | Thermal energy storage properties of carbon nanotubes/sodium acetate trihydrate/sodium monohydrogen phosphate dodecahydrate composite phase-change materials as promising heat storage materials | |
| Kim et al. | Mg (OH) 2 nano-sheet decorated MgO micro-beams by electron beam irradiation for thermochemical heat storage | |
| CN112661992B (en) | Preparation method of high-thermal-conductivity polymer composite film with forest tree distributed structure | |
| CN110105871B (en) | Preparation method of super-hydrophobic photo-thermal ice-suppressing coating by taking iron-copper-manganese metal salt and nano silicon dioxide as raw materials | |
| Jo et al. | Anomalous rheological behavior of complex fluids (nanofluids) | |
| Cheng et al. | Development of flexible piezoelectric nanogenerator: Toward all wet chemical method | |
| Xu et al. | Robust photothermal anti-icing/deicing via flexible CMDSP carbon nanotube films | |
| CN110964219A (en) | Nano cellulose membrane with high thermal conductivity and preparation method thereof | |
| Hayat et al. | Enhancing thermal energy storage in buildings with novel functionalised MWCNTs-enhanced phase change materials: Towards efficient and stable solutions | |
| CN113122809B (en) | Method for controllably preparing amorphous flexible Bi-Te-Se film by adopting vacuum evaporation coating | |
| CN103964426A (en) | Method for preparing graphene |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |