CN109231158B - Nano packaging structure enabling dynamics of active material to be controllable and preparation method - Google Patents
Nano packaging structure enabling dynamics of active material to be controllable and preparation method Download PDFInfo
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Abstract
The invention discloses a nano packaging structure and a preparation method for enabling active material dynamics to be controllable, which mainly take a nano packaging technology of graphene to active alkali metal, hydride thereof and aluminum hydride to regulate and control the hydrolysis reaction dynamics process of the graphene as an example. The method is simple and feasible, has low cost and is suitable for industrial production.
Description
Technical Field
The invention belongs to the technical field of new energy materials and preparation thereof, and particularly relates to a nano packaging structure enabling dynamics of an active material to be controllable and a preparation method thereof.
Background
Active materials such as alkali metals and hydrides thereof, aluminum hydride and the like are very easy to oxidize and deliquesce, so that the storage is difficult, and meanwhile, the active materials undergo an explosive reaction when meeting water, thereby greatly limiting the practical application of the active materials. At present, active materials (such as metals such as lithium, potassium, sodium and the like, hydrides thereof, aluminum hydrides thereof and the like) are sealed in light mineral oil for storage, but the active materials need to be taken out of the oil in a glove box and oil stains need to be wiped off in use, and the use and operation requirements are high. In the prior art, lithium hydride, light mineral oil and a dispersant are prepared into slurry for packaging and storage; in the prior art, calcium hydride and epoxy resin are mixed, stirred, cured and packaged, and then the outer surface is further packaged by adopting an aluminum layer. This method is effective in inhibiting uncontrolled reactions of the active material therein, but has a problem of low mass ratio of the active material. Sodium hydride is also packaged by a resin film coating or plastic balls, but the balls need to be opened one by one in a vehicle, the technical requirements are high when the sodium hydride is used, the packaging method also has low effective mass ratio, and the outer packaging material needs to be peeled off when the sodium hydride is used, and the sodium hydride is stored like an oil seal type. The macro-packaging method generally has the problems of low effective mass ratio, need to remove the packaging material in use, need to complete operation in an inert atmosphere environment and the like. Due to the characteristics of the nanometer material such as nanometer size effect, high specific surface area and the like, the nanometer packaging can be used for carrying out surface modification on the material or synthesizing a new material, and has wide application prospects in the aspects of sintering, catalysis, sensing and the like of magnetic materials, electronic materials, optical materials and high-strength and high-density materials.
In the prior art, Zn is researched by utilizing a density functional theory12O12For the thermodynamic property of alkali metal (Li and Na) nano-encapsulation, the Gibbs free energy is found to be a negative value after the nano-encapsulation, and the stability of the alkali metal can be improved. Nano-encapsulation of active materials has not been achieved experimentally. The existing nano-encapsulation has encapsulation coating applied to relatively stable materials, and the existing technology realizes nano-encapsulation of a very small amount of metal by a method for synthesizing a legume-shaped carbon nano tube by a similar method respectively, but the type and the amount of the metal are greatly limited by the nano-encapsulation method for obtaining a small amount of inner coating metal in the process of synthesizing the carbon nano tube. In the prior art, the nano-encapsulation of carbon nanotubes on different metals and organic matters is realized by a vacuum sublimation filling method, the types and mass ratio of nano-encapsulated materials can be greatly improved, and the nano-encapsulation of phosphorus with poor stability is realized recently. However, the encapsulation of different materials by the carbon nanotubes has the problems of complexity, poor controllability, low yield and low mass ratio of the encapsulated material to the external encapsulating material, thereby limiting the practical application of the encapsulated material.
Meanwhile, the nano-encapsulation technology is also applied to the coating of the catalyst so as to prevent the catalyst from being poisoned. Prior art uses SiO2-mesoporous TiO2The hybrid hollow microspheres encapsulate the nano gold cyclohexane oxidation catalyst; in the prior art, a multinuclear core-shell Au-Co @ SiO is prepared by adopting a reverse micelle method2The nanospheres are treated to obtain the mononuclear nanospheres, so that the catalytic hydrogen production activity is improved. Nano-encapsulation coverThe idea is also used in the work of growing catalyst nanoparticles on a dendrimer skeleton. The method can control the dynamic process of material reaction by controlling the activity of the catalyst, and the catalytic method mostly improves the dynamic process of materials, but can not completely avoid the poisoning problem of the catalyst.
In the prior art, a thin-layer two-dimensional material is adopted to carry out nano encapsulation on an active material, so that the active material stably exists in the air, and meanwhile, the dynamic process of the active material is controlled by controlling the mass transfer process of different reaction components in the reaction. Unlike the catalytic method for promoting the kinetic reaction process, the nano-encapsulation method inhibits the mass transfer process of reaction components so as to inhibit the kinetic process of material reaction, and avoids the catalyst poisoning phenomenon which is difficult to avoid by the catalytic method. For example, the alkali metal, the hydride thereof and the aluminum hydride are subjected to nano packaging through the thin graphene, so that the crystal face of the graphene (002) is parallel to the outer surfaces of the alkali metal, the hydride thereof and the aluminum hydride, and the crystal face of the graphene (002) is tightly overlapped, so that water vapor and oxygen are prevented from entering through the graphene gap in the air to react with the alkali metal, the hydride thereof and the aluminum hydride which are active materials, the active materials are isolated from the external environment, the storage and transportation safety of the active materials is improved, and the distance between the graphene and the graphene is slowly opened in a liquid environment to realize the mass transfer of water molecules so as to realize the dynamic control of the active materials. As is known, alkali metal and hydride thereof and aluminum hydride are ideal solid hydrogen storage materials, and the alkali metal and hydride thereof and aluminum hydride solid hydrogen storage materials can overcome the problems of hydrogen storage and transportation at present, such as relatively small volume density of a high-pressure gaseous hydrogen storage method and harsh liquefaction conditions of low-temperature liquid hydrogen storage. Compared with gaseous and liquid hydrogen storage methods, solid-state hydrogen storage has significant advantages in the aspects of operation safety, energy efficiency and volume density, and is considered as the most promising hydrogen storage mode, but the existing reversible hydrogen storage materials cannot meet the comprehensive performance requirements of a vehicle-mounted hydrogen storage system in the aspects of weight/volume hydrogen storage density, operation temperature, hydrogen absorption/desorption rate, cycle performance and the like, so that solid-state hydrogen storage materials for hydrolyzing and releasing hydrogen, such as metal hydride and aluminum hydride, become an emerging research direction in the field of hydrogen storage materials. Different from high-temperature hydrogen release of reversible hydrogen storage, the solid hydrogen storage material for hydrolyzing hydrogen release can realize the hydrogen release requirement at different temperatures, even under severe winter conditions (such as-40 ℃). The solid hydrogen storage material capable of releasing hydrogen by hydrolysis, such as borohydride (sodium borohydride) used for general SUV in 2000, has high stability and high hydrogen storage quality (21%), is easy to store, can be hydrolyzed at room temperature to obtain hydrogen, but has the defects of difficult control of reaction rate, need of a noble metal catalyst to control the reaction kinetics, high cost and difficult recovery.
Compared with the problem that borohydride is difficult to recover, the hydrolysis hydrogen release solid hydrogen storage material of metal and hydride thereof and aluminum hydride is relatively easy to recover, and a noble metal catalyst is not needed in the hydrogen release process. However, when hydrolyzed to release hydrogen, the magnesium-based material and aluminum-based material will be hydrolyzed to form Mg (OH) as the main component on the surface2、Al(OH)3The passivation layer can prevent further reaction, other metal nano particles or other materials for adjusting pH value are added into water to promote the reaction, and the treatment processes further reduce the hydrogen storage mass ratio; AlH3Although having a high hydrogen storage mass ratio (20%), AlH3The synthesis is likely to be natural immediately and the reaction needs to be finished by heating, so that the hydrogen release at the subzero temperature is difficult to realize; CaH2The hydrogen storage quality is lower, and is only 9.6 percent under the condition of not calculating water; LiH, NaH, KH have high reactivity with water and risk of spontaneous combustion; alkali metal alanate LiAlH4And NaAlH4The hydrogen storage performance is excellent in all aspects, but the reaction speed is too high, the control is difficult, the storage is difficult, and the moisture and the oxygen in the air must be isolated when the hydrogen storage device is not used. In summary, the alkali metal and the hydride thereof and the aluminum hydride can be rapidly hydrolyzed to release hydrogen, but an explosive reaction is often formed instantly to release a large amount of hydrogen, the reaction is uncontrollable, and the storage and transportation process needs to be completely isolated from moisture and oxygen, which also brings certain challenges to the storage and transportation process.
Disclosure of Invention
The present invention aims to provide a nano-encapsulation structure with controllable active material dynamics and a preparation method thereof, so as to solve the problems.
In order to achieve the purpose, the invention adopts the following technical scheme:
a nanometer packaging structure enabling active material dynamics to be controllable comprises an active material, a thin-layer two-dimensional compact material, a curing packaging material and the active material, wherein the active material, the thin-layer two-dimensional compact material and the active material are spherical, and the thin-layer two-dimensional compact material is coated on the outer side of the active material to form a two-dimensional compact material coating layer; the solidified packaging material is coated on the outer side of the thin-layer two-dimensional compact material to form a nano packaging coating spherical structure of the active material.
Further, the coated active material sphere is a solid sphere, a hollow sphere or a porous sphere; the diameter of the coated active material spheres is 200 μm to 25 mm.
Furthermore, the number of the thin two-dimensional compact material (2) layers is 1-20, the thickness of the two-dimensional compact material coating layer is 1-100 atomic layer thickness, and the weight ratio of the two-dimensional compact material coating layer to the active material is 0.01-0.5%.
Further, a method for preparing the nano packaging structure with controllable active material dynamics comprises the following steps:
and 3, curing and packaging the surface of the active material ball coated with the two-dimensional thin-layer material through a mold for curing and packaging the material.
Further, in step 2, the step of coating the thin two-dimensional dense material on the surface of the active material comprises the following steps:
a) placing a two-dimensional material spherical high-pressure graphite sphere into a vessel containing dilute hydrochloric acid, ultrasonically cleaning at room temperature to remove tiny debris which easily fall off from the surface, and then drying;
b) mixing a sphere of a two-dimensional material and the coated microspheres according to the ratio of 1: 1-1: 5, mixing in a volume ratio to obtain a mixture A;
c) placing the mixture A into a container and sealing the container under inert atmosphere or vacuum, and then mechanically mixing the mixture A to ensure that two components in the mixture A generate rolling friction in the container to induce the two-dimensional material thin layer to be transferred from the surface of the two-dimensional material ball to the surface of the microsphere to obtain a mixture B;
d) and (4) taking the two-dimensional material ball out of the mixture B to obtain the two-dimensional material uniformly coated microsphere particles.
Further, the container is any one of a polytetrafluoroethylene sealed ball-milling tank, a stainless steel sealed ball-milling tank, a hard alloy sealed ball-milling tank, an alumina/corundum sealed ball-milling tank, a zirconia sealed ball-milling tank, a polyurethane ball sealed ball-milling tank, a silicon carbide sealed ball-milling tank, an agate ball sealed ball-milling tank or a nylon ball sealed ball-milling tank; the mechanical mixing method is ball milling mixing or roller mixing; the rotating speed of the ball milling mixing or roller machine is between 200rpm and 700 rpm; the ball milling time is 1h-96 h.
Furthermore, the volume ratio of the active material before nano-encapsulation to the whole material after nano-encapsulation is 0.1-0.95.
Further, the mold in the step 3 is a silica gel and graphite or metal alloy mold; the curing packaging material is resin or an alumina film; the thickness of the solidified packaging material is 0.02mm-4.5 mm.
Compared with the prior art, the invention has the following technical effects:
the nano-encapsulated active material can be stably stored in the air without harsh storage environment. The proportion of the active material of the invention can reach 2-93%.
The uncontrollable reaction of the nano-encapsulated active material can be regulated and controlled according to the actual application requirements.
The dynamic regulation and control of the invention does not need the participation of a catalyst, and avoids the problem of catalyst poisoning caused by the use of the catalyst. The invention is applied to a high-density solid hydrogen storage material for hydrolyzing and releasing hydrogen, a material system can obtain high hydrogen storage mass ratio, the hydrogen storage mass ratio can reach more than 20 wt% under the condition of no water, the water content can reach more than 10%, the hydrogen release can be controlled at the temperature of minus 40-100 ℃ and normal pressure, and the problems of difficult storage and transportation of hydrogen and the like are solved.
The nano packaging method has low cost and simple preparation steps, and is easy for industrial mass production.
Drawings
FIG. 1 is a schematic view of an active material encapsulation structure according to the present invention;
FIG. 2 is a pictorial representation of an active material of the present invention;
FIG. 3 is a pictorial view of a graphene coated active material, a two-dimensional sheet material, in accordance with the present invention;
fig. 4 is a diagram of a nano-encapsulated active material object of the present invention, namely, the graphene of fig. 3 is cured and encapsulated (a) by epoxy resin curing and (b) by curing and encapsulating an alumina film;
FIG. 5 is a graph of hydrogen evolution data for a lithium metal hydrolysis reaction according to the present invention;
wherein: the material comprises an active material 1, a thin two-dimensional compact material 2 and a curing packaging material 3.
Detailed Description
The invention is further described below with reference to the accompanying drawings:
referring to figures 1-5 of the drawings,
a nano packaging structure enabling active materials to be dynamically controllable comprises an active material 1, a thin-layer two-dimensional compact material 2 and a cured packaging material 3; the active material is spherical, the thin-layer two-dimensional compact material is coated on the outer side of the active material, and the curing packaging material is coated on the outer side of the thin-layer two-dimensional compact material to form a nano packaging and coating spherical structure of the active material.
The coated active material sphere is a solid sphere, a hollow sphere or a porous sphere; the diameter of the coated active material spheres is 200 μm to 25 mm.
The number of the layers of the thin two-dimensional compact material 2 is 1-20, the thickness of the two-dimensional compact material coating layer is 1-100 atomic layer thickness, and the weight ratio of the two-dimensional compact material coating layer to the active material is 0.01-0.5%.
A method for preparing a nano-encapsulation structure with controllable active material dynamics based on the nano-encapsulation coating spherical structure of the active material comprises the following steps:
and 3, curing and packaging the surface of the active material ball coated with the two-dimensional thin-layer material through a mold for curing and packaging the material.
In step 2, coating a thin two-dimensional dense material on the surface of the active material comprises the following steps:
a) placing a two-dimensional material spherical high-pressure graphite sphere into a vessel containing dilute hydrochloric acid, ultrasonically cleaning at room temperature to remove tiny debris which easily fall off from the surface, and then drying;
b) mixing a sphere of a two-dimensional material and the coated microspheres according to a certain volume ratio to obtain a mixture A;
c) placing the mixture A into a container and covering the container under inert atmosphere or vacuum, and then mechanically mixing to enable two components in the mixture A to generate rolling friction in the container to induce a two-dimensional material thin layer to be transferred from the surface of a two-dimensional material ball to the surface of a microsphere to obtain a mixture B;
d) and (4) taking the two-dimensional material ball out of the mixture B to obtain the two-dimensional material uniformly coated microsphere particles.
The container is any one of a polytetrafluoroethylene sealed ball-milling tank, a stainless steel sealed ball-milling tank, a hard alloy sealed ball-milling tank, an alumina/corundum sealed ball-milling tank, a zirconia sealed ball-milling tank, a polyurethane ball sealed ball-milling tank, a silicon carbide sealed ball-milling tank, an agate ball sealed ball-milling tank or a nylon ball sealed ball-milling tank; the mechanical mixing method is ball milling mixing or roller mixing; the rotating speed of the ball milling mixing or roller machine is between 200rpm and 700 rpm; the ball milling time is 1h-96 h.
The volume ratio of the active material before and after nano-encapsulation to the material after nano-encapsulation is 0.1-0.95.
The mould in the step 3 is a silica gel and graphite or metal alloy mould; the curing packaging material is resin or an alumina film; the thickness of the solidified packaging material is 0.02mm-4.5 mm.
The active material of the present invention is exemplified by alkali metal and hydride thereof and aluminum hydride, the two-dimensional dense material is exemplified by graphene, and the shell encapsulation is exemplified by resin or metal oxide film, and the present invention will be further described in detail with reference to the accompanying drawings and embodiments:
a) preparing active material small balls (see figure 2) by cutting or pressing under inert gas atmosphere, wherein the diameter of the small balls is between 200 mu m and 25mm, but the range is not limited;
b) coating a thin layer of compact low-layer non-functionalized graphene on the surface of the active material pellet in an inert atmosphere (see figure 3), wherein the mass ratio of the graphene to the active material is less than or equal to 1: 40;
c) the compact graphene thin layer coated on the surface of the active material is further cured, so that the problems of falling off of graphene in the subsequent treatment process and the like are solved. The curing treatment is carried out by respectively adopting two methods of resin curing and alumina film. Epoxy resin curing method: firstly, adding half of the mixed epoxy monomer and curing agent into the prepared spherical silica gel mold, placing the lithium ball into the corresponding silica gel spherical mold after about two minutes, then quickly injecting the other half of the mixed epoxy monomer and curing agent into the spherical silica gel mold, and taking out the cured and packaged active material pellet for standby after 30 minutes (as shown in fig. 4 (a)). The coating thickness of the epoxy is 0.3-4.5 mm, the effective mass ratio of the active material and the dynamic regulation degree of the active material can be controlled by controlling the thickness of the epoxy curing layer and the size ratio of the active material small balls, wherein the lower the thickness of the curing layer is relative to the size ratio of the active material small balls, the higher the effective mass ratio is, and the faster the reaction speed is. ② an alumina film curing method: the method comprises the steps of pressing aluminum foil paper with corresponding sizes respectively arranged above and below a lithium hydride aluminum ball coated with a two-dimensional material by a customized spherical die (as shown in fig. 4 (b)), controlling the opening speed and size of the interval between graphene layers in subsequent reaction by the pressing pressure of the upper aluminum foil paper and the lower aluminum foil paper, further controlling the reaction kinetic process of the lithium hydride aluminum ball, and simultaneously controlling the effective mass ratio of an active material and the kinetic regulation degree of the active material by controlling the thickness of the aluminum foil paper, wherein the thickness of the currently adopted aluminum foil comprises 0.02-0.5 mm, the smaller the coating thickness is, the lower the thickness of the aluminum oxide film is relative to the size ratio of small spheres of the active material, the higher the effective mass ratio is, and the faster.
d) According to the invention, the interlayer spacing of the thin two-dimensional compact material graphene is controlled under different environments, so that water vapor and oxygen are prevented from entering through the graphene gaps in the air to react with the active material alkali metal, hydride thereof and aluminum hydride, and the spacing between the graphene is slowly opened through soaking in liquid, so that the mass transfer process of different components is controlled, and the reaction kinetics are controlled. The dynamic process of the nano-encapsulated active material is tested by testing the hydrolysis hydrogen release speed of the active material with smaller total hydrogen release amount. After the nano-encapsulated active material is placed in the air for 10 days, the hydrogen release amount of the nano-encapsulated active material is tested again, and the hydrogen release amount is found to have no obvious change, so that the nano-encapsulated active material can stably exist in the air. The hydrogen hydrolysis and release speed of the nano-encapsulated active material lithium balls can be reduced to 1/3600 of non-encapsulated lithium balls with the same size, and the reaction rate can be regulated according to the encapsulation thickness and can be reacted at a constant speed within the range of 3.6-8114 ml/h/g. ② the dynamic process of the active material with larger hydrogen release amount can be detected by a drainage method. The hydrogen release speed of the nano-encapsulated active material lithium aluminum hydride can be reduced to 1/240 of the same-size unencapsulated lithium aluminum hydride ball, and the uniform reaction can be realized within the range of 68-3250 ml/h/g. Compared with the lithium hydride ball with the same size, the reaction speed of the nano-encapsulated active material lithium hydride ball with water in the air is reduced to 1/30, the reaction speed is controllable, and the safe and uniform hydrogen release can be achieved at 21890 ml/h/g. The required reaction speed can be selected by controlling the effective mass ratio of the active material and the dynamic regulation degree thereof according to the actual requirement by controlling the thickness of the alumina film and the size ratio of the active material balls.
Example 1:
a) referring to fig. 2, firstly, lithium metal is pressed into lithium balls with the sizes of 3mm, 5mm, 7mm, 9mm and 11mm respectively in a glove box (argon atmosphere);
b) referring to fig. 3, uniformly coating the prepared lithium spheres with nano-grade active material graphene in an inert gas atmosphere or vacuum for 36-72h, wherein the mass ratio of the graphene to the lithium spheres is less than or equal to 1: 40;
c) respectively selecting silica gel molds with the sizes of (4mm,6mm,8mm,10mm,12mm), (6mm,8mm,10mm,12mm,14mm), (10mm,12mm,14mm,16mm,18mm), (8mm,10mm,12mm,14mm,16mm), (12mm,14mm,16mm,18mm and 20mm), firstly adding half of the mixed epoxy monomer and curing agent into the prepared spherical silica gel mold, putting a lithium ball into the corresponding silica gel spherical mold after about two minutes, then quickly injecting the other half of the mixed epoxy monomer and curing agent into the spherical silica gel mold, and taking out the cured and packaged active material pellets for later use after 30 minutes. Wherein the corresponding coating thickness is (0.5mm,1.5mm,2.5mm,3.5mm,4.5mm)
The weight ratio of the active alkali metal lithium balls to the coated material is respectively 1-63%. The hydrogen storage mass ratio of the material system can reach 8.4%.
Example 2:
a) referring to fig. 2, a sodium block is cut in a glove box (argon atmosphere) and then pressed into sodium balls, wherein the size of each sodium ball is 11 mm;
b) referring to fig. 3, the prepared sodium spheres are uniformly coated with nano-scale active material graphene in an inert gas atmosphere or vacuum for 36-72h, wherein the mass ratio of graphene to sodium spheres is less than or equal to 1: 40;
c) selecting a silica gel mold with the size of (12mm,14mm,16mm,18mm and 20mm), adding half of the mixed epoxy monomer and curing agent into the prepared spherical silica gel mold, putting a sodium ball into the corresponding silica gel spherical mold after about two minutes, then quickly injecting the other half of the mixed epoxy monomer and curing agent into the spherical silica gel mold, and taking out the cured and packaged active material small ball for later use after 30 minutes. The corresponding coating thickness is (0.5mm,1.5mm,2.5mm,3.5mm,4.5mm), and the weight ratio of the active alkali metal sodium spheres to the coated material is 7-63%;
example 3 of implementation:
firstly, preparing an active material lithium aluminum hydride ball in a glove box (argon atmosphere), and pressing 0.75g of lithium aluminum hydride powder under 12MPa to prepare a lithium aluminum hydride ball with the diameter of 11 mm;
b) coating a thin layer of compact graphene (see figure 3) with a low layer number on the active surface in an inert atmosphere for 12-72h, wherein the mass ratio of the graphene to lithium aluminum hydride spheres is less than or equal to 1: 40;
c) punching 0.02mm of aluminum foil paper into wafers with the same size by using a 22mm fixed punch, respectively placing one aluminum foil paper on the upper part and the lower part of a lithium hydride aluminum ball coated by a two-dimensional material by using a customized spherical die for pressing, and further packaging, wherein the weight ratio of active alkali metal aluminum hydride lithium hydride aluminum ball to the coated material is 2-93%;
example 4 of implementation:
firstly, preparing active material lithium hydride pellets in a glove box (argon atmosphere), and pressing lithium hydride powder under 12MPa to form lithium hydride pellets with the diameter of 11 mm;
b) coating a thin layer of compact graphene (see figure 3) with a low layer number on the active surface in an inert atmosphere for 12-72h, wherein the mass ratio of the graphene to the lithium hydride spheres is less than or equal to 1: 40;
c) punching 0.02mm of aluminum foil paper into wafers with the same size by using a 22mm fixed punch, respectively placing one aluminum foil paper on the upper part and the lower part of the lithium hydride ball coated by the two-dimensional material by using a customized spherical die for pressing, and further packaging, wherein the weight ratio of the active alkali metal hydride lithium hydride ball to the coated material is 2-93%;
example 5 was carried out:
a, preparing active material sodium hydride pellets in a glove box (argon atmosphere), and pressing sodium hydride powder in the glove box (argon atmosphere) at 12MPa to prepare sodium hydride pellets with the diameter of 11 mm;
b) coating a thin layer of compact graphene (see figure 3) with a low layer number on the active surface in an inert atmosphere for 12-72h, wherein the mass ratio of the graphene to the sodium hydride spheres is less than or equal to 1: 40;
c) punching 0.02mm of aluminum foil paper into wafers with the same size by using a 22mm fixed punch, respectively placing the aluminum foil paper with the specified size on the upper part and the lower part of the sodium hydride ball coated by the two-dimensional material for further packaging, wherein the weight ratio of the active alkali metal hydride sodium hydride ball to the coated material is 2-93%;
the size of the active material can be determined according to actual requirements, and active material balls with larger sizes are optimally selected according to the standard of high hydrogen release conversion rate. The thinnest packaging material is selected on the premise of safe storage and transportation, so that the reduction of the hydrogen production quality ratio is reduced.
Application example 1:
the nano-encapsulated lithium metal spheres obtained in example 1 were used as a material for hydrogen release by hydrolysis.
Testing the hydrogen release performance of the hydrogen release material, wherein 1 hydrogen release material ball is placed in 120ml of water solution, and can slowly release hydrogen at a constant speed within 10 hours (see a gas chromatography test hydrogen release data chart of figure 5); measuring by gas chromatography, and calculating the amount of generated hydrogen by adopting an area external standard method; actually measuring the hydrogen release material of the small ball with the diameter of 8mm after the nano packaging of the metal lithium ball with the diameter of 7mm, wherein multiple groups of data show that the hydrogen release material nano packaged by the method has no loss when being hydrolyzed to release hydrogen after being placed for 10 days;
and (3) testing conditions are as follows: keeping the temperature at 6.5 ℃/normal temperature;
the hydrogen storage mass ratio of the hydrogen release material can reach 8.41 percent;
compared with the hydrogen release speed of the nano-encapsulated active material lithium ball of 1/3600 of the lithium ball without encapsulation in the same size, the reaction rate is controllable and can be controlled at a constant speed within the range of 3.6-8114 ml/h/g.
Application example 2:
nano-encapsulated lithium aluminum hydride pellets obtained in example 3 were used as a hydrolytic hydrogen releasing material.
a) The hydrogen release performance of the material is tested by adopting a simple drainage method device, 1 hydrogen release material ball is placed in 15ml of aqueous solution, and the nano-encapsulated lithium aluminum hydride ball can be maintained to release hydrogen at a constant speed within about 1 hour and has no loss during hydrolysis hydrogen release.
b) And (3) testing conditions are as follows: at normal temperature
c) The material system can obtain high hydrogen storage mass ratio which can reach more than 20wt percent, and can also reach more than 10wt percent under the condition of including water,
d) the hydrogen release speed of the nano-encapsulated active material lithium aluminum hydride can be reduced to 1/240 without lithium aluminum hydride balls with the same size, and the reaction speed is uniform and controllable within the range of 68-3250 ml/h/g.
Application example 3:
lithium metal, sodium metal, lithium aluminum hydride, lithium hydride, sodium hydride, etc. can be exposed to the air at normal temperature and pressure by the nano-encapsulation method of embodiment examples 1,2,3,4, 5. The active material can be stably existed, thereby reducing the problem of difficult storage and transportation.
Application example 4:
constructing a new material system with high hydrogen storage capacity under the condition of low temperature. The method can fully utilize the national power grid electricity abandonment, electrolyze the hydrolysis products of examples 1,2,3,4,5 and the like, can also regenerate alkali metal and hydride thereof and aluminum hydride by the products at high temperature and high pressure, and treat the products by the nano packaging method, and transports the nano packaged solid hydrogen storage material to a hydrogen using area, namely converts the power grid electricity abandonment into hydrogen energy to be transported out, thereby realizing green electric power energy storage.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
Claims (8)
1. A nano-encapsulation structure enabling active material dynamics to be controllable is characterized by comprising an active material (1), a thin-layer two-dimensional compact material (2) and a solidified encapsulation material (3); the active material is spherical, the thin-layer two-dimensional compact material is coated on the outer side of the active material, a thin-layer two-dimensional compact material coating layer is formed on the surface of the active material, the thin-layer two-dimensional compact material coating layer changes the surface activity of the active material, and the mass transfer of liquid molecules during reaction in liquid is realized by controlling the interlayer spacing of the thin-layer two-dimensional compact material to be slowly opened, so that the reaction kinetics are controlled; the solidified packaging material is coated on the outer side of the thin-layer two-dimensional compact material to form a nano packaging coating spherical structure of the active material; the curing packaging material is resin or an alumina film; the position of the active material entering the liquid during soaking is controlled by controlling surface air holes of the solidified packaging material resin and gaps formed by pressing an upper piece and a lower piece of aluminum oxide films, so that the active material is further controllable in dynamics.
2. The active material dynamics-controllable nano-encapsulation structure according to claim 1, wherein the coated active material spheres are solid spheres, hollow spheres or porous spheres; the diameter of the coated active material spheres is 200 μm to 25 mm.
3. The nano-encapsulation structure enabling the kinetic control of the active material according to claim 1, wherein the number of the thin two-dimensional dense material (2) layers is 1 to 20, the thickness of the two-dimensional dense material coating layer is 1 to 100 atomic layer thickness, and the weight ratio of the two-dimensional dense material coating layer to the active material is between 0.01% and 0.5%.
4. A method for preparing a nano-encapsulation structure enabling active material kinetics control according to any one of claims 1 to 3, comprising the steps of:
step 1, firstly, preparing an active material ball by adopting a cutting, pressing or polishing method in an inert gas atmosphere;
step 2, coating a thin two-dimensional compact material on the surface of the active material ball in an inert atmosphere or vacuum;
step 3, curing and packaging the surface of the active material ball coated with the thin-layer two-dimensional compact material through a mold for curing and packaging the material; the mould is used by combining two hemispherical parts; the aluminum oxide film curing packaging material is divided into an upper sheet and a lower sheet.
5. The method for preparing nano packaging structure with controllable active material dynamics as claimed in claim 4, wherein the step 2 of coating the surface of the active material ball with a thin two-dimensional dense material comprises the following steps:
a) putting the high-pressure graphite balls into a vessel containing dilute hydrochloric acid, ultrasonically cleaning at room temperature to remove small chips which easily fall off from the surface, and then drying;
b) high-pressure graphite nodules and coated active material nodules are mixed according to the weight ratio of 1: 1-1: 5, mixing in a volume ratio to obtain a mixture A;
c) placing the mixture A into a container and sealing the container under inert atmosphere or vacuum, and then mechanically mixing the mixture A to ensure that two components in the mixture A generate rolling friction in the container to induce a two-dimensional material thin layer to be transferred from the surface of a high-pressure graphite sphere to the surface of an active material sphere to obtain a mixture B;
d) and taking out the high-pressure graphite spheres from the mixture B to obtain the active material spheres uniformly coated by the thin-layer two-dimensional compact material.
6. The method for preparing a nano-encapsulation structure enabling active material dynamics to be controlled according to claim 5, wherein the container is any one of a polytetrafluoroethylene sealed ball-milling jar, a stainless steel sealed ball-milling jar, a cemented carbide sealed ball-milling jar, an alumina/corundum sealed ball-milling jar, a zirconia sealed ball-milling jar, a polyurethane ball sealed ball-milling jar, a silicon carbide sealed ball-milling jar, an agate ball sealed ball-milling jar or a nylon ball sealed ball-milling jar; the mechanical mixing method is ball milling mixing or roller mixing; the rotating speed of the ball milling mixing or roller machine is between 200rpm and 700 rpm; the ball milling time is 1h-96 h.
7. The nano-encapsulation structure enabling active material kinetics control according to claim 1, wherein a volume ratio of the active material before nano-encapsulation to the bulk material after nano-encapsulation is 0.1 to 0.95.
8. The method for preparing nano packaging structure with controllable active material kinetics as claimed in claim 4, wherein the mold in step 3 is a silica gel or metal alloy mold; the thickness of the solidified packaging material is 0.02mm-4.5 mm.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101733050A (en) * | 2008-11-20 | 2010-06-16 | 美国吉姆迪生物科技有限公司 | Nanometer and micropackaging, and raw material discharge |
| CN102351143A (en) * | 2010-06-02 | 2012-02-15 | 通用汽车环球科技运作有限责任公司 | Packaged reactive materials and method for making the same |
| CN105947977A (en) * | 2016-04-25 | 2016-09-21 | 东莞市联洲知识产权运营管理有限公司 | Novel nano-hydroboron hydrogen storage material and preparation method thereof |
| CN107226476A (en) * | 2016-09-28 | 2017-10-03 | 西安交通大学 | Two-dimensional thin-layer material coated on surface of microsphere and simple stripping method thereof |
| CN108193107A (en) * | 2017-12-21 | 2018-06-22 | 陕西科技大学 | A kind of novel organic coating core-shell structure copolymer nanocomposite hydrogen storage material and preparation method thereof |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101733050A (en) * | 2008-11-20 | 2010-06-16 | 美国吉姆迪生物科技有限公司 | Nanometer and micropackaging, and raw material discharge |
| CN102351143A (en) * | 2010-06-02 | 2012-02-15 | 通用汽车环球科技运作有限责任公司 | Packaged reactive materials and method for making the same |
| CN105947977A (en) * | 2016-04-25 | 2016-09-21 | 东莞市联洲知识产权运营管理有限公司 | Novel nano-hydroboron hydrogen storage material and preparation method thereof |
| CN107226476A (en) * | 2016-09-28 | 2017-10-03 | 西安交通大学 | Two-dimensional thin-layer material coated on surface of microsphere and simple stripping method thereof |
| CN108193107A (en) * | 2017-12-21 | 2018-06-22 | 陕西科技大学 | A kind of novel organic coating core-shell structure copolymer nanocomposite hydrogen storage material and preparation method thereof |
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