CN1966396B - A kind of inorganic porous nanotube and preparation method thereof - Google Patents

Abstract

The invention relates to the construction of inorganic compound nanotubes by combining layer-by-layer assembly technology and surface gel sol technology. Firstly, the principle of surface gel sol technology is used, through the reaction between the active groups between the two substances and the different electrical properties between the two substances. The adsorption reaction produces multicomponent nanotubes, and then removes one of the components to form a single component inorganic compound porous nanotube. These two substances include: compounds with alkoxy groups, which are hydrolyzed into inorganic compounds, and then assembled into two-component nanotubes layer by layer through hydrogen bonds or chemical bonds to interact with compounds or biomolecules, and then remove the organic components , that is, porous nanotubes of inorganic compounds. The present invention uses the organic matter that is easy to remove and has chemical interaction with components as a template to form a porous inorganic compound nanotube with a high specific surface area and a mesopore diameter range, which has extremely high applications in catalysis and hydrogen storage. value.

Description

A kind of inorganic porous nanotube and preparation method thereof

technical field

The invention relates to a new inorganic porous nanotube and its preparation method, especially to an inorganic porous nanotube prepared by combining layer-by-layer assembly technology and surface gel-sol technology and its preparation method, especially using layer-by-layer assembly technology and surface gel-sol technology Porous titania nanotubes prepared by gel-sol technique and preparation method thereof.

Background technique

The famous physicist and Nobel Prize winner Richard Feynman (R. Feynman) asked in 1959, "If one day we can arrange atoms one by one according to human will, what kind of miracle will it produce?" ?” Today, the birth and development of nanotechnology is gradually turning this beautiful vision into reality.

New materials are the material basis and forerunner for the development of high technology. Just as the discovery and application of semiconductors in the 1950s promoted the development of microelectronics and triggered the information-centered new technology revolution in the 1970s, nanomaterials have become Become the most dynamic growth point in the research of new materials in the 21st century. Ultramicronization, high-density integration and high spatial resolution of components require materials to be smaller in size and higher in performance. Nanomaterials and nanotechnology will serve as the forerunners of high-tech development.

With the continuous development of nanostructured materials, its research connotation has been continuously broadened, and its research objects have also been continuously enriched. It not only involves solid materials such as nanoparticles, nanowires, and nanofilms, but also involves materials containing non-physical nanospaces. (microporous and mesoporous materials, etc.) and ordered nanostructures and their assembled system materials. For the nano-assembly system, not only the solid units of nano-units are included, but also the matrix with nano-scale space supporting them.

Mesoporous solids and mesoporous composites are attractive research objects in the field of nanomaterials science in recent years. Because of their high porosity (pore size 2-50nm) and high specific surface area, they are widely used in adsorption, filtration etc. have important application prospects. Nanoporous TiO ₂ is a kind of mesoporous material. In addition to the above characteristics, there is also a remarkable feature of high photocatalytic activity. The photocatalytic degradation of organic matter water treatment technology using it has no secondary pollution and cleanliness. The advantage of high, nanoporous _TiO2 is that it has a large specific surface area, which can maximize the adsorption of organic substances on its surface. In addition, nanoporous TiO ₂ also has stronger ultraviolet absorption ability, resulting in stronger photocatalytic degradation ability, so that it can quickly decompose the organic matter adsorbed on its surface. Papermaking enterprises have provided strong technical support. Therefore, nanoporous TiO ₂ has also become one of the hot topics in the current scientific research.

In order to better study the formation conditions and various properties of porous nanotubes, the research group that made this invention first reported the use of layer-by-layer assembly technology to construct polyelectrolyte nanotubes (J.Am.Chem.Soc.125(2003)11140) . On this basis, our research group continued to combine layer-by-layer assembly technology and surface gel-sol technology to construct porous nanotubes, and made a comprehensive and systematic analysis and detection of their morphology and properties. Facts have proved that using the combination of layer-by-layer assembly technology and surface gel sol technology, the prepared porous nanotubes have a large specific surface area and a large porosity, which makes them useful in photocatalysis, fuel cells and hydrogen storage. The application has laid a good foundation.

Contents of the invention

An object of the present invention is to provide a new type of inorganic porous nanotube, which is prepared by combining layer-by-layer assembly technology and surface gel sol technology by means of the interaction between adjacent components.

Another object of the present invention is to provide a new method for preparing inorganic porous nanotubes, which is carried out by combining layer-by-layer assembly technology and surface gel sol technology by means of the interaction between adjacent components.

According to one aspect of the present invention, the present invention provides an inorganic porous nanotube, including a porous nanotube formed of metal oxide or metal sulfide, and the pore diameter of the inorganic porous nanotube is between 1 nm and 500 nm.

Preferably, the metal oxide or metal sulfide is selected from: titanium dioxide, zinc oxide, zinc sulfide, manganese oxide, manganese sulfide.

More preferably, the metal oxide is titanium dioxide; or zinc oxide or manganese oxide; or zinc sulfide or manganese sulfide.

The inorganic porous nanotube is formed through the following steps:

First, the template with the microscopic morphology is placed into the solution of the compound with the first group;

Then take out the template and put it into water or aqueous solution for hydrolysis;

Then put the hydrolyzed template into the solution of the compound or biomolecule with the second group, and form a bond with the compound or biomolecule with the second group;

Finally, the compound or biomolecule with the second group is removed.

Preferably, the compound having the first group is selected from inorganic acid salts of transition metals, organic acid salts of transition metals, with the proviso that the inorganic acid salts of transition metals, organic acid salts of transition metals can be hydrolyzed to transition metal oxides ;

and the compound or biomolecule having the second group is selected from compounds or biomolecules having a hydrogen bond or chemical bond;

The proviso is that the compound with the first group is different from the compound or biomolecule with the second group, and the compound or biomolecule with the second group is easy to remove.

Preferably, the compound with the first group is selected from metal compounds with alkoxy groups, metal compounds with acid chloride or acid anhydride groups, and the compound with the first group can be hydrolyzed into corresponding metal salts.

More preferably, the compound having the first group is selected from titanium alkoxide, titanium inorganic acid, titanium chloride, zinc organic acid, manganese organic acid.

Most preferably, the compound having the first group is selected from Ti(OBu) ₄ , TiCl ₄ , Zn(OAC) ₂ , Mn(OAC) ₂ .

Preferably, the specific surface area of the inorganic porous nanotube is 100-300 m ² /g, and the porosity is 2-7 nm.

More preferably, the specific surface area of the inorganic porous nanotube is 103m ² /g, and the porosity is 2-3nm.

Preferably, the template with microscopic porous morphology is selected from alumina membrane and polycarbonate membrane.

More preferably, the template with microporous morphology is selected from aluminum oxide membranes or polyester membranes with a pore diameter of 20-500 nm and a diameter of 1-5 cm.

Most preferably, the template with microscopic porous morphology is an aluminum oxide film.

According to one aspect of the present invention, the present invention provides a method for preparing inorganic porous nanotubes, comprising the following steps:

a. Putting the template with the microporous morphology into the anhydrous solvent solution dissolved with the compound having the first group for a period of time;

b. taking out the template and putting it into water for a period of time to hydrolyze the compound with the first group to generate an inorganic compound;

c. Putting the template into a solution of a compound having a second group or a biomolecule prepared in an anhydrous solvent for a period of time;

e. placing the template in a high temperature or other environment to remove the compound or biomolecule with the second group to form inorganic porous nanotubes generated by hydrolysis of the compound with the first group.

Wherein, the compound having the first group is selected from inorganic acid salts of transition metals and organic acid salts of transition metals, provided that the inorganic acid salts of transition metals and organic acid salts of transition metals can be hydrolyzed into transition metal oxides thing;

And the compound or biomolecule with the second group is selected from compounds or biomolecules that can form hydrogen bonds or chemical bonds;

The proviso is that the compound with the first group is different from the compound or biomolecule with the second group and that the compound or biomolecule with the second group is easy to remove.

The preparation method of the inorganic porous nanotube further comprises the following steps:

d. Repeat steps a, b, and c multiple times in order to obtain the corresponding number of layers, which can ensure that after the compound or biomolecule with the second group is removed, it will be generated by the hydrolysis of the compound of the first group Stable Presence of Inorganic Compounds in Porous Nanotubes.

Preferably, according to the method for preparing inorganic porous nanotubes of the present invention, wherein the compound having the first group is selected from metal compounds having alkoxy groups, metal compounds having acid chloride or acid anhydride groups, and the compound having the first group The compound can be hydrolyzed to the corresponding metal salt.

Wherein, the compound or biomolecule having the second group is selected from polyacrylic acid, polystyrene sulfonic acid, and polyvinylamine.

Wherein, the template is selected from alumina templates and polycarbonate templates. More preferably, the template is selected from an alumina template or a polycarbonate template modified with trimethoxyethylaminosilane.

Wherein, the concentration of polyacrylic acid is between 0.01% and 10% of solute mass to volume volume.

Preferably, the concentration of polyacrylic acid is such that the percentage of solute mass to solvent volume is between 1% and 10%.

Wherein, the compound having the first group is selected from titanium alkoxide, titanium inorganic acid, titanium chloride, zinc organic acid, manganese organic acid.

Preferably, the compound having the first group is selected from Ti(OBu) ₄ , TiCl ₄ , Zn(OAC) ₂ , Mn(OAC) ₂ .

Preferably, the concentration of titanium alkoxide or titanium inorganic acid is between 0.1% and 10% of solute mass to volume volume.

More preferably, the concentration of titanium alkoxide or titanium inorganic acid is between 1% and 10% of solute mass to volume volume.

Preferably, step e is burning at high temperature in a muffle furnace for a period of time to remove the compound with the second group and biomolecules from the template.

Preferably, step d repeats step a, step b and step c in sequence for about 10 to 30 times in order to ensure sufficient adsorption time.

According to the preparation method of porous inorganic nanotubes of the present invention, further comprising the following steps:

f. Preparation of scanning samples: put the template into 1-6M NaOH aqueous solution for 30 minutes to 2 hours, remove the NaOH solution, rinse with water and ethanol, and place the template in ethanol for ultrasonic dispersion, wait use.

According to the preparation method of porous inorganic nanotubes of the present invention, further comprising the following steps:

g. Preparation of transmission electron microscope samples: put the template into 1-6M NaOH aqueous solution for 30 minutes to 2 hours, remove the NaOH solution, rinse with water and ethanol, and dialyze with water for 24-48 hours, after ultrasonic treatment The solution was dropped on the support film copper grid, and the transmission experiment was done after drying.

According to the method for preparing porous inorganic nanotubes of the present invention, the hydrolysis step is one-step hydrolysis.

According to the method for preparing porous inorganic nanotubes of the present invention, the hydrolysis step is multi-step hydrolysis.

According to the preparation method of the porous inorganic nanotube of the present invention, the treatment of the template is to immerse it in water for a period of time.

According to the preparation method of the porous inorganic nanotube of the present invention, the treatment of the template is soaking it in absolute ethanol for a period of time.

The present invention combines layer-by-layer assembly technology and surface gel sol technology, and adopts template method to prepare porous nanotubes with high specific surface area and porosity, laying a good foundation for its application in photocatalysis and hydrogen storage.

The present invention uses chemical bonding and hydrogen bonding between adjacent components to construct porous nanotubes with two or more components using layer-by-layer assembly method, surface gel sol method and template method. A component that forms porous nanotubes. The nanotubes formed by this method have a porous structure with high specific surface area and porosity, which is convenient for their applications in photocatalysis and other aspects. groundbreaking.

Description of drawings

Fig. 1a, Fig. 1b are the scanning electron microscope (SEM) pictures of the front and back side of aluminum oxide template in the method of the present invention respectively;

Fig. 2a, Fig. _2b are TiO prepared in embodiment 1 respectively Scanning electron microscope (SEM) pictures of inorganic porous nanotubes;

Figure 3a is a transmission electron microscope (TEM) picture of the _TiO2 inorganic porous nanotubes prepared in Example 1; Figure 3b is a high-resolution transmission electron microscope (TEM) picture of the _TiO2 inorganic porous nanotubes prepared in Example 1.

4 is an electron energy dispersive energy spectrum (EDX) diagram of TiO ₂ inorganic porous nanotubes prepared in Example 1.

Detailed ways

According to a specific embodiment of the present invention, an inorganic porous nanotube is provided, including a porous nanotube formed of metal oxide or metal sulfide, and the pore diameter of the inorganic porous nanotube is between 1 nm and 500 nm.

In a preferred embodiment, wherein the metal oxide or metal sulfide is selected from: titanium dioxide, zinc oxide, zinc sulfide, manganese oxide, manganese sulfide.

In a more preferred embodiment, the metal oxide is titanium dioxide; or zinc oxide or manganese oxide; or zinc sulfide or manganese sulfide.

In a specific embodiment, the inorganic porous nanotube is formed by the following steps:

First, the template with the microscopic morphology is placed into the solution of the compound with the first group;

Then take out the template and put it into water or aqueous solution for hydrolysis;

Then put the hydrolyzed template into the solution of the compound or biomolecule with the second group, and form a bond with the compound or biomolecule with the second group;

Finally, the compound or biomolecule with the second group is removed.

In a specific preferred embodiment, the compound having the first group is selected from inorganic acid salts of transition metals and organic acid salts of transition metals, provided that the inorganic acid salts of transition metals and organic acid salts of transition metals can be hydrolyzed into transition metal oxides;

and the compound or biomolecule having the second group is selected from compounds or biomolecules having a hydrogen bond or chemical bond;

The proviso is that the compound with the first group is different from the compound or biomolecule with the second group, and the compound or biomolecule with the second group is easy to remove.

In a preferred embodiment, wherein the compound with the first group is selected from metal compounds with alkoxy groups, metal compounds with acid chloride or acid anhydride groups, and the compound with the first group can be hydrolyzed into the corresponding of metal salts.

In a more preferred embodiment, the compound having the first group is selected from titanium alkoxide, titanium inorganic acid, titanium chloride, zinc organic acid, manganese organic acid.

In a most preferred embodiment, the compound having the first group is selected from Ti(OBu) ₄ , TiCl ₄ , Zn(OAC) ₂ , Mn(OAC) ₂ .

In a preferred embodiment, the specific surface area of the inorganic porous nanotube is 100-300 m ² /g, and the porosity is 2-7 nm.

In a more preferred embodiment, the specific surface area of the inorganic porous nanotube is 103 m ² /g, and the porosity is 2-5 nm.

In a preferred embodiment, the template with microscopic porous morphology is selected from alumina membrane and polycarbonate membrane.

In a more preferred embodiment, the template with microporous morphology is selected from aluminum oxide membranes or polyester membranes with a pore diameter of 20-500 nm and a diameter of 1-3 cm.

Most preferably, the template with microporous morphology is an alumina template or a polycarbonate template modified with trimethoxyethylaminosilane.

According to another aspect of the present invention, in a specific embodiment, the present invention provides a method for preparing inorganic porous nanotubes, comprising the following steps:

a. Putting the template with the microporous morphology into the anhydrous solvent solution dissolved with the compound having the first group for a period of time;

b. taking out the template and putting it into water for a period of time to hydrolyze the compound with the first group to generate an inorganic compound;

c. Putting the template into a solution of a compound having a second group or a biomolecule prepared in an anhydrous solvent for a period of time;

e. placing the template in a high temperature or other environment to remove the compound or biomolecule with the second group to form inorganic porous nanotubes generated by hydrolysis of the compound with the first group.

Wherein, the compound having the first group is selected from inorganic acid salts of transition metals and organic acid salts of transition metals, provided that the inorganic acid salts of transition metals and organic acid salts of transition metals can be hydrolyzed into transition metal oxides thing;

And the compound or biomolecule with the second group is selected from compounds or biomolecules that can form hydrogen bonds or chemical bonds;

The proviso is that the compound with the first group is different from the compound or biomolecule with the second group and that the compound or biomolecule with the second group is easy to remove.

The preparation method of the inorganic porous nanotube further comprises the following steps:

d. Repeat steps a, b, and c multiple times in order to obtain the corresponding number of layers, which can ensure that after the compound or biomolecule with the second group is removed, it will be generated by the hydrolysis of the compound of the first group Stable Presence of Inorganic Compounds in Porous Nanotubes.

In a preferred embodiment, according to the preparation method of inorganic porous nanotubes of the present invention, wherein the compound having the first group is selected from metal compounds having alkoxy groups, metal compounds having acid chloride or acid anhydride groups, and the Compounds with a first group are capable of hydrolysis to the corresponding metal salt.

In a preferred embodiment, the compound or biomolecule having the second group is selected from polyacrylic acid, polystyrenesulfonic acid, polyvinylamine.

In a preferred embodiment, the concentration of polyacrylic acid is between 0.01% and 10% of the mass of solute to volume.

In a more preferred embodiment, the concentration of polyacrylic acid is such that the percentage of solute mass to solvent volume is between 1% and 10%.

In a preferred embodiment, the compound having the first group is selected from titanium alkoxide, titanium inorganic acid, titanium chloride, zinc organic acid, manganese organic acid.

In a more preferred embodiment, the compound having the first group is selected from Ti(OBu) ₄ , TiCl ₄ , Zn(OAC) ₂ , Mn(OAC) ₂ .

In a preferred embodiment, the concentration of titanium alkoxide or titanium inorganic acid is between 0.1% and 10% of solute mass to volume.

In a more preferred embodiment, the concentration of titanium alkoxide or titanium inorganic acid is between 1% and 10% of solute mass to volume volume.

In a preferred specific embodiment, step e is burning at a high temperature in a muffle furnace for a period of time to remove the compound with the second group and the biomolecule from the template.

In a preferred embodiment, step d repeats step a, step b and step c in sequence for about 10 to 30 times in order to ensure sufficient adsorption time.

In a preferred embodiment, the method for preparing porous inorganic nanotubes according to the present invention further comprises the following steps:

f. Preparation of scanning samples: put the template into 1-6M NaOH aqueous solution for 30 minutes to 2 hours, remove the NaOH solution, rinse with water and ethanol, and place the template in ethanol for ultrasonic dispersion, wait use.

In a preferred embodiment, the method for preparing porous inorganic nanotubes according to the present invention further comprises the following steps:

g. Preparation of transmission electron microscope samples: put the template into 1-6M NaOH aqueous solution for 30 minutes to 2 hours, remove the NaOH solution, rinse with water and ethanol, and dialyze with water for 24-48 hours, after ultrasonic treatment The solution was dropped on the support film copper grid, and the transmission experiment was done after drying.

In a preferred embodiment, according to the method for preparing porous inorganic nanotubes of the present invention, the hydrolysis step is one-step hydrolysis.

In a preferred embodiment, according to the method for preparing porous inorganic nanotubes of the present invention, the hydrolysis step is multi-step hydrolysis.

In a preferred embodiment, according to the method for preparing porous inorganic nanotubes of the present invention, the treatment of the template is to soak it in water for a period of time.

In a preferred embodiment, according to the method for preparing porous inorganic nanotubes of the present invention, the template is soaked in absolute ethanol for a period of time.

The present invention combines layer-by-layer assembly technology and surface gel sol technology, and adopts template method to prepare porous nanotubes with high specific surface area and porosity, laying a good foundation for its application in photocatalysis and hydrogen storage.

In order to enable those skilled in the art to implement the present invention, the preferred embodiments of the present invention are now described in detail, but it should be understood that the content of the present invention is not limited to the description herein.

Specific examples.

Example 1 TiO _Inorganic porous nanotubes formed by metal salts with alkoxy groups and high molecular weight polymers of organic acids

First, 1.736 grams of alkoxy metal salt Ti(OBu) ₄ (nominal Ti ⁿ (OBu) ₄ , commercially available from Acros Company) was dissolved in 50 ml of anhydrous methanol:anhydrous toluene (volume ratio of 1:1) In the solvent, the concentration is about 100mM; secondly, 5g of polyacrylic acid (PAA) is dissolved in 10ml of anhydrous methanol solution, and the concentration is about 10mM.

First put the alumina template into the Ti(OBu) ₄ solution for 30 minutes, then put the alumina template into pure water for 2 minutes for hydrolysis; then put the alumina template into the polyacrylic acid solution for 50 minutes, after full adsorption, Make both fully responsive. Repeat the above operation more than 10 times, take out the template after sintering in a muffle furnace at 400°C for 24 hours, soak in 6M sodium hydroxide solution for 60 minutes, wash and filter with clean water, and disperse the nanotubes in pure water.

The prepared alumina template can be stuck on the silicon wafer, soaked in 0.1-10M NaOH solution for 2-6 hours, soaked in pure water for 3 times after taking it out, and blown dry with nitrogen to prepare scanning electron microscope samples; or The above-mentioned alumina template after the reaction is directly soaked in the above-mentioned NaOH solution for 2-6 hours, and then dialyzed with a large amount of water for 24-48 hours, centrifuged and ultrasonically treated to obtain a nanotube solution, and the solution is dropped on the supporting membrane copper grid, After drying, transmittance test was carried out.

Figures 1a and 1b are scanning electron microscope pictures of the front and back sides of the alumina template used in this example; TiO Scanning electron micrograph of inorganic porous nanotube; Fig. 3 is the transmission electron microscopic image of _TiO2 inorganic porous nanotube formed by the macromolecule of alkoxide metal salt and organic acid as prepared above; Fig _. 4 is prepared as above Electron energy dispersive energy spectroscopy (EDX) diagram of _TiO2 inorganic porous nanotubes formed by metal alkoxide salts and organic acid polymers.

The specific surface area of the TiO ₂ nanotube prepared by the above method is 103m ² /g, and the porosity is 2-3nm.

Embodiment 2 is formed by the polymer of titanium chloride and organic acid TiO ₂ Inorganic porous nanotubes

First, 1.555 grams of titanium chloride TiCl ₄ was dissolved in 50 ml of absolute ethanol solvent, the concentration was about 100 mM; secondly, 5 g of polyacrylic acid (PAA) acidic solution was dissolved in 10 ml of anhydrous methanol solution, the concentration was about 10 mM.

First put the alumina template into the titanium chloride solution for 30 minutes, then put the alumina template into pure water for 2 minutes and then put the alumina template into the polyacrylic acid solution for 50 minutes. respond adequately. Repeat the above operation more than 10 times, take out the template after sintering in a muffle furnace at 400°C for 24 hours, soak in 6M sodium hydroxide solution for 60 minutes, wash and filter with clean water, and disperse the nanotubes in pure water.

Example 3 ZnS inorganic porous nanotubes formed by multi-step hydrolysis of metal salts with acetate and polymers of organic acids

First prepare 91 mM zinc acetate Zn (OAC) ₂ aqueous solution, and then dissolve 5 g of polyacrylic acid (PAA) acidic solution in 10 ml of anhydrous methanol solution, the concentration is about 10 mM.

First put the alumina template into Zn(OAC) ₂ aqueous solution for 30 minutes, then put the alumina template into pure water for 2 minutes and then transfer the alumina template to Na ₂ S aqueous solution (4mM, pH=11.05 ), take it out after 10 minutes, and also wash and dry it with water. This operation can prepare the ZnS film, and then put the alumina template into the polyacrylic acid solution for 50 minutes. After fully adsorbing, the two can fully react. Repeat the above operation more than 30 times, take out the template after sintering in a muffle furnace at 400°C for 24 hours, soak it in 6M sodium hydroxide solution for 60 minutes, wash and filter with clean water, and disperse the ZnS porous nanotubes in pure water.

In this experiment, an appropriate proportion of Mn(OAC) ₂ and Zn(OAC) ₂ aqueous solutions can also be used to obtain Mn ²⁺ doped ZnS porous nanotubes.

Example 4 ZnO inorganic porous nanotubes formed by multi-step hydrolysis of metal salts with acetate and polymers of organic acids

To prepare ZnO nanotubes, it is necessary to use a template with a stronger binding force to Zn(OAC) ₂ and to modify the inner wall with amino groups, and alternately soak this template in Zn(OAC) ₂ and NaOH aqueous solution.

First prepare 91mM zinc acetate Zn(OAC) ₂ aqueous solution with Zn(OAC) ₂ , then dissolve 5g of polyacrylic acid (PAA) acidic solution in 10ml of anhydrous methanol solution, the concentration is about 10mM.

First, the polycarbonate template whose inner wall is modified by trimethoxyethylaminosilane is put into Zn(OAC) ₂ aqueous solution for 30 minutes, then the polycarbonate template is put into NaOH aqueous solution and hydrolyzed for 2 minutes; The aluminum oxide template was transferred to Na ₂ S aqueous solution (4mM, pH=11.05), taken out after 10 minutes, washed and dried in the same way, this operation can prepare ZnS film, and then put the polycarbonate template into the polyacrylic acid solution for 50 Minutes, after full adsorption, make the two fully react. Repeat the operation more than 10 times, and take out the template after sintering in a muffle furnace at 400° C. for 24 hours to obtain ZnO nanotubes.

Scanning electron microscope samples can be prepared with reference to the methods in the examples.

Example 5 TiO _Inorganic porous nanotubes formed by metal salts with alkoxy groups and organic polymers

First, 1.736 grams of alkoxy metal salt Ti(OBu) ₄ (nominal Ti ⁿ (OBu) ₄ , commercially available from Acros Company) was dissolved in 50 ml of anhydrous methanol:anhydrous toluene (volume ratio of 1:1) In the solvent, the concentration is about 100mM; secondly, 5g of polyvinylamine (PEI) is dissolved in 10ml of anhydrous methanol solution, and the concentration is about 10mM.

Put the alumina template into the Ti(OBu) ₄ solution for 30 minutes, then put the alumina template into pure water for 2 minutes; then put the alumina template into the polyvinyl acid solution for 50 minutes, fully absorb After that, make the two fully react. Repeat the operation more than 10 times, take out the template after sintering in a muffle furnace at 400°C for 24 hours, soak in 6M sodium hydroxide aqueous solution for 60 minutes, wash and filter with clean water, and disperse the nanotubes in pure water.

The present invention uses the chemical bonding and hydrogen bonding interactions between adjacent components to construct porous nanotubes with two or more components using layer-by-layer assembly method, surface gel sol method and template method. A component of nanotubes that form porous nanotubes. The nanotubes formed by this method have a porous structure and have a high specific surface area and porosity, which is convenient for its application in photocatalysis and other aspects.

The inorganic porous nanotubes of TiO ₂ , ZnS, ZnO, MgO, and MgS prepared by the above embodiments have the advantages of avoiding collapse and having a porosity between mesopores.

The above descriptions are only typical embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

references

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3. S.F.Ai, G.Lu, Q.He, J.B.Li, J.Am.Chem.Soc.125(2003) 11140.

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5. J.G. Huang, I. Ichinose, T. Kunitake, A. Nakao, Nano. Lett. 2 (2002) 669.

Claims (32)

1. An inorganic porous nanotube, comprising a porous nanotube formed by metal oxide or metal sulfide, wherein said metal oxide or metal sulfide is selected from: titanium dioxide, zinc oxide, zinc sulfide, manganese oxide, manganese sulfide , the pore diameter of the inorganic porous nanotube is between 1nm and 500nm. 2. The inorganic porous nanotube of claim 1, wherein the metal oxide is titanium dioxide. 3. The inorganic porous nanotube of claim 1, wherein the metal oxide is zinc oxide or manganese oxide. 4. The inorganic porous nanotube of claim 1, wherein the metal sulfide is zinc sulfide or manganese sulfide. 5. The inorganic porous nanotube according to any one of claims 1-4, wherein the specific surface area of the inorganic porous nanotube is 100-300 m ² /g, and the porosity is 2-7 nm. 6. The inorganic porous nanotube according to claim 5, wherein the specific surface area of the inorganic porous nanotube is 103 m ² /g, and the porosity is 2-5 nm. 7. The preparation method of the inorganic porous nanotube according to any one of claims 1 to 6, wherein the inorganic porous nanotube is formed by the following steps: First, the template with microscopic porous morphology is placed into the solution of the compound with the first group, the compound with the first group is selected from the inorganic acid salt of the transition metal, the organic acid salt of the transition metal, or the compound with the alkane Oxygen metal salts; Then take out the template and put it into water or aqueous solution for hydrolysis; Then put the hydrolyzed template into the solution of the compound or biomolecule with the second group, and form a bond with the compound or biomolecule with the second group , and the compound with the second group or biomolecule The compound or biomolecule is selected from compounds or biomolecules having formable chemical bonds; Finally, the compound or biomolecule with the second group is removed. 8. The preparation method of inorganic porous nanotubes according to claim 7, wherein the chemical bonds are hydrogen bonds. 9. The preparation method of inorganic porous nanotubes according to claim 7, wherein; The compound having the first group can be hydrolyzed into transition metal oxide or transition metal sulfide; The compound with the first group is distinct from the compound or biomolecule with the second group, and the compound or biomolecule with the second group is readily removable. 9. The preparation method of the inorganic porous nanotube according to claim 7, wherein the compound having the first group is selected from a metal compound having an alkoxy group, a metal compound having an acyl chloride or an acid anhydride group, and the Compounds with a first group are capable of hydrolysis to the corresponding metal oxide or sulfide. 10. The preparation method of inorganic porous nanotubes according to claim 7, wherein the compound having the first group is selected from titanium alkoxide, titanium inorganic acid, zinc organic acid, manganese organic acid. 11. The preparation method of inorganic porous nanotubes according to claim 7, wherein the compound having the first group is selected from Ti(OBu) ₄ , TiCl ₄ , Zn(OAC) ₂ , Mn(OAC) ₂ . 12. The preparation method of inorganic porous nanotubes according to claim 7, wherein the template with microscopic porous morphology is selected from aluminum oxide film and polycarbonate film. 13. The preparation method of inorganic porous nanotubes according to claim 12, wherein the template with a microscopic porous morphology is selected from an aluminum oxide film or a polyester film with a pore diameter of 20 to 500 nanometers and a diameter of 1 to 5 centimeters . 14. The method for preparing inorganic porous nanotubes according to claim 13, wherein the template with microscopic porous morphology is an aluminum oxide film. 15. The preparation method of the inorganic porous nanotube according to any one of claims 1-6, comprising the following steps: a. Putting the template with the microporous morphology into the anhydrous solvent solution dissolved with the compound having the first group for a period of time; b. taking out the template and putting it into water for a period of time to hydrolyze the compound with the first group to generate an inorganic compound; c. Putting the template into a solution of a compound having a second group or a biomolecule prepared in an anhydrous solvent for a period of time; e. placing the template in high temperature or other environment that can dissolve the second group compound or biomolecule, and remove the compound or biomolecule with the second group to form the compound with the first group Inorganic porous nanotubes formed by the hydrolysis of the compound. Wherein, the compound having the first group is selected from inorganic acid salts of transition metals and organic acid salts of transition metals, provided that the inorganic acid salts of transition metals and organic acid salts of transition metals can be hydrolyzed into transition metal oxides compounds or transition metal sulfides; And the compound or biomolecule having the second group is selected from compounds or biomolecules having a chemical bond; The proviso is that the compound with the first group is different from the compound or biomolecule with the second group and that the compound or biomolecule with the second group is easy to remove. 16. The preparation method according to claim 15, wherein the chemical bond is a hydrogen bond. 17. The preparation method according to claim 15, further comprising the steps of: d. Repeat steps a, b, and c multiple times in order to obtain the corresponding number of layers, which can ensure that after the compound or biomolecule with the second group is removed, it will be generated by the hydrolysis of the compound of the first group Stable Presence of Inorganic Compounds in Porous Nanotubes. 18. The preparation method according to claim 15, wherein the compound with the first group is selected from transition metal inorganic acid salts, transition metal organic acid salts, or metal compounds with alkoxy groups, and the compound with the second group A group of compounds can be hydrolyzed to the corresponding transition metal oxide or sulfide. 19. The preparation method according to claim 15, wherein the compound or biomolecule having the second group is selected from polyacrylic acid, polystyrenesulfonic acid, polyvinylamine. 20. The preparation method according to claim 15, wherein the template is selected from the group consisting of alumina template and polycarbonate template. 21. The preparation method according to claim 19, wherein the concentration of the polyacrylic acid is between 0.01% and 10% of the mass of the solute to the volume of the solvent, wherein the unit of the mass of the solute is gram, and the unit of the volume of the solvent is is milliliters. 22. The preparation method according to claim 19, wherein the concentration of the polyacrylic acid is that the percentage of the mass of the solute to the volume of the solvent is between 1% and 10%, wherein the unit of the mass of the solute is grams, The unit of the solvent volume is milliliter. 23. The preparation method according to claim 18, wherein the compound having the first group is selected from titanium alkoxide, titanium inorganic acid, zinc organic acid, manganese organic acid. 24. The preparation method according to claim 15, wherein the compound having the first group is selected from Ti(OBu) ₄ , TiCl ₄ , Zn(OAC) ₂ , Mn(OAC) ₂ . 25. The preparation method according to claim 23, wherein the concentration of the titanium alkoxide or the titanium inorganic acid is between 0.1% and 10% of the mass of the solute to the volume of the solvent, wherein the unit of the mass of the solute is grams, The unit of the solvent volume is milliliter. 26. The preparation method according to claim 23, wherein the concentration of the titanium alkoxide or titanium inorganic acid is between 1% and 10% of the mass of the solute to the volume of the solvent, wherein the unit of the mass of the solute is grams, The unit of the solvent volume is milliliter. 27. The preparation method according to claim 15, wherein the step e is burning at a high temperature in a muffle furnace for a period of time to remove the compound or biomolecule with the second group from the template. 28. The preparation method according to claim 17, wherein said step d repeats step a, step b and step c 10-30 times sequentially in order to ensure sufficient adsorption time. 29. The preparation method according to claim 15 or 17, further comprising the steps of: f. Preparation of scanning samples: put the template in 1-6M NaOH aqueous solution for 30 minutes to 2 hours, remove the NaOH solution, rinse with water and ethanol, and place the template in ethanol for ultrasonic dispersion ,stand-by. 30. The preparation method according to claim 15 or 17, further comprising the steps of: g. Preparation of transmission electron microscope samples: put the template into 1-6M NaOH aqueous solution for 30 minutes to 2 hours, remove the NaOH solution, rinse with water and ethanol, and dialyze with water for 24-48 hours, after ultrasonic treatment The solution was dropped on the support film copper grid, and the transmission experiment was done after drying. 31. The preparation method according to claim 15 or 17, wherein the hydrolysis is a one-step hydrolysis. 32. The preparation method according to claim 15 or 17, wherein the hydrolysis is a multi-step hydrolysis.

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