KR101130666B1 - A Preparing Method for Mesoporous Silica Nanotube Using Glycylalkylamide - Google Patents

Abstract

The present invention relates to a method for producing silica nanotubes using glycylalkylamide as a template. 1) heating and dissolving glycylC ₆ -C ₁₆ alkylamide used as a template in an aqueous alcohol solution; 2) maintaining the alcohol aqueous solution at a constant temperature; 3) adding an inorganic silica precursor to the aqueous alcohol solution, heating and standing still; and 4) providing a method for producing silica nanotubes comprising washing with alcohol holes.

Using glycylalkylamide, a peptide surfactant, as a template through self-assembly of surfactants at room temperature or below 4 ℃, the channel length of the pore is 0.1-1000μm and the pore size is 2-4nm (SNT-1). , Silica nanotubes of 30-50nm (SNT-2). This method exhibits higher alignment and higher silica crystallinity compared to conventional silica nanotubes.

Nanotubes, Silicas, Glycyldodecylamides

Description

A preparing method for mesoporous silica nanotube using glycylalkylamide}

The present invention relates to a method for preparing silica nanotubes using glycylalkylamide, which has a peptide structure and a surfactant, as a template. In particular, the present invention relates to a method for producing silica nanotubes having different pore sizes according to temperature control through differences in self-assembly depending on the temperature of the peptide surfactant.

Nanometer-sized inorganic compound tubes are widely studied in the field of nanotechnology due to their potential use. Silica nanotubes can be used as a matrix for the synthesis of nanostructures of various materials, including electronic materials such as sensors, removal of harmful substances, and energy conversion catalyst carriers. In fact, dispersing nanometer-sized silica particles in a polymer material can produce a lighter and high-strength bumper, and dispersing nano-devices in tires can reduce wear of the polymer material, and the braking distance due to the characteristics of the nano protrusions Can be reduced.

Since the discovery of a method for synthesizing nanoporous silica by micelle formation of surfactants, there have been many reports on applications in the chemical, life science, optical and electrical industries. In particular, the inorganic compound of the one-dimensional structure is currently being studied a lot because of the useful properties such as molecular sensor, compound separation, chromatography, adsorbent, catalyst and light emission, as well as application to functional devices. In particular, the sol-gel template method (SGTM) is most commonly used to make a wide range of nano-sized inorganic compounds having a one-dimensional structure, and the ion between the appropriate cation site and the adsorption anion inorganic material of the organic molecular assembly. It is produced by the bonding or hydrogen bonding action.

Conventionally, a fibrous or hollow inorganic material, a molecular association of tartaric acid, carbon fibers, and carbon nanotubes were synthesized.

Dong et al. (W. Dong, W. Li, K. Yu, K. Krishna, L. Wang, X. Song, Z. Wang, M.-O. Coppens, S. Feng, Chem. Comm . 2003) Silica nanotubes were prepared using kaolin clay nanocrystals as templates. A nanotube having a pore size of about 100 nm was obtained. Yang et al. (R. Fan, Y. Wu, D. Li, M. Yue, A. Majumdar, P. Yang, J. Am. Chem. Soc . 2003 , 125 , 5254-5255) using silicon nanowires as templates. An attempt was made to synthesize one nanotube. Xiao et al. (Q.-G. Xiao, X. Tao, J.-F. Chen, Ind. Eng. Chem. Res. 2007 , 46 , 459-463) silica nanotubes were prepared using calcium carbonate nanosticks as templates. Murphy et al. (SO Obare R. Jana, C. J Murphy, Nano Lett. 2001 , 1 , 601-603) prepared silica nanotubes standardized using gold nanorods as templates. However, this method is also very expensive and difficult to recover gold. Zygmunt et al. (J. Zygmunt, F. Krumeich, R. Nesper, Adv. Mater. 2003 , 15 , 1538-1541) attempted to synthesize silica nanotubes using a template using vanadium oxide (V ₂ O ₇ ). . This method also has the disadvantage of being extremely expensive and a problem that the tube size is very large, reaching 800 nm. Therefore, the casting method using the above five inorganic materials has the weak point that the crystal structure is weak and the cost is very high.

In addition, there has been an attempt to manufacture various types of inorganic materials by using biological materials as a template (Japanese Patent Laid-Open No. 2000-220036), and a cylindrical organic inorganic composite using a self-assembled fat tube. Was prepared. In addition, Japanese Laid-Open Patent Publication No. 2001-335594 relates to a technique for producing an organic-inorganic composite and a metal oxide using a cholesterol derivative having a hydrogen bonding site as a template, to prepare a metal oxide in a cylindrical or roll paper form. It was. As described above, the present invention relates to a technique for preparing a metal oxide by using a technique in which a metal oxide polymer is formed while a sol such as an organic molecule and a metal alkoxide are polymerized and crosslinked by a catalyst, It is difficult to control the composite or metal oxide to a uniform shape because it is manufactured in a fiber shape or a spiral in which a hollow is formed.

As a method of synthesizing representative organic template in aqueous solution, the Pouget group (E. Pouget, E. Dujardin, A. Cavalier, A. Moreac, C. Valry, V. Marchi-Artzner, T. Weiss, A. Renault, M. Paternostre, F. Artzner, Nat. Mater. 2007 , 6 , 435-439.) Silica nanotubes were synthesized via cyclic lanreotide. However, this method has the disadvantage of being very expensive. Hartingrink et al. (VMJ Yuwono, D. Hartgerink, Langmuir 2007 , 23 , 5033-5038.) Have successfully fabricated nanotubes using PAt (Peptide Amphiphiles). However, this method is also very expensive, difficult to put to practical use, and the size of the tube is not as large as 4 nm. Zollfrank et al. ( C. Zollfrank, H. Scheel, P. Greil, Adv. Mater . 2007 , 19 , 984-987) synthesized glucoseamine (glucoseamine) to prepare a nanotube using the same. This method has a problem that the pores are blocked, the synthesis is not easy. The tube size is not as big as about 3nm.

An object of the present invention is to provide a method for producing silica nanotubes by the sol-gel casting method using a peptide surfactant.

The present inventors have provided a method for preparing silica nanotubes by cocondensing tetraethoxyorthosilicate (TEOS) on a solution of an organic sol system based on a peptide surfactant.

The present invention comprises the steps of: 1) heat-dissolving glycylC ₆ -C ₁₆ alkylamide used as a template in an aqueous alcohol solution; 2) maintaining the alcohol aqueous solution at a constant temperature; 3) adding the inorganic silica precursor to the aqueous solution of the inorganic silica precursor / glycyl C ₆ -C ₁₆ alkylamide in the range of 4 ~ 10 inorganic silica precursor, heating and standing; and 4) washing with alcohol It provides a method for producing silica nanotubes.

In the above steps 1) and 2), a tubular mold is prepared using a peptide amphiphilic compound comprising a peptide and an amine group, and a modified self-assembled tube form of the peptide amphiphilic compound is prepared using a change in temperature. Step 3) is co-condensation at room temperature, hydrothermal or microwave irradiation environment. By using step 3), a copolymer of a peptide amphiphilic compound and an inorganic silica precursor such as tetraethoxy orthosilicate is prepared in the solution, and the internal template formed of the peptide amphiphilic compound is removed by step 4). .

The glycylC ₆ -C ₁₆ alkylamide is preferably glycyldodecylamide and the alcohol is ethanol and the inorganic silica precursor is preferably tetraalkoxyethoxyorthosilicate, most preferably tetraethoxyorso Silicate.

 Keeping at room temperature in step 2) to prepare a silica nanotube having a pore size of 1-5 nm, preferably 2-4 nm. If it is maintained at 0 ~ 5 ℃, preferably approximately 2 ℃ in step 2) to prepare a silica nanotube having a pore size of 20-50nm, preferably 40-50nm. In the present specification, "SNT-1" refers to "silica nanotubes having pore sizes of several nanometers" and "SNT-2" refers to "silica nanotubes having pore sizes of several tens of nanometers".

By utilizing the difference in the self-assembly of the peptide surfactant of the present invention by the temperature control it was possible to provide two kinds of silica nanotubes at the same time. In the present invention, the synthesis of the silica structure under neutral conditions and room temperature is very important in terms of environmental and energy saving in the direct synthesis of the material, and it is also economical that a relatively expensive surfactant can be easily recovered and used as an organic solvent. There are many environmental benefits.

Preferred embodiments of the present invention will be described by way of example in FIG. 1, the present invention being explained in more detail in the following Examples. However, these Examples are only illustrative description of the present invention and the scope of the present invention is not limited to these Examples.

Example  1: silica nanotubes ( SNT -1) manufacturing

1 mmol of the compound of Formula 1 was used as a gel-generator, 20 ml of water and 2 ml of ethanol were added thereto, and the solution was heated at 60 ° C. until the solution became clear, and further 4 mmol of TEOS (tetraethoxyorthosilicate) was added thereto. The solution was heated again until it became clear, and it was stored for 3 days at room temperature and static conditions. Finally, compound 1 was recovered using ethanol to prepare silica nanotubes (silica nanotube-1, SNT-1).

Crystals were analyzed by TEM. The image of FIG. 2 shows that the silica nanotubes have an outer diameter of 10-30 nm and an inner diameter of 2-3 nm. It was a crystalline outer wall and a long channel nanotube. Nitrogen adsorption analysis was performed by Barrett, Joyner and Halenda method. The BET surface area was 685 m ² / g, the pore volume was 0.85 cm ³ / g, and the pore size was 2.8 nm.

Example  2: silica nanotubes ( SNT -2) manufacturing

Using the same compound as the above compound of Formula 1 as a gel-generator 1mmol, 20ml of water and 2ml of ethanol were added and heated at 60 ℃ until the solution becomes clear, and then at 2 ℃ Keep stirring for 1 hour. 4 mmols of TEOS (tetraethoxysilane) were further added thereto, and the mixture was stirred vigorously for 1 hour, and stored at room temperature and static condition for 3 days. Finally, compound 1 was recovered using ethanol to prepare silica nanotubes (silica naotube-2, SNT-2).

Crystals were analyzed by TEM. The image of FIG. 2 shows that the silica nanotubes have an outer diameter of 70-80 nm and an inner diameter of 40-50 nm. It is a crystalline outer wall and a long channel type nanotube. Nitrogen adsorption analysis was performed by Barrett, Joyner and Halenda method. The BET surface area was 395 m ² / g, the pore volume was 1.12 cm ³ / g, and the pore size was 45 nm.

1 is illustrated for the nanotube manufacturing process of the present invention

2 and 4 are SEM and TEM images of a long channel silica nanotube having a pore size of 2-4 nm according to Example 1 of the present invention.

3 and 5 are SEM and TEM images of long channel silica nanotubes having a pore size of 40-50 nm according to Example 2 of the present invention.

Claims (4)

delete delete 1) heat-dissolving glycylC ₆ -C ₁₆ alkylamide used as a template in an aqueous alcohol solution; 2) maintaining the aqueous alcohol solution at room temperature; 3) adding the inorganic silica precursor to the aqueous solution of the inorganic silica precursor / glycyl C ₆ -C ₁₆ alkylamide in the range of 4 ~ 10, and heating and then standing still; and 4) washing with alcohol Method for producing silica nanotubes having a pore size of 1-5 nm 1) heat-dissolving glycylC ₆ -C ₁₆ alkylamide used as a template in an aqueous alcohol solution; 2) maintaining the alcohol aqueous solution at 0 ~ 5 ℃; 3) adding the inorganic silica precursor to the aqueous solution of the inorganic silica precursor / glycyl C ₆ -C ₁₆ alkylamide in the range of 4 ~ 10, and heating and then standing still; and 4) washing with alcohol Method for producing silica nanotubes having a pore size of 20-50 nm

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