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WO2009096569A1 - Procédé pour produire un nanomatériau métallique et nanomatériau métallique obtenu par celui-ci - Google Patents

Procédé pour produire un nanomatériau métallique et nanomatériau métallique obtenu par celui-ci Download PDF

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Publication number
WO2009096569A1
WO2009096569A1 PCT/JP2009/051665 JP2009051665W WO2009096569A1 WO 2009096569 A1 WO2009096569 A1 WO 2009096569A1 JP 2009051665 W JP2009051665 W JP 2009051665W WO 2009096569 A1 WO2009096569 A1 WO 2009096569A1
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Prior art keywords
silver
gold
silver shell
gold nanorods
shell
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English (en)
Japanese (ja)
Inventor
Yasuro Niidome
Koji Nishioka
Yoshifumi Okuno
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Kyushu University NUC
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Kyushu University NUC
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Priority to JP2009551629A priority Critical patent/JP5327877B2/ja
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/16—Making metallic powder or suspensions thereof using chemical processes
    • B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
    • B22F9/24—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from liquid metal compounds, e.g. solutions
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/05—Metallic powder characterised by the size or surface area of the particles
    • B22F1/054—Nanosized particles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/05—Metallic powder characterised by the size or surface area of the particles
    • B22F1/054—Nanosized particles
    • B22F1/0553—Complex form nanoparticles, e.g. prism, pyramid, octahedron
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/05—Metallic powder characterised by the size or surface area of the particles
    • B22F1/054—Nanosized particles
    • B22F1/056—Submicron particles having a size above 100 nm up to 300 nm
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/17—Metallic particles coated with metal
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites

Definitions

  • the present invention relates to a method for producing a metal nanomaterial and a metal nanomaterial obtained thereby. More specifically, the present invention relates to a method for producing a metal nanomaterial having a core-shell structure having a core made of gold nanoparticles and a shell made of silver (hereinafter sometimes abbreviated as “silver shell gold nanoparticles”), and The metal nanomaterial obtained thereby.
  • Metal nanomaterials for example, metal nanoparticles, unlike bulk metals, exhibit unique optical properties derived from their surface plasmons.
  • the optical characteristics vary depending on the particle size and shape of the particles. Therefore, control of the particle size and shape of the metal nanoparticles is extremely important. However, control of particle size and shape is generally difficult.
  • spherical gold nanoparticles have a surface plasmon band in the visible region (520 nm) and a large particle size. It has high light absorption and high light scattering properties (Non-patent Documents 1 and 2). It is known that gold nanoparticles having a relatively large particle size can be produced by controlling the particle size and shape by a citric acid reduction method (Non-Patent Documents 1 to 3).
  • nanoparticles having a large particle size are prepared by a seed method using hexadecyltrimethylammonium bromide (CTAB), which is considered to contribute greatly to crystal controllability and dispersion stability of the particles, as a protective agent.
  • CTAB hexadecyltrimethylammonium bromide
  • gold nanorods which are rod-shaped gold nanoparticles, have a surface plasmon band derived from the long axis in the near infrared region.
  • CTAB crystal anisotropically
  • the spherical silver nanoparticles have a surface plasmon band in the visible range (390 nm).
  • a method for producing silver nanoparticles there is a polyol method using polyvinylpyrrolidone as a template (Non-Patent Document 8).
  • the shape of silver nanoparticles (sphere, nanocube, triangular nanoplate, nanorod, nanodisk, etc.) ) has been reported to be controllable (Non-Patent Documents 9 to 11).
  • the shell generation process can be controlled in addition to the control of the core shape. For this reason, it is possible to produce metal nanomaterials of more various sizes and shapes uniformly and realize a wide range of spectral characteristics. From this point, a metal nanomaterial having a core-shell structure is expected to exhibit optical properties superior to those of a single composition metal nanomaterial.
  • a metal nanomaterial for example, a metal nanomaterial having a core made of spherical gold nanoparticles and a shell made of silver (Non-Patent Documents 12 to 20; hereinafter, abbreviated as “silver shell gold nanoparticles”)
  • Non-Patent Documents 12 to 20 hereinafter, abbreviated as “silver shell gold nanoparticles”
  • metal nanomaterials 21 to 28 reports of metal nanomaterials having a core made of gold nanorods and a shell made of silver.
  • spherical gold nanoparticles can be obtained from the point that anisotropic particles having a large particle diameter that have not been obtained can be obtained in a uniform shape. It is more advantageous than the case where is used.
  • Non-patent documents 21 to 28 describe a method for producing a metal nanomaterial having a core-shell structure having a core made of gold nanorods and a shell made of silver, in which silver ions are present in the presence of CTAB as a protective agent.
  • a silver shell is formed on the surface of the gold nanorod as a core by reduction.
  • none of these manufacturing methods is practical because of poor reproducibility and controllability of the thickness of the shell formed. Accordingly, there is a demand for a method capable of producing a metal nanomaterial having a uniform core-shell structure with good reproducibility.
  • the object of the present invention is to form a shell made of silver covering the entire surface of the gold nanoparticle as a core with good controllability. Therefore, a metal nanomaterial having a uniform core-shell structure is reproducible. It is to provide a method that can be manufactured well.
  • the present inventors have found that, in reducing silver ions using a reducing agent in an aqueous dispersion of gold nanoparticles, chloride ions are added to the aqueous dispersion.
  • chloride ions are added to the aqueous dispersion.
  • the entire surface of the gold nanoparticle can be coated with silver with good controllability, that is, the shell made of silver can be formed with good controllability covering the entire surface of the core gold nanoparticle.
  • the present inventors have found that this can be done and have completed the present invention.
  • the present invention is as follows.
  • a silver ion is reduced by adding a reducing agent to an aqueous dispersion of gold nanoparticles containing chloride ions and then adding an inorganic silver salt dispersed in an aqueous solution containing chloride ions.
  • the manufacturing method as described in said (1) which has a process.
  • the gold nanoparticles are spherical gold nanoparticles and the diameter thereof is 2 to 100 nm.
  • the production method according to any one of (1) to (4) above, wherein the temperature at which the reduction is performed is 15 ° C. to 100 ° C.
  • the counter ion of chloride ion is selected from the group consisting of sodium ion, potassium ion, calcium ion, magnesium ion, hexadecyltrimethylammonium ion and heptadecyltrimethylammonium ion (1) to (10) The manufacturing method as described in any one of these.
  • the gold nanoparticle is a spherical gold nanoparticle and has a diameter of 2 to 100 nm.
  • the shell made of silver can be formed with good controllability covering the entire surface of the gold nanoparticle serving as the core, and thus the core-shell structured metal nanomaterial having a uniform shape. Can be manufactured with good reproducibility.
  • the metal nanomaterial obtained by the production method of the present invention has excellent optical properties (for example, high light absorption, high light scattering, etc.). In particular, by having a high light scattering property, it can be used for observation of cell dynamics, application as a sensor particle for an immunoaffinity graph, and the like.
  • FIG. 1 is a view showing a TEM photograph of silver shell gold nanorods produced in Example 1.
  • FIG. 2 is a diagram showing a TEM photograph of the silver shell gold nanorods produced in Example 2.
  • FIG. 3 is a view showing a TEM photograph of the silver shell gold nanorods produced in Example 3.
  • 4 is a view showing a TEM photograph of the silver shell gold nanorods produced in Example 4.
  • FIG. 5 is a view showing a TEM photograph of the silver shell gold nanorods produced in Example 5.
  • 6 is a diagram showing a TEM photograph of the silver shell gold nanorods produced in Example 6.
  • FIG. 7 is a view showing a TEM photograph of the silver shell gold nanorod prepared in Example 7.
  • FIG. 8 is a view showing a TEM photograph of the silver shell gold nanorods produced in Example 8.
  • FIG. 9 is a view showing a TEM photograph of the silver shell gold nanorods produced in Example 9.
  • FIG. 10 is a view showing a TEM photograph of the silver shell gold nanorods produced in Example 10.
  • FIG. 11 is a view showing a TEM photograph of the silver shell gold nanorods produced in Example 11.
  • FIG. 12 is a view showing a TEM photograph of the silver shell gold nanorods produced in Example 12.
  • 13 is a view showing a TEM photograph of the silver shell gold nanorods produced in Example 13.
  • FIG. FIG. 14 is a view showing a TEM photograph of silver shell gold nanorods produced in Example 14.
  • FIG. 14 is a view showing a TEM photograph of silver shell gold nanorods produced in Example 14.
  • FIG. 15 is a view showing a TEM photograph of the silver shell gold nanorods produced in Example 15.
  • 16 is a view showing a TEM photograph of the silver shell gold nanorods produced in Example 16.
  • FIG. 17 is a view showing a TEM photograph of the silver shell gold nanorods produced in Example 17.
  • FIG. 18 is a diagram showing a TEM photograph of the silver shell gold nanorods produced in Comparative Example 1.
  • FIG. 19 is a diagram showing the scattering spectrum of the silver shell gold nanorods produced in Example 18 and the gold nanorods forming the core.
  • 20 is a view showing a TEM photograph of a gold-silver shell gold nanorod produced in Example 19.
  • FIG. 21 is a view showing a TEM photograph of silver shell gold nanoparticles prepared in Example 20.
  • FIG. 22 is a view showing a TEM photograph of gold-silver shell gold nanoparticles prepared in Example 21.
  • FIG. 23 is a view showing a TEM photograph of the silver shell gold nanorods produced in Example 22.
  • FIG. 24 is a view showing a TEM photograph of the silver shell gold nanorods produced in Example 23.
  • FIG. 25 is a view showing a TEM photograph of the silver shell gold nanorods produced in Example 24.
  • FIG. FIG. 26 shows the absorption spectrum of the silver shell gold nanorods produced in Examples 24 and 25.
  • FIG. 27 (A), (B) and (C) show the TEM of the silver shell gold nanorods prepared in Example 25 (when the added amount of the AgNO 3 aqueous solution is 0.13 mL, 0.38 mL and 0.50 mL, respectively). It is a figure which shows a photograph.
  • FIG. 28 is a graph showing absorption spectra of the silver shell gold nanorods produced in Examples 24 and 26.
  • FIGS. 29A and 29B are TEM photographs of the silver shell gold nanorods produced in Example 26 (when the reduction reaction temperatures are 50 ° C. and 70 ° C., respectively).
  • FIG. 30 is a diagram showing an absorption spectrum of the silver-shell gold nanorods produced in Example 27.
  • FIG. 31 (A), (B), (C), (D) and (E) show the silver shell gold nanorods prepared in Example 27 (reduction reaction times of 5 minutes, 10 minutes, 30 minutes and 90 minutes, respectively). It is a figure which shows the TEM photograph of 150 minutes.
  • 32 is a view showing a TEM photograph of the silver shell gold nanorods produced in Example 28.
  • FIG. 33 is a view showing a TEM photograph of silver shell gold nanorods produced in Example 29.
  • FIG. FIG. 34 is a diagram showing absorption spectra of gold nanoparticles and silver shell gold nanoparticles prepared in Example 30.
  • FIG. FIG. 35 is a view showing a TEM photograph of gold nanoparticles prepared in Example 30.
  • FIG. 36 is a view showing a TEM photograph of silver shell gold nanoparticles prepared in Example 30.
  • FIG. FIG. 37 is a graph showing an absorption spectrum of the silver shell gold nanorods produced in Example 31.
  • 38 (A), (B), (C), (D) and (E) show the silver shell gold nanorods prepared in Example 31 (the addition amounts of CTAC-dispersed gold nanorods were 0.2 mL and 0.4 mL, respectively). , 0.8 mL, 1.2 mL and 1.6 mL)).
  • FIG. 39 is a view showing a TEM photograph of silver shell gold nanorods produced in Example 32.
  • FIG. 40 is a view showing a TEM photograph of silver shell gold nanorods produced in Example 33.
  • the present invention is described in detail below.
  • the method of producing a metal nanomaterial having a core-shell structure having a core made of gold nanoparticles and a shell made of silver according to the present invention is reduced in an aqueous dispersion of gold nanoparticles containing an inorganic silver salt and chloride ions.
  • a step of reducing silver ions using an agent comprises adding a reducing agent to an aqueous dispersion of gold nanoparticles containing chloride ions, and then dispersing the inorganic silver in an aqueous solution containing chloride ions.
  • the gold nanoparticles used in the production method of the present invention include rod-shaped gold nanoparticles (gold nanorods), spherical gold nanoparticles (gold nanoparticles), and the like.
  • gold nanorod refers to nanoscale rod-shaped gold nanoparticles having an aspect ratio (ratio of the length in the major axis direction to the length in the minor axis direction) greater than 1.
  • the gold nanorod suitably used in the production method of the present invention has a length in the major axis direction of 30 nm to 400 nm, and preferably 50 nm to 200 nm, more preferably 80 nm, from the viewpoint of dispersion stability and shape uniformity.
  • the length in the minor axis direction is 3 nm to 50 nm, and from the viewpoint of dispersion stability and shape uniformity, preferably 5 nm to 40 nm, more preferably 10 nm to 20 nm, and the aspect ratio is the shape From the viewpoint of uniformity, it is preferably 2 to 20, more preferably 4 to 8.
  • the gold nanoparticles suitably used in the production method of the present invention preferably have a diameter of 2 to 100 nm, more preferably 20 to 80 nm, from the viewpoint of dispersion stability and shape uniformity.
  • gold nanorods and gold nanoparticles commercially available products may be used, or methods known per se (for example, gold nanorods disclosed in JP-A-2004-292627, JP-A-2005-97718, JP-A-2006). -Methods described in JP-A No. 169544, JP-A 2006-118036, etc .; gold nanoparticles can be synthesized according to the methods described in Non-Patent Document 1, Non-Patent Document 2, Non-Patent Document 3, and the like.
  • gold nanorods are prepared by, for example, using gold ions (as a gold ion source, for example, gold chloride) in an aqueous solution containing quaternary ammonium salt hexadecyltrimethylammonium bromide (CTAB) as a cationic surfactant. It is possible to synthesize it by reducing a halogenated gold acid such as an acid) by chemical reduction, electroreduction, photoreduction or the like. The synthesized gold nanorods are stably dispersed in water due to the protective action of CTAB.
  • the gold nanoparticles can be synthesized, for example, by chemically reducing gold ions in an aqueous solution containing citric acid. The synthesized gold nanoparticles are stably dispersed in water due to the protective action of citric acid.
  • the inorganic silver salt examples include silver nitrate, silver cyanide and silver acetate, and silver nitrate is preferable from the viewpoint of availability, chemical stability and toxicity.
  • the inorganic silver salt is usually added in an amount of 0.1 to 10 ml of an aqueous solution having a concentration of 0.1 mM to 50 mM to 0.8 ml of a gold nanoparticle dispersion having a gold atom concentration of 0.001 wt% to 0.1 wt%.
  • 0.25 to 10 ml of an aqueous solution having a concentration of 8 mM to 12 mM is added to 0.8 ml of a gold nanoparticle dispersion having a gold atom concentration of 0.02 wt% to 0.04 wt%. If the amount used is, for example, less than 0.1 ml in an aqueous solution with a concentration of 3 mM, the entire surface of the gold nanoparticles may not be coated with silver.
  • a base may be further added to the reduction reaction system.
  • the base that can be used in the production method of the present invention is preferably a hydroxide, more preferably a strong base such as sodium hydroxide or potassium hydroxide, from the viewpoint of reproducibility, availability, and price.
  • Sodium hydroxide is particularly preferred.
  • the amount of the base used is usually 0.05 to 1 ml in an aqueous solution having a concentration of 400 mM to 600 mM with respect to 0.8 ml of the above gold nanoparticle dispersion (gold atom concentration of 0.001 wt% to 0.1 wt%).
  • it is 0.1 to 1 ml in an aqueous solution having a concentration of 500 mM.
  • the amount used is, for example, less than 0.05 ml in an aqueous solution having a concentration of 500 mM, it is difficult to obtain silver shell gold nanoparticles having a uniform shape.
  • the reducing agent examples include ascorbic acid, citric acid, sodium thiocyanate, etc., and ascorbic acid from the viewpoint of excellent controllability of the reduction reaction and a slow generation rate of silver nuclei on the gold nanoparticle surface.
  • the amount of the reducing agent used is usually 0.01 to 10 ml of an aqueous solution having a concentration of 50 mM to 150 mM, preferably 0.8 ml to the above gold nanoparticle dispersion (gold atom concentration of 0.001 wt% to 0.1 wt%). Is 0.05 to 5 ml in a 100 mM aqueous solution.
  • the amount used is, for example, less than 0.01 ml in an aqueous solution with a concentration of 100 mM, all silver ions in the aqueous dispersion may not be reduced, and gold nanoparticles may not be uniformly coated with silver. The shape of the silver shell gold nanoparticles may not be uniform.
  • the amount of chloride ion used is usually 1 to 100 ml in an aqueous solution with a concentration of 50 mM to 150 mM, preferably 0.8 to 100 ml with respect to 0.8 ml of the gold nanoparticle dispersion (0.001 wt% to 0.1 wt% in terms of gold atom concentration), preferably The concentration is 10 to 50 ml with an aqueous solution of 80 mM. If the amount used is, for example, less than 1 ml in an aqueous solution having a concentration of 80 mM, the shape of the silver shell gold nanoparticles may not be uniform.
  • chloride ion counter cations include inorganic or organic cations, preferably inorganic ions such as sodium ion, potassium ion, calcium ion, magnesium ion, hexadecyltrimethylammonium ion, heptadecyltrimethylammonium ion, and the like. Selected from the group consisting of quaternary ammonium ions. Of these, hexadecyltrimethylammonium ion is preferable.
  • the temperature at which the reduction is carried out is usually 15 ° C. to 100 ° C., preferably 20 ° C. to 70 ° C., more preferably 30 ° C. to 40 ° C. If the temperature is lower than 15 ° C. or higher than 100 ° C., silver shell gold nanoparticles having a uniform shape may not be obtained.
  • the time for reduction is usually 0.1 to 10 hours, although it depends on the reduction reaction temperature.
  • Specific operation procedures for carrying out the reduction step include, for example, the following procedures. First, gold nanoparticles are dispersed in an aqueous solution containing chloride ions to prepare an aqueous dispersion of gold nanoparticles. Next, an inorganic silver salt (preferably in the form of an aqueous solution) and a reducing agent (preferably in the form of an aqueous solution) are added to the aqueous dispersion. Furthermore, a base (preferably in the form of an aqueous solution) is added to this aqueous dispersion as necessary to initiate the reduction reaction. Alternatively, gold nanoparticles are dispersed in an aqueous solution containing chloride ions to prepare an aqueous dispersion of gold nanoparticles.
  • a reducing agent preferably in the form of an aqueous solution
  • an inorganic silver salt preferably in the form of an aqueous solution
  • an aqueous solution containing chloride ions and a base preferably in the form of an aqueous solution
  • the shell made of silver can be formed with good controllability by covering the entire surface of the gold nanoparticle as the core by the above reduction step.
  • the thickness of the shell formed depends on the silver ion concentration in the aqueous dispersion of gold nanoparticles, the aspect ratio of the gold nanorods, the diameter of the gold nanoparticles, the temperature at which the reduction is performed, etc. In this case, it is usually 1 nm to 50 nm in the major axis direction and 1 nm to 100 nm in the minor axis direction.
  • the core is gold nanoparticles, it is usually 1 nm to 100 nm.
  • the unreacted nanoparticles consisting only of gold and the by-products consisting only of silver are separated, and the core consisting of gold nanoparticles It is possible to isolate only a metal nanomaterial having a core-shell structure having a silver shell.
  • the core-shell structure metal nanomaterial having the core made of the gold nanoparticles of the present invention and the shell made of silver of the present invention obtained as described above has a uniform shape, and the size is such that the core is a gold nanorod.
  • the length in the major axis direction is 30 nm to 100 nm
  • the length in the minor axis direction is 10 nm to 100 nm
  • the aspect ratio is 1 to 10
  • the core is gold nanoparticles
  • the diameter is usually Is 10 nm to 100 nm.
  • the metal nanomaterial having a core-shell structure having a core made of gold nanoparticles and a shell made of silver of the present invention has an absorption spectrum of 330 to 370 nm, 400 to 420 nm, 440 to 600 nm, and 510 to 850 nm, respectively. Has a disappearing peak.
  • a core made of gold nanoparticles A metal nanomaterial having a core-double shell structure (hereinafter, abbreviated as “gold-silver shell gold nanoparticle”) having a shell made of silver and a shell made of gold on the shell surface.
  • gold-silver shell gold nanoparticles are, for example, gold nanorods or gold nanoparticle synthesis methods (for example, gold nanorods disclosed in JP-A Nos. 2004-292627, 2005-97718, and 2006-169544).
  • a quaternary ammonium salt hexadecyltrimethylammonium bromide (CTAB), hexadecyltrimethylammonium chloride (CTAC), etc.
  • gold ions for example, chloride as a source of gold ions
  • Chemical reduction, electroreduction, light using halogenated gold acids such as gold acid
  • the gold-silver shell gold nanoparticles generated as described above are subjected to post-treatment such as centrifugation and gel filtration to separate unreacted silver shell gold nanoparticles and a by-product consisting of only gold, It can be isolated.
  • the metal nanomaterial of the present invention has excellent optical properties (for example, high light absorption, high light scattering, etc.).
  • the light scattering property can be evaluated by measuring the light scattering intensity.
  • the light scattering intensity can be measured according to the method described in the following examples.
  • the metal nanomaterial of the present invention is used not only for pigments and optical filters, but also for application to cell dynamics observation and sensor particles for immunoaffinity graphs because of its high light scattering property. Is possible. Moreover, application as a sensor material for surface-enhanced Raman scattering (SERS) spectroscopy can be expected.
  • SERS surface-enhanced Raman scattering
  • Measurement of light scattering intensity Measurement was performed with a multi-channel detector (PMA-12, manufactured by Hamamatsu Photonics Co., Ltd.) using a quartz cell having an optical path length of 1 cm (exposure time: 100 ms, integration count: 100 times). Since the output data also reflects the light intensity distribution of the light source of the halogen lamp, correction is made using a polystyrene aqueous solution that has almost no absorption in the visible region (400-800 nm), that is, all the disappearance components are scattering components. went.
  • the transmittance at each wavelength is obtained from the disappearance spectrum measurement, and by subtracting this from 1, the scattering rate at each wavelength (the ratio of the scattered light to the incident light) is obtained. Furthermore, since the output data from the multichannel detector is the product of the light intensity and the scattering rate of the light source at each wavelength, the light intensity of the light source at each wavelength can be obtained using this. Using the light intensity of this light source, the light scattering intensity of various scattering spectra was calculated.
  • a gold nanorod dispersion in an aqueous hexadecyltrimethylammonium chloride (CTAC) solution is abbreviated as a CTAC-dispersed gold nanorod.
  • CTAC-dispersed gold nanorods Gold nanorod dispersion in 480 mM hexadecyltrimethylammonium bromide (CTAB) aqueous solution (manufactured by Mitsubishi Materials) (gold atom concentration: 0.03 wt%, size of gold nanorods: length in short axis direction 9.7 nm, long axis direction (50.8 nm in length, aspect ratio 5.2) 10 mL was centrifuged at 8000 ⁇ g for 10 minutes to precipitate the gold nanorods.
  • CAB hexadecyltrimethylammonium bromide
  • the length of the gold nanorods in the long axis direction was 50.8 ⁇ 7 nm
  • the length in the short axis direction was 9.7 ⁇ 1 nm
  • the aspect ratio was 5.2 (of 108 gold nanorods Average value).
  • an absorption peak (surface plasmon band) derived from the long axis was observed around 450 nm. This is because the surface plasmon band of the silver shell gold nanorod is changed from that of the gold nanorod due to the silver shell formed on the gold nanorod surface.
  • the absorption spectrum of metal nanoparticles having a core-shell structure is mainly derived from shell plasmons, but the core plasmons are also slightly affected. Therefore, it is surmised that the absorption spectrum of the silver shell gold nanorods is different from the absorption spectrum of the silver nanoparticles.
  • FIGS. 1A and 1B In TEM observation (FIGS. 1A and 1B), a silver shell inferred to be a rectangular parallelepiped was observed around the gold nanorods. It can be clearly seen that the gold nanorods exist in the center due to the difference in electron beam transmittance between gold and silver.
  • the silver shell gold nanorods had a major axis length of 64.3 ⁇ 7 nm, a minor axis length of 34.0 ⁇ 3 nm, and an aspect ratio of 1.9 (a total of 259 silver shell gold nanorods). Average value).
  • the structure of the protective layer of CTAC is not as static as CTAB, and the collision frequency of silver ions to the gold nanorod surface is high, so that reaction conditions suitable for the formation of a uniform silver shell can be obtained.
  • the Raman scattering spectrum was measured for the silver shell gold nanorods obtained above.
  • a small amount of the aqueous dispersion of silver shell gold nanorods obtained above was cast on a glass substrate and dried. Since CTAB was not removed, CTAB was deposited on the surface of the glass substrate. After drying, 5 ⁇ L of 35 ⁇ M rhodamine 6G was cast and dried.
  • the Raman scattering spectrum was measured with excitation light of 633 nm with an exposure time of 10 seconds and an integration count of 10. In the obtained spectrum, a peak could be confirmed quite clearly.
  • DDAB dilauryldimethylammonium bromide
  • Example 2 Preparation of CTAC-dispersed gold nanorods
  • a 80 mM CTAB aqueous solution (3 mL) was mixed with a 24 mM chloroauric acid aqueous solution (0.25 mL), acetone (65 ⁇ L), and a 10 mM silver nitrate aqueous solution (20 ⁇ L) to prepare a reaction solution.
  • AS ascorbic acid
  • the AS-reduced solution was put in a quartz cell having an optical path length of 1 cm and irradiated with all light from an ultrahigh pressure mercury lamp (USH-500D: 500 W, manufactured by USHIO INC.). At the time of light irradiation, an ultraviolet transmission filter (Sigma TV Co., UTVAF-33U) was used to cut most of the visible light. Light irradiation was performed for 4 hours. TEM observation of the produced gold nanorods was performed. The obtained gold nanorod aqueous dispersion was centrifuged, and the precipitated gold nanorod was redispersed in an 80 mM CTAC aqueous solution.
  • UTVAF-33U ultraviolet transmission filter
  • the length in the major axis direction was 32.2 ⁇ 9 nm
  • the length in the minor axis direction was 17.2 ⁇ 4 nm
  • the aspect ratio was 1.9 (204 gold Average value of nanorods).
  • Silver shell gold nanorods were produced in the same manner as in Example 1 using the CTAC-dispersed gold nanorods prepared above. Absorption spectrum measurement and TEM observation of the generated silver shell gold nanorods were performed.
  • silver forms a shell with a characteristic shape on the surface of the gold nanorod, although the corners are slightly rounded.
  • the length of the major axis direction of the silver shell gold nanorods obtained from the TEM image was 49.6 ⁇ 7 nm
  • the length of the minor axis direction was 44.2 ⁇ 5 nm
  • the aspect ratio was 1.1 (117 pieces Average value of silver shell gold nanorods).
  • the silver shell grew 17.4 nm in the major axis direction and 27 nm in the minor axis direction.
  • Example 3 Preparation of CTAC-dispersed gold nanorods
  • a gold nanorod dispersion liquid manufactured by Mitsubishi Materials
  • CAB hexadecyltrimethylammonium bromide
  • the length in the major axis direction was 64.8 ⁇ 11 nm
  • the length in the minor axis direction was 8.51 ⁇ 1 nm
  • the aspect ratio was 7.6 (108 gold Average value of nanorods).
  • Silver shell gold nanorods were produced in the same manner as in Example 1 using the CTAC-dispersed gold nanorods prepared above. Absorption spectrum measurement and TEM observation of the generated silver shell gold nanorods were performed.
  • Example 4 A silver shell gold nanorod was prepared in the same manner as in Example 1 except that the amount of the 10 mM AgNO 3 aqueous solution used was 0.25 mL. Absorption spectrum measurement and TEM observation of the generated silver shell gold nanorods were performed.
  • the silver shell gold nanorods obtained from the TEM images have a major axis length of 60.2 ⁇ 8 nm, a minor axis length of 25.6 ⁇ 2 nm, and an aspect ratio.
  • the silver shell grew 9.4 nm in the major axis direction and 15.9 nm in the minor axis direction on average.
  • Example 5 Silver shell gold nanorods were produced in the same manner as in Example 1 except that the amount of the 10 mM AgNO 3 aqueous solution used was 1.0 mL. Absorption spectrum measurement and TEM observation of the generated silver shell gold nanorods were performed.
  • Silver shell gold nanorods obtained from TEM images have a major axis length of 65.0 ⁇ 9 nm, a minor axis length of 41.9 ⁇ 7 nm, and an aspect ratio.
  • the silver shell grew 14.2 nm in the major axis direction and 32.2 nm in the minor axis direction.
  • Example 6 Silver shell gold nanorods were produced in the same manner as in Example 1 except that the amount of the 10 mM AgNO 3 aqueous solution used was 2.0 mL. Absorption spectrum measurement and TEM observation of the generated silver shell gold nanorods were performed.
  • Silver shell gold nanorods determined from TEM images have a major axis length of 70.2 ⁇ 10 nm, a minor axis length of 50.6 ⁇ 6 nm, and an aspect ratio.
  • the silver shell grew 19.8 nm in the major axis direction and 40.9 nm in the minor axis direction.
  • Example 7 Silver shell gold nanorods were prepared in the same manner as in Example 2 except that the amount of 10 mM AgNO 3 aqueous solution used was 0.25 mL. Absorption spectrum measurement and TEM observation of the generated silver shell gold nanorods were performed.
  • Example 8 Silver shell gold nanorods were prepared in the same manner as in Example 3 except that the amount of the 10 mM AgNO 3 aqueous solution used was 0.1 mL. Absorption spectrum measurement and TEM observation of the generated silver shell gold nanorods were performed.
  • Example 9 Silver shell gold nanorods were produced in the same manner as in Example 3 except that the amount of the 10 mM AgNO 3 aqueous solution used was 0.25 mL. Absorption spectrum measurement and TEM observation of the generated silver shell gold nanorods were performed.
  • Example 10 A sample tube containing an 80 mM CTAC aqueous solution (20 mL) was placed in a constant temperature bath with a stirrer set to 15 ° C. and left for 10 minutes. Next, while stirring with a stirrer, the CTAC-dispersed gold nanorods prepared in Example 1 (aspect ratio 5.2; 0.8 mL), 10 mM AgNO 3 aqueous solution (0.5 mL), and 0.1 mM ascorbic acid aqueous solution (1 mL) were added. Added.
  • the color of the reaction solution changed from light red to green to red.
  • the change in color is considerably more gradual compared to the temperature conditions of 30 ° C. (Example 11), 50 ° C. (Example 12) and 70 ° C. (Example 13) described later.
  • the change was slow.
  • the absorption spectrum of the reaction solution was measured 1 hour after the addition of NaOH.
  • money nanorod was performed.
  • Example 11 Silver shell gold nanorods were produced in the same manner as in Example 10 except that the thermostat with a stirrer was set to 30 ° C. Absorption spectrum measurement and TEM observation of the generated silver shell gold nanorods were performed.
  • Silver shell gold nanoparticles having similar shapes tend to be gathered close to each other.
  • the silver shell gold nanorods obtained from the TEM image had a major axis length of 58.2 ⁇ 8 nm, a minor axis length of 33.5 ⁇ 5 nm, and an aspect ratio of 1.7 (132 pieces). Average value of silver shell gold nanorods).
  • the silver shell grew on the average in the major axis direction at 7.4 nm and in the minor axis direction at 23.8 nm.
  • Example 12 Silver shell gold nanorods were produced in the same manner as in Example 10 except that the thermostat with a stirrer was set to 50 ° C. Absorption spectrum measurement and TEM observation of the generated silver shell gold nanorods were performed.
  • the silver shell gold nanorods obtained from the TEM image had a major axis length of 62.2 ⁇ 13 nm, a minor axis length of 35.1 ⁇ 7 nm, and an aspect ratio of 1.8 (96 pieces Average value of silver shell gold nanorods). On average, the silver shell grew 11.4 nm in the major axis direction and 25.4 nm in the minor axis direction.
  • Example 13 Silver shell gold nanorods were produced in the same manner as in Example 10 except that the thermostat with a stirrer was set to 70 ° C. Absorption spectrum measurement and TEM observation of the generated silver shell gold nanorods were performed.
  • the size of the silver shell gold nanoparticles close to a sphere is larger than that in Example 11 (reduction reaction temperature 15 ° C.).
  • the silver shell gold nanorods obtained from the TEM image had a length in the long axis direction of 73.6 ⁇ 12 nm, a length in the short axis direction of 41.7 ⁇ 5 nm, and an aspect ratio of 1.8 (27 pieces Average value of silver shell gold nanorods). On average, the silver shell grew 22.8 nm in the major axis direction and 32 nm in the minor axis direction.
  • the reduction reaction temperature is too low, the silver reduction rate is remarkably reduced, and silver nucleation on the gold nanorod surface is less likely to occur. Therefore, it is expected that large silver shell gold nanorods are likely to be generated.
  • the higher the reduction reaction temperature the thicker the silver shell formed, and the higher the aspect ratio of the resulting silver shell gold nanorods.
  • Example 14 Silver shell gold nanorods were produced in the same manner as in Example 10 except that the CTAC-dispersed gold nanorods prepared in Example 3 (aspect ratio 7.6; 0.8 mL) were used. The color of the reaction solution changed from light red to green. Absorption spectrum measurement and TEM observation of the generated silver shell gold nanorods were performed.
  • Example 15 Silver shell gold nanorods were produced in the same manner as in Example 14 except that the thermostat with a stirrer was set to 30 ° C. Absorption spectrum measurement and TEM observation of the generated silver shell gold nanorods were performed.
  • Example 16 Silver shell gold nanorods were produced in the same manner as in Example 14 except that the thermostat with a stirrer was set to 50 ° C. Absorption spectrum measurement and TEM observation of the generated silver shell gold nanorods were performed.
  • the silver shell gold nanorods obtained from the TEM image had a length in the long axis direction of 77.6 ⁇ 16 nm, a length in the short axis direction of 32.0 ⁇ 6 nm, and an aspect ratio of 2.4 (83 pieces Average value of silver shell gold nanorods). On average, the silver shell grew 12.8 nm in the major axis direction and 23.5 nm in the minor axis direction.
  • Example 17 Silver shell gold nanorods were produced in the same manner as in Example 14 except that the thermostat with a stirrer was set to 70 ° C. Absorption spectrum measurement and TEM observation of the generated silver shell gold nanorods were performed.
  • the silver shell gold nanorods obtained from the TEM image had a major axis length of 85.7 ⁇ 19 nm, a minor axis length of 33.6 ⁇ 6 nm, and an aspect ratio of 2.6 (110 pieces Average value of silver shell gold nanorods). On average, the silver shell grew 20.9 nm in the major axis direction and 25.1 nm in the minor axis direction.
  • the reduction reaction temperature is too low, the silver reduction rate is remarkably reduced, and silver nucleation on the gold nanorod surface is less likely to occur. Therefore, it is expected that large silver shell gold nanorods are likely to be generated.
  • the higher the reduction reaction temperature the thicker the silver shell formed, and the higher the aspect ratio of the resulting silver shell gold nanorods.
  • Example 18 Silver shell gold nanorods were produced in the same manner as in Example 11, the absorption spectrum and light scattering intensity were measured, and the light scattering property was evaluated.
  • the absorption spectrum of the obtained silver shell gold nanorod two absorption peaks were observed around 424 nm and 550 nm.
  • the scattering spectrum (FIG. 19), scattering peaks were observed at 505 nm and 573 nm.
  • two absorption peaks were observed around 500 nm and 870 nm in the absorption spectrum of the gold nanorod forming the core.
  • the absorption spectrum was shifted by a shorter wavelength in the CTAC aqueous solution than in the CTAB aqueous solution (absorption peaks observed at 900 nm and 520 nm). This is considered to be derived from the difference in refractive index between the CTAC protective layer and the CTAB protective layer formed on the gold nanorod surface.
  • the scattering spectrum (FIG. 19) was broad.
  • the concentration of silver shell gold nanorods is diluted 100 times compared to the concentration of gold nanorods. While scattered light from the gold nanorods was hardly observed, high-intensity light scattering was observed from the silver shell gold nanorods despite the 100-fold diluted solution.
  • the light scattering intensity increased by 100 times or more by providing a silver shell to the gold nanorod. This is because gold nanorods were increased in size by being coated with silver, and silver nanoparticles and silver-shell gold nanorods were significantly more light-dissipating and light-scattering than gold nanoparticles of the same shape. It is thought that.
  • Example 19 A core having a gold nanorod core, a silver shell on the core surface, and a gold shell on the shell surface by further forming a gold shell on the surface of the silver shell gold nanorod.
  • -A metal nanomaterial having a double shell structure hereinafter abbreviated as "gold-silver shell gold nanorod" was produced.
  • a 10 mM chloroauric acid aqueous solution (0.13 mL) was quickly added to a silver shell gold nanorod solution (5 mL) prepared in the same manner as in Example 11. The color of the reaction solution changed to magenta in an instant. Absorption spectrum measurement and TEM observation of the produced gold-silver shell gold nanorods were performed.
  • FIGS. 20A and 20B In TEM observation (FIGS. 20A and 20B), a shell made of silver in the first layer and a shell made of gold in the second layer around the gold nanorods due to the difference in electron beam transmittance between gold and silver. It was confirmed that a rectangular parallelepiped gold-silver shell gold nanorod was formed. In addition, hexagonal gold-silver shell gold nanorods and triangular silver shell gold nanorods were also confirmed. Since the oxidation-reduction potential of silver is on the positive side of gold, when gold ions come into contact with the silver shell, a reaction occurs in which silver is dissolved and gold is precipitated. For this reason, it is considered that gold on the surface of the silver shell of the silver shell gold nanorods was dissolved and gold was deposited, thereby producing gold-silver shell gold nanorods.
  • Example 20 (Preparation of spherical gold nanoparticle dispersion in CTAC aqueous solution (hereinafter abbreviated as CTAC-dispersed gold nanoparticle)) 0.2 M K 2 CO 3 aqueous solution (0.75 mL) and 1 M NaSCN aqueous solution (0.3 mL) were added to 50 mL of CTAB aqueous solution (CTAB: 100 mM) containing 0.30 mM chloroauric acid while stirring with a stirrer. The reaction was carried out in a thermostatic bath set at 50 ° C.
  • the obtained gold nanoparticle aqueous dispersion (10 mL) was placed in a centrifuge tube and centrifuged (1000 ⁇ g, 30 minutes).
  • the precipitated gold nanoparticles were redispersed in an 80 mM CTAC aqueous solution. This operation was repeated twice to obtain CTAC-dispersed gold nanoparticles.
  • Example 21 By forming a shell made of gold on the surface of the silver shell gold nanoparticles, a core made of spherical gold nanoparticles, a shell made of silver on the core surface, and a shell made of gold on the shell surface A metal nanomaterial having a core-double shell structure (hereinafter abbreviated as “gold-silver shell gold nanoparticle”) was prepared. A 10 mM chloroauric acid aqueous solution (0.13 mL) was quickly added to a reduction reaction solution (5 mL) containing silver shell gold nanoparticles prepared in the same manner as in Example 20. The color of the reaction solution changed to magenta in an instant. The produced gold-silver shell gold nanoparticles were subjected to absorption spectrum measurement and TEM observation.
  • Example 22 (Preparation of CTAC-dispersed gold nanorods) In the same manner as in Example 1, CTAC-dispersed gold nanorods were obtained.
  • an absorption peak (surface plasmon band) derived from the major axis was observed near 450 nm, and an absorption band (shoulder) was observed near 550 nm.
  • the silver shell gold nanorods had a length in the major axis direction of 61 ⁇ 6 nm, a length in the minor axis direction of 38 ⁇ 3 nm, and an aspect ratio of 1.6 (an average value of 50 silver shell gold nanorods).
  • the silver shell grew on average 12 nm in the major axis direction and on average 28 nm in the minor axis direction.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 30%.
  • Example 23 (Preparation of CTAC-dispersed gold nanorods) In the same manner as in Example 1, CTAC-dispersed gold nanorods were obtained.
  • an absorption peak (surface plasmon band) derived from the major axis was observed near 450 nm, and an absorption band (shoulder) was observed near 550 nm.
  • the silver shell gold nanorods had a length in the major axis direction of 56 ⁇ 6 nm, a length in the minor axis direction of 28 ⁇ 2 nm, and an aspect ratio of 2.0 (an average value of 50 silver shell gold nanorods).
  • the silver shell grew on the average in the major axis direction at 7 nm and on the minor axis direction in an average of 18 nm.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 40%. It can be seen that the shape uniformity (yield of the rectangular parallelepiped silver shell gold nanorods) was improved as compared with Example 22.
  • Example 24 (Preparation of CTAC-dispersed gold nanorods) In the same manner as in Example 1, CTAC-dispersed gold nanorods were obtained.
  • the silver shell gold nanorods had a length in the major axis direction of 56 ⁇ 7 nm, a length in the minor axis direction of 30 ⁇ 1 nm, and an aspect ratio of 1.8 (an average value of 50 silver shell gold nanorods).
  • the silver shell grew on the average in the major axis direction at 7 nm and on the minor axis direction in an average of 20 nm.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 80%.
  • Example 25 The amount of 10 mM AgNO 3 aqueous solution used was changed from 0.25 mL to 0.13 mL, 0.38 mL, and 0.50 mL, and a reduction reaction was performed in the same manner as in Example 24. 150 minutes after the start of the reaction, absorption spectrum measurement and TEM observation of the produced silver shell gold nanorods were performed.
  • the silver shell gold nanorods had a major axis length of 56 ⁇ 9 nm, a minor axis length of 36 ⁇ 3 nm, and an aspect ratio of 1.6 (50 silver shell gold Average value of nanorods).
  • the silver shell grew on the average in the major axis direction by 7 nm and on the minor axis direction by an average of 26 nm.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 90%.
  • the silver shell gold nanorods had a major axis length of 60 ⁇ 6 nm, a minor axis length of 41 ⁇ 3 nm, and an aspect ratio of 1.5 (50 silver shell gold Average value of nanorods).
  • the silver shell grew 11 nm on the average in the major axis direction and 31 nm on the average in the minor axis direction.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 80%. It can be seen from Examples 24 and 25 that the thickness of the formed silver shell increased as the amount of AgNO 3 aqueous solution increased (the silver ion concentration in the reduction reaction system increased). As described above, the formation of the silver shell can be controlled even when the amount of the inorganic silver salt added is changed, and thus a wide range of spectral characteristics can be realized.
  • Example 26 The reduction reaction was carried out in the same manner as in Example 24 by changing the temperature at which the reduction reaction was performed (set temperature of the thermostatic bath) from 30 ° C. to 50 ° C. and 70 ° C. 150 minutes after the start of the reaction, absorption spectrum measurement and TEM observation of the produced silver shell gold nanorods were performed.
  • the silver shell gold nanorods had a length in the major axis direction of 57 ⁇ 4 nm, a length in the minor axis direction of 27 ⁇ 2 nm, and an aspect ratio of 2.1 (50 silver shell gold nanorods Average value).
  • the silver shell grew on the average in the major axis direction at 8 nm and in the minor axis direction at an average of 17 nm.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 80%.
  • the silver shell gold nanorods had a length in the major axis direction of 57 ⁇ 7 nm, a length in the minor axis direction of 31 ⁇ 2 nm, and an aspect ratio of 1.8 (50 silver shell gold nanorods Average value).
  • the silver shell grew on the average in the major axis direction at 8 nm and on the minor axis direction in an average of 21 nm.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 70%.
  • Example 27 (Preparation of CTAC-dispersed gold nanorods) In the same manner as in Example 1, CTAC-dispersed gold nanorods were obtained.
  • FIG. 31 (A): after 5 minutes, (B): after 10 minutes, (C): after 30 minutes, (D) after 90 minutes and (E): after 150 minutes), a rectangular parallelepiped silver shell Formation of gold nanorods was confirmed.
  • the silver shell gold nanorods had a major axis length of 54 ⁇ 7 nm, a minor axis length of 21 ⁇ 2 nm, and an aspect ratio of 2.6 (50 silver shell gold Average value of nanorods).
  • the silver shell grew on the average in the major axis direction at 5 nm and on the minor axis direction in an average of 11 nm.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 20%.
  • the silver shell gold nanorods had a long axis length of 55 ⁇ 8 nm, a short axis length of 21 ⁇ 2 nm, and an aspect ratio of 2.7 (50 silver shell gold Average value of nanorods).
  • the silver shell grew on the average in the major axis direction at 6 nm and on the minor axis direction in an average of 11 nm.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 60%.
  • the silver shell gold nanorods had a major axis length of 55 ⁇ 6 nm, a minor axis length of 22 ⁇ 1 nm, and an aspect ratio of 2.5 (50 silver shell gold Average value of nanorods).
  • the silver shell grew on the average in the major axis direction at 6 nm and on the minor axis direction in an average of 12 nm.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 80%.
  • the silver shell gold nanorods had a long axis length of 57 ⁇ 6 nm, a short axis length of 33 ⁇ 2 nm and an aspect ratio of 1.8 (50 silver shell gold Average value of nanorods).
  • the silver shell grew on the average in the major axis direction at 8 nm and on the minor axis direction in an average of 23 nm.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 80%.
  • the silver shell gold nanorods had a major axis length of 58 ⁇ 6 nm, a minor axis length of 34 ⁇ 2 nm, and an aspect ratio of 1.7 (50 silver shell gold Average value of nanorods).
  • the silver shell grew on the average in the major axis direction at 9 nm and on the minor axis direction in an average of 24 nm.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 80%. According to this example, it was found that the formation of the silver shell can be controlled even when the reduction reaction time is changed, and therefore, it is possible to realize a wide range of spectral characteristics.
  • CTAB hexadecyltrimethylammonium bromide
  • the silver shell gold nanorods had a major axis length of 74 ⁇ 11 nm, a minor axis length of 27 ⁇ 5 nm, and an aspect ratio of 2.8 (an average value of 50 silver shell gold nanorods).
  • the silver shell grew on average in the major axis direction at 8 nm and on average in the minor axis direction by 19 nm.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 70%. According to this embodiment, it is possible to control the formation of the silver shell even if the shape (aspect ratio) of the gold nanorods forming the core is changed, and thus it is possible to realize a wide range of spectral characteristics. I understood.
  • Example 29 (Preparation of CTAC-dispersed gold nanorods) In the same manner as in Example 1, CTAC-dispersed gold nanorods were obtained.
  • the silver shell gold nanorods had a length in the major axis direction of 61 ⁇ 5 nm, a length in the minor axis direction of 35 ⁇ 6 nm, and an aspect ratio of 1.8 (an average value of 50 silver shell gold nanorods).
  • the silver shell grew on average 12 nm in the major axis direction and on average 15 nm in the minor axis direction.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 90%.
  • Example 30 (Preparation of CTAC-dispersed gold nanoparticles) To 10 mL of CTAC (80 mM) aqueous solution containing chloroauric acid (0.25 mM), 0.6 mL of ice-cooled sodium borohydride aqueous solution (10 mM) was added and stirred for 3 hours. A solution obtained by diluting the obtained solution 100 times with pure water was used as a seed solution. Furthermore, 0.12 mL of the seed solution prepared above was added to an aqueous solution (9.88 mL) containing chloroauric acid (0.04 mM), CTAC (10 mM) and ascorbic acid (6 mM) to grow gold nanoparticles. It was. After stirring for 5 hours, the obtained dispersion was used as CTAC-dispersed gold nanoparticles (gold atom concentration: 0.0006 wt%). Absorption spectrum measurement and TEM observation of the obtained gold nanoparticles were performed.
  • Example 31 The addition amount of CTAC-dispersed gold nanorods was changed from 0.4 mL to 0.2 mL, 0.8 mL, 1.2 mL, and 1.6 mL, and a reduction reaction was performed in the same manner as in Example 24. 150 minutes after the start of the reaction, absorption spectrum measurement and TEM observation of the produced silver shell gold nanorods were performed.
  • FIG. 38 In TEM observation (FIG. 38 (A): 0.2 mL, (B): 0.4 mL, (C): 0.8 mL, (D): 1.2 mL, (E): 1.6 mL), the rectangular parallelepiped silver Formation of shell gold nanorods was confirmed.
  • the silver shell gold nanorods had a major axis length of 60 ⁇ 6 nm, a minor axis length of 39 ⁇ 6 nm, and an aspect ratio of 1.5 (50 silver shell gold Average value of nanorods).
  • the silver shell grew on the average in the major axis direction at 21 nm and on the minor axis direction in an average of 29 nm.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 90%.
  • the silver shell gold nanorods had a length of 59 ⁇ 6 nm in the major axis direction, a length of 30 ⁇ 2 nm in the minor axis direction, and an aspect ratio of 2.0 (50 silver shell gold Average value of nanorods).
  • the silver shell grew on the average in the major axis direction at 9 nm and on the minor axis direction in an average of 21 nm.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 90%.
  • the silver shell gold nanorods had a major axis length of 55 ⁇ 6 nm, a minor axis length of 24 ⁇ 2 nm, and an aspect ratio of 2.3 (50 silver shell gold Average value of nanorods).
  • the silver shell grew on the average in the major axis direction at 6 nm and on the minor axis direction in an average of 14 nm.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 90%.
  • the silver shell gold nanorods had a length of 54 ⁇ 6 nm in the major axis direction, a length of 20 ⁇ 2 nm in the minor axis direction, and an aspect ratio of 2.7 (50 silver shell gold Average value of nanorods).
  • the silver shell grew on the average in the major axis direction at 5 nm and on the minor axis direction in an average of 10 nm.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 90%.
  • the silver shell gold nanorods had a length of 55 ⁇ 7 nm in the major axis direction, a length of 17 ⁇ 2 nm in the minor axis direction, and an aspect ratio of 3.2 (50 silver shell gold Average value of nanorods).
  • the silver shell grew on the average in the major axis direction at 6 nm and on the minor axis direction in an average of 7 nm.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 80%. According to this example, it can be seen that the thickness of the formed silver shell decreased as the amount of the CTAC-dispersed gold nanorods increased (that is, the silver ion concentration per gold nanorod decreased). As described above, the formation of the silver shell can be controlled even when the amount of the gold nanoparticles added is changed, and thus a wide range of spectral characteristics can be realized.
  • Example 32 (Preparation of CTAC-dispersed gold nanorods) In the same manner as in Example 1, CTAC-dispersed gold nanorods were obtained.
  • the silver shell gold nanorods had a length in the long axis direction of 53 ⁇ 4 nm, a length in the short axis direction of 31 ⁇ 4 nm, and an aspect ratio of 1.7 (an average value of 50 silver shell gold nanorods).
  • the silver shell grew on average 4 nm in the major axis direction and 21 nm on average in the minor axis direction.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 90%.
  • Example 33 (Preparation of CTAC-dispersed gold nanorods) In the same manner as in Example 1, CTAC-dispersed gold nanorods were obtained.
  • the silver shell gold nanorods had a length in the major axis direction of 59 ⁇ 5 nm, a length in the minor axis direction of 32 ⁇ 2 nm, and an aspect ratio of 1.8 (an average value of 50 silver shell gold nanorods).
  • the silver shell grew on the average in the major axis direction by 10 nm and on the minor axis direction by an average of 22 nm.
  • the yield of the rectangular parallelepiped silver shell gold nanorods was about 90%.
  • the shell made of silver can be formed with good controllability covering the entire surface of the gold nanoparticle serving as the core, and thus the core-shell structured metal nanomaterial having a uniform shape. Can be manufactured with good reproducibility.
  • the metal nanomaterial obtained by the production method of the present invention has excellent optical properties (for example, high light absorption, high light scattering, etc.). In particular, by having a high light scattering property, it can be used for observation of cell dynamics and applied as a sensor particle for an immunoaffinity graph. Moreover, application as a sensor material for surface-enhanced Raman scattering (SERS) spectroscopy can be expected.
  • SERS surface-enhanced Raman scattering

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Abstract

L'invention porte sur un procédé pour produire des nanomatériaux métalliques de forme uniforme, d'une structure coer-écorce, ayant chacun un coer composé d'une nanoparticule d'or et une écorce composée d'argent, avec une bonne reproductibilité. Le procédé pour produire des nanomatériaux métalliques d'une structure coer-écorce, ayant chacun un coer composé d'une nanoparticule d'or et une écorce composée d'argent, comprend une étape de réduction d'ions argent dans une dispersion aqueuse de nanoparticules d'or contenant un sel d'argent minéral et des ions chlorure à l'aide d'un agent de réduction.
PCT/JP2009/051665 2008-02-01 2009-01-30 Procédé pour produire un nanomatériau métallique et nanomatériau métallique obtenu par celui-ci Ceased WO2009096569A1 (fr)

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WO2011071167A1 (fr) * 2009-12-11 2011-06-16 学校法人東京理科大学 Particules à nanotiges cœur-écorce au-ag et leur procédé de production
JP2011179074A (ja) * 2010-03-01 2011-09-15 Utsunomiya Univ 金ナノ粒子及びその製造方法
WO2012046204A1 (fr) * 2010-10-07 2012-04-12 L'oreal Particule comportant deux métaux plasmoniques
WO2012063747A1 (fr) * 2010-11-08 2012-05-18 ナミックス株式会社 Particules métalliques et procédé de fabrication de celles-ci
CN102947026A (zh) * 2010-03-18 2013-02-27 圣地亚哥-德孔波斯特拉大学 制备各向异性的金属纳米颗粒的方法
JP2013057605A (ja) * 2011-09-08 2013-03-28 Kyushu Univ 銀シェル金ナノロッドを用いる分析方法
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Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101468441B1 (ko) 2013-03-14 2014-12-03 한림대학교 산학협력단 크기 제어 가능한 양추형 금 나노결정 합성방법
CN115445615B (zh) * 2022-09-13 2023-06-13 中南大学 一种纳米金属核-壳结构的制备方法

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4705347B2 (ja) * 2004-08-09 2011-06-22 三ツ星ベルト株式会社 非水溶性高分子顔料分散剤で保護された銀コア−金シェル微粒子の製造方法
WO2007103536A2 (fr) * 2006-03-08 2007-09-13 Northwestern University Separation de phases de l'or photo-induite dans des nanoparticules a deux composants pour la formation de nanoprismes
JP2008058209A (ja) * 2006-09-01 2008-03-13 Ricoh Co Ltd 複合金属ナノ粒子、複合金属ナノ粒子を含む多光子吸収反応材料と反応生成物、複合金属ナノ粒子を含む多光子吸収反応助剤

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
JIAN, Z. ET AL.: "Fluorescence spectra characters of silver-coated gold colloidal nanoshells.", COLLOIDS AND SURFACES A : PHYSICOCHEMICAL AND ENGINEERING ASPECTS., vol. 232, January 2004 (2004-01-01), pages 155 - 161 *
LIU, M. ET AL.: "Synthesis and Characterization of Au/Ag Core/Shell Nanorods.", J. PHYS. CHEM. B., vol. 108, no. 19, May 2004 (2004-05-01), pages 5882 - 5888 *

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