Nanocomposite material

FIELD: nanotechnologies.

SUBSTANCE: invention concerns nanotechnologies and is designed for production of nanocomposite materials with efficiently adjustable optic properties, which can be applied in non-linear optics, IT, optic memory device development etc. Nanocomposite material contains nanoparticles, intermediary link molecules (particles changing their spatial configuration under the influence of external light source), and linked molecules (particles exhibiting some optic properties in vicinity of nanoparticles), all three components linked in sequence in a spatial cluster structure. Intermediary link molecules, changing their spatial configuration under the influence of external light source, can include additives - functional substitutes increasing their linking properties.

EFFECT: production of nanocomposite materials capable of efficient changing optic properties under the influence of external light source.

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The invention relates to nanotechnology and aims to create nanocomposite materials with effectively managed optical properties, which can be used in nonlinear optics, information technology, the development of optical memory, etc.

The prior art nanocomposite materials based on nanoparticles in combination with a binder components (EN 2224710 C2, WV 3/00, 2004; EN 2233791 C2, WV 3/00, 2004; EN 2288167 C2, B82B 1/00, 2004). However, the qualitative composition of ingredients known nanocomposite materials does not contain particles with variable optical properties, which does not allow to control their optical properties such as luminescence, and limits the functional and technological capabilities of nanocomposite materials.

The invention is aimed at creating a nanocomposite material with enhanced functionality with the ability to effectively change their optical properties under external influences, mainly in the form of light radiation.

The solution of the problem provided by the fact that the nanocomposite material on the basis of the nanoparticles according to the invention, the structure of the nanocomposite material further comprises an intermediate binding molecule, a particle, changing the spatial QRs is the figuration under external light effects, and svyazyamie molecule-particle optical properties, manifested near the nanoparticles, and the nanoparticles, the intermediate binder molecules and svyazyamie molecules connected in series with the formation of spatial cluster patterns.

In addition, the intermediate binding molecule-particle nanocomposite material that alters the spatial configuration under external light exposures may include the addition of functional substituents that increase their binding properties.

The technical result, which is to create nanocomposite materials with enhanced functionality - the ability to change optical properties under the influence of external light (and, consequently, expanding Arsenal of technical means for a specific purpose - nanocomposite materials), does not follow from the prior art and due to the presence in the nanocomposite material of the intermediate binding molecules of the particles, the impact of which light at certain wavelengths is changing their spatial configuration, mainly in length, and, consequently, the distance between the nanoparticles, near which are localized in a strong electromagnetic field, and svyazyamie molecules-particles with Opticheskie properties, which effectively appear - change near the nanoparticles. It alters the distribution of the distortion of the electromagnetic field svyashenik molecules-particles with optical properties that causes a change in the life time of the excited atoms and molecules of the latter affects the speed of electronic transitions contributing to the processes of absorption and spontaneous emission of light and, accordingly, leads to a reversible change in the spectral characteristics and optical properties of these nanocomposite materials in General.

As nanacast nanocomposite material when implementing the inventive method can be used metal (e.g. gold), semiconductor or dielectric nanoparticles of spherical, ellipsoidal, acicular, sterjnevye, pyramidal or other shape, which guarantees the highest efficiency change properties svyashenik molecules.

As svyashenik molecules can be used particles with fluorescent, photochromic polarizing or other optical properties, effectively manifesting - changing near the nanoparticles (for example, cadmium selenide).

As a binder molecules, which due to the formation of chemical bonds provide stability of the nanostructures can be used cha is based, changing spatial configuration (for example, isomerized) when the external light with a certain wavelength (photoinduced transition), mainly organic molecules with a double bond type carbon-carbon, carbon-nitrogen, nitrogen-nitrogen, and others, capable of CIS-transitorily (for example, molecules of the azo dye), or under the influence of an electric field (EC transition).

As an additional inclusions - functional substituents that improve the binding properties of the intermediate binding molecules can be used, for example, the amino group (-NH₂), aldehyde (-Cho), tighrope (-SH), carboxyl (-COOH) or hydroxyl (-OH)or groups containing these groups.

Get nanocomposite material as follows.

In aqueous suspension, for example, colloidal gold nanoparticles with a diameter of 12÷15 nm is injected at a ratio of 1:12 binder molecules containing two tighrope particles of azo dye 4,4′-dityetrazolo that change their spatial configuration due to a shift from transoceanica in sisseton under the action of radiation at a wavelength of 365 nm and a reverse transition under the action of visible light at a wavelength of 435 nm, the length of the molecules and particles of azo dye varies from 9.5 nm to 5.5 nm and back. When is mesheanii on the surface of the gold nanoparticles formed ligand shell of the binding molecules, particles of azo dye. In the resulting system in the same ratio to the gold nanoparticles 1:12 add aqueous suspension svyashenik molecules, colloidal particles of cadmium selenide (CdSe), optical properties which effect of gold nanoparticles (when the distance between the CdSe particles and gold nanoparticles of 10 nm provides maximum enhancement of the photoluminescence particle CdSe up to 5 times, and at small distances of the order of 5÷2 nm photoluminescence suppressed due to resonance energy transfer from photoexcited CdSe quantum particles to the metal gold nanoparticles). When this occurs the precipitation of the free tigraph ligand shell gold nanoparticles svyashenik molecules-particles of cadmium selenide (CdSe) with the formation of macromolecules, forming a spatial cluster structure of the nanocomposite material. The prepared suspension of nanocomposite material is placed on the mirror glass substrate and dried before the formation of the nanocomposite film.

In the process control optical properties of the resulting nanocomposite material irradiated in a few seconds radiation at a wavelength of 365 nm, translating all of the binder molecules-particles of azo dye in sisseton, in which the distance between the gold nanoparticles and svyazyamie molecules-particles Selena is and cadmium (CdSe) is 9.5 nm, when excitation (irradiation) nanocomposite material with light at a wavelength of 530 nm causes intense red luminescence at a wavelength of about 670 nm, corresponding to the direct interband transition svyashenik molecules-particles of cadmium selenide. For changes in the optical properties capable of intense luminescence nanocomposite material is irradiated within a few seconds of light with a maximum emission near 435 nm, which leads to isomerization of the binder molecules, particles of azo dye (translation of molecules, particles of azo dye in transoceanica) and the decrease of the distance between the gold nanoparticles and svyazyamie molecules-particles of cadmium selenide to 5.5 nm. A subsequent excitation of the nanocomposite material with light at a wavelength of 530 nm causes luminescence, but its intensity is reduced by several tens of times. When re-exposed to light at a wavelength of 365 nm is completely restored the ability of the nanocomposite material to intense red luminescence under the action of the excitation radiation at a wavelength of 530 nm.

The claimed structure of the nanocomposite material can be used as a means for optical recording and reading information due to immediate and pointwise control of optical properties following the m way.

Nanocomposite material pre-uniformly irradiated with light at a wavelength of 435 nm, translating binding molecules-particles of azo dye in transoceanica. Then this nanocomposite material, characterized by low intensity luminescence, irradiated pointwise illumination through a mask, for example, holes with a diameter of 0.3 mm, within a tenth of a second focused radiation at a wavelength of 365 nm, translating binding molecules-particles of azo dye in sisseton only in areas corresponding to the distribution of holes in the mask and exposed. Under uniform excitation of the nanocomposite material with light at a wavelength of 530 nm occurs dot pattern luminescence exactly the mask. Such repeating the mask bitmap picture luminescence remains in the dark indefinitely and may be reproduced excitation at a wavelength of 530 nm or erased subsequent uniform illumination radiation at a wavelength of 365 nm or 435 nm.

Example 2.

Semiconductor luminescent CdSe/ZnS nanoparticles with the structure of the core/shell diameter of 3.2 nm, obtained by a known method in hexane, besieged and resuspendable in an aqueous solution of 4,4′-diaminomethylene. Uzasadnienie 4,4′-diaminomethylene capable of enat their spatial configuration due to a shift from transoceanica in sisseton under the action of radiation at a wavelength of 365 nm and a reverse transition under the action of visible light at a wavelength of 435 nm, the length of the molecule compounds varies from 9.5 nm to 5.5 nm and back. The concentration of 4,4′-diaminomethylene was chosen so that 1 mg of the nanoparticles had 5 mg of 4,4′-diaminomethylene. Uzasadnienie forms on the surface of the nanoparticle ligand shell due to the interaction of one amino group and the zinc atom and the other amino group is free, what causes aggregate stability of CdSe/ZnS nanoparticles. Free amino groups on the surface of the nanoparticles are functional for prishivki to them a variety of protein molecules, in particular, photochromic protein bacteriorhodopsin. Proshivka bacteriorhodopsin to the surface of CdSe/ZnS nanoparticles stabilized by molecules of 4,4′-diaminomethylene, at the expense of self-organization processes initiated by the interaction of the positively charged amino groups 4,4′-diaminomethylene and negatively charged carboxyl groups of residues of aspartic and glutamic acids included in the amino acid sequence of the polypeptide patterns of bacteriorhodopsin. The formation of the nanocomposite material is carried out by mixing the suspension of bacteriorhodopsin and CdSe/ZnS nanoparticles stabilized by molecules of 4,4′-diaminomethylene in a molar ratio of 8:1 and expositie the resulting solution for 2 hours.

Formed in the nanocomposite material photocell bacteriorhodopsin has undergone significant changes during the translation of the molecule 4,4′-diaminomethylene of TRANS - sisseton (decrease in the length of the molecule) was observed the increase of the life time of the intermediate M 12.5 times and the quantum yield of the reaction transition BR→M increased from 20-25% to 40-50%.

Example 3.

In aqueous suspension of metallic silver nanoparticles with a diameter of 21 nm is injected at a ratio of 1:25 binding molecule 4,4′-diaminomethylene. Uzasadnienie 4,4′-diaminomethylene able to change its spatial configuration due to a shift from transoceanica in sisseton under the action of radiation at a wavelength of 365 nm and a reverse transition under the action of visible light at a wavelength of 435 nm, the length of the molecule compounds varies from 9.5 nm to 5.5 nm and back. Uzasadnienie forms on the surface of the nanoparticle ligand shell due to the interaction of one amino group and an atom of silver, and the other amino group is free, that causes the aggregate stability of the nanoparticles. Free amino groups on the surface of the nanoparticles are functional for prishivki to them a variety of protein molecules, in particular, photochromic protein bacteriorhodopsin. Proshivka bacteriorhodopsin to the surface and nanoparticles of silver, stable molecules 4,4′-diaminomethylene, at the expense of self-organization processes initiated by the interaction of the positively charged amino groups 4,4′-diaminomethylene and negatively charged carboxyl groups of residues of aspartic and glutamic acids included in the amino acid sequence of the polypeptide patterns of bacteriorhodopsin. The formation of the nanocomposite material is carried out by mixing the suspension of bacteriorhodopsin and silver nanoparticles stabilized by molecules of 4,4′-diaminomethylene in a molar ratio of 8:1 and the exposure resulting solution for 2 hours.

The spectral characteristics of the formed nanocomposite material showed the presence of a new spectral absorption band at a wavelength of 365 nm. In addition, increases the intensity of the absorption band at the wavelength of 400-410 nm.

1. Nanocomposite material containing nanoparticles, characterized in that the structure of the nanocomposite material further includes an intermediate binding molecule, a particle, changing the spatial configuration under external light exposures, and svyazyamie molecule-particle optical properties, manifested near the nanoparticles, and the nanoparticles Prohm the weft binder molecules and svyazyamie molecules connected in series with the formation of spatial cluster nanostructures.

2. Nanocomposite material according to claim 1, characterized in that an intermediate binding molecule, a particle, changing the spatial configuration under external light exposures, provide additional on - functional substituents that increase their binding properties.