Method of producing nanostructured metal oxide coatings

FIELD: chemistry.

SUBSTANCE: method comprises preparing an alcohol solution of β-diketonates of one or more p-, d- or f-metals with concentration 0.001h2 mol/l; heating the solution to 368-523 K and holding at said temperature for 10-360 minutes to form a metal alkoxo-β-diketonate solution; depositing the obtained solution in droplets at the centre of a substrate being rotated at a rate of 100-16000 rpm, or immersing the substrate into said solution at a rate of 0.1-1000 mm/min at an angle of 0-60° to the vertical; holding the substrate with a film of the alkoxo-β-diketonate solution at 77-523 K until mass loss ceases, to form xerogel on the surface of the substrate; crystallising oxide from the xerogel at 573-1773 K.

EFFECT: invention enables to obtain single- or multilayer dense and porous, amorphous and crystalline nanostructured oxide coatings with ordered particle size ranging from 1 nm to 100 nm with given functional properties.

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The invention relates to the field of synthesis of metal oxides of simple and complex composition having dielectric or semiconductor properties, in the form of thin nanostructured coatings on the surface of products of various shapes that perform safety functions during operation at high, 2300 K and higher temperatures in oxygen-containing atmosphere having an important optical, magnetic, catalytic and other functional properties, which makes it promising for their use in the fields of industry and technology as aircraft and rocket engineering, optics and electronics, nanostructured state of the synthesized coatings can be applied in catalysis and chemosensory, as well as ceramic pigments.

In the analysis of scientific publications and international achievements in the field of production of nanostructured oxide coatings confirmed the relevance of this issue, which stems from the great practical significance of the study materials.

The most common ways of obtaining nanocrystalline oxide coatings are chemical precipitation of their gas phase (CVD, including with the use of ORGANOMETALLIC compounds - MOCVD), atomic layer deposition (ALD) and the Sol-gel method. At the same time more simple and universal is the latest.

the most cases, with the development of nanostructured coatings as precursors are volatile compounds alkoxides, oxoalkoxide, chlorides, β-diketonates metals and ORGANOMETALLIC compounds.

In the known methods of obtaining oxide coatings [US 5922405, US 5998644, US 6063951] the authors proposed to use as precursors of volatile ORGANOMETALLIC compounds with the General formula R12AlOR2(when receiving films of aluminum oxide; R1, R2- C1-10is an alkyl group), M[(µ-OR')2M R2]2(upon receipt of oxide films of the composition of the MM'2O4where M Is Be, Mg, Zn or Cd; M' Is Al or Ga; R, R' - C1-10is an alkyl group). The method of chemical vapor deposition (CVD) received the oxide coating by evaporation of these compounds. However, significant shortcomings of the method should include complex multi-stage methodology for the synthesis of precursors and the use of compounds containing alkali metals and Halogens, which significantly increases the requirements for the clearing of them target compounds.

In the invention [US 7501153B2, US 7714155B2] proposed when the coatings of oxides and nitrides of metals by the method of chemical vapor deposition (CVD) to use as a precursor alkoxides and mixtures of alkoxides of metals with a branched carbon skeleton. It should be noted that the use of alkoxides of metals upon receipt of an oxide or nitride coating is rather difficult their high hydrolytic activity, increasing requirements to the hardware design and the conditions of storage and transportation; upon receipt of oxide coatings containing several different metals, using a mixture of their alkoxides with different volatility due to differences in physico-chemical properties, it is difficult to obtain a given ratio of the metals, as evidenced by the examples in these publications.

A method of obtaining coatings of barium titanate BaTiO3[EP 0079392 A1] a method of dip-coating based on the use as precursors of oxoalkoxide metals. In the described example, the coating deposited on the surface of the quartz plate when it is pulling from the alcohol solution used precursor with a speed of 40 cm/min, then was done drying and subsequent annealing at 1373 K for 3 hours, resulting in a coating BaTiO3. The disadvantages of this method must be attributed to the difficulty of obtaining coatings of more complex composition, which is associated with the use of precursors, which is difficult to vary the ratio of barium and titanium, as well as the lack of data on the hydrolytic activity of the used connections and dependencies of the viscosity of their solutions from the time that largely determine the properties of the obtained coatings.

The authors of inventions [EP 0527661 A1] and [EP 0554246 B1] offer for the floor is possible coatings of oxides and fluorides of metals, as well as metal films by the CVD method to use as precursors of β-diketonates of the respective metals. In this case, the main difficulty is to obtain coatings of complex composition with a specified ratio of the metals that is limited to the different volatility of β-diketonates of the respective metals.

The authors of the invention [US 7592251 B2] atomic layer deposition receive a coating of oxides of tantalum, hafnium and titanium, using as precursors of nitrates, chlorides, iodides and alkoxides of metals. A method of obtaining a metal nitride coatings and multilayer combinations [US 8133555 B2] atomic layer deposition comes from the use of β-diketonates of the respective metals ([Co(DPM)3], [Ru(DPM)3], [Cu(hfac)tmvs] and C11H29N4Ta - TAIMATA). In this and the above-described inventions, there is a limit in obtaining coatings of complex composition, which is associated with differences in the properties of the used precursors.

The authors of inventions [US 20070295273 A1, US 7648926 B2] to obtain films in the system of Al2O3-Y2O3atomic layer deposition propose to use as reagents triethylaluminium Al(C2H5)3and 2,2,6,6-tetramethyl-3,5-garagentore [Y(tnd)3]. In this case, as for the above inventions, a significant drawback I have is the use of precursors with different properties (volatility and sorption capacity), this is reflected in zatrudnienie coatings of complex composition with a specified ratio of metals.

The method of obtaining photocatalytic coatings [WO 2004014986 A1] (prototype) is the closest technical solution from a technological point of view. The authors suggest that when receiving a film-forming solution as precursors to use alkoxides of aluminum and titanium, as well as particles of titanium oxide. The methodology consists in the preparation of film-forming solution containing water, methanol, β-diketone (acetylacetone, 2,4-heptanedione, 3,5-heptanedione, 2,4-attention), an acid (acetic or nitric), which is then heated to a temperature of about 340 K, then is added to the alkoxide of aluminum (isopropoxide aluminum Al(OCH(CH3)2)3or n-piperonyl aluminum Al(OCH9)3), the solution is maintained at boiling for about 2 hours, then cooled with stirring. In the resulting solution are added particles of titanium oxide and then it is put by a method of spin-coating onto a glass substrate and dried at a temperature of 293-303 To within 24 hours with the formation of the photocatalytic coating. You can also use isopropoxide titanium Ti(OCH(CH3)2)4by inserting it into the solution together with particles of titanium oxide, for subsequent joint hydrolysis of the aluminum alkoxide. Use the W β-diketonate due to the need to reduce the hydrolytic activity of the aluminum alkoxide and improve the stability of the obtained film-forming solution. To improve the stability of the solutions proposed the use of different surfactants.

The above invention has a number of technological shortcomings. Namely, you want to use a large number of reagents, which complicates and increases the cost method. When one component is toxic alcohol is methanol. As sources of metals are encouraged to use their alkoxides, are often complicated by their instability and increased hydrolytic activity, which leads to difficulties in the synthesis of complex oxides of the composition. Alkoxides of different metals have different properties, so when receiving a mixed-forming solutions with different ratios of metals, it is difficult to predict its characteristics - viscosity, fluidity and long-term stability. The proposed methodology does not allow to vary the viscosity of the obtained solutions and its change in time to control the morphology of the resulting films.

The present invention is directed to the development of a simple and efficient way to obtain nanostructured coatings of metal oxides, including complex composition, using as precursors hydrolytically active solutions alkoxo-β-diketonates, metal-specified and controlled ordinationem environment of the Central atoms.

The technical result is achieved by the method for obtaining nanostructured coatings of metal oxides, namely, that serves alcohol solution of β-diketonates one or more p-, d - or f-metals with a concentration of 0.001÷2 mol/l, the solution is heated to 368÷523 K and maintained at this temperature for 10÷360 minutes prior to the formation of a mixture of alkoxo-β-diketonates metal, the resulting solution was dropwise applied to the Central part of the substrate which rotates with a speed of 100÷6000 rpm, or in a specified the solution immerse the substrate with a speed of 0.1÷1000 mm/min at an angle vertically 0÷60°, after which withstand a substrate coated with a film of a solution of alkoxo-β-diketonates at 77÷523 K To stop the weight loss with the formation of a xerogel on the surface of the substrate, followed by crystallization of the oxide of the xerogel at 573÷1773 K.

It is important that as alcohols sources of alkoxo group used single - and multi-atom, linear and branched alcohols.

It is possible that alcohol solution additionally contains aliphatic and aromatic hydrocarbons and their halogen derivatives, ethers, aldehydes, ketones, organic acids and other organic solvents in amounts necessary to achieve the solution boiling point in the range of 368÷523 K.

Also possible is that the resulting alcoholic solution of alkoxo-β-diketonates metal pre-hydrolized by adding a water-alcohol solution at a molar ratio of water to metal 0,5÷10.

It is advisable that the application of a film of a solution of alkoxo-β-diketonates metal on a substrate is carried out at a solution temperature of 273 to 523 K and the temperature of the substrate 273÷1273 K.

It is also advisable that the substrate material is chosen from a number of: silicon, silicon carbide, aluminum oxide.

It is preferable that the curing of the substrate coated with a film of a solution of alkoxo-β-diketonates to halting the loss of mass is carried out at pressures of 1·10-5÷1 ATM.

It is also important that the process of crystallization of the oxide of the xerogel is carried out at pressures of 1·10-5÷1 ATM.

It is also possible that after crystallization of the oxide of the xerogel spend additional annealing the substrate with the xerogel in a period of from 1 minute to 24 hours in an oxidizing or inert atmosphere at temperatures of 573÷1773 K.

The essence of the invention lies in the fact that hydrolytically active solutions alkoxo-β-diketonates p-, d - or f-metals with controlled coordination environment of the Central atoms derived from stable under normal conditions of β-diketonates of the respective metals allows to synthesize nanostructured thin oxide coating and multilayer materials with desired protective, optical, magnetic and other functional properties. Controlled synthesis of glycaemia in obtaining smeshanoligandnykh coordination compounds of a given composition and structure, the defining properties of a formed hydrolytically active solutions and oxide coatings.

In the synthesis of alkoxo-β-diketonates metal as alcohols sources of alkoxo group used single - and multi-atom, linear and branched alcohols. Structure used alcohol affects the degree of shielding of the Central atoms in the formed smeshanoligandnykh complexes, so you can control their hydrolytic activity. As solvents can act as themselves alcohols, and aliphatic and aromatic hydrocarbons and their halogen derivatives, ethers, aldehydes, ketones, organic acids and other organic solvents in amounts necessary to achieve the solution boiling point in the range of 368÷523 K. this temperature range is due to the fact that during the heat treatment of a solution of β-diketonates metal at a temperature below 368 destructive To the substitution of the β-diketonate ligands on alkoxo band practically does not occur, and above 523 To the high rate of substitution makes it difficult to control the degree of its passage from education smeshanoligandnykh connections required composition. Used β-diketonates metals have the composition [M(RCO)CHC(O)')x], where M - p-, d - or f-metal, R and R' is a linear or branched alkyl radicals, including ftory the bathrooms. From the structure of the β-diketonate ligands also depends on the degree of shielding of the Central atom and, accordingly, the hydrolytic activity of generated alkoxo-β-diketonates metal. In addition to the composition and structure of the chelate and CNS fragments hydrolytic activity of the synthesized coordination compounds also determines the degree of substitution of the first on the second. This option is controlled by the heat treatment alcohol solution of β-diketonates metal. As a result, by varying the temperature of the solution in the interval 368÷523 K and the heat treatment time is from 10 to 360 minutes, controllable synthesis of alkoxo-β-diketonates metal with the desired ratio of ligands in determining their hydrolytic activity. Thus obtained solutions are used as precursors in the synthesis of simple and complex oxides of the composition in the form of thin nanostructured coatings.

Before applying a film of a solution of alkoxo-β-diketonates metal on a substrate to him can also be added gidrolizuemye component, which leads to hydrolysis smeshanoligandnykh alkoxo-β-diketonates metal, accompanied by an increase in viscosity and gel formation. As gidrolizuemye component is water or alcohol solution added to a solution of alkoxo-β-diketonato the metals in the ratio n(H 2O/n(M)=0,5÷10. When the value of the ratio n(H2O)/n(M)<0.5 amount of water is not enough to complete hydrolysis and increasing the viscosity of the solution, and when the ratio of n(H2O)/n(M)>10 may precipitation and undesirable phase separation when using solutions containing complexes of different metals. Controlled degree of substitution of the β-diketonate ligands and a certain dependence of the solution viscosity with time after adding gidrolizuemye component allow direct way to vary the properties of the obtained coating thickness, morphology, porosity, adhesion and, therefore, their functional characteristics.

On the characteristics of the obtained oxide film is influenced by the temperature of the solution, alkoxo-β-diketonates metal at the time of application to the surface of the substrate. This is explained by the variation of viscosity and fluidity of the liquid by changing the temperature. The temperature of the solution ranges from 273 to 523 K. the Choice of this interval is due to the fact that when the temperature of the solution below 273 To its high viscosity makes it difficult to obtain a thin continuous coating, and the upper value 523 corresponds To its highest possible boiling point. Properties of the obtained oxide coatings also depend on the characteristics of the substrate, namely, the roughness (surface m which can be atomically smooth, and to have a height difference of up to 100 μm), porosity and temperature, the value of which ranges from 273 to 1273 K. depending on the temperature of the substrate changes its wettability when applied film hydrolytically active solution, which affects the properties of the obtained coatings. When the temperature of the substrate <273 To the low value of its wettability it difficult to obtain a uniform coating, and at a temperature of >1273 To possible unwanted chemical interaction resulting coating to the substrate.

As the substrate material, which is causing the oxide film, use sapphire, silicon, silicon carbide and other ceramic or metal material, which surface you want to protect or modify. The choice of material of the substrate, based on the possession of high melting point to reduce the likelihood of chemical interaction with the resulting oxide coating during the coating process.

When applying the film of solution on the surface of the substrate by the rotation method called by the method of spin-coating, the rotation speed of the substrate varies in the range from 100 to 16000 rpm This parameter controls the thickness, uniformity and morphology of the resulting coating. The solution in the required amount dropwise applied to the Central region of the surface of podlog and, followed by its rotation, accompanied by the distribution of fluid across the surface until formation of a uniform coating. You might also consider applying hydrolytically active solution on the surface of the substrate during its rotation. Depending on the solvent, concentration of metals and viscosity of the fluid by the rotation of the sample is from 10 seconds to 60 minutes.

In the case of deposition of a film of the resulting solution of alkoxo-β-diketonates metal by immersion of the substrate, the so-called method of dip-coating, the sink rate is from 0.1 to 1000 mm/min, which determines the thickness, uniformity and morphology of the resulting coating. The substrate during immersion has a tilt angle of the vertical from 0 to 60°. This parameter also affects the film properties, including the gradient of its thickness on the substrate surface.

After application of the film hydrolytically active solution on the substrate it is maintained at a temperature of 77÷523 K and at the pressure of 1·10-5÷1 ATM until the cessation of mass loss, which leads to the formation of a xerogel film. Low pressure leads to the intensification of the process of solvent removal. The reduction of pressure below 1·10-5ATM is impractical and leads to technological complexity of the process, and at a pressure above 1 ATM removing the solvent the C volume film hydrolytically active solution will slow down.

For formation of an oxide coating a substrate with a film xerogel is subjected to heat treatment at 573÷1773 K and at pressures of 1·10-5÷1 ATM in an oxidizing atmosphere, an inert gas (Ar, N2or in the mixture gas. The choice of temperature range due to the fact that below 573 K, the crystallization of the oxide occurs at a low speed, and the temperature increase above 1773 K leads to active aggregation of particles of the oxide coating and their interaction with the substrate material. Low blood pressure during synthesis facilitates the removal of gases released during decomposition of the organic components of the precursor. The reduction of pressure below 1·10-5ATM and rise above 1 ATM leads to technological complexity of the process and impractical. It is also possible to conduct additional heat treatment of the substrate with the film xerogel during the time from 1 minute to 24 hours. Increasing the synthesis time is more than 24 hours leads to further aggregation of the oxide particles and is not economically justified, while less than 1 min may be sufficient for crystallization of the oxide film.

To increase the thickness of the coating or modification of its properties oxides of other compositions can be applied on its surface as described above, additional layers of oxide films. As a result of the treatment is described multilayer nanostructured oxide coating with a protective, optical, magnetic, catalytic, sensor and other functional properties, defined by combinations of oxide layers of different chemical composition.

The invention is illustrated in the following micrographs of the surface of the formed oxide coating:

Figure 1. Micrograph of the surface of the nanostructured thin film composition ZrO2obtained at a temperature of 1473 K on the surface of the polished wafer of monocrystalline silicon (example 1).

Figure 2. Micrograph of the surface of the nanostructured thin film of the composition of 0.08 Y2O3-0,92 ZrO2obtained at a temperature of 1473 K on the surface of the polished wafer of monocrystalline silicon (example 4).

Figure 3. Micrograph of the surface of the nanostructured thin film of the composition of 0.15 Y2O3-0,60 ZrO2-0,25 HfO2obtained at a temperature of 1073 K on the surface of the polished wafer of monocrystalline silicon (example 5).

Figure 4. Micrograph of the surface of the nanostructured thin film of the composition of 0.15 Y2O3-0,60 ZrO2-0,25HfO2obtained at a temperature of 1473 K on the surface of the polished wafer of monocrystalline silicon (example 6).

Figure 5. Micrograph of the surface of the nanostructured thin film of the composition of Y3Al5O12, is received at a temperature of 1473 K on the surface of the polished sapphire wafer (example 9).

Figure 1-4 shows a micrograph obtained by scanning electron microscopy using a three-beam workstation Carl Zeiss NVision40, and figure 5 presents a topographic image of the surface of the oxide coating obtained by the method of atomic force microscopy using a scanning probe microscope Solver PRO-m. the results Obtained indicate the ordered state of oxide films consisting of nanoparticles.

Below is illustrating, but not limiting the proposed method examples of making nanostructured thin films of oxides of both simple and complex composition to various substrates.

Example 1. In 80 ml of isoamyl alcohol was dissolved 5,23 g [Zr(C5H7O2)4], after which the solution was kept in a round bottom flask with reflux condenser at a temperature of 404±5 To 30 minutes. The resulting solution arcoxiazapomnit zirconium hereinafter was applied on the polished surface of a substrate of monocrystalline silicon when it is immersed in the solution at a speed of 500 mm/min. and the Temperature of the solution and the substrate during coating film was 293 K. it was Further held ageing of the substrate with the applied film of the solution at 343 K for 1 h before the termination of the mass loss with the formation of a xerogel on the surface of the substrate and subsequent Krista is the centralization of the oxide film when heated to 1473 K in air. As a result, the surface of the Si substrate was formed nanostructured thin film of zirconium oxide formed from particles with an average size of 42 nm, determined using scanning electron microscopy (Figure 1). X-ray surface analysis confirmed the formation phase of zirconium oxide.

Example 2. In a mixture of 70 ml of isoamyl and 10 ml of amyl alcohol was dissolved 5,23 g [Zu(S5H7C2)4], after which the solution was kept in a round bottom flask with reflux condenser at a temperature of 405±5 for 25 minutes. The resulting solution arcoxiazapomnit zirconium hereinafter was applied on the polished surface of a substrate of monocrystalline silicon when it is immersed in the solution at a speed of 500 mm/min. and the Temperature of the solution and the substrate during coating film was 293 K. Then produced artificial substrate coated with a film of the solution at 343 K for 1 h before the termination of the mass loss with the formation of a xerogel on the surface of the substrate and subsequent crystallization of the oxide film when heated to 1073 K in air. As a result, the surface of the Si substrate was formed nanostructured thin film of zirconium oxide formed from particles with an average size of 15 nm, determined using scanning electron microscopy. X-ray Ana is from the surface confirmed the formation phase of zirconium oxide.

Example 3. In a mixture of 35 ml of isoamyl and 5 ml n-butyl alcohol dissolved 2.25 g [Zr(C5H7O2)4] and 0.88 g [Y(hfa)3], after which the solution was kept in a round bottom flask with reflux condenser at a temperature of 403±5 To 50 minutes. The resulting solution of alkoxo-β-diketonates of zirconium and yttrium hereinafter was applied on the polished surface of a substrate of monocrystalline silicon when it is immersed in the solution at a speed of 300 mm/min. and the Temperature of the solution and the substrate during coating film was 298 K. Further was done keeping the substrate with the applied film of the solution at 323 K for 2 hours before the termination of the mass loss with the formation of a xerogel on the surface of the substrate and subsequent crystallization of the oxide film when heated to 1073 K in air. As a result, the surface of the Si substrate was formed a thin nanostructured oxide film composition 0,08 Y2O3-0,92 ZrO2formed from particles with an average size of 13 nm, determined using scanning electron microscopy. X-ray surface analysis confirmed the formation phase of zirconium oxide stabilized with yttrium.

Example 4. In a mixture of 18 ml of isoamyl alcohol and 22 ml of cumene dissolved and 2.26 g of [Zr(C5H7O2)4] and 0.44 g [Y(C5H7O2)3], p is the following which the solution was kept in a round bottom flask with reflux condenser at a temperature of 404±5 within 45 minutes. The resulting solution alkoxilierungen zirconium and yttrium hereinafter was applied on the polished surface of a substrate of monocrystalline silicon when it is immersed in the solution at a speed of 300 mm/min. and the Temperature of the solution and the substrate during coating film was 298 K. Further was done keeping the substrate with the applied film of the solution at 323 K for 2 hours before the termination of the mass loss with the formation of a xerogel on the surface of the substrate and subsequent crystallization of the oxide film when heated to 1473 K in argon atmosphere and after cooling to remove from the scope of the oxide film of carbon, formed from the organic components of the precursor were heated to 1473 K in air. As a result, the surface of the Si substrate was formed nanostructured thin film composition of 0.08 Y2O3-0,92 ZrO2formed from particles with an average size of 32 nm, determined using scanning electron microscopy (Figure 2). As can be seen, the pre-crystallization film in an inert atmosphere with the subsequent removal of carbon leads to the formation of coatings with greater porosity. X-ray surface analysis confirmed the formation phase of zirconium oxide stabilized with yttrium.

Example 5. In 72 ml of isoamyl alcohol was dissolved 2,41 g [Zr(C5H7 O2)4], 1.56 g [Hf(C5H7O2)4] and 1.36 g [Y(C5H7O2)3], after which the solution was kept in a round bottom flask with reflux condenser at a temperature of 404±5 for 40 minutes. The resulting solution alkoxilierungen zirconium, hafnium and yttrium hereinafter was applied on the polished surface of a substrate of monocrystalline silicon when it is immersed in a solution with a speed of 700 mm/min, the Temperature of the solution and the substrate during coating film was 293 K. Then produced artificial substrate coated with a film of the solution at 353 K for 1 h before the termination of the mass loss with the formation of a xerogel on the surface of the substrate and subsequent crystallization of the oxide film when heated to 1073 K in air. As a result, the surface of the Si substrate was formed a thin nanostructured oxide film composition of 0.15 Y2O3and-0.6 Zr2-0,25 HfO2formed from particles with an average size of 12 nm, determined using scanning electron microscopy (Figure 3). X-ray surface analysis confirmed the formation of phase oxide of zirconium-hafnium, yttrium-stabilized.

Example 6. Obtained according to the method described in Example 5, a solution alkoxilierungen zirconium, hafnium and yttrium was applied on the polished surface mean the key of monocrystalline silicon when it is immersed in a solution with a speed of 700 mm/min The temperature of the solution and the substrate during coating film was 293 K. Then produced artificial substrate coated with a film of the solution at 353 K for 1 h before the termination of the mass loss with the formation of a xerogel on the surface of the substrate and subsequent crystallization of the oxide film when heated to 1473 K in air. As a result, the surface of the Si substrate was formed a thin nanostructured oxide film composition of 0.15 Y2O3-0,60 ZrO2-0,25 HfO2formed from particles with an average size of 34 nm, determined using scanning electron microscopy (Figure 4). As can be seen, with increasing temperature there is an increase in the average size of particles that formed oxide film. X-ray surface analysis confirmed the formation of phase oxide of zirconium-hafnium, yttrium-stabilized.

Example 7. Obtained according to the method described in Example 5, a solution alkoxilierungen zirconium, hafnium and yttrium were applied to the surface of the polished substrate of monocrystalline silicon when it is immersed in a solution with a speed of 700 mm/min, the Temperature of the solution and the substrate during coating film was 293 K. Then produced artificial substrate coated with a film of the solution at 353 K for 1 h before the termination of the mass loss with the formation of the COP is rogala on the surface of the substrate and subsequent crystallization of the oxide film when heated to 1473 K in argon atmosphere and after cooling to remove from the scope of the oxide film of carbon, formed from the organic components of the precursor were heated to 1473 K in air. As a result, the surface of the Si substrate was formed a thin nanostructured oxide film composition of 0.15 Y2O3-0,60 ZrO2-0,25 HfO2formed from particles with an average size of 59 nm, determined using scanning electron microscopy. X-ray surface analysis confirmed the formation of phase oxide of zirconium-hafnium, yttrium-stabilized.

Example 8. In 34 ml of isoamyl alcohol was dissolved 1,30 g [Al(C5H7O2)C] and 1,33 g [Y(tfa)3], after which the solution was kept in a round bottom flask with reflux condenser at a temperature of 404±5 K for 5 hours. The resulting solution of alkoxo-β-diketonates of aluminum and yttrium then applied to the surface of the polished sapphire substrate when it is immersed in the solution at a speed of 250 mm/min, the Temperature of the solution and the substrate during coating film was 293 K. Then produced artificial substrate coated with a film of the solution at 343 K for 1 h before the termination of the mass loss with the formation of a xerogel on the surface of the substrate and subsequent crystallization of the oxide film when heated to 1273 K in air. As a result, the surface of the sapphire substrate was formed a thin nanostar churromania oxide film composition Y 3Al5O12formed from particles with an average size of 50 nm, determined using atomic force microscopy. The maximum elevation on an area of 25 μm2was 20 nm. X-ray surface analysis confirmed the formation of phase yttrium-aluminum garnet.

Example 9. In 34 ml of isoamyl alcohol was dissolved 1,30 g [Al(C5H7O2)3] and 0.94 g [Y(C5H7O2)3], after which the solution was kept in a round bottom flask with reflux condenser at a temperature of 404±5 K for 5 hours. The resulting solution alkoxilierungen aluminum and yttrium then applied to the surface of the polished sapphire substrate when it is immersed in the solution at a speed of 250 mm/min, the Temperature of the solution and the substrate during coating film was 293 K. Then produced artificial substrate coated with a film of the solution at 343 K for 1 h before the termination of the mass loss with the formation of a xerogel on the surface of the substrate and subsequent crystallization of the oxide film when heated to 1473 K in air. As a result, the surface of the sapphire substrate was formed a thin nanostructured oxide film composition Y5Al5O12formed from particles with an average size of 100 nm, determined using atomic force microscopy (Figure 5). The maximum is tional elevation on an area of 25 μm 2was 72 nm. X-ray surface analysis confirmed the formation of phase yttrium-aluminum garnet.

Example 10. In 27 ml of isoamyl alcohol was dissolved 1.08 g [Fe(C5H7O2)3] 0,76 g [Y(C5H7O2)3], after which the solution was kept in a round bottom flask with reflux condenser at a temperature of 404±5 K for 4 hours. The resulting solution alkoxilierungen iron and yttrium then applied to the surface of the polished sapphire substrate when the rotation speed of 3000 Rev/min the Temperature of the solution when applied his film was 313 K, and the temperature of the substrate was set to 303 K. Then produced artificial substrate coated with a film of the solution at 343 K for 1 h before the termination of the mass loss with the formation of a xerogel on the surface of the substrate and subsequent crystallization of the oxide film when heated to 1273 K in air. As a result, the surface of the sapphire substrate was formed a thin nanostructured oxide film composition Y5Fe5O12formed from particles with an average size of 60 nm, determined using scanning electron microscopy. X-ray surface analysis confirmed the formation phase of the yttrium-iron garnet.

Thus, the developed method has the following pre what modestly:

- allows you to obtain nanostructured oxide coating both simple and complex composition at relatively low temperatures;

the ratio of metals in obtaining the oxide film of complex composition is set at the stage of loading β-diketonates in obtaining the solution alkoxo-α-diketonates metals; primordial differences in physico-chemical properties of the data coordination compounds do not lead to the deviation of the composition from a given;

- based on the use of stable under standard conditions reagents β-diketonates metal;

controlled synthesis of precursors - smeshanoligandnykh hydrolytically active coordination compounds (alkoxo-β-diketonates metal) allows for changes in their composition and structure of the Sol-gel method to obtain nanostructured thin oxide coatings according to functional properties (shielding, optical, magnetic, catalytic, and others);

well - known dependence of the viscosity of the hydrolytically active solutions alkoxo-β-diketonates metal from the time when the hydrolysis also gives the possibility of obtaining nanostructured oxide coatings with controlled characteristics.

The invention allows to obtain single-layer and multi-layered, dense and porous, amorphous and crystalline nanostructured oxide is ocrite with the size of the ordered particles from units to hundreds of nanometers using hydrolytically active alcohol solutions of alkoxo-β-diketonates metal with controlled coordination environment, synthesized on the basis of their β-diketonates. The resulting surfaces have a protective, magnetic, optical, sensor, catalytic and other functional properties.

1. The method of obtaining nanostructured coatings of metal oxides, namely, that serves alcohol solution of β-diketonates one or more p-, d - or f-metals with a concentration of 0.001÷2 mol/l, the solution is heated to 368÷523 K and maintained at this temperature for 10÷360 minutes prior to the formation of a mixture of alkoxo-β-diketonates metal, the resulting solution was dropwise applied to the Central part of the substrate which rotates with a speed of 100÷16000 rpm, or in the specified solution immerse the substrate with a speed of 0.1÷1000 mm/min at an angle vertically 0÷60°, after which withstand a substrate coated with a film of a solution of alkoxo-β-diketonates at 77÷523 K To stop the weight loss with the formation of a xerogel on the surface of the substrate, followed by crystallization of the oxide of the xerogel at 573÷1773 K.

2. The method according to claim 1, characterized in that as alcohols sources of alkoxo group used single - and multi-atom, linear and branched alcohols.

3. The method according to claim 1, characterized in that the alcohol solution additionally contains aliphatic and aromatic hydrocarbons and their halogen derivatives, ethers, aldehydes, ketones, organic is the cue acids and other organic solvents in quantities necessary to achieve the solution boiling point in the range of 368÷523 K.

4. The method according to claim 1, characterized in that the resulting alcoholic solution of alkoxo-β-diketonates metal pre-hydrolized by adding a water-alcohol solution at a molar ratio of water to metal 0,5÷10.

5. The method according to claim 1, characterized in that the coating film of the solution alkoxo-β-diketonates metal on a substrate is carried out at a solution temperature of 273 to 523 K and the temperature of the substrate 273÷1273 K.

6. The method according to claim 1, characterized in that the substrate material is chosen from a number of: silicon, silicon carbide, aluminum oxide.

7. The method according to claim 1, characterized in that the curing of the substrate coated with a film of a solution of alkoxo-β-diketonates to halting the loss of mass is carried out at pressures of 1·10-5÷1 ATM.

8. The method according to claim 1, characterized in that the crystallization of the oxide of the xerogel is carried out at pressures of 1·10-5÷1 ATM.

9. The method according to claim 1, characterized in that after the crystallization of the oxide of the xerogel spend additional annealing the substrate with the xerogel in a period of from 1 minute to 24 hours in an oxidizing or inert atmosphere at temperatures of 573÷1773 K.



 

Same patents:

FIELD: chemistry.

SUBSTANCE: invention relates to inorganic chemistry and specifically to producing sulphides of p-elements of group III, which are promising materials for semiconductor optoelectronic engineering and infrared optics. Sulphides of p-elements of group III are obtained by reacting sulphur and a corresponding p-element in an evacuated quartz ampoule, wherein the p-element is used in form of a corresponding iodide, synthesis is carried out in a two-section ampoule, initial components are placed in the bottom section which is heated to 250-400°C, after which the obtained sulphide is calcined at temperature not higher than 700°C. By conducting synthesis at sufficiently low temperature, the method considerably reduces contamination of the equipment with the material. The highest possible output of the product is 82-97%.

EFFECT: invention enables to obtain especially pure sulphides of p-elements of group III, in which content of transition metal impurities, according to mass spectrometric analysis, is not higher than 0,5 ppm wt.

2 cl, 1 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: invention relates to material science and metallurgy and specifically to methods of producing niobium or tantalum pentafluoride. The method involves reaction of niobium or tantalum metal with a fluorinating agent which is copper fluoride in ratio of not more than 4 moles of copper fluoride per mole of niobium or tantalum metal, heating the reactor to 500°C and thermal or vacuum distillation of the formed niobium or tantalum pentafluorides.

EFFECT: technology of producing niobium or tantalum pentafluoride, which does not require complex implementation and use of chemically active and highly toxic substances.

3 ex

FIELD: process engineering.

SUBSTANCE: invention relates to production of metal oxide materials, including metal hydroxides and/or metal oxides and catalysts. Proposed method comprises the following steps: dissolving metals in nitric acid to produce metal nitride and releasing NOX and water vapor. Hydrolysis of metal nitride solution by introducing compressed superheated water vapor in metal nitride solution to produce suspension of hydroxide suspension and acid gas. Main components of acid gas are NO2, NO, O2 and water vapor. Suspension filtration and drying to produce metal hydroxides and/or metal oxides. Further recovery of produced metal hydroxides and/or metal oxides and production of metal oxide catalyst in traditional process. Released gas NOX may be used for production of reusable nitric acid. Proposed device consists of system to produce metal salt solution, metal salt solution hydrolysis system, product production system, and system to produce and recycle nitric acid.

EFFECT: continuous production, closed circulation, no emissions, reduced costs.

17 cl, 1 tbl, 2 ex, 1 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to production of superconducting materials which are in liquid state which can be used as model liquids when designing superconductors. The oxide melt is obtained by melting fine powder of boric anhydride B2O3 and potassium carbonate K2CO3 in ratio: B2O3 - 99.3 %, K2O - 0.7 mol %. The melt is homogenised by thorough mixing with a platinum mixer. The oxide melt has properties of superconducting liquid at temperature of 770-1000°C.

EFFECT: invention enables to obtain material having superconducting liquid properties and widens the field of its use in liquid state for scientific research.

3 dwg, 2 tbl, 1 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing a middle distillate from hydrocarbon-containing energy sources. At least one hydrocarbon-containing energy source, optionally at least one catalyst and optionally at least one additive are fed into a reactor, which contains a process oil mixture, as raw material. A stream of the process oil mixture is output from the reactor and heated to operating temperature ranging from 150°C to 400°C, preferably from 350°C to 380°C. The stream of heated process oil mixture is fed into a degasifier. In the degasifier, the vaporous middle distillate is separated from the stream of heated process oil mixture. The stream of process oil mixture from the degasifier, from which the vaporous middle distillate has been removed, is returned to the process oil mixture in the reactor.

EFFECT: providing a method of producing a middle distillate from hydrocarbon-containing energy sources, which is cheap, requires low technological expenses and provides high process stability and high yield factor of calorific value of the energy sources used.

15 cl, 2 dwg

FIELD: nanotechnologies.

SUBSTANCE: invention relates to a technology for production of nanodispersed materials and may be used in chemical industry, electronics, powder metallurgy. The method includes mixing of a pure solution of a precursor with alcohols supporting burning, spraying and combustion of a mixture in flame, at the same time the pure solution of the precursor is a pure acidulous aqueous solution of titanium tetrachloride, and alcohol content in a sprayed mixture makes at least 80% (wt), water - not more than 15% (wt). The size of drops of the sprayed mixture makes not more than 2 mcm.

EFFECT: method makes it possible to produce pure powders of nanodispersed titanium dioxide (not containing admixtures of carbon and low content of 0,01-0,03% chloride-ion) with particle size of less than 100 nm and higher chemical and catalytic activity.

1 tbl, 12 ex

FIELD: chemistry.

SUBSTANCE: inventions can be used in systems of purification of exhaust gases of internal combustion engines. Composition for catalysts or catalyst substrates based on zirconium, cerium and yttrium oxides contains cerium oxide from 3% to 15%, yttrium oxide not more than 6%, if content of cerium oxide constitutes from more than 12% to 15% including; not more than 10%, if content of cerium oxide constitutes from more than 7% to 12% including; not more than 30%, if content of cerium oxide constitutes from 3 to 7% including; the remaining part - zirconium oxide. Composition can also contain oxide of rare earth element, selected from lanthanum, neodymium and praseodymium. Method of composition obtaining includes the following stages: contact of main compound and compound of zirconium, cerium, yttrium, other rare earth element, selected from lanthanum, neodymium and praseodymium, obtaining precipitate; heating sediment in liquid medium; addition of anionic SUS, non-ionogenic SUS, polyethylene glycol, carbonic acid and its salt, SUS such as carboxymethylated fatty alcohol ethoxylates; roasting obtained precipitate.

EFFECT: composition on invention after roasting at 1000°C for 4 h has degree of reduction, at least, 90% and specific surface, at least, 30 mІ/g.

14 cl, 5 tbl, 14 ex

FIELD: chemistry.

SUBSTANCE: invention can be used in light-current microelectronics. Chromium-copper-iron disulphide contains sulphur, chromium and copper, is a monocrystal and additionally contains iron. Components are in the following ratio in wt %: iron 0.99 - 0.31; chromium 28.93 - 28.95; copper 34.35 - 35.03; sulphur 35.71 - 35.73.

EFFECT: invention enables to obtain monocrystalline material, having magnetoresistance anisotropy at room temperature.

1 tbl, 2 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to chemistry. The method of producing functionalised nanoparticles of zinc oxide or sulphide or cadmium oxide or sulphide involves steps of: (a) preparing a ternary system of solvents containing a polar solvent, a nonpolar solvent and an intermediate solvent, which enables to mix all three components; (b) preparing a mixture of a transition metal salt and a ternary solvent; (c) preparing a mixture of an oxide or sulphide source and a ternary solvent; (d) preparing a mixture of a nonpolar finite coating agent and a nonpolar solvent; (e) mixing the prepared mixtures; (f) separating the obtained functionalised nanoparticles.

EFFECT: obtained ZnS or CdS nanoparticles with a nonpolar finite coating are used as UV light absorbents, in rubber compositions for vulcanisation.

21 cl, 6 dwg, 7 ex

FIELD: chemistry.

SUBSTANCE: invention relates to chemistry. The method of producing functionalised nanoparticles of zinc oxide or sulphide or cadmium oxide or sulphide involves steps of: (a) preparing a ternary system of solvents containing a polar solvent, a nonpolar solvent and an intermediate solvent, which enables to mix all three components; (b) preparing a mixture of a transition metal salt and a ternary solvent; (c) preparing a mixture of an oxide or sulphide source and a ternary solvent; (d) preparing a mixture of a nonpolar finite coating agent and a nonpolar solvent; (e) mixing the prepared mixtures; (f) separating the obtained functionalised nanoparticles.

EFFECT: obtained ZnS or CdS nanoparticles with a nonpolar finite coating are used as UV light absorbents, in rubber compositions for vulcanisation.

21 cl, 6 dwg, 7 ex

FIELD: medicine.

SUBSTANCE: invention may be used in medicine in producing preparations for a postoperative supporting therapy. What is involved is the high-temperature decomposition of methane on silicone or nickel substrate under pressure of 10-30 tor and a temperature of 1050-1150°C. The heating is conducted by passing the electric current through a carbon foil, cloth, felt or a structural graphite plate whereon the substrates are arranged. An analogous plate whereon a displacement potential from an external source is sent is placed above the specified plate. Nanodiamonds of 4 nm to 10 nm in size are deposited on the substrates.

EFFECT: higher effectiveness of the method.

1 dwg, 6 ex

FIELD: medicine.

SUBSTANCE: invention concerns an agent having an anti-stroke action and representing the amino acid glycine immobilised on the detonation-synthesised nanodiamond particles of 2-10 nm in size, and a method for preparing it.

EFFECT: agent possess high efficacy.

5 cl, 7 dwg, 12 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: invention relates to the field of polymer materials science and can be used in aviation, aerospace, motor transport and electronic industries. Nanotubes are obtained by a method of pyrolytic gas-phase precipitation in a magnetic field from carbon-containing gases with application of metals-catalysts in the form of a nanodisperse ferromagnetic powder, with the nanotubes being attached with their butt ends to ferromagnetic nanoparticles of metals-catalysts. Magnetic separation of the powder particles with grown on them nanotubes, used in obtaining a polymer-based composite material, is carried out. After filling with a polymer, a constant magnetic field is applied until solidification of the polymer takes place. The material contains carbon nanofibres and/or a gas-absorbing sorbent, for instance, silica gel, and/or siliporite, and/or polysorb as a filling agent.

EFFECT: increased mechanical strength, hardness, rigidity, heat- and electric conductivity.

4 cl, 3 ex

FIELD: physics.

SUBSTANCE: test object for calibrating microscopes is in form of groove structures whose walls have an inclined profile, a flat base and a different width on the surface and at the bottom. A constant angle between the side wall and the bottom plane is maintained for all elements. Linear dimensions of at least part of the elements differ from each other by a certain number of times, and linear dimensions of the largest element can be measured with high accuracy on calibrated measuring equipment used when taking measurements.

EFFECT: independence of measurements from ambient temperature and high accuracy of measuring length of sections which characterise the profile of a relief feature in a large wavelength range.

3 cl, 1 dwg

FIELD: medicine.

SUBSTANCE: invention concerns an antipsychotic agent representing the amino acid glycine immobilised on the detonation-synthesised nanodiamond particles of 2-10 nm in size, and a method for preparing it.

EFFECT: higher efficacy of the agent, and improved method for preparing it.

4 cl, 5 dwg, 6 tbl, 3 ex

FIELD: medicine.

SUBSTANCE: invention concerns an antioxidant representing the amino acid glycine immobilised on the detonation-synthesised nanodiamond particles of 2-10 nm in size.

EFFECT: higher efficacy.

4 cl, 5 dwg, 7 tbl, 3 ex

FIELD: medicine.

SUBSTANCE: invention concerns an antidepressant drug representing the amino acid glycine immobilised on the detonation-synthesised nanodiamond particles of 2-10 nm in size, and a method for preparing it.

EFFECT: antidepressant drug possesses higher efficacy.

4 cl, 7 dwg, 7 tbl, 2 ex

FIELD: medicine.

SUBSTANCE: invention concerns an anxiolytic representing the amino acid glycine immobilised on the detonation-synthesised nanodiamond particles of 2-10 nm in size, and a method for preparing it.

EFFECT: improving properties.

4 cl, 7 dwg, 6 tbl, 3 ex

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy, particularly, to chemical-thermal processing, in particular to cyclic gas nitration of alloys steels with application of nanotechnologies, and can be used for production steel dies for hot forming to be used at high temperatures. Heating is performed in the temperature range of T=550-590°C. Then, alternate feed of air and ammonia at air feed interval larger than that of ammonia in a cycle and with formation of water steam. Oxide films are produced at die surfaces and have electric charge to allow formation of the structure that consists of iron nitride nanoparticle ply and monolith play of cermet as oxycarbonitride. Then, curing is performed follows by cooling together with furnace. In particular cases, cycle interval makes 50 s at furnace volume making 0.5 l.

EFFECT: higher heat conductivity of die surface, deterioration and heat resistance.

2 cl, 1 tbl, 2 dwg, 6 ex

FIELD: chemistry.

SUBSTANCE: claimed invention relates to method of obtaining nanocellulose, which includes modification of cellulose fibres. method includes the following stages: i) processing cellulose fibres for, at least, five minutes with aqueous electrolyte-containing solution of amphoteric or anionic carboxymethylcellulose (CMC), where the temperature in the process of processing constitutes at least 50°C, and at least one of the following conditions is fulfilled: A) pH value of aqueous solution in the process of processing is in the interval about 1.5-4.5; or B) pH value of aqueous solution in the process of processing is higher than about 11; or C) concentration of electrolyte in aqueous solution is in the interval about 0.0001-0.5 M, if electrolyte has monovalent cations, or in the interval about 0.0001-0.1 M, if electrolyte has bivalent cations, ii) setting pH in the interval of pH values from about 5 to about 13 by application of basic and/or acidic liquid and iii) processing said material in mechanical crushing device and obtaining nanocellulose in such way. If amphoteric CMC is applied, at least 23.6 mg/g of CMC are added, and in case anionic CMC is applied, at least 61.6 mg/g of CMC are added.

EFFECT: application of method of nanocellulose production in accordance with claimed invention prevents clogging of mechanical devices.

13 cl, 7 dwg, 1 ex, 1 tbl

FIELD: electricity.

SUBSTANCE: method of MDM-cathode manufacturing is intended to increase a density of emission current and homogeneity of its distribution along the surface. A metal lower electrode based on a molybdenum film, then two layers of resistors where the pattern is generated by means of electron-beam lithography are deposited in sequence to a substrate, then a continuous film of molybdenum is sprayed. The nanofluidic structure is obtained by explosion of the resist mask in the form of pyramids with the base of 260 nm, vertex of 40 nm, height of 250 nm and density of 3·108 cm-2.

EFFECT: improvement in even distribution of emissive centres and the density of emission current.

2 dwg

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