CN1166725C - A Method for Orderly Arranging Nanoparticles on the Surface of a Solid Substrate - Google Patents

Abstract

The present invention relates to a method for orderly arranging nanometer particles on the surface of a solid base, and the present invention belongs to the technical field of nanometers. The method of the present invention comprises the following specific steps: a chain-shaped organic molecule with a hydrophilic base group and a hydrophobic base group is dissolved in a volatile nonaqueous solvent; nanometer particles combined with the chain-shaped organic molecule with a hydrophilic base group and a hydrophobic base group are dispersed in a solution; pure water is used as a base solution, and the nonaqueous solution which contains the nanometer particles is spread in a Langmuir groove; film pressure of a monomolecular film of the nanometer particles on the water surface is controlled; the film is transferred onto the surface of the processed solid base by a vertical pulling method, which forms a Y-type LB film; the prepared nanometer particle film is processed in an annealing mode at high temperature or is irradiated with high-energy light rays; some organic molecules are dissociated and evaporated from a substrate; the nanometer particles are reserved on the base. The provided method has the characteristics of simple and easy operation, high transferring efficiency, ordered particle arrangement on the surface of the film, convenient adjustment of dimension and thickness, etc., the prepared film has few defects, and the method also has the advantages of wide application range and convenient generalization and application.

Description

A Method for Orderly Arranging Nanoparticles on the Surface of a Solid Substrate

technical field

The invention relates to a method for arranging nanoparticles, in particular to a method for orderly arranging nanoparticles on the surface of a solid substrate, belonging to the field of nanotechnology.

Background technique

Nanomaterials have become a current research hotspot due to their special properties and promising application prospects in electronics, magnetism, optics and catalysis. At present, nanoparticle materials can be prepared with high quality by a variety of methods, such as sol-gel method, photo-radiation redox method, electrochemical redox method, and sputtering method. However, with the development of nanoelectronic devices, it is increasingly required to quantitatively and orderly arrange nanoparticles on the surface of different solid substrates. LB technology has shown obvious advantages in this field due to its characteristics of quantitatively controllable film deposition thickness, no defects, and simple operation. In recent years, metal nanoparticles such as Ag, Au, and semiconductors such as CdS, ZnS, PbS, CdSe, and PbSe have been successfully prepared by using LB monomolecular film as a substrate to induce nucleation and growth of organic and inorganic nanoparticles. nanomaterial films. After literature search, it was found that the relevant Chinese invention patent, the patent number is 98103527.2, the authorized announcement number is CN 1075842C, and the name is "Formation of metal atom clusters smaller than 10 nanometers and two-dimensional ordered lattice of metal atoms on a monomolecular film Method", which is self-described as "a method for forming metal atom clusters and metal atom two-dimensional ordered lattices less than 10 nanometers on a monomolecular film, characterized in that the two-dimensional lattice of metal atoms is prepared by the single groove method: in the standard In the monomolecular film tank, use pure water as the base liquid, spread the monomolecular film of amphiphilic polymer or linear fatty acid or fatty amine dissolved in chloroform in the tank, and then press the monomolecular film to a constant pressure, After equilibration, the amphiphilic polymer needs to be irradiated with ultraviolet light to polymerize, or to lay the polymerized film directly. Then inject 5×10 ^-6 M to 5×10 ^-4 M metal salt or metal salt complex into the bottom solution Aqueous solution, so that the concentration of metal ions in the bottom solution is 5×10 ^-6 M to 5×10 ^-4 M; transfer the polymer film to the hydrophobic slide by horizontal pulling method or vertical pulling method, and immerse the slide into Rinse fully in pure water, then immerse in 10 ^-6 M to 10 ^-4 M reducing agent aqueous solution for reduction, and finally wash the slide, dry it with nitrogen, and form a two-dimensional metal atom less than 10 nanometers on the monomolecular film. Ordered lattice.", which discloses a method for forming a two-dimensional ordered lattice of metal clusters and metal atoms smaller than 10 nanometers on a monomolecular film. This method mainly uses an organic LB monomolecular film to induce metal ions or metal complex ions in the subphase solution, and it is necessary to reduce the metal ions or metal complex ions to metal particles. This kind of method consumes a lot of raw materials, the size of the particles in the prepared film is not easy to adjust, the operation is relatively complicated, and it is not easy to form a large-scale film and apply it.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies in the prior art and provide a method for orderly arranging nanoparticles on the surface of a solid substrate. The present invention uses a simple and practical method to realize the method for orderly arranging nanoparticles on the surface of a solid substrate , the obtained nanoparticle film is stable and orderly. The operation of monolayer and multilayer nanoscale particle ordered films on different solid substrates can be realized.

The present invention is achieved through the following technical solutions, and the concrete steps of the present invention are as follows:

a. Dissolving chain organic molecules with hydrophilic and hydrophobic groups in a volatile non-aqueous solvent. Nanoparticles combined with chain-like organic molecules with hydrophilic and hydrophobic groups are dispersed in the above solution.

b. Hydrophilic or hydrophobic treatment of the solid substrate.

c. In the Langmuir tank, with pure water as the bottom liquid, the above-mentioned non-aqueous solution containing nanoparticles is spread in the tank to control the membrane pressure of the nanoparticle monomolecular film on the water surface. The film was transferred to the treated solid substrate surface by vertical pulling method to form Y-shaped LB film.

d. Perform high-temperature annealing or high-energy light irradiation on the prepared nanoparticle film, some organic molecules dissociate and evaporate from the substrate, and the nanoparticles remain on the substrate.

In step a, the organic molecule used in the present invention is a chain organic molecule with hydrophilic and hydrophobic groups, and its hydrophilic group can be groups such as amino, carboxyl, and mercapto groups, and the number of carbon atoms is 14 to 10. twenty two. Changing the type of organic molecules and controlling the concentration of organic molecules in the non-aqueous solvent can change the distribution density and order of the nanoparticles on the surface of the film. The optimal concentration range of organic molecules in the process of orderly arrangement is between 1×10 ^-5 ~ 6×10 ^-4 M, and the concentration of nanoparticles in non-aqueous solvent is between 1 ~ 10 mg/ml. When arranging nano-alloy particles, it is best to use a mixed solution of two organic molecules containing amino and carboxyl groups, and the ratio of the amount of the two organic molecules mixed is controlled between 0.1:1 and 10:1. . The volatile non-aqueous solvent used in the present invention is hexane, chloroform, toluene. The size of the arranged nanoparticles in the present invention is 1-30 nanometers, and the arranged nanoparticles include metal particles, alloy particles and metal oxide particles. Metals can be transition metal elements such as iron, cobalt, nickel, platinum, etc. The alloy particles arranged are mainly iron-platinum, cobalt-platinum, and cobalt-nickel alloys, and the metal oxide particles are mainly cobalt oxide, nickel oxide, titanium oxide, and iron oxide. , tin oxide, zinc oxide.

In step b, the solid substrates used in the present invention are mainly glass flakes, silicon flakes and silicon flakes with surface oxidation.

In step c, the membrane pressure is controlled between 15-30 mN/m. After the non-aqueous solution of nanoparticles is spread on the water surface, it needs to stand still for more than 30 minutes to make the non-aqueous solvent fully volatilize. After pushing the film to the required pressure, it is balanced at a constant pressure for 0.5-2 hours, and the film-drawing speed is maintained at 1-10mm/ min.

In step d, in order to stably arrange the nanoparticles on the surface of the solid substrate, the present invention takes high-temperature annealing and high-energy light treatment on the film after film formation. Among them, the metal and alloy particle films are annealed at high temperature in an inert gas environment. The annealing temperature of the film is controlled at 500-650°C, and kept at this temperature for 1-60 minutes. The nano-metal oxide particle film is used in air or oxygen. High-temperature annealing in the atmosphere or the method of high-energy light irradiation. According to the arrangement of the nano metal oxide particles and the used organic molecules, the time of annealing and light irradiation is also different. A more suitable temperature for annealing is 300-650° C., the temperature is maintained for 1-60 minutes, and the high-energy light irradiation time is maintained for 1-40 minutes.

The present invention has substantive features and remarkable progress. The invention utilizes the Langmuir-Blodgett technique to prepare a nanoparticle film with uniform and controllable thickness. In the single-layer film, the nanoparticle can be arranged in a two-dimensional order. Since the prepared nanoparticles are used as raw materials in the film forming process, the types of nanoparticles that can be arranged are expanded, and the particle size on the surface of the film is conveniently adjustable and easy to control. At the same time, the ordered arrangement of nanoparticles can be conveniently realized by adjusting the chain length and concentration of organic molecules dispersed in non-aqueous solvents. The arranged ordered film can maintain high stability after annealing or light treatment, and the stability time exceeds 72 hours. In addition, the raw materials are greatly saved because the nanoparticles are dispersed in a non-aqueous solvent and spread on the water surface. The method provided by the invention has the characteristics of simplicity, high transfer efficiency, convenient and adjustable particle size and thickness on the surface of the film, and few defects in the prepared film. The method has a wide application range and is convenient for popularization and application.

Detailed ways

Provide following embodiment in conjunction with content of the present invention:

Embodiment 1 Arrangement of iron-platinum nano-alloy particle film

After step a of the present invention, spread 450 μl of hexane solution containing 4 nanometer iron-platinum alloy particles with a concentration of 2.5 mg/ml and a total organic molecule concentration of 2×10 ^-4 M on the water surface, and after equilibrating for 30 minutes, the The film was pressed to a constant pressure of 20mN/m, and after equilibrating for 30 minutes, the film was transferred to a glass slide by vertical pulling method, and the film pulling speed was kept at 2mm/min, washed and dried. Multilayer films with controllable thickness can be obtained by repeating the pulling process. The obtained film is heated to 600° C. and annealed for 10 minutes under the protection of nitrogen to obtain a monolayer film of iron-platinum nano-alloy particles arranged in a square order.

Embodiment 2 Arrangement of iron nanoparticle film

Spread 350 μl of chloroform solution containing 10nm iron nanoparticles at a concentration of 8 mg/ml and an organic molecule concentration of 1×10 ^-4 M on the water surface. After equilibrating for 30 minutes, press the membrane to a constant pressure of 28 mN/m, and equilibrate for 30 minutes. After 10 minutes, the film was transferred to a glass slide by vertical pulling method, the film pulling speed was kept at 8mm/min, washed and dried. Multilayer films with controllable thickness can be obtained by repeating the pulling process. The obtained film was heated to 500° C. and annealed for 20 minutes under the protection of nitrogen to obtain a monolayer film of iron nanoparticles arranged in a hexagonal order.

Embodiment 3 Arrangement of titanium oxide nanoparticle film

Spread 400μl of toluene solution with 30nm titanium oxide nanoparticle concentration of 5mg/ml and organic molecule concentration of 4×10 ^-4 M on the water surface. After equilibrating for 30 minutes, press the membrane to a constant pressure of 15mN/m, and equilibrate for 60 After 10 minutes, the film was transferred to a glass slide by vertical pulling method, the film pulling speed was kept at 5mm/min, washed and dried. Multilayer films with controllable thickness can be obtained by repeating the pulling process. The obtained thin film is subjected to high-energy light irradiation for 5 minutes, and a single-layer and multi-layer ordered thin film of titanium oxide nanoparticles can be obtained.

Claims (10)

1. the method for a solid substrate surface ordered arrangement nano particle is characterized in that, the present invention includes following steps:

A. will have hydrophilic and chain organics molecule hydrophobic grouping and be dissolved in the non-aqueous volatile solvent, will with the chain organics molecule bonded nanoparticulate dispersed that has hydrophilic and hydrophobic grouping in above-mentioned solution,

B. solid substrate is carried out hydrophilic or hydrophobic treatment,

C. in the Langmuir groove, with the pure water is end liquid, the above-mentioned non-aqueous solution that contains nano particle is spread in the groove mould of control water surface nano particle monomolecular film, transfer to the solid substrate surface of handling with film via vertical pulling and form Y-type LB film

D. prepared nanometer particle film is carried out high temperature annealing or high energy irradiate light, some organic molecules dissociate, and evaporate from substrate, and nano particle is retained in the substrate.

2. the method for this solid substrate according to claim 1 surface ordered arrangement nano particle, it is characterized in that, employed organic molecule is a kind of hydrophilic and chain organics molecule hydrophobic grouping of having in step a, its hydrophilic radical is amino, carboxyl, mercapto groups, carbonatoms 14～22.

3. the method for this solid substrate according to claim 2 surface ordered arrangement nano particle is characterized in that the organic molecule concentration range is 1 * 10 ^-5～6 * 10 ^-4Between the M, the concentration in non-aqueous solvent of nano particle is between 1～10mg/ml.

4. the method for this solid substrate according to claim 3 surface ordered arrangement nano particle, it is characterized in that, use the mixing solutions of two organic molecular species that contain amino and carboxylic group respectively when arranging the Nanoalloy particle, the ratio of blended amount of substance is between 0.1: 1～10: 1.

5. the method for this solid substrate according to claim 3 surface ordered arrangement nano particle is characterized in that non-aqueous solvent is imitative, the toluene of hexane, oxygen.

6. the method for this solid substrate according to claim 1 surface ordered arrangement nano particle, it is characterized in that, the nano particle of being arranged in step a is of a size of 1～30 nanometer, the nano particle of being arranged comprises metallic particles, alloying pellet and metal oxide particle, metal is transition metal iron, cobalt, nickel, platinum element, the alloying pellet of being arranged is iron platinum, cobalt platinum, cobalt-nickel alloy, and metal oxide particle is cobalt oxide, nickel oxide, titanium oxide, ferric oxide, stannic oxide, zinc oxide.

7. the method for this solid substrate according to claim 1 surface ordered arrangement nano particle is characterized in that the solid substrate in step b is the silicon chip of sheet glass, silicon chip and surface oxidation.

8. the method for this solid substrate according to claim 1 surface ordered arrangement nano particle, it is characterized in that, mould is controlled between 15～30mN/m among the step c, the non-aqueous solution of nano particle is sprawled need be static more than 30 minutes after the water surface, so that non-aqueous solvent fully volatilizees, push away film behind the required pressure under constant pressure balance 0.5～2 hour, membrane speed remains 1～10mm/min.

9. the method for this solid substrate according to claim 1 surface ordered arrangement nano particle, it is characterized in that, when high temperature annealing of in the steps d film being taked and high energy photo-irradiation treatment, wherein metal and alloying pellet film adopt the method for high temperature annealing in inert gas environment, the annealing temperature of film is controlled at 500～650 ℃, and keeps under this temperature 1～60 minute.

10. the method for this solid substrate according to claim 9 surface ordered arrangement nano particle, it is characterized in that, the nano-metal-oxide particle film adopts in air or oxygen atmosphere high temperature annealing or adopts the method for high energy irradiate light, annealing temperature is 300～650 ℃, temperature kept 1～60 minute, and high energy light irradiation time kept 1～40 minute.