Preparation method and application of magnetic nanometer catalyst loading nanogold

Abstract

The invention provides a preparation method and application of a magnetic nanometer catalyst loading nanogold. The preparation method comprises the steps of firstly fully dispersing magnetic nanometerparticles into ethyl alcohol, adding ammonium hydroxide and tetraethyl orthosilicate, stirring, and separating to obtain silicon-coated magnetic nanoparticles; then fully dispersing the silicon-coated magnetic nanoparticles into ethyl alcohol, adding a silane coupling agent with sulfydryl, stirring at room temperature, and separating to obtain sulfhydrylated magnetic nanoparticles; finally fullydispersing the sulfhydrylated magnetic nanoparticles into deionized water, adding a nanogold solution, stirring at the room temperature, and separating to obtain the magnetic nanometer catalyst loading the nanogold. During the preparation process, no complex organic reaction is involved, and the cheap silane coupling agent easy to get is used as a loading medium, so that the preparation method issimple and low-cost; the prepared magnetic nanometer catalyst has higher catalytic activity in p-nitrophenol reduction reaction, and can be recycled for multiple times.

Description

technical field

[0001] The invention relates to the technical field of catalysts, in particular to a preparation method and application of a magnetic nano-catalyst loaded with nano-gold. Background technique

[0002] As an important category of nanomaterials, magnetic nanoparticles not only have some macroscopic and microscopic properties of nanomaterials, but also have a series of other exclusive properties such as superparamagnetism, quantum size effect, and apparent magnetism, and are widely used in various fields in practice. . At present, there are many kinds of magnetic nanomaterials, among which the magnetic Fe 3 o 4 Nanoparticles are an important spinel-type ferrite, which has the advantages of simple preparation process, low price, non-toxic, non-polluting, etc., and is attracting more and more attention. Magnetic Fe 3 o 4 Nanoparticles have broad application prospects in the fields of gas-humidity sensing devices, high-density magnetic recording materials, nuc...

Examples

Embodiment 1

[0029] (1) The magnetic nanoparticles are prepared by a hydrothermal method, and then coated with a silicon dioxide layer. Disperse the magnetic nanoparticles in absolute ethanol to obtain a magnetic nanoparticle ethanol dispersion, add ammonia and tetraethyl orthosilicate in turn, wherein the volume ratio of the magnetic nanoparticles ethanol dispersion, ammonia and tetraethyl orthosilicate is 50: 1:0.5, stirred at room temperature for 12 hours to obtain silicon-coated magnetic nanoparticles.

[0030] (2) Disperse the silicon-coated magnetic nanoparticles in ethanol to obtain a silicon-coated magnetic nanoparticle dispersion (0.2 mg / mL). Ammonia water was added thereto and stirred for 15 min, and then 3-mercaptopropyltrimethoxysilane solution was added dropwise to the solution, wherein the volume ratio of the silicon-coated magnetic nanoparticle dispersion, ammonia water, and 3-mercaptopropyltrimethoxysilane was It is 50:0.5:0.25. After stirring at room temperature for 24 h...

Embodiment 2

[0034] (1) The magnetic nanoparticles are prepared by a hydrothermal method, and then coated with a silicon dioxide layer. Disperse the magnetic nanoparticles in absolute ethanol to obtain a magnetic nanoparticle ethanol dispersion, add ammonia and tetraethyl orthosilicate in turn, wherein the volume ratio of the magnetic nanoparticles ethanol dispersion, ammonia and tetraethyl orthosilicate is 50: 1:0.5, stirred at room temperature for 12 hours to obtain silicon-coated magnetic nanoparticles.

[0035](2) Disperse the silicon-coated magnetic nanoparticles in ethanol to obtain a silicon-coated magnetic nanoparticle dispersion (2.5 mg / mL). Ammonia water was added thereto and stirred for 15 min, and then 3-mercaptopropyltriethoxysilane solution was added dropwise to the solution, wherein silicon magnetic nanoparticle dispersion liquid, ammonia water, and 3-mercaptopropyltriethoxysilane were included. The volume ratio is 50:2.5:1.25. After stirring at room temperature for 24 hou...

Embodiment 3

[0039] (1) The magnetic nanoparticles are prepared by a hydrothermal method, and then coated with a silicon dioxide layer. Disperse the magnetic nanoparticles in absolute ethanol to obtain a magnetic nanoparticle ethanol dispersion, add ammonia and tetraethyl orthosilicate in turn, wherein the volume ratio of the magnetic nanoparticles ethanol dispersion, ammonia and tetraethyl orthosilicate is 50: 1:0.5. Stir at room temperature for 12 hours to obtain silicon-coated magnetic nanoparticles.

[0040] (2) Disperse the silicon-coated magnetic nanoparticles in ethanol to obtain a silicon-coated magnetic nanoparticle dispersion (5 mg / mL). Ammonia water was added thereto and stirred for 15 min, and then 3-mercaptopropyltrimethoxysilane solution was added dropwise to the solution, wherein the volume ratio of the silicon-coated magnetic nanoparticle dispersion, ammonia water, and 3-mercaptopropyltrimethoxysilane was It is 50:5:2.5. After stirring at room temperature for 24 hours, t...

technical field

[0001] The invention relates to the technical field of catalysts, in particular to a preparation method and application of a magnetic nano-catalyst loaded with nano-gold. Background technique

[0002] As an important category of nanomaterials, magnetic nanoparticles not only have some macroscopic and microscopic properties of nanomaterials, but also have a series of other exclusive properties such as superparamagnetism, quantum size effect, and apparent magnetism, and are widely used in various fields in practice. . At present, there are many kinds of magnetic nanomaterials, among which the magnetic Fe 3 o 4 Nanoparticles are an important spinel-type ferrite, which has the advantages of simple preparation process, low price, non-toxic, non-polluting, etc., and is attracting more and more attention. Magnetic Fe 3 o 4 Nanoparticles have broad application prospects in the fields of gas-humidity sensing devices, high-density magnetic recording materials, nuc...

Examples

Embodiment 1

[0029] (1) The magnetic nanoparticles are prepared by a hydrothermal method, and then coated with a silicon dioxide layer. Disperse the magnetic nanoparticles in absolute ethanol to obtain a magnetic nanoparticle ethanol dispersion, add ammonia and tetraethyl orthosilicate in turn, wherein the volume ratio of the magnetic nanoparticles ethanol dispersion, ammonia and tetraethyl orthosilicate is 50: 1:0.5, stirred at room temperature for 12 hours to obtain silicon-coated magnetic nanoparticles.

[0030] (2) Disperse the silicon-coated magnetic nanoparticles in ethanol to obtain a silicon-coated magnetic nanoparticle dispersion (0.2 mg / mL). Ammonia water was added thereto and stirred for 15 min, and then 3-mercaptopropyltrimethoxysilane solution was added dropwise to the solution, wherein the volume ratio of the silicon-coated magnetic nanoparticle dispersion, ammonia water, and 3-mercaptopropyltrimethoxysilane was It is 50:0.5:0.25. After stirring at room temperature for 24 h...

Embodiment 2

[0034] (1) The magnetic nanoparticles are prepared by a hydrothermal method, and then coated with a silicon dioxide layer. Disperse the magnetic nanoparticles in absolute ethanol to obtain a magnetic nanoparticle ethanol dispersion, add ammonia and tetraethyl orthosilicate in turn, wherein the volume ratio of the magnetic nanoparticles ethanol dispersion, ammonia and tetraethyl orthosilicate is 50: 1:0.5, stirred at room temperature for 12 hours to obtain silicon-coated magnetic nanoparticles.

[0035](2) Disperse the silicon-coated magnetic nanoparticles in ethanol to obtain a silicon-coated magnetic nanoparticle dispersion (2.5 mg / mL). Ammonia water was added thereto and stirred for 15 min, and then 3-mercaptopropyltriethoxysilane solution was added dropwise to the solution, wherein silicon magnetic nanoparticle dispersion liquid, ammonia water, and 3-mercaptopropyltriethoxysilane were included. The volume ratio is 50:2.5:1.25. After stirring at room temperature for 24 hou...

Embodiment 3

[0039] (1) The magnetic nanoparticles are prepared by a hydrothermal method, and then coated with a silicon dioxide layer. Disperse the magnetic nanoparticles in absolute ethanol to obtain a magnetic nanoparticle ethanol dispersion, add ammonia and tetraethyl orthosilicate in turn, wherein the volume ratio of the magnetic nanoparticles ethanol dispersion, ammonia and tetraethyl orthosilicate is 50: 1:0.5. Stir at room temperature for 12 hours to obtain silicon-coated magnetic nanoparticles.

[0040] (2) Disperse the silicon-coated magnetic nanoparticles in ethanol to obtain a silicon-coated magnetic nanoparticle dispersion (5 mg / mL). Ammonia water was added thereto and stirred for 15 min, and then 3-mercaptopropyltrimethoxysilane solution was added dropwise to the solution, wherein the volume ratio of the silicon-coated magnetic nanoparticle dispersion, ammonia water, and 3-mercaptopropyltrimethoxysilane was It is 50:5:2.5. After stirring at room temperature for 24 hours, t...

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