A method for preparing gold-coated nano-magnetic particles for preparing magnetic liquids

Abstract

A method for preparing gold-coated nano-magnetic particles for preparing magnetic liquids, the method comprising: chloroauric acid and sodium citrate at a mass ratio of ferric oxide nano-magnetic particles to chloroauric acid of 1:10 to 1:0.5 The mass ratio of 1:36.9~1:7.4 or the mass ratio of chloroauric acid and hydroxylamine hydrochloride 1:5.6~1:2 is weighed and prepared; the solution is made according to the weighed chloroauric acid, hydroxylamine hydrochloride and sodium citrate. Dissolve ferric oxide nano-magnetic particles in absolute ethanol and disperse completely by ultrasonic. Add 3-aminopropyltriethoxysilane and iron ferric oxide nano-magnetic particles, the ratio of volume to mass is 1:1-4:1, and continue to sonicate. Add the configured chloroauric acid solution and ultrasonicate for 1h. Adding sodium citrate solution and hydroxylamine hydrochloride solution, ultrasonication for 6 hours, separation, washing, ultrasonic cleaning with dilute hydrochloric acid for 1 hour, separation and drying, to prepare gold-coated nano-magnetic particles. The corrosion resistance of magnetic fluids prepared from gold-coated particles is enhanced.

Description

technical field

[0001] The invention belongs to the field of nano magnetic materials and relates to a preparation method of gold-coated nano magnetic particles used for preparing magnetic liquids. Background technique

[0002] Magnetic liquid is a new type of nano functional material. It is a stable colloidal system composed of nano-scale magnetic particles uniformly dispersed in the carrier liquid. Because it has both magnetic properties and liquid fluidity, as well as its superparamagnetic properties, it has a series of unique excellent properties that other conventional materials and new materials do not have, and can be widely used in seals, bearings , sensors, lubrication, grinding, damping, electronic technology, information technology, biomedicine and other fields.

[0003] At present, many units have studied the preparation of magnetic liquids and made great progress. However, due to the sensitivity of ferric iron tetroxide nanoparticles in magnetic liquids to acid...

Examples

Embodiment 1

[0028] A method for preparing a gold-coated nano-magnetic particle for preparing a magnetic liquid, the preparation method comprising the following steps:

[0029] In step 1, the mass ratio of ferric iron tetroxide nano-magnetic particles to chloroauric acid is 1:10, and the mass ratio of chloroauric acid to sodium citrate is 1:36.9.

[0030] Weigh 0.1 g of dried iron ferric oxide nano-magnetic particles, 1 g of chloroauric acid, and 36.9 g of sodium citrate.

[0031] The chloroauric acid 1g that weighs is mixed with molar concentration and is 80mmol / L chloroauric acid solution.

[0032] The sodium citrate 36.9g that will take by weighing is mixed with molar concentration and is 2.5mol / L sodium citrate solution.

[0033] Step 2, dissolving 0.1 g of iron ferric oxide nano-magnetic particles weighed in absolute ethanol, and ultrasonically dispersing in an ultrasonic cleaner until the magnetic particles are completely dispersed.

[0034] Step 3, add 0.4ml of 3-aminopropyltrieth...

Embodiment 2

[0038] A method for preparing a gold-coated nano-magnetic particle for preparing a magnetic liquid, the preparation method comprising the following steps:

[0039] In step 1, the mass ratio of ferric iron tetroxide nano-magnetic particles to chloroauric acid is 1:0.5, and the mass ratio of chloroauric acid to sodium citrate is 1:7.4.

[0040] Weigh 1 g of dried iron ferric oxide nano-magnetic particles, 0.5 g of chloroauric acid, and 3.7 g of sodium citrate.

[0041] The chloroauric acid 0.5g that weighs is mixed with molar concentration and is 48.6mmol / L chloroauric acid solution.

[0042] The sodium citrate 3.7g that takes by weighing is formulated and made into molar concentration and is 1mol / L sodium citrate solution.

[0043] Step 2, dissolving 1 g of iron ferric oxide nano-magnetic particles weighed in absolute ethanol, and ultrasonically dispersing in an ultrasonic cleaner until the magnetic particles are completely dispersed.

[0044] Step 3, add 1ml 3-aminopropyltri...

Embodiment 3

[0048] A method for preparing a gold-coated nano-magnetic particle for preparing a magnetic liquid, the preparation method comprising the following steps:

[0049] Step 1: The mass ratio of iron ferric oxide nano-magnetic particles to chloroauric acid is 1:0.5, and the mass ratio of chloroauric acid to hydroxylamine hydrochloride is 1:5.6.

[0050] Weigh 1 g of dried iron ferric oxide nano-magnetic particles, 0.5 g of chloroauric acid, and 2.8 g of hydroxylamine hydrochloride.

[0051] The chloroauric acid 0.5g that weighs is mixed with molar concentration and is 48.6mmol / L chloroauric acid solution.

[0052] The hydroxylamine hydrochloride 2.8g that weighed is formulated and made molar concentration and is 0.1mol / L hydroxylamine hydrochloride solution.

[0053] Step 2, dissolving 1 g of iron ferric oxide nano-magnetic particles weighed in absolute ethanol, and ultrasonically dispersing in an ultrasonic cleaner until the magnetic particles are completely dispersed.

[0054] ...

technical field

[0001] The invention belongs to the field of nano magnetic materials and relates to a preparation method of gold-coated nano magnetic particles used for preparing magnetic liquids. Background technique

[0002] Magnetic liquid is a new type of nano functional material. It is a stable colloidal system composed of nano-scale magnetic particles uniformly dispersed in the carrier liquid. Because it has both magnetic properties and liquid fluidity, as well as its superparamagnetic properties, it has a series of unique excellent properties that other conventional materials and new materials do not have, and can be widely used in seals, bearings , sensors, lubrication, grinding, damping, electronic technology, information technology, biomedicine and other fields.

[0003] At present, many units have studied the preparation of magnetic liquids and made great progress. However, due to the sensitivity of ferric iron tetroxide nanoparticles in magnetic liquids to acid...

Examples

Embodiment 1

[0028] A method for preparing a gold-coated nano-magnetic particle for preparing a magnetic liquid, the preparation method comprising the following steps:

[0029] In step 1, the mass ratio of ferric iron tetroxide nano-magnetic particles to chloroauric acid is 1:10, and the mass ratio of chloroauric acid to sodium citrate is 1:36.9.

[0030] Weigh 0.1 g of dried iron ferric oxide nano-magnetic particles, 1 g of chloroauric acid, and 36.9 g of sodium citrate.

[0031] The chloroauric acid 1g that weighs is mixed with molar concentration and is 80mmol / L chloroauric acid solution.

[0032] The sodium citrate 36.9g that will take by weighing is mixed with molar concentration and is 2.5mol / L sodium citrate solution.

[0033] Step 2, dissolving 0.1 g of iron ferric oxide nano-magnetic particles weighed in absolute ethanol, and ultrasonically dispersing in an ultrasonic cleaner until the magnetic particles are completely dispersed.

[0034] Step 3, add 0.4ml of 3-aminopropyltrieth...

Embodiment 2

[0038] A method for preparing a gold-coated nano-magnetic particle for preparing a magnetic liquid, the preparation method comprising the following steps:

[0039] In step 1, the mass ratio of ferric iron tetroxide nano-magnetic particles to chloroauric acid is 1:0.5, and the mass ratio of chloroauric acid to sodium citrate is 1:7.4.

[0040] Weigh 1 g of dried iron ferric oxide nano-magnetic particles, 0.5 g of chloroauric acid, and 3.7 g of sodium citrate.

[0041] The chloroauric acid 0.5g that weighs is mixed with molar concentration and is 48.6mmol / L chloroauric acid solution.

[0042] The sodium citrate 3.7g that takes by weighing is formulated and made into molar concentration and is 1mol / L sodium citrate solution.

[0043] Step 2, dissolving 1 g of iron ferric oxide nano-magnetic particles weighed in absolute ethanol, and ultrasonically dispersing in an ultrasonic cleaner until the magnetic particles are completely dispersed.

[0044] Step 3, add 1ml 3-aminopropyltri...

Embodiment 3

[0048] A method for preparing a gold-coated nano-magnetic particle for preparing a magnetic liquid, the preparation method comprising the following steps:

[0049] Step 1: The mass ratio of iron ferric oxide nano-magnetic particles to chloroauric acid is 1:0.5, and the mass ratio of chloroauric acid to hydroxylamine hydrochloride is 1:5.6.

[0050] Weigh 1 g of dried iron ferric oxide nano-magnetic particles, 0.5 g of chloroauric acid, and 2.8 g of hydroxylamine hydrochloride.

[0051] The chloroauric acid 0.5g that weighs is mixed with molar concentration and is 48.6mmol / L chloroauric acid solution.

[0052] The hydroxylamine hydrochloride 2.8g that weighed is formulated and made molar concentration and is 0.1mol / L hydroxylamine hydrochloride solution.

[0053] Step 2, dissolving 1 g of iron ferric oxide nano-magnetic particles weighed in absolute ethanol, and ultrasonically dispersing in an ultrasonic cleaner until the magnetic particles are completely dispersed.

[0054] ...

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