CN114682791A - Gold nanoparticle dispersion, gold nanoparticles and preparation method thereof - Google Patents
Gold nanoparticle dispersion, gold nanoparticles and preparation method thereof Download PDFInfo
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- CN114682791A CN114682791A CN202210335727.XA CN202210335727A CN114682791A CN 114682791 A CN114682791 A CN 114682791A CN 202210335727 A CN202210335727 A CN 202210335727A CN 114682791 A CN114682791 A CN 114682791A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/16—Making metallic powder or suspensions thereof using chemical processes
- B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
- B22F9/24—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from liquid metal compounds, e.g. solutions
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- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
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Abstract
The invention provides a gold nanoparticle dispersion and a preparation method of gold nanoparticles, which effectively solve the problems of complex preparation process, low product purity and complex post-treatment in the prior art, obtain the gold nanoparticle dispersion by heating a gold ion solution containing an alcoholic solvent, and obtain high-purity gold nanoparticle powder by simple filtering and washing steps. The obtained gold nanoparticles can be used as a function to be correspondingly used in electronic slurry, and meanwhile, have wide application prospects in the fields of catalysis, biomedicine and the like.
Description
Technical Field
The invention relates to the technical field of gold nano materials, in particular to gold nano particles, a gold nano dispersion and a preparation method thereof.
Technical Field
The gold nanoparticles have unique optical, thermal, electrical and stability, and can be widely applied to the fields of catalysis, electronics, medicine, sensing and the like.
At present, the synthesis method of the gold nanoparticles is mainly divided into a physical method and a chemical method. The physical method is to prepare gold blocks into nano-scale small particles by adopting high physical energy. The main physical methods include ball milling, gas phase, arc, metal vapor solvent, thermal decomposition, etc., but the existing physical methods all have the problems of low yield, high equipment cost and large energy consumption. The chemical method is mainly to reduce gold ions in the gold salt into gold powder through oxidation-reduction reaction. The main chemical methods include aqueous phase redox method, Brust method, gold growth method, template method, chemical synthesis method, electrochemical method, photochemical method, etc.
However, the existing chemical method still has many limitations, and although the form of the gold nano powder can be regulated and controlled by adding a large amount of surfactant and reducing agent, a lot of post-treatment processes are brought, the production process is complex, the impurity content of the product is high, and how to develop the preparation method of the gold nano powder with simpler preparation process and high product purity is a technical problem at present.
Disclosure of Invention
In view of the above, the invention provides a gold nanoparticle dispersion and a gold nanoparticle preparation method aiming at the technical problems of complex preparation process, low product purity and complex post-treatment of gold nanoparticle powder, and solves the problems of complex preparation process, low product purity and complex post-treatment in the prior art.
One aspect of the invention provides a method of preparing a gold-containing nanoparticle dispersion, comprising:
preparing a gold ion solution containing an alcohol solvent;
and heating the gold ion solution containing the alcoholic solvent to obtain the gold-containing nanoparticle dispersion.
Another aspect of the present invention also provides a method of preparing gold nanoparticles, comprising:
preparing a gold ion solution containing an alcohol solvent;
heating the gold ion solution containing the alcoholic solvent to obtain a gold nanoparticle-containing dispersion;
and separating the gold-containing nanoparticle dispersion to obtain gold nanoparticles.
According to the method for preparing the gold-containing nanoparticle dispersion or the gold nanoparticles, provided by the invention, the alcohol solvent is at least one of ethylene glycol, isopropanol, n-propanol and tert-butanol.
According to the method for preparing a gold-containing nanoparticle dispersion or for preparing gold nanoparticles provided by the invention, the alcoholic solvent-containing gold ion solution does not contain other reducing agents. The reducing agent is a component which can react with gold ions to reduce the gold ions into gold. The reducing agent includes, but is not limited to, phosphorus, trisodium citrate, sodium borohydride, hexadecylaniline, polyethylene glycol, polyaniline and dimethylamine borane, citric acid, ascorbic acid, and the like.
According to the method for preparing the gold-containing nanoparticle dispersion or the gold nanoparticles, the step of preparing the gold ion solution containing the alcoholic solvent comprises the step of adding one gold ion raw material of gold chlorate and gold fulminate into the alcoholic solvent for mixing to obtain the gold ion solution containing the alcoholic solvent.
According to the method for preparing the gold-containing nanoparticle dispersion or the gold nanoparticles, the mass ratio of the gold ion raw material to the alcohol solvent is 0.02-0.5.
According to the method for preparing a gold-containing nanoparticle dispersion or gold nanoparticles provided by the present invention, in some embodiments, the mass ratio of the gold ion raw material to the alcohol solvent is 0.02; in some embodiments, the mass ratio of the gold ion source to the alcohol solvent is 0.05; in some embodiments, the mass ratio of the gold ion source to the alcohol solvent is 0.1; in some embodiments, the mass ratio of the gold ion source to the alcohol solvent is 0.2; in some embodiments, the mass ratio of the gold ion source to the alcohol solvent is 0.3; in some embodiments, the mass ratio of the gold ion source to the alcohol solvent is 0.5.
According to the method for preparing gold-containing nanoparticle dispersion or gold nanoparticles provided by the invention, in some preferred embodiments, the gold ion raw material is gold fulminate, the alcohol solvent is isopropanol, and the mass ratio of the gold ion raw material to the alcohol solvent is 0.05-0.3.
According to the method for preparing gold-containing nanoparticle dispersion or gold nanoparticles provided by the present invention, the step of heating the alcohol solvent-containing gold ion solution comprises heating the alcohol solvent-containing gold ion solution to 85-150 ℃.
According to the method for preparing gold-containing nanoparticle dispersion or gold nanoparticles provided by the invention, the step of heating the gold ion solution containing the alcoholic solvent further comprises the step of heating the gold ion solution containing the alcoholic solvent to 85-150 ℃ in a reaction kettle, and then reacting for 1-6 h.
It will be appreciated that a portion of the alcoholic solvent has a boiling point below 150 ℃ and may be heated to the corresponding temperature by means of pressure in order to bring the temperature to the reaction temperature. In some embodiments, the pressurization is by pressurizing the reaction in a reaction vessel.
According to the method for preparing gold-containing nanoparticle dispersion or gold nanoparticles provided by the present invention, in some preferred embodiments, the step of heating the alcohol solvent-containing gold ion solution comprises reacting the alcohol solvent-containing gold ion solution for 2 to 4 hours after heating the alcohol solvent-containing gold ion solution to 90 to 120 ℃.
According to the method for preparing the gold nanoparticles, provided by the invention, the average particle size of the gold nanoparticles is 200-500 nm.
According to the method for preparing gold nanoparticles provided by the present invention, the step of separating the gold-containing nanoparticle dispersion comprises separating the gold nanoparticles from the gold-containing nanoparticle dispersion by at least one of filtration, sedimentation or centrifugation.
According to the method for preparing gold nanoparticles provided by the invention, after the gold nanoparticles are separated from the gold-containing nanoparticle dispersion through at least one of filtration, sedimentation or centrifugation, the method further comprises washing the gold nanoparticles obtained in the previous step for 3-5 times by using deionized water or ethanol, and drying to obtain dried gold nanoparticles.
It will be appreciated that drying is a commonly used means in the art of material preparation for removing moisture from a product, and that conventional drying methods include at least one of vacuum drying, freeze drying, natural drying, heat drying and forced air drying.
According to the method for preparing the gold nanoparticles, provided by the invention, the water content of the dried gold nanoparticles is lower than 0.1%.
According to the method for preparing gold-containing nanoparticle dispersion or preparing gold nanoparticles provided by the invention, the burning loss value of the dried gold nanoparticles is 0.1-0.2%.
It will be appreciated that the burn-out value of the product may reflect the level of organic impurities in the final product. The higher the burn-out value, the higher its organic content. The lower the burn-out value, the higher the purity of the product. The preparation method can obtain the gold nanoparticle product with the burning loss value lower than 0.2% through simple purification steps, and is difficult to realize by the technical route disclosed by the prior art.
The invention also provides a gold nanoparticle dispersion prepared by the method for preparing the gold-containing nanoparticle dispersion.
The invention also provides a gold nanoparticle, which is prepared by the method for preparing the gold nanoparticle.
Compared with the prior art, the invention has the beneficial effects that:
1. according to the method for preparing the gold-containing nanoparticle dispersion or the gold nanoparticles, a soluble or insoluble gold source is adopted in the preparation process, and the gold source is not selective.
2. The method has the advantages that no other auxiliary agent or reducing agent is added in the reaction process, the organic solvent serves as both the solvent and the reducing agent, the process is simple, errors caused by other manual operations are reduced, the obtained gold nanoparticles have fewer impurities, the purity is high, the structure is uniform, the gold nanoparticles can be better used in electronic slurry as a functional phase, and the post-treatment steps can be reduced.
3. The method can regulate and control the particle size of the prepared gold powder by adjusting conditions such as reaction temperature, reaction time and the like, can obtain gold powder particles with different shapes so as to meet different use requirements, and has good reaction result reproducibility.
4. After the organic solvent after the reaction is recovered, the organic solvent can be continuously used through simple vacuum distillation recovery and purification, so that the cost is saved, and the pollution of the organic solvent to the environment is avoided.
Drawings
FIG. 1 is a photograph of a gold-containing nanoparticle dispersion obtained in example 1 of the present invention;
FIG. 2 is a scanning electron micrograph of gold nanoparticles obtained in example 1 of the present invention;
FIG. 3 is a photograph of gold nanoparticles obtained in example 1 of the present invention.
Detailed Description
The following describes the embodiments of the present invention in detail. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.
The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual points, and between the individual points may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein.
Throughout the text, h represents the time unit "hour" and "/" represents "or" unless otherwise specified. All the components and the content ratios are mass ratios unless otherwise specified.
All reagent starting materials are commercially available in the following examples.
Example 1
This example method of preparing a gold-containing nanoparticle dispersion includes the steps of:
step 1, dissolving 2.55g of chloroauric acid in 50g of isopropanol, fully stirring and standing, and precipitating the chloroauric acid at the bottom;
and 2, transferring the obtained solution and precipitate into a reaction kettle, setting the temperature of an oven to be 150 ℃, and preserving the heat for 6 hours to obtain the gold-containing nanoparticle dispersion, wherein the photo of the gold-containing nanoparticle dispersion is shown in figure 1.
The method for preparing gold nanoparticles of the embodiment comprises the following steps:
the method of the embodiment is adopted to prepare gold-containing nanoparticle dispersoid, the gold-containing nanoparticle dispersoid is subjected to suction filtration, reaction isopropanol is recovered, a solid product obtained by suction filtration is washed with deionized water for 2 times and then washed with ethanol for 3 times, surface impurities are removed, and the gold nanoparticles are obtained, wherein a scanning electron microscope image of the gold nanoparticles is shown in fig. 2, and a macroscopic photograph is shown in fig. 3. Drying the gold nanoparticles in a 60 ℃ blast oven for 100min to obtain gold powder with the particle size D90 of 220 nm. The yield of the product is 69 percent, and the ablation rate of the product at 200 ℃ is 0.13 percent.
Example 2
This example method of preparing a gold-containing nanoparticle dispersion includes the steps of:
step 1, dissolving 2.55g of gold fulminate in 50g of isopropanol, and fully stirring and dispersing to obtain a clear gold fulminate solution;
and 2, transferring the obtained clear solution into a reaction kettle, setting the temperature of an oven to be 150 ℃, and preserving the heat for 6 hours to obtain the gold-containing nanoparticle dispersion.
The method for preparing gold nanoparticles of the embodiment comprises the following steps:
the method of the embodiment is adopted to prepare the gold-containing nanoparticle dispersion, the gold nanoparticle dispersion is subjected to suction filtration, reaction isopropanol is recovered, a solid product obtained by suction filtration is washed with deionized water for 2 times and then washed with ethanol for 3 times, and surface impurities are removed to obtain the gold nanoparticles. Drying the gold nanoparticles in a 60 ℃ blast oven for 100min to obtain gold powder, wherein the particle size D90 is 377 nm. The yield of the product is 80 percent, and the ablation rate of the product at 200 ℃ is 0.10 percent.
Example 3
This example method of preparing a gold-containing nanoparticle dispersion includes the steps of:
step 1, dissolving 3.5g of bronsted acid in 50g of isopropanol, and fully stirring and dispersing to obtain a clear bronsted acid solution;
and 2, transferring the obtained clear solution into a reaction kettle, setting the temperature of an oven to be 150 ℃, and preserving the heat for 6 hours to obtain the gold-containing nanoparticle dispersion.
The method for preparing gold nanoparticles of the embodiment comprises the following steps:
the method of the embodiment is adopted to prepare the gold-containing nanoparticle dispersion, the gold nanoparticle dispersion is subjected to suction filtration, reaction isopropanol is recovered, a solid product obtained by suction filtration is washed with deionized water for 2 times and then washed with ethanol for 3 times, and surface impurities are removed to obtain the gold nanoparticles. And drying the gold nanoparticles in a 60 ℃ blast oven for 100min to obtain gold powder with the particle size D90 of 251 nm. The yield of the product is 84 percent, and the ablation rate of the product at 200 ℃ is 0.10 percent.
Example 4
This example method of preparing a gold-containing nanoparticle dispersion includes the steps of:
step 1, dissolving 2.55g of chloroauric acid in 50g of isopropanol, fully stirring and standing, and precipitating the chloroauric acid at the bottom;
and 2, transferring the obtained solution and precipitate into a reaction kettle, setting the temperature of an oven to be 120 ℃, and preserving the temperature for 4 hours to obtain the gold-containing nanoparticle dispersion.
The method for preparing gold nanoparticles of the present embodiment includes the following steps:
the method of the embodiment is adopted to prepare the gold-containing nanoparticle dispersion, the gold nanoparticle dispersion is subjected to suction filtration, reaction isopropanol is recovered, a solid product obtained by suction filtration is washed with deionized water for 2 times and then washed with ethanol for 3 times, and surface impurities are removed to obtain the gold nanoparticles. Drying the gold nanoparticles in a 60 ℃ blast oven for 100min to obtain gold powder with the particle size D90 of 410 nm. The yield of the product is 68 percent, and the ablation rate of the product at 200 ℃ is 0.10 percent.
Comparative example 1
The method of preparing gold nanoparticles of this comparative example includes the steps of:
step 1, dissolving 2.55g of gold fulminate in 50g of water, and fully stirring and dispersing to obtain a clear gold fulminate solution;
step 2, transferring the obtained clear solution into a reaction kettle, setting the temperature of an oven to be 150 ℃, and preserving heat for 6 hours;
and 3, after the reaction is finished, the reaction solution is still a clear and transparent solution, and no solid is generated.
Comparative example 2
The method of preparing gold nanoparticles of this comparative example includes the steps of:
step 1, dissolving 3.5g of gold fulminate in 50g of water, and fully stirring and dispersing to obtain a clear gold fulminate solution;
step 2, transferring the obtained clear solution into a reaction kettle, setting the temperature of an oven to be 120 ℃, and preserving heat for 4 hours;
and 3, after the reaction is finished, the reaction solution is still a clear and transparent solution, and no solid is generated.
The preferred embodiments of the present invention have been described in detail, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.
It should be noted that the various features described in the foregoing embodiments may be combined in any suitable manner without contradiction. The invention is not described in detail in order to avoid unnecessary repetition. In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.
Claims (10)
1. A method of making a gold-containing nanoparticle dispersion, comprising:
preparing a gold ion solution containing an alcohol solvent;
and heating the gold ion solution containing the alcoholic solvent to obtain the gold-containing nanoparticle dispersion.
2. A method of making gold nanoparticles, comprising:
preparing a gold ion solution containing an alcohol solvent;
heating the gold ion solution containing the alcoholic solvent to obtain a gold nanoparticle-containing dispersion;
and separating the gold-containing nanoparticle dispersion to obtain gold nanoparticles.
3. The method according to any one of claims 1 or 2, wherein the alcohol solvent is at least one of ethylene glycol, isopropanol, n-propanol, and tert-butanol.
4. The method according to any one of claims 1 or 2, wherein the step of preparing the alcohol solvent-containing gold ion solution comprises adding one of gold ion raw materials of gold chlorate and gold fulminate into an alcohol solvent for mixing to obtain the alcohol solvent-containing gold ion solution.
5. The method according to claim 4, wherein the mass ratio of the gold ion raw material to the alcohol solvent is 0.02 to 0.5.
6. The method according to claim 4, wherein the gold ion raw material is gold fulminate, the alcohol solvent is isopropanol, and the mass ratio of the gold ion raw material to the alcohol solvent is 0.05-0.3.
7. The method of any one of claims 1 or 2, wherein the step of heating the alcoholic solvent-containing gold ion solution comprises heating the alcoholic solvent-containing gold ion solution to 85-150 ℃.
8. The method according to claim 7, wherein the step of heating the alcoholic solvent-containing gold ion solution further comprises reacting the alcoholic solvent-containing gold ion solution for 1 to 6 hours after heating the alcoholic solvent-containing gold ion solution to 85 to 150 ℃ in the reaction kettle.
9. The method of claim 2, wherein the step of separating the dispersion of gold-containing nanoparticles comprises separating the gold nanoparticles from the dispersion of gold-containing nanoparticles by at least one of filtration, sedimentation, or centrifugation.
10. A gold nanoparticle produced by the method for producing a gold nanoparticle according to any one of claims 2 to 9.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4539041A (en) * | 1982-12-21 | 1985-09-03 | Universite Paris Vii | Process for the reduction of metallic compounds by polyols, and metallic powders obtained by this process |
| US20040025635A1 (en) * | 2001-04-02 | 2004-02-12 | Kurihara Lynn K. | Processing of nanocrystalline metallic powders and coatings using the polyol process |
| US20060159603A1 (en) * | 2005-01-14 | 2006-07-20 | Cabot Corporation | Separation of metal nanoparticles |
| JP2007239053A (en) * | 2006-03-09 | 2007-09-20 | Kyushu Univ | Method for producing alloy nanoparticle and hydrogen storage alloy |
| CN102371356A (en) * | 2010-08-23 | 2012-03-14 | 清华大学 | Preparation method of gold nanoparticles |
| CN103418800A (en) * | 2013-07-19 | 2013-12-04 | 长沙铂鲨环保设备有限公司 | Method for preparing nanogold |
-
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- 2022-03-31 CN CN202210335727.XA patent/CN114682791A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4539041A (en) * | 1982-12-21 | 1985-09-03 | Universite Paris Vii | Process for the reduction of metallic compounds by polyols, and metallic powders obtained by this process |
| US20040025635A1 (en) * | 2001-04-02 | 2004-02-12 | Kurihara Lynn K. | Processing of nanocrystalline metallic powders and coatings using the polyol process |
| US20060159603A1 (en) * | 2005-01-14 | 2006-07-20 | Cabot Corporation | Separation of metal nanoparticles |
| JP2007239053A (en) * | 2006-03-09 | 2007-09-20 | Kyushu Univ | Method for producing alloy nanoparticle and hydrogen storage alloy |
| CN102371356A (en) * | 2010-08-23 | 2012-03-14 | 清华大学 | Preparation method of gold nanoparticles |
| CN103418800A (en) * | 2013-07-19 | 2013-12-04 | 长沙铂鲨环保设备有限公司 | Method for preparing nanogold |
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