CN112846218A - Preparation method of gold-platinum-silver material with asymmetric structure - Google Patents
Preparation method of gold-platinum-silver material with asymmetric structure Download PDFInfo
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- 239000000463 material Substances 0.000 title claims abstract description 51
- GDYSGADCPFFZJM-UHFFFAOYSA-N [Ag].[Pt].[Au] Chemical compound [Ag].[Pt].[Au] GDYSGADCPFFZJM-UHFFFAOYSA-N 0.000 title claims abstract description 47
- 238000002360 preparation method Methods 0.000 title claims abstract description 6
- SQGYOTSLMSWVJD-UHFFFAOYSA-N silver(1+) nitrate Chemical compound [Ag+].[O-]N(=O)=O SQGYOTSLMSWVJD-UHFFFAOYSA-N 0.000 claims abstract description 62
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims abstract description 51
- CIWBSHSKHKDKBQ-JLAZNSOCSA-N Ascorbic acid Chemical compound OC[C@H](O)[C@H]1OC(=O)C(O)=C1O CIWBSHSKHKDKBQ-JLAZNSOCSA-N 0.000 claims abstract description 38
- 230000012010 growth Effects 0.000 claims abstract description 37
- JUWSSMXCCAMYGX-UHFFFAOYSA-N gold platinum Chemical group [Pt].[Au] JUWSSMXCCAMYGX-UHFFFAOYSA-N 0.000 claims abstract description 36
- 229910001961 silver nitrate Inorganic materials 0.000 claims abstract description 28
- 239000011668 ascorbic acid Substances 0.000 claims abstract description 19
- 229960005070 ascorbic acid Drugs 0.000 claims abstract description 19
- 235000010323 ascorbic acid Nutrition 0.000 claims abstract description 19
- 238000006243 chemical reaction Methods 0.000 claims abstract description 16
- 238000000034 method Methods 0.000 claims abstract description 14
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 claims abstract description 13
- 239000011591 potassium Substances 0.000 claims abstract description 13
- 229910052700 potassium Inorganic materials 0.000 claims abstract description 13
- 238000002156 mixing Methods 0.000 claims abstract description 11
- 230000035040 seed growth Effects 0.000 claims abstract description 5
- LZZYPRNAOMGNLH-UHFFFAOYSA-M Cetrimonium bromide Chemical compound [Br-].CCCCCCCCCCCCCCCC[N+](C)(C)C LZZYPRNAOMGNLH-UHFFFAOYSA-M 0.000 claims description 81
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 52
- 239000006228 supernatant Substances 0.000 claims description 31
- WOWHHFRSBJGXCM-UHFFFAOYSA-M cetyltrimethylammonium chloride Chemical compound [Cl-].CCCCCCCCCCCCCCCC[N+](C)(C)C WOWHHFRSBJGXCM-UHFFFAOYSA-M 0.000 claims description 19
- 238000003756 stirring Methods 0.000 claims description 19
- 229910052709 silver Inorganic materials 0.000 claims description 17
- 239000004332 silver Substances 0.000 claims description 17
- FFRBMBIXVSCUFS-UHFFFAOYSA-N 2,4-dinitro-1-naphthol Chemical compound C1=CC=C2C(O)=C([N+]([O-])=O)C=C([N+]([O-])=O)C2=C1 FFRBMBIXVSCUFS-UHFFFAOYSA-N 0.000 claims description 16
- 238000010438 heat treatment Methods 0.000 claims description 16
- 239000000203 mixture Substances 0.000 claims description 16
- 238000005119 centrifugation Methods 0.000 claims description 13
- 230000005540 biological transmission Effects 0.000 claims description 12
- 239000000047 product Substances 0.000 claims description 12
- 229910004042 HAuCl4 Inorganic materials 0.000 claims description 8
- 239000008367 deionised water Substances 0.000 claims description 8
- 229910021641 deionized water Inorganic materials 0.000 claims description 8
- 238000004090 dissolution Methods 0.000 claims description 8
- 239000012467 final product Substances 0.000 claims description 8
- 239000005457 ice water Substances 0.000 claims description 8
- 239000007788 liquid Substances 0.000 claims description 7
- 238000003760 magnetic stirring Methods 0.000 claims description 7
- 239000012279 sodium borohydride Substances 0.000 claims description 7
- 229910000033 sodium borohydride Inorganic materials 0.000 claims description 7
- 101710134784 Agnoprotein Proteins 0.000 claims description 6
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 abstract description 24
- 229910052697 platinum Inorganic materials 0.000 abstract description 12
- 239000004094 surface-active agent Substances 0.000 abstract description 4
- 238000004140 cleaning Methods 0.000 abstract 2
- 238000004627 transmission electron microscopy Methods 0.000 abstract 1
- 239000000243 solution Substances 0.000 description 121
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 16
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- 239000002184 metal Substances 0.000 description 5
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- 150000002739 metals Chemical class 0.000 description 3
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- 238000002198 surface plasmon resonance spectroscopy Methods 0.000 description 2
- 238000001308 synthesis method Methods 0.000 description 2
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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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- 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
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
- B22F1/05—Metallic powder characterised by the size or surface area of the particles
- B22F1/054—Nanosized particles
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y40/00—Manufacture or treatment of nanostructures
Abstract
The invention discloses a preparation method of a gold-platinum-silver material with an asymmetric structure, which mainly comprises the following steps: firstly, growing gold nanorods by using a seed growth method, and then cleaning the successfully grown gold nanorods to obtain gold nanorods with higher purity; then, taking the gold nanorods as seeds, adding a corresponding amount of surfactant and potassium tetrachloroplatinate, uniformly mixing the gold nanorods and the potassium tetrachloroplatinate, and controlling the reaction temperature to enable platinum to successfully grow on two ends of the gold nanorods; and then cleaning the gold-platinum structure to obtain gold-platinum with higher purity, taking the gold-platinum as a new seed, adding corresponding amounts of a surfactant, silver nitrate and an ascorbic acid solution, and controlling the reaction temperature to finally obtain the asymmetrically-grown gold-platinum-silver material. The growth was observed by transmission electron microscopy. The gold-platinum-silver material with the asymmetric structure synthesized by the method grows uniformly. The method has the advantages of simple reaction conditions, high reaction rate and low cost.
Description
Technical Field
The invention relates to the field of synthesis of metal nano materials, in particular to a preparation method of a gold-platinum-silver material with an asymmetric structure.
Background
Research on noble metal nanoparticles has been rapidly developed in recent years, with gold nanorods being the most prominent. Since gold nanorods have very abundant chemical and physical properties, first it can be used in life sciences including in vitro diagnostics, in vivo imaging and in vivo therapy. Secondly, gold nanorods are also widely used in the sensor field, and can be used for micro-molecule and ion detection due to the enhanced surface raman scattering and surface plasmon resonance properties of the gold nanorods. Meanwhile, the gold nanorods can also be made into optical elements, such as: near infrared filters, solar cells, polarizers, and the like. In recent years, the excellent performance of bimetallic structures has become well known and has become the focus of research. Firstly, because silver has excellent surface properties and chemical activity, the silver can show unique thermal, electrical, optical, acoustic, magnetic, mechanical and catalytic properties, and can be widely applied to the fields of superconduction, chemical engineering, medicine, optics, electronics, electrical appliances and the like. Therefore, it is very important to combine the excellent properties of gold and silver. Besides, the gold nanorods also have an important application-being widely applied to the field of catalysis, namely, under the same temperature and chemical and physical environment, the platinum-coated gold nanorods can have higher catalytic activity than a single platinum catalyst with the same dosage, and simultaneously have better stability. The catalytic performance of the catalyst is particularly remarkable for the photothermal conversion characteristic, on one hand, the catalyst can provide temperature activation on the surface of the nano particles, and on the other hand, the catalyst can save energy required by heating the whole solution system. Therefore, how to synthesize the catalyst with the bimetallic structure efficiently becomes the focus of researchers.
Therefore, how to combine the excellent performances of three metals of gold, platinum and silver into a whole can be widely used in the aspects of biological medical treatment, optical catalysis and the like. Therefore, the synthesis of the three metals becomes a key to be explored by researchers, and how to efficiently synthesize the uniform gold-platinum-silver material becomes a problem to be solved at present.
Disclosure of Invention
In order to solve the problems of low synthesis efficiency of the gold-platinum-silver material and uneven final synthesis result, the invention provides the gold-platinum-silver material with the asymmetric structure and the preparation method thereof, which can efficiently synthesize the uniform gold-platinum-silver material with the asymmetric structure, and have simple reaction conditions and low cost.
In order to achieve the purpose of the invention, the invention adopts the following technical scheme:
a synthetic method of a gold-platinum-silver material with an asymmetric structure comprises the following steps:
and step S1, preparing the gold nanorods by using a seed growth method.
Step S2, taking gold nanorods which are cleaned and dispersed in low-concentration Cetyl Trimethyl Ammonium Bromide (CTAB) as new seeds, adding corresponding amounts of CTAB, silver nitrate solution and potassium tetrachloroplatinate solution on the seeds, and controlling the reaction temperature to synthesize the gold-platinum bimetallic structure;
step S3, taking out the gold-platinum which is cleaned and dispersed in low concentration CTAB as new seed, then adding Cetyl Trimethyl Ammonium Chloride (CTAC), heating at 60 deg.C for 20 min; and then controlling the rate of adding silver nitrate and ascorbic acid, and heating for 2 hours to synthesize the gold-platinum-silver material.
Wherein the step S1 further includes the following steps:
s10 mixing 10mL CTAB (0.1M) and 0.25mL HAuCl4(10mM) are mixed in a bottle with an ice-water mixture and a weighed quantity of NaBH4Mix to make 0.01M solution, and add 0.6mL into the bottle and stir vigorously. The solution changed from golden yellow to brown yellow, which is a seed solution.
S11 2.5mL CTAB (0.1M) and 0.037g NaOL were dissolved in 21.25mL of water at 50 ℃. After dissolution, the solution was cooled to 30 ℃ and then 0.9mL of AgNO was added3(4mM) solution. Standing at 30 deg.C for 15 minAfter that, 0.25mL of HAuCl was added4(10 mM). After stirring (400rpm) for 60-90 minutes, the solution turned from golden yellow to colorless. This is the growth solution.
S12 pH was adjusted by adding 0.3mL HCl (37 wt.%) to the growth solution. Then 75. mu.L of AA (64mM), 40. mu.L of the seed solution were added in succession and stirred vigorously. The final solution was left to stand for 12 hours in a 30 ℃ water bath.
S13 the solution after growth was centrifuged (7000rpm,30 minutes), the supernatant removed and CTAB (1-2mM) added, followed by a second centrifugation (7000rpm,30 minutes). After removal of the supernatant, it was dispersed in a corresponding volume of CTAB (1-2 mM).
The step S2 further includes the steps of:
s20, placing 0.5mL of gold nanorods dispersed in CTAB into a bottle, adding 2.2mL of 0.1M CTAB, 17.8mL of deionized water, 0.25mL of silver nitrate solution and 1mL of 2mM potassium tetrachloroplatinate solution, and uniformly mixing. Heating in 80 deg.C water bath for 30 min;
s21: 7000rpm,30 minutes centrifugation of the solution after growth, removal of the supernatant after adding 1-2mM CTAB, two 7000rpm,30 minutes centrifugation; after removing the clear liquid, dispersing the solution in 1-2mM CTAB with a corresponding volume, and observing the growth condition of the gold-platinum by using a transmission electron microscope;
the step S3 further includes the steps of:
s30: the gold-platinum dispersed in CTAB at a low concentration was removed, 17mL of 30mM CTAC was added, mixed well, and heated in a water bath at 60 ℃ for 20 minutes.
S31: to the above solution was added 1mL of a 4mM silver nitrate solution and 1mL of a 100mM ascorbic acid solution prepared with 30mM CTAC, respectively, using a syringe pump. The addition rates of the two solutions were controlled, i.e., 0.5mL/min. The steps are all completed under the condition of water bath at 60 ℃, and then the water bath is heated for 2 hours under the magnetic stirring of 400rpm and then taken out. And 7000rpm of the final product obtained is centrifuged for 30 minutes, 1-2mM CTAB is added after supernatant liquid is removed, 7000rpm is centrifuged for two times for 30 minutes, and a transmission electron microscope sample is prepared, so that the successfully synthesized gold-platinum-silver material with the asymmetric structure can be observed.
As a further improvement, the step S2 is carried out under the water bath heating condition of 80 ℃, the reaction time is greatly shortened, namely 30 minutes is used for obtaining the gold-platinum bimetallic structure, and meanwhile, the step S3 uses a syringe pump to simultaneously control the dropping rate of silver nitrate and ascorbic acid, so as to obtain the gold-platinum-silver material with the asymmetric structure.
In the technical scheme of the invention, the synthesis is carried out by adopting a seed growth method, and the whole process can be divided into two parts. In the first part, a seed growing method is firstly utilized to successfully synthesize uniform gold nanorods. And secondly, taking the cleaned gold nanorods as seeds, adding a surfactant CTAB, a silver nitrate solution and a potassium tetrachloroplatinate solution, and heating for half an hour in a water bath at the temperature of 80 ℃ to finally obtain a gold-platinum bimetallic structure with more deposits at two ends of the gold nanorods and basically no deposits at the side surfaces. The reason why the reaction is heated in a water bath at 80 ℃ is that the growth rate can be greatly increased; and the third part, a silver nitrate solution and an ascorbic acid solution are simultaneously added dropwise by using a syringe pump, because the reaction rate can be controlled, so that the uniformity of the final asymmetric gold-platinum-silver structure is controlled, and silver is deposited on the side surface of the gold-platinum, and two ends are not substantially deposited. Therefore, the method can be used for efficiently synthesizing the gold-platinum-silver material with the asymmetric structure. And the reaction condition is simple and the cost is low.
The invention synthesizes a gold-platinum-silver material with an asymmetric structure, the material takes a gold nanorod as a core, platinum is deposited at two ends of the gold nanorod, and then silver is taken as a shell, and the silver uniformly grows on the side surface of the gold nanorod. The final synthesized gold-platinum-silver material has an asymmetric structure.
As a further improvement, the material is prepared by the material of claim 1, wherein the gold nanorods which have successfully grown are used as seeds, platinum grows at two ends of the gold nanorods by adding a potassium tetrachloroplatinate solution, and silver nitrate and ascorbic acid are added dropwise by using a syringe pump to control the growth of silver on the side surfaces of the gold-platinum bimetal; the previous reaction rate is changed to control the uniform growth of silver. Finally, the gold-platinum-silver material with an asymmetric structure is formed.
The invention synthesizes the gold-platinum-silver material with an asymmetric structure, and has the following beneficial effects:
(1) the synthesized gold-platinum-silver material with the asymmetric structure does not completely change the performance of the gold nanorods, but retains the specific properties of the gold nanorods.
(2) The uniform growth of the gold-platinum-silver material enhances the catalytic performance of the gold nanorods, and the gold-platinum-silver nanorod has three metal structures of gold, platinum and silver, so that the catalytic activity can be enhanced, and the effect of lower energy is realized.
(3) The synthesis method of the gold-platinum-silver material is simple, and the finally obtained product gold-platinum-silver is very stable and has extremely strong reliability.
(4) Gold-platinum-silver materials have some of the special advantageous properties of gold, platinum and silver, and thus may have wider applications. For example: biomedicine, optical catalysis, etc.
Drawings
FIG. 1 is a flow chart of the steps of the synthesis of gold-platinum-silver material of the present invention;
FIG. 2 is a transmission electron micrograph of gold nanorods synthesized according to instantiation 1 of the present invention;
FIG. 3 is a transmission electron micrograph of a gold-platinum bimetal synthesized in example 1 of the present invention;
fig. 4 is a transmission electron micrograph of the gold-platinum-silver material of example 1 of the present invention.
Detailed Description
The technical solution provided by the present invention will be further explained with reference to the accompanying drawings.
The gold nanorods have good physical and chemical properties, surface plasmon resonance performance and can be widely applied to the field of catalysis, especially photo-thermal conversion. Therefore, the prepared gold nanorods are used as seeds, and then the surfactant, a small amount of silver nitrate solution and potassium tetrachloroplatinate solution are added to enable platinum to grow at two ends of the gold nanorods, so that the gold-platinum bimetallic material with a special structure is formed. And then the rate of adding silver nitrate and ascorbic acid is controlled by an injection pump by utilizing the gold-platinum material, so that silver is mainly deposited on the side surface of the gold-platinum, and thus, the finally synthesized asymmetric gold-platinum-silver material can greatly enhance the catalytic efficiency, has higher catalytic activity and has higher stability. Therefore, the invention provides a synthetic method of the gold-platinum-silver material with the asymmetric structure.
Referring to fig. 1, the synthesis method of the asymmetric structure gold-platinum-silver material provided by the invention specifically comprises the following steps:
step S1, gold nanorods were prepared using a seed growth method (see fig. 2).
Step S2, taking gold nanorods which are cleaned and dispersed in low-concentration CTAB as new seeds, adding corresponding amounts of CTAB, silver nitrate solution and potassium tetrachloroplatinate solution on the seeds, and controlling the reaction temperature to synthesize a gold-platinum bimetallic structure;
step S3, taking out the gold-platinum which is cleaned and dispersed in low concentration CTAB as a new seed, then adding CTAC, heating at 60 ℃ for 20 minutes; and then controlling the rate of adding silver nitrate and ascorbic acid, and heating for two hours to synthesize the gold-platinum-silver material.
Wherein the step S1 further includes the following steps:
s10 mixing 10mL CTAB (0.1M) and 0.25mL HAuCl4(10mM) are mixed in a bottle with an ice-water mixture and a weighed quantity of NaBH4Mix to make 0.01M solution, and add 0.6mL into the bottle and stir vigorously. The solution changed from golden yellow to brown yellow, which is a seed solution.
S11 2.5mL CTAB (0.1M) and 0.037g NaOL were dissolved in 21.25mL of water at 50 ℃. After dissolution, the solution was cooled to 30 ℃ and then 0.9mL of AgNO was added3(4mM) solution. And left to stand at a constant temperature of 30 ℃ for 15 minutes, after which 0.25mL of HAuCl was added4(10 mM). After stirring (400rpm) for 60-90 minutes, the solution turned from golden yellow to colorless. This is the growth solution.
S12 pH was adjusted by adding 0.3mL HCl (37 wt.%) to the growth solution. Then 75. mu.L of AA (64mM), 40. mu.L of the seed solution were added in succession and stirred vigorously. The final solution was left to stand for 12 hours in a 30 ℃ water bath.
S13 the solution after growth was centrifuged (7000rpm,30 minutes), the supernatant removed and CTAB (1-2mM) added, followed by a second centrifugation (7000rpm,30 minutes). After removal of the supernatant, it was dispersed in a corresponding volume of CTAB (1-2 mM).
The step S2 further includes the steps of:
s20, placing 0.5mL of gold nanorods dispersed in CTAB into a bottle, adding 2.2mL of 0.1M CTAB, 17.8mL of deionized water, 0.25mL of silver nitrate solution and 1mL of 2mM potassium tetrachloroplatinate solution, and uniformly mixing. Heating in 80 deg.C water bath for 30 min;
s21: 7000rpm,30 minutes centrifugation of the solution after growth, removal of the supernatant after adding 1-2mM CTAB, two 7000rpm,30 minutes centrifugation; after removing the clear liquid, dispersing the solution in 1-2mM CTAB with a corresponding volume, and observing the growth condition of the gold-platinum by using a transmission electron microscope;
the step S3 further includes the steps of:
s30: the gold-platinum dispersed in CTAB at a low concentration was removed, 17mL of 30mM CTAC was added, mixed well, and heated in a water bath at 60 ℃ for 20 minutes.
S31: to the above solution was added 1mL of a 4mM silver nitrate solution and 1mL of a 100mM ascorbic acid solution prepared with 30mM CTAC, respectively, using a syringe pump. The addition rates of the two solutions were controlled, i.e., 0.5mL/min. All the steps are completed under the condition of water bath at 60 ℃, and then the water bath is heated for 2 hours under the magnetic stirring of 400rpm and then taken out. And 7000rpm of the final product obtained is centrifuged for 30 minutes, 1-2mM CTAB is added after supernatant liquid is removed, 7000rpm is centrifuged for two times for 30 minutes, and a transmission electron microscope sample is prepared, so that the successfully synthesized gold-platinum-silver material with the asymmetric structure can be observed.
According to the method, the gold nanorods which have successfully grown are used as seeds, platinum grows at two ends of the gold nanorods by adding a potassium tetrachloroplatinate solution, and silver nitrate and ascorbic acid are dropwise added by using an injection pump to control the growth condition of silver on the side surface of the gold-platinum bimetal; the previous reaction rate is changed to control the uniform growth of silver. Finally, the gold-platinum-silver material with an asymmetric structure is formed. Referring to fig. 3, it is a transmission electron microscope image of the gold-platinum bimetallic material prepared by the present invention. The synthesis conditions are that under the temperature of 80 ℃, a small amount of silver nitrate solution which plays a catalytic role and potassium tetrachloroplatinate solution are added to finally enable platinum to grow at two ends of the gold nanorod. As can be seen, the length of the gold-platinum bimetallic material is 89nm, the diameter is 17nm, and the aspect ratio is 5.2. And (3) adding CTAC (cetyl trimethyl ammonium chloride) into the cleaned gold-platinum, controlling the temperature of the gold-platinum in a 60 ℃ water bath, heating the gold-platinum for 20 minutes, controlling the adding rate of silver nitrate and ascorbic acid (prepared by CTAC) by using an injection pump, and heating the gold-platinum in a 60 ℃ water bath for two hours to obtain the structure shown in the figure 4. As can be seen, the length of the Au-Pt-Ag material is 93nm, the diameter is 46nm, and the length-diameter ratio is 2.0. It can also be seen from the figure that the silver in the gold-platinum-silver material with the asymmetric structure grows uniformly on the side surface of the gold-platinum bimetallic structure, and the two ends deposit less, so that the structure greatly enhances the stability and has the excellent performances of three metals of gold, platinum and silver.
Example 1:
10mL CTAB (0.1M) and 0.25mL HAuCl4(10mM) are mixed in a bottle with an ice-water mixture and a weighed quantity of NaBH4Mix to make 0.01M solution, and add 0.6mL into the bottle and stir vigorously. The solution changed from golden yellow to brown yellow, which is a seed solution. 2.5mL CTAB (0.1M) and 0.037g NaOL were dissolved in 21.25mL of water at 50 ℃. After dissolution, the solution was cooled to 30 ℃ and then 0.9mL of AgNO was added3(4mM) solution. And left to stand at a constant temperature of 30 ℃ for 15 minutes, after which 0.25mL of HAuCl was added4(10 mM). After stirring (400rpm) for 60-90 minutes, the solution turned from golden yellow to colorless. This is the growth solution. To the growth solution was added 0.3mL HCl (37 wt.%) to adjust the pH. Then 75. mu.L of AA (64mM), 40. mu.L of the seed solution were added in succession and stirred vigorously. The final solution was left to stand for 12 hours in a 30 ℃ water bath. The solution after growth was centrifuged (7000rpm,30 minutes), the supernatant removed and CTAB (1-2mM) added, and centrifuged a second time (7000rpm,30 minutes). After removal of the supernatant, it was dispersed in a corresponding volume of CTAB (1-2 mM). 0.5mL of gold nanorods dispersed in CTAB were taken out of the flask, and CTAB (2.2mL of 0.1M) and deionized water (17.8mL) were added and magnetically stirred at 800rpm in a water bath at 80 ℃ for 30 min. Taking out the reacted product, and twice separatingHeart (7000rpm,30 min) and finally the supernatant was removed and the product was dispersed in CTAB (1-2 mM). The gold-platinum of higher purity was removed and then a silver nitrate solution (1mL 4mM) and an ascorbic acid solution (1mL 100mM) prepared by 30mM CTAC were added simultaneously using a syringe pump, and stirred for 2 hours with a magnetic stirrer (400rpm) in a water bath at 60 ℃. The final product obtained above was centrifuged (7000rpm,30 minutes), the supernatant removed and CTAB (1-2mM) added, followed by a second centrifugation (7000rpm,30 minutes). The transmission electron microscope sample is prepared, and the successful synthesis of the gold-platinum-silver material with the asymmetric structure can be observed.
Example 2:
10mL CTAB (0.1M) and 0.25mL HAuCl4(10mM) are mixed in a bottle with an ice-water mixture and a weighed quantity of NaBH4Mix to make 0.01M solution, and add 0.6mL into the bottle and stir vigorously. The solution changed from golden yellow to brown yellow, which is a seed solution. 2.5mL CTAB (0.1M) and 0.037g NaOL were dissolved in 21.25mL of water at 50 ℃. After dissolution, the solution was cooled to 30 ℃ and then 0.9mL of AgNO was added3(4mM) solution. And left to stand at a constant temperature of 30 ℃ for 15 minutes, after which 0.25mL of HAuCl was added4(10 mM). After stirring (400rpm) for 60-90 minutes, the solution turned from golden yellow to colorless. This is the growth solution. To the growth solution was added 0.3mL HCl (37 wt.%) to adjust the pH. Then 75. mu.L of AA (64mM), 40. mu.L of the seed solution were added in succession and stirred vigorously. The final solution was left to stand for 12 hours in a 30 ℃ water bath. The solution after growth was centrifuged (7000rpm,30 minutes), the supernatant removed and CTAB (1-2mM) added, and centrifuged a second time (7000rpm,30 minutes). After removal of the supernatant, it was dispersed in a corresponding volume of CTAB (1-2 mM). 1mL of gold nanorods dispersed in CTAB was taken out of a bottle, CTAB (4.4mL of 0.1M) and deionized water (35.6mL) were added, and magnetic stirring was performed at 800rpm in a water bath at 80 ℃ for 30 min. The reacted product was removed, centrifuged twice (7000rpm,30 minutes), and the supernatant was finally removed to disperse the product in CTAB (1-2 mM). The gold-platinum of higher purity was removed and then a silver nitrate solution (2mL 4mM) and an ascorbic acid solution (2mL 100mM) prepared by 30mM CTAC were added simultaneously using a syringe pump, and stirred for 2 hours with a magnetic stirrer (400rpm) in a water bath at 60 ℃. The final product obtained above was centrifuged (7000rpm,30 minutes) to removeCTAB (1-2mM) was added to the supernatant and centrifuged twice (7000rpm,30 minutes). The transmission electron microscope sample is prepared, and the successful synthesis of the gold-platinum-silver material with the asymmetric structure can be observed.
Example 3:
10mL CTAB (0.1M) and 0.25mL HAuCl4(10mM) are mixed in a bottle with an ice-water mixture and a weighed quantity of NaBH4Mix to make 0.01M solution, and add 0.6mL into the bottle and stir vigorously. The solution changed from golden yellow to brown yellow, which is a seed solution. 2.5mL CTAB (0.1M) and 0.037g NaOL were dissolved in 21.25mL of water at 50 ℃. After dissolution, the solution was cooled to 30 ℃ and then 0.9mL of AgNO was added3(4mM) solution. And left to stand at a constant temperature of 30 ℃ for 15 minutes, after which 0.25mL of HAuCl was added4(10 mM). After stirring (400rpm) for 60-90 minutes, the solution turned from golden yellow to colorless. This is the growth solution. To the growth solution was added 0.3mL HCl (37 wt.%) to adjust the pH. Then 75. mu.L of AA (64mM), 40. mu.L of the seed solution were added in succession and stirred vigorously. The final solution was left to stand for 12 hours in a 30 ℃ water bath. The solution after growth was centrifuged (7000rpm,30 minutes), the supernatant removed and CTAB (1-2mM) added, and centrifuged a second time (7000rpm,30 minutes). After removal of the supernatant, it was dispersed in a corresponding volume of CTAB (1-2 mM). 0.25mL of gold nanorods dispersed in CTAB was taken out of the flask, CTAB (1.1mL of 0.1M) and deionized water (8.9mL) were added, and magnetic stirring was carried out at 800rpm in a water bath at 80 ℃ for 30 min. The reacted product was removed, centrifuged twice (7000rpm,30 minutes), and the supernatant was finally removed to disperse the product in CTAB (1-2 mM). The gold-platinum of higher purity was removed and then a silver nitrate solution (0.5mL 4mM) and an ascorbic acid solution (0.5mL 100mM) prepared by 30mM CTAC were added simultaneously by a syringe pump, followed by stirring with a magnetic stirrer (400rpm) for 2 hours in a water bath at 60 ℃. The final product obtained above was centrifuged (7000rpm,30 minutes), the supernatant removed and CTAB (1-2mM) added, followed by a second centrifugation (7000rpm,30 minutes). The transmission electron microscope sample is prepared, and the successful synthesis of the gold-platinum-silver material with the asymmetric structure can be observed.
Example 4:
10mL CTAB (0.1M) and 0.25mL HAuCl4(10mM) mixed in a bottle with iceWater mixture and weighed NaBH of a certain mass4Mix to make 0.01M solution, and add 0.6mL into the bottle and stir vigorously. The solution changed from golden yellow to brown yellow, which is a seed solution. 2.5mL CTAB (0.1M) and 0.037g NaOL were dissolved in 21.25mL of water at 50 ℃. After dissolution the solution was cooled to 30 ℃ after which 0.9mL of AgNO3(4mM) solution was added. And left to stand at a constant temperature of 30 ℃ for 15 minutes, after which 0.25mL of HAuCl was added4(10 mM). After stirring (400rpm) for 60-90 minutes, the solution turned from golden yellow to colorless. This is the growth solution. To the growth solution was added 0.3mL HCl (37 wt.%) to adjust the pH. Then 75. mu.L of AA (64mM), 40. mu.L of the seed solution were added in succession and stirred vigorously. The final solution was left to stand for 12 hours in a 30 ℃ water bath. The solution after growth was centrifuged (7000rpm,30 minutes), the supernatant removed and CTAB (1-2mM) added, and centrifuged a second time (7000rpm,30 minutes). After removal of the supernatant, it was dispersed in a corresponding volume of CTAB (1-2 mM). 0.45mL of gold nanorods dispersed in CTAB was taken out of the flask, CTAB (1.98mL of 0.1M) and deionized water (16.02mL) were added, and magnetic stirring was carried out at 800rpm in a water bath at 80 ℃ for 30 min. The reacted product was removed, centrifuged twice (7000rpm,30 minutes), and the supernatant was finally removed to disperse the product in CTAB (1-2 mM). The gold-platinum of higher purity was removed and then a silver nitrate solution (0.9mL 4mM) and an ascorbic acid solution (0.9mL 100mM) prepared by 30mM CTAC were added simultaneously by a syringe pump, followed by stirring with a magnetic stirrer (400rpm) for 2 hours in a water bath at 60 ℃. The final product obtained above was centrifuged (7000rpm,30 minutes), the supernatant removed and CTAB (1-2mM) added, followed by a second centrifugation (7000rpm,30 minutes). The transmission electron microscope sample is prepared, and the successful synthesis of the gold-platinum-silver material with the asymmetric structure can be observed.
Example 5:
10mL CTAB (0.1M) and 0.25mL HAuCl4(10mM) are mixed in a bottle with an ice-water mixture and a weighed quantity of NaBH4Mix to make 0.01M solution, and add 0.6mL into the bottle and stir vigorously. The solution changed from golden yellow to brown yellow, which is a seed solution. 2.5mL CTAB (0.1M) and 0.037g NaOL were dissolved in 21.25mL of water at 50 ℃. After dissolution the solution was cooled to 30 ℃ after which 0.9mL of AgNO3(4mM) solution was added. Standing at constant temperature of 30 deg.C15 min, after which 0.25mL HAuCl was added4(10 mM). After stirring (400rpm) for 60-90 minutes, the solution turned from golden yellow to colorless. This is the growth solution. To the growth solution was added 0.3mL HCl (37 wt.%) to adjust the pH. Then 75. mu.L of AA (64mM), 40. mu.L of the seed solution were added in succession and stirred vigorously. The final solution was left to stand for 12 hours in a 30 ℃ water bath. The solution after growth was centrifuged (7000rpm,30 minutes), the supernatant removed and CTAB (1-2mM) added, and centrifuged a second time (7000rpm,30 minutes). After removal of the supernatant, it was dispersed in a corresponding volume of CTAB (1-2 mM). 0.4mL of gold nanorods dispersed in CTAB were taken out of the flask, CTAB (1.76mL of 0.1M) and deionized water (14.24mL) were added, and magnetic stirring was performed at 800rpm in a water bath at 80 ℃ for 30 min. The reacted product was removed, centrifuged twice (7000rpm,30 minutes), and the supernatant was finally removed to disperse the product in CTAB (1-2 mM). The gold-platinum of higher purity was removed and then a silver nitrate solution (0.8mL 4mM) and an ascorbic acid solution (0.8mL 100mM) prepared by 30mM CTAC were added simultaneously by a syringe pump, followed by stirring with a magnetic stirrer (400rpm) for 2 hours in a water bath at 60 ℃. The final product obtained above was centrifuged (7000rpm,30 minutes), the supernatant removed and CTAB (1-2mM) added, followed by a second centrifugation (7000rpm,30 minutes). The transmission electron microscope sample is prepared, and the successful synthesis of the gold-platinum-silver material with the asymmetric structure can be observed.
Finally, it should be noted that the above embodiments are only used to help understand the method of the present invention and its core idea, and not to limit it. Those of ordinary skill in the art will understand that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications or substitutions do not depart from the spirit and scope of the present invention's device solution. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (3)
1. A preparation method of a gold-platinum-silver material with an asymmetric structure is characterized by comprising the following steps:
step S1, preparing gold nanorods by using a seed growth method;
step S2, taking gold nanorods which are cleaned and dispersed in low-concentration Cetyl Trimethyl Ammonium Bromide (CTAB) as new seeds, adding corresponding amounts of CTAB, silver nitrate solution and potassium tetrachloroplatinate solution on the seeds, and controlling the reaction temperature to synthesize the gold-platinum bimetallic structure;
step S3, taking out the gold-platinum which is cleaned and dispersed in low concentration CTAB as new seed, then adding Cetyl Trimethyl Ammonium Chloride (CTAC), heating at 60 deg.C for 20 min; then controlling the rate of adding silver nitrate and ascorbic acid, and heating for 2 hours to synthesize a gold-platinum-silver material;
wherein the step S1 further includes the following steps:
s10 mixing 10mL of 0.1M CTAB with 0.25mL of 10mM HAuCl4Mixing in a bottle, mixing with ice-water mixture and certain weighed NaBH4Mixing to prepare 0.01M solution, and adding 0.6mL of the solution into a bottle for vigorous stirring; the solution turns from golden yellow to brown yellow, which is a seed solution;
s11 dissolving 2.5mL of 0.1M CTAB and 0.037g of NaOL in 21.25mL of water at 50 ℃; after dissolution, the solution was cooled to 30 ℃ and 0.9mL of 4mM AgNO was added3A solution; and left to stand at a constant temperature of 30 ℃ for 15 minutes, after which 0.25mL of 10mM HAuCl was added4(ii) a After stirring at 400rpm for 60-90 minutes, the solution turns from golden yellow to colorless; this is the growth solution;
s12, adding 0.3mL of 37 wt.% HCl into the growth solution to regulate the pH value; then 75 μ L of 64mM AA, 40 μ L of seed solution are added in turn and stirred vigorously; standing the final solution for 12 hours in a water bath at 30 ℃;
s13, 7000rpm of the solution after growth is centrifuged for 30 minutes, 1-2mM CTAB is added after supernatant liquid is removed, 7000rpm is carried out twice, and centrifugation is carried out for 30 minutes; after removing the clear solution, dispersing in a corresponding volume of 1-2mM CTAB;
the step S2 further includes the steps of:
s20, putting 0.5mL of gold nanorods dispersed in CTAB into a bottle, adding 2.2mL of 0.1M CTAB, 17.8mL of deionized water, 0.25mL of silver nitrate solution and 1mL of 2mM potassium tetrachloroplatinate solution, and uniformly mixing; heating in 80 deg.C water bath for 30 min;
s21: 7000rpm,30 minutes centrifugation of the solution after growth, removal of the supernatant after adding 1-2mM CTAB, two 7000rpm,30 minutes centrifugation; after removing the clear liquid, dispersing the solution in 1-2mM CTAB with a corresponding volume, and observing the growth condition of the gold-platinum by using a transmission electron microscope;
the step S3 further includes the steps of:
s30: taking out the gold-platinum dispersed in low-concentration CTAB, adding 17mL of 30mM CTAC, uniformly mixing, and heating in a water bath at 60 ℃ for 20 minutes;
s31: 1mL of a 4mM silver nitrate solution and 1mL of a 100mM ascorbic acid solution prepared with 30mM CTAC were added to the above solution by a syringe pump, respectively; the adding rate of the two solutions is controlled, namely 0.5mL/min, and the two solutions are simultaneously dripped into the product; the steps are all completed under the condition of water bath at 60 ℃, and then the mixture is taken out after being heated for 2 hours in the water bath under the magnetic stirring of 400 rpm; and 7000rpm of the final product obtained is centrifuged for 30 minutes, 1-2mM CTAB is added after supernatant liquid is removed, 7000rpm is centrifuged for two times for 30 minutes, and a transmission electron microscope sample is prepared, so that the successfully synthesized gold-platinum-silver material with the asymmetric structure can be observed.
2. The method for preparing an asymmetrically-structured gold-platinum-silver material according to claim 1, wherein the step S2 is performed under the water bath heating condition of 80 ℃, the reaction rate is increased, and the step S3 controls the dropping rate of the silver nitrate solution and the ascorbic acid solution by using a syringe pump, so that silver can uniformly grow on the surface of the gold nanorods; so that the finally synthesized asymmetric gold-platinum-silver structure has high uniformity.
3. The method for preparing an asymmetrically structured gold-platinum-silver material according to claim 1, wherein the prepared gold-platinum-silver material has a length of 93nm and a diameter of 46 nm.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113369494A (en) * | 2021-06-11 | 2021-09-10 | 杭州电子科技大学 | Hollow gold-silver-platinum trimetal material and synthesis method thereof |
| CN113385687A (en) * | 2021-06-11 | 2021-09-14 | 杭州电子科技大学 | Asymmetric gold-silver-platinum-silver multilayer composite material and synthetic method thereof |
| CN115383106A (en) * | 2022-08-01 | 2022-11-25 | 中国科学院合肥物质科学研究院 | Asymmetric gold-silver nano-structure material and preparation method and application thereof |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113369494A (en) * | 2021-06-11 | 2021-09-10 | 杭州电子科技大学 | Hollow gold-silver-platinum trimetal material and synthesis method thereof |
| CN113385687A (en) * | 2021-06-11 | 2021-09-14 | 杭州电子科技大学 | Asymmetric gold-silver-platinum-silver multilayer composite material and synthetic method thereof |
| CN113369494B (en) * | 2021-06-11 | 2023-06-06 | 杭州电子科技大学 | Hollow gold-silver-platinum trimetallic material and synthesis method thereof |
| CN115383106A (en) * | 2022-08-01 | 2022-11-25 | 中国科学院合肥物质科学研究院 | Asymmetric gold-silver nano-structure material and preparation method and application thereof |
| CN115383106B (en) * | 2022-08-01 | 2023-12-19 | 中国科学院合肥物质科学研究院 | Asymmetric gold-silver nano-structure material and preparation method and application thereof |
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