CN102974837A - Preparation method for flaky nanometer silver powder - Google Patents

Preparation method for flaky nanometer silver powder Download PDF

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Publication number
CN102974837A
CN102974837A CN2012105009111A CN201210500911A CN102974837A CN 102974837 A CN102974837 A CN 102974837A CN 2012105009111 A CN2012105009111 A CN 2012105009111A CN 201210500911 A CN201210500911 A CN 201210500911A CN 102974837 A CN102974837 A CN 102974837A
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silver
salt
preparation
silver powder
ferrous
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CN102974837B (en
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李中春
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Jiangsu University of Technology
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Jiangsu University of Technology
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Priority to CN201510815965.0A priority patent/CN105268993B/en
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Abstract

The invention discloses a preparation method for flaky nanometer silver powder. The flaky nanometer silver powder is prepared by performing reaction on a surfactant-containing aqueous solution of silver salt and a solution of ferrous salt at temperature of 0 to 100 DEG C, wherein the silver salt is silver nitrate, silver sulfate or silver acetate; a surfactant is polyvinylpyrrolidone, hexadecyl trimethyl ammonium bromide, sodium dodecyl sulfate or polyethylene glycol; the ferrous salt is ammonium ferrous sulfate or ferrous sulfate; the weight ratio of the silver salt to the ferrous salt is 2:1 to 1:4; and the weight ratio of the silver salt to the surfactant is 50:1 to 1:2. The flaky nanometer silver powder finally obtained by the method has an undiversified shape and high purity. The method also has the advantages of short reaction time, high efficiency, mild reaction conditions, simple process and equipment, low production cost, convenience for operation, no pollution and the like, and is particularly suitable for industrial production.

Description

The preparation method of flake nano silver powder
Technical field
The present invention relates to a kind of preparation method of metal dust, be specifically related to a kind of preparation method of flake nano silver powder.
Background technology
Flake nano silver powder is face contact or line contact between particle because its surface area is relatively large, so resistance is relatively low, electric conductivity is better.In addition, the surface plasma resonance performance that flake nano silver powder is special shows and spheroidal particle and the distinct optical property of body phase material it.Therefore, flake nano silver powder has great using value in fields such as microelectronics, catalysis, surface-enhanced Raman, metal-enhanced fluorescence, infrared therapeutic, biomarker, nano conductive adhesive, electronic package materials.
The preparation method of flake nano silver powder mainly contains reduction ball-milling method, solution reduction, photo-induction inducing defecation by enema and suppository, thermal transition method, crystal seed method, template, solvent-thermal method, microwave irradiation and ultrasonic auxiliary law etc.Wherein solution reduction be at present commonly used also be one of the preparation method of tool potentiality.
Chinese patent literature CN1935422A discloses a kind of preparation method of single dispersion triangular nano silver slice, and the method is that the silver nitrate alcoholic solution is mixed in the ternary solution system that is comprised of water, PVP and n-amyl alcohol, obtains triangular nano silver slice through heat treatment.
Chinese patent literature 1958197A discloses a kind of preparation method of Nano silver piece, the method is first silver-colored source to be obtained the Nano silver grain seed with the sodium borohydride reaction in the presence of coating agent, and then with this seed and Yin Yuan, coating agent and weak reductant reaction preparation Nano silver piece, wherein weak reductant is hydrazine hydrate, ascorbic acid, HAS, HAN.
Chinese patent literature 101947655A discloses a kind of preparation method of triangular silver nanosheet, the method is that oxyacid silver is mixed with trisodium citrate and polyvinylpyrrolidone first, then add sodium borohydride and carry out reduction reaction, add again the hydrogen peroxide reaction, obtain triangular silver nanosheet.
Chinese patent literature CN102632246A discloses a kind of a large amount of method for preparing the series Nano silver piece, the method is that high molecular surfactant, halogen-containing slaine and cupric inorganic salts assistant are mixed to get solution A, in the mixed solvent of metal silver salt adding by polyalcohol and dimethyl formamide component, obtain solution B, solution A and solution B are mixed and heated to back flow reaction obtain Nano silver piece.
Above-mentioned various some course of reaction of method for preparing flake nano silver is loaded down with trivial details, and is higher for equipment requirement; Some operation is complicated, and reaction condition is higher, and the reaction time is longer; Some also uses the reagent of contaminated environment; Most importantly the flake nano aluminium powder that obtains of these methods is easy to reunite and grow up, and pattern is not single.
Summary of the invention
The object of the invention is to for the deficiencies in the prior art, provide a kind of product purity height and pattern is single, Processes and apparatus is simple, reaction condition is gentle and the time the is short method for preparing flake nano silver powder.
The technical scheme that realizes the object of the invention is: a kind of preparation method of flake nano silver powder, reacted under 0~100 ℃ temperature by the silver salt solution that contains surfactant and ferrous salt solution and to obtain.
Described silver salt is silver nitrate, silver sulfate or silver acetate.
Described surfactant is polyvinylpyrrolidone (PVP), softex kw (CTAB), lauryl sodium sulfate (SDS) or polyethylene glycol (PEG).
Described ferrous salt is iron ammonium sulfate (also can be described as six ferrous sulfate hydrate ammoniums) or ferrous sulfate (also can be described as green vitriol).
Preferred 40 ℃~80 ℃ of above-mentioned reaction temperature.
The weight ratio of described silver salt and described ferrous salt is 2: 1~1: 4, preferred 1: 1~1: 2.
The weight ratio of described silver salt and described surfactant is 50: 1~1: 2, preferred 10: 1~5: 1.
The good effect that the present invention has: (1) method of the present invention does not adopt the reducing agent of the common reduction silver salt such as sodium borohydride, hydrazine hydrate, but adopts ferrous salt reduction soluble silver salt, and the flake nano silver powder pattern that finally obtains is single, and purity is high.(2) method reaction time weak point of the present invention, efficient is high, and reaction condition is gentle.(3) method Processes and apparatus of the present invention is simple, and production cost is low, and easy and simple to handle, and green non-pollution is particularly suitable for large-scale industrialization production.
Description of drawings
Fig. 1 is SEM (SEM) figure of the flake nano silver powder that makes of embodiment 1.
The specific embodiment
(embodiment 1)
The preparation method of the flake nano silver powder of present embodiment is as follows:
1. the silver nitrate of 0.20g and the PVP-K30 of 0.04g are joined in the distilled water of 15mL, abundant stirring and dissolving obtains containing the liquor argenti nitratis ophthalmicus of PVP-K30.
2. six ferrous sulfate hydrate ammoniums with 0.40g join in the distilled water of 15mL, and fully stirring and dissolving obtains l ferrous ammonium sulfate solution.
3. the l ferrous ammonium sulfate solution that 2. step is obtained slowly is added drop-wise in the liquor argenti nitratis ophthalmicus that contains PVP-K30 that 1. step obtain, and is warming up to 60 ℃, insulation reaction 30min.
4. after reaction finishes, leave standstill 1h, then product is carried out centrifugation, with absolute ethyl alcohol and distilled water solid product is washed three times successively, place at last vacuum drying chamber vacuum drying under 80 ℃ temperature, namely get flake nano silver powder.
The SEM figure of the flake nano silver powder that present embodiment makes sees Fig. 1, and as seen from Figure 1, it is high that present embodiment makes flake nano silver powder purity, and pattern is single.
(embodiment 2~embodiment 5)
The preparation method of each embodiment is substantially the same manner as Example 1, and difference sees Table 1.
Table 1
? Embodiment 1 Embodiment 2 Embodiment 3 Embodiment 4 Embodiment 5
Silver salt Silver nitrate Silver nitrate Silver nitrate Silver sulfate Silver acetate
Surfactant PVP-K30 PEG-10000 SDS PVP-K30 CTAB
Ferrous salt Six ferrous sulfate hydrate ammoniums Green vitriol Six ferrous sulfate hydrate ammoniums Green vitriol Six ferrous sulfate hydrate ammoniums
(embodiment 6~embodiment 9)
The preparation method of each embodiment is substantially the same manner as Example 1, and difference sees Table 2.
Table 2
? Embodiment 1 Embodiment 6 Embodiment 7 Embodiment 8 Embodiment 9 Embodiment 10 Embodiment 11
Silver nitrate 0.20g 0.20g 0.20g 0.20g 2.00g 2.00g 2.00g
PVP-K30 0.04g 0.01g 0.02g 0.40g 0.10g 0.04g 0.40g
Six ferrous sulfate hydrate ammoniums 0.40g 0.80g 0.20g 0.10g 2.00g 4.00g 7.00g
Reaction temperature 60℃ 40℃ 20℃ 50℃ 80℃ 0℃ 60℃
Reaction time 30min 28min 35min 30min 32min 25min 30min

Claims (9)

1. the preparation method of a flake nano silver powder is characterized in that: reacted under 0~100 ℃ temperature by the silver salt solution that contains surfactant and ferrous salt solution and obtain.
2. the preparation method of flake nano silver powder according to claim 1, it is characterized in that: described silver salt is silver nitrate, silver sulfate or silver acetate.
3. the preparation method of flake nano silver powder according to claim 1, it is characterized in that: described surfactant is polyvinylpyrrolidone, softex kw, lauryl sodium sulfate or polyethylene glycol.
4. the preparation method of flake nano silver powder according to claim 1, it is characterized in that: described ferrous salt is iron ammonium sulfate or ferrous sulfate.
5. the preparation method of flake nano silver powder according to claim 1, it is characterized in that: reaction temperature is 40 ℃~80 ℃.
6. according to claim 1 to the preparation method of one of 5 described flake nano silver powder, it is characterized in that: the weight ratio of described silver salt and described ferrous salt is 2: 1~1: 4.
7. the preparation method of flake nano silver powder according to claim 6, it is characterized in that: the weight ratio of described silver salt and described ferrous salt is 1: 1~1: 2.
8. according to claim 1 to the preparation method of one of 5 described flake nano silver powder, it is characterized in that: the weight ratio of described silver salt and described surfactant is 50: 1~1: 2.
9. the preparation method of flake nano silver powder according to claim 8, it is characterized in that: the weight ratio of described silver salt and described surfactant is 10: 1~5: 1.
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CN103521777A (en) * 2013-10-11 2014-01-22 南京邮电大学 Method for preparing two-dimensional silver nanosheets of different shapes
CN104551007A (en) * 2015-01-13 2015-04-29 山东大学 Large-scale preparation method of silver nano-sheets
CN104934097A (en) * 2014-03-17 2015-09-23 常宝公司 A conductive paste composition for a flexible substrate and a method for producing the same
CN105050755A (en) * 2013-06-25 2015-11-11 化研科技株式会社 Flake-like silver powder, conductive paste, and method for producing flake-like silver powder
CN105127448A (en) * 2015-09-25 2015-12-09 合肥工业大学 Room-temperature preparation method for nano silver sheet with ultra-large area
CN106623963A (en) * 2016-09-12 2017-05-10 贵研铂业股份有限公司 Flaky ultra-fine and spherical mixing silver powder with adjustable proportion and preparation method thereof
CN108655414A (en) * 2018-06-11 2018-10-16 合肥学院 A kind of quick magnanimity prepares the simple and easy method of two dimension Ag micro Nano materials
CN110449598A (en) * 2019-09-06 2019-11-15 辽宁星空新能源发展有限公司 A kind of method that rapid precipitation prepares two-dimensional metallic silver simple substance nanometer sheet
CN112355321A (en) * 2020-10-09 2021-02-12 肇庆市华师大光电产业研究院 Preparation method of kelp-like silver structure
CN112475310A (en) * 2020-10-16 2021-03-12 湖南诺尔得材料科技有限公司 Preparation method of silver powder with narrow particle size distribution
CN114042929A (en) * 2021-10-26 2022-02-15 西安交通大学 High-concentration silver nano-micron sheet and synthesis method thereof
CN115488347A (en) * 2022-09-09 2022-12-20 淮阴师范学院 Preparation method of multilayer silver nanosheet

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CN111515383B (en) * 2020-04-03 2022-05-27 江苏师范大学 Silver nano triangular protection method based on ferrous ions
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CN105050755A (en) * 2013-06-25 2015-11-11 化研科技株式会社 Flake-like silver powder, conductive paste, and method for producing flake-like silver powder
CN105050755B (en) * 2013-06-25 2017-03-15 化研科技株式会社 The manufacture method of laminar argentum powder, conductive paste and laminar argentum powder
CN103521777A (en) * 2013-10-11 2014-01-22 南京邮电大学 Method for preparing two-dimensional silver nanosheets of different shapes
CN104934097A (en) * 2014-03-17 2015-09-23 常宝公司 A conductive paste composition for a flexible substrate and a method for producing the same
CN104551007A (en) * 2015-01-13 2015-04-29 山东大学 Large-scale preparation method of silver nano-sheets
CN105127448A (en) * 2015-09-25 2015-12-09 合肥工业大学 Room-temperature preparation method for nano silver sheet with ultra-large area
CN106623963A (en) * 2016-09-12 2017-05-10 贵研铂业股份有限公司 Flaky ultra-fine and spherical mixing silver powder with adjustable proportion and preparation method thereof
CN108655414A (en) * 2018-06-11 2018-10-16 合肥学院 A kind of quick magnanimity prepares the simple and easy method of two dimension Ag micro Nano materials
CN110449598A (en) * 2019-09-06 2019-11-15 辽宁星空新能源发展有限公司 A kind of method that rapid precipitation prepares two-dimensional metallic silver simple substance nanometer sheet
CN112355321A (en) * 2020-10-09 2021-02-12 肇庆市华师大光电产业研究院 Preparation method of kelp-like silver structure
CN112475310A (en) * 2020-10-16 2021-03-12 湖南诺尔得材料科技有限公司 Preparation method of silver powder with narrow particle size distribution
CN112475310B (en) * 2020-10-16 2022-12-20 湖南中伟新银材料科技有限公司 Preparation method of silver powder with narrow particle size distribution
CN114042929A (en) * 2021-10-26 2022-02-15 西安交通大学 High-concentration silver nano-micron sheet and synthesis method thereof
CN115488347A (en) * 2022-09-09 2022-12-20 淮阴师范学院 Preparation method of multilayer silver nanosheet
CN115488347B (en) * 2022-09-09 2024-01-26 淮阴师范学院 Preparation method of multilayer silver nano-sheet

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