CN101514407A - Method for preparing nano porous gold - Google Patents
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- CN101514407A CN101514407A CNA2009100197663A CN200910019766A CN101514407A CN 101514407 A CN101514407 A CN 101514407A CN A2009100197663 A CNA2009100197663 A CN A2009100197663A CN 200910019766 A CN200910019766 A CN 200910019766A CN 101514407 A CN101514407 A CN 101514407A
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Abstract
The invention belongs to the field of nano-material preparation, in particular to a method for preparing a nano porous gold. In the invention, the nano porous gold is prepared by combining rapid setting and dealloying. The method comprises the following steps: firstly heating pure aluminium and gold to molten state; secondly; rapidly blowing out alloy liquid with inert gases to cause molten liquid metals to rapidly set on a copper roller which rotates at high speed to prepare alloy ribbons; and finally, carrying out dealloying treatment in acid or alkaline solution. After corrosion process, the nano porous gold is washed till neutrality in distilled water. In the method, the nano porous gold can be obtained by selecting corrosion solution with lower concentration, therefore, the nanoporous gold has simple and convenient operating process and is suitable for large-scale industrial production. In the method, the structure and size of the nanoporous gold can be adjusted according to the ingredients and corrosion solution of master alloy.
Description
Technical field
Invention belongs to field of nano material preparation, relates in particular to a kind of preparation method of nano-porous gold.
Background technology
Nano porous metal is the material with nano-scale hole, and its aperture size is a few nanometer to tens nanometers.Nano porous metal is a kind of special porous material, nano level aperture size makes it have higher specific surface area and other unique physics, chemistry and mechanical property, for example Du Te electromagnetic performance, higher chemical activity, higher intensity etc.Therefore, nano porous metal has huge application potential, and the applied research of carrying out at present mainly contains catalysis, excites, sensing, surface enhanced Raman scattering etc.
At present, taking off alloyage is the main method of preparation nano porous metal, the object of choosing mostly is the binary solid solution alloy, by selecting suitable caustic solution, will be wherein comparatively active dissolving metal, remaining comparatively inert atoms metal is through the final nano-porous structure that forms co-continuous of diffusion reorganization.Calendar year 2001, people (Erlebacher J such as Jonah Erlebacher, AzizM, Karma A, et al.Nature, 2001,410 (22): 450-453.) Ag-32at.%Au and Ag-24at.%Au are taken off after the alloy, made thickness and be about the nanoporous gold thin film that 700nm, aperture size are about 10nm with concentrated nitric acid.2004, people (Ding Y, Kim Y, Erlebacher J.Advanced Materials, 2004,16 (21): 1897-1900.) use 70wt.%HNO such as Ding Yi
3Ag, Au massfraction be 50% the color leaf of commercially available platinum and carried out taking off alloy treatment, made thickness and be about 100nm, aperture size is about the nanoporous gold thin film of 20nm.2005, people (Dursun A such as Dursun Aziz, Pugh D, Corcoran S.Journal of the ElectrochemicalSociety, 2005,152 (2): B65-B72.) with electrolysis corrosive mode Ag-20at.%Au, Ag-25at.%Au and Ag-30at.%Au have been carried out taking off alloy, the electrolytic solution that adopts in the corrosion process is the HClO of 0.1mol/L
42005, the Jing-Fang Huang in China Taiwan and I-Wen Sun (Huang Jing-Fang, Sun I.-Wen.Advanced Functional Materials, 2005,15:989-994.) at first in gold electrode surfaces with the zinc-plated formation of the mode of galvanic deposit Zn-Au alloy, subsequently at ZnCl
2Carry out electrolysis in the-EMIC solion and take off alloy treatment, made nano-porous gold.Adopt the Ag-Au alloy system to prepare nano-porous gold, its cost is than higher; And Zn-Au surface alloying/take off Alloying Treatment prepares the porous gold, its technology more complicated, and also the composition of Zn-Au alloy is difficult to accurately control.
Summary of the invention
The objective of the invention is to overcome above-mentioned the deficiencies in the prior art, the preparation method of the nano-porous gold that a kind of cost is low, technology is simple, nano-porous structure is controlled is provided.
The present invention realizes in the following manner.
A kind of preparation method of nano-porous gold adopts rapid solidification and takes off the method that alloying combines to prepare nano-porous gold, it is characterized in that may further comprise the steps:
1, pure metallic aluminum, gold are heated to molten state, mother alloy liquid is fully mixed;
2, utilize rare gas element that alloy liquid is blown out fast, make fused liquid metal rapid solidification on the copper roller of high speed rotating, prepare alloy strip;
3, in acidity or basic solution, take off Alloying Treatment; Corrosion process is washed till neutrality with nano-porous gold after finishing in distilled water; At last, sample dries and preserves.
The preparation method of above-mentioned nano-porous gold is characterized in that the rare gas element in the step 2 is a kind of of argon gas, nitrogen.Basic solution in the step 3 is sodium hydroxide or potassium hydroxide solution; Acidic solution is a kind of in hydrochloric acid, sulfuric acid, the salpeter solution.Al-Au alloy and 0.1-40wt.% basic solution were room temperature to 90 ℃ reaction 0.1～4 hour in the step 3, and perhaps 0.1～37wt.% hydrochloric acid soln or 0.1-98wt.% sulphuric acid soln or 0.1-70wt.% salpeter solution were room temperature to 90 ℃ reaction 0.1～4 hour.The ratio of greater inequality of step 3 neutral and alkali solution is 20wt.%, and the ratio of greater inequality of acidic solution is 5wt.%.The solidification rate of Al-Au alloy is 10 in the step 3
2～10
6K/s.
Concrete operations are as follows: aforementioned fine aluminium and proof gold metal are joined in the smelting furnace, be heated to molten state, make its alloying through fully stirring.With rare gas element the fused liquid metal is blown out under 0.05-1MPa pressure fast, Quench on the copper roller of high speed rotating makes alloy with 10
2～10
6K/s speed is solidified, and obtaining thickness is 10～200 μ m, and width is 1～50mm, and length is 0.5～50cm alloy strip.Wherein the content of Au is 1～90% (atomic percent), and all the other are Al.Above-mentioned alloy strip joined in acidity or the alkaline corrosion solution take off Alloying Treatment, handled 0.1～4 hour, filter out the solution metal band then, be washed till the pH test paper with distilled water and be neutral, take out at last and place.
Method of the present invention is compared with existing nano-porous gold preparation technology, have following having a few: (1) this method is selected the mother alloy of Al-Au alloy as nano-porous gold for use, the cost of preparation nano-porous gold can be reduced greatly, simultaneously, the speed of response of alloy in etchant solution can be quickened.(2) this method selects for use the lower etchant solution of concentration can obtain nano-porous gold, and operating procedure is easy, suitability for mass industrialized production.(3) this method can be taken off Alloying Treatment in multiple solution such as acidity or alkalescence.(4) present method can be according to the kind of the composition and the etchant solution of mother alloy, the structure and the size of regulation and control nano-porous gold.
Embodiment
Provide six most preferred embodiments of the present invention below:
Embodiment one
(1) according to atomic percent 33.4%Au, all the other are the proportioning of Al, and the Al-Au alloy is put into smelting furnace.Alloy is heated to molten state, makes its alloying through fully stirring.With argon gas fused liquid is blown out under 0.1MPa pressure fast, Quench on the copper roller of high speed rotating, obtaining thickness is the 20-40 micron, and width is the 2-5 millimeter, and length is 1-5 centimetre alloy thin band.
(2) 25 ℃ down with 5% hydrochloric acid soln reaction 0.5 hour, then be heated to 90 ℃ of reactions 0.5 hour to not significantly the reaction bubble produce, stop heating.
(3) reacted product is collected, washed repeatedly to chemical corrosion solution clean fully (wide pH value test paper check flushing distilled water is neutral) with distilled water.Under 25 ℃, dry then and preserve.Aperture, hole wall size are the 60-80 nanometer more, and the pore structure uniform distribution.
Embodiment two
(1) according to atomic percent 20%Au, all the other are the proportioning of Al, and the Al-Au alloy is put into smelting furnace.Alloy is heated to molten state, makes its alloying through fully stirring.With argon gas fused liquid is blown out under 0.1MPa pressure fast, Quench on the copper roller of high speed rotating, obtaining thickness is the 30-50 micron, and width is the 2-5 millimeter, and length is 5-20 centimetre alloy thin band.
(2) 25 ℃ down with 5% hydrochloric acid soln reaction 0.5 hour, then be heated to 90 ℃ of reactions 0.5 hour to not significantly the reaction bubble produce, stop heating.
(3) reacted product is collected, washed repeatedly to chemical corrosion solution clean fully (wide pH value test paper check flushing distilled water is neutral) with distilled water.Under 25 ℃, dry then and preserve.This nano-porous gold has double mode pore distribution.
Embodiment three
Other steps are identical with embodiment two, and argon gas is changed to nitrogen, and 5% hydrochloric acid soln is changed to 5% sulphuric acid soln.This nano-porous gold has double mode pore distribution.
Embodiment four
Other steps are identical with embodiment two, and 5% hydrochloric acid soln is changed to 5% salpeter solution.This nano-porous gold has double mode pore distribution.
Embodiment five
(1) according to atomic percent 40%Au, all the other are the proportioning of Al, and the Al-Au alloy is put into smelting furnace.Alloy is heated to molten state, makes its alloying through fully stirring.With argon gas fused liquid is blown out under 0.1MPa pressure fast, Quench on the copper roller of high speed rotating, obtaining thickness is the 40-60 micron, and width is the 2-6 millimeter, and length is 2-5 centimetre alloy thin band.
(2) in 20% sodium hydroxide solution, be heated to 2 hours extremely not tangible reaction bubbles of 90 ℃ of reactions and produce, stop to heat.
(3) reacted product is collected, washed repeatedly to chemical corrosion solution clean fully (wide pH value test paper check flushing distilled water is neutral) with distilled water.Under 25 ℃, dry then and preserve.This nano-porous gold is the nanoporous metal/composite material with two kinds of nano-porous structures, and the cellular structure mesopore is of a size of the 10-20 nanometer.
Embodiment six
Other steps are identical with embodiment five, and argon gas is changed to nitrogen, and 20% sodium hydroxide solution is changed to 20% potassium hydroxide.The nano-porous gold that obtains is the nanoporous metal/composite material with two kinds of nano-porous structures.
Claims (5)
1, a kind of preparation method of nano-porous gold adopts rapid solidification and takes off the method that alloying combines to prepare nano-porous gold, it is characterized in that may further comprise the steps:
(1) pure metallic aluminum, gold are heated to molten state, mother alloy liquid is fully mixed;
(2) utilize rare gas element that alloy liquid is blown out fast, make fused liquid metal rapid solidification on the copper roller of high speed rotating, prepare alloy strip;
(3) in acidity or basic solution, take off Alloying Treatment; Corrosion process is washed till neutrality with nano-porous gold after finishing in distilled water; At last, sample dries and preserves.
2, the preparation method of nano-porous gold according to claim 1 is characterized in that the rare gas element in the step 2 is a kind of of argon gas, nitrogen; Inert gas pressure is 0.05-1MPa.
3, the preparation method of nano-porous gold according to claim 1 is characterized in that the basic solution in the step 3 is sodium hydroxide or potassium hydroxide solution; Acidic solution is a kind of in hydrochloric acid, sulfuric acid, the salpeter solution.
4, according to the preparation method of claim 1 or 3 described nano-porous golds, it is characterized in that in the step 3 Al-Au alloy and 0.1-40wt.% basic solution room temperature to 90 ℃ reaction 0.1～4 hour, perhaps with 0.1～37wt.% hydrochloric acid soln or with the 0.1-98wt.% sulphuric acid soln or with the 0.1-70wt.% salpeter solution room temperature to 90 ℃ reaction 0.1～4 hour.
5, the preparation method of nano-porous gold according to claim 1 is characterized in that the ratio of greater inequality of step 3 neutral and alkali solution is 20wt.%, and the ratio of greater inequality of acidic solution is 5wt.%; The solidification rate of Al-Au alloy is 10
2～10
6K/s.
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| CN102191399A (en) * | 2011-05-04 | 2011-09-21 | 上海大学 | Dealloying preparation method capable of greatly reducing the size of a nanoporous metal skeleton |
| CN101717972B (en) * | 2009-11-26 | 2011-11-23 | 济南大学 | Electrochemical preparation method of nano porous palladium |
| CN102296349A (en) * | 2011-07-06 | 2011-12-28 | 上海大学 | De-alloying preparation method of nanometer porous metal substrate with surface enhanced Raman scattering activity |
| CN102602982A (en) * | 2012-03-14 | 2012-07-25 | 西安理工大学 | Method for preparing porous ZnO by means of combining dealloying method with ceramic coating |
| CN102644050A (en) * | 2012-04-16 | 2012-08-22 | 西安理工大学 | Method for preparing porous AlN/GaN film |
| CN104419840A (en) * | 2013-09-01 | 2015-03-18 | 济南大学 | Anti-supported nanoporous gold and metal oxide composite material and method for preparing same |
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| CN106024975A (en) * | 2016-06-03 | 2016-10-12 | 天津大学 | Preparation method of nano-porous molybdenum foil based molybdenum/platinum/silver laminar composite material |
| CN107892324A (en) * | 2017-11-10 | 2018-04-10 | 西安理工大学 | A kind of preparation method of ZnO nanowire array |
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| CN102191399A (en) * | 2011-05-04 | 2011-09-21 | 上海大学 | Dealloying preparation method capable of greatly reducing the size of a nanoporous metal skeleton |
| CN102296349A (en) * | 2011-07-06 | 2011-12-28 | 上海大学 | De-alloying preparation method of nanometer porous metal substrate with surface enhanced Raman scattering activity |
| CN102602982A (en) * | 2012-03-14 | 2012-07-25 | 西安理工大学 | Method for preparing porous ZnO by means of combining dealloying method with ceramic coating |
| CN102644050A (en) * | 2012-04-16 | 2012-08-22 | 西安理工大学 | Method for preparing porous AlN/GaN film |
| CN102644050B (en) * | 2012-04-16 | 2014-01-08 | 西安理工大学 | Method for preparing porous AlN/GaN film |
| CN104419840A (en) * | 2013-09-01 | 2015-03-18 | 济南大学 | Anti-supported nanoporous gold and metal oxide composite material and method for preparing same |
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