A kind of silver/polymer/silver/graphene core-shell nano mushroom material and preparation method thereof
And application
Technical field
The present invention relates to material engineering and field of nanometer technology, more particularly, to a kind of silver/polymer/silver/graphene core
Shell nanometer mushroom material and its preparation method and application.
Background technology
In past 20 years, due to the sensitivity with unimolecule rank, SERS(SERS)Technology
Have been developed as life health care, the efficient analysis detection means in the field such as environmental monitoring and food security.In various SERS materials
In material, the advantage of noble metal nanometer material is its surface plasma body resonant vibration(LSPR)It can induce and produce extremely strong local electricity
Magnetic field, shows excellent enhancing characteristic.In these noble metal nanometer materials, silver is with its preferably enhancing characteristic and simply system
Standby technique is shown one's talent.By using polytype surfactant, people have been prepared for receiving with diversified silver
Rice material, such as nanometer rods, nanocube, nanometer sheet and nanometer magnitude.By the structure and shape that change these silver nano materials
Looks, people can effectively adjust its surface plasma bulk properties and obtain more excellent optical property.But, due to wherein not
Containing nano gap, single silver nano-grain, its SERS signal is in general too weak to be used for Single Molecule Detection.Meanwhile,
The efficiency and reliability of SERS nano-probes are frequently subjected to the infringement of dissociation of ligand or exchange.Therefore, various optics inert materials
Such as silica and polymer be used to wrap up the stability that silver nano-grain improves Raman molecular.However, exposed to air
In silver nano material easily be oxidized, it is difficult to use it for making the SERS substrates of long-acting stabilization.Therefore, these silver nanoparticle materials
The practical application of material is severely limited.In addition, except the output signal of high intensity, the uniformity of other performances such as signal and
Stability is also most important for the practical application of SERS substrates.As a kind of two-dimension nano materials, graphene has good
Chemical inertness, wider printing opacity bands of a spectrum, excellent electromagnetic signal enhancing characteristic, this causes the composite of noble metal and graphene
Ideal chose as SERS substrates.Therefore, novel silver-polymer-graphite alkene is made using advanced nano-fabrication technique
Composite, to obtain the technical problem that more preferable SERS performances are current detection field urgent need to resolve.
The content of the invention
The technical problems to be solved by the invention are to provide a kind of silver/polymerization of the SERS signal output with very high strength
Thing/silver/graphite alkene core-shell nano mushroom material and its preparation method and application.
The present invention solve the technical scheme that is used of above-mentioned technical problem for:A kind of silver/polymer/silver/graphene nucleocapsid
Nanometer mushroom material, the core-shell nano material is by silver nanoparticle kernel, the polymer covering layer for being wrapped in silver nanoparticle core surface, position
In the silver nanoparticle outer layer and the graphene shell for being wrapped in polymer covering layer and silver nanoparticle superficies of polymer overmold layer surface
Four part of layer composition, wherein described silver nanoparticle kernel is the silver nano-grain of 10-20 nanometers of particle diameter, described polymer overmold
Layer is the polystyrene polyacrylic acid block copolymer layer of 8-13 nanometers of thickness, and described silver nanoparticle outer layer is received for particle diameter 20-60
The mushroom head silver nano-grain of rice, the thickness of described graphene shell is 10 nanometers.
The preparation method of above-mentioned silver/polymer/silver/graphene core-shell nano mushroom material, it is characterised in that including following
Step:
1)The preparation of silver nanoparticle core:Sodium citrate and silver nitrate are dissolved in water mixed solution is made, side is stirred vigorously at room temperature
Side adds ascorbic acid, after reaction terminates for 5 minutes, collected after centrifugation precipitation, produces silver nanoparticle core;
2)The preparation of silver/polymer core shell nanometer material:Take step 1)Obtained silver nanoparticle core is added to containing Raman molecular 2-
In the dimethylformamide in water of thionaphthol and polystyrene polyacrylic acid block copolymer, and oil bath is placed in after being stirred vigorously
In pot, in being heated 2 hours at 110 DEG C, room temperature is slowly dropped to afterwards, collected after centrifugation precipitation produces silver/polyalcohol nucleocapsid nanometer
Material;
3)The preparation of silver/polymer/silver core-shell nano material:By step 2)Obtained silver/polymer core shell nanometer material is dissolved in
In silver nitrate and sodium citrate are dissolved in the mixed liquor that water is made, aqueous ascorbic acid is slowly added dropwise while stirring, in room temperature
Lower reaction 1 hour, after reaction terminates, collected after centrifugation precipitation produces silver/polymer/silver core-shell nano material;
4)The preparation of silver/polymer/silver/graphene core-shell nano mushroom material:By step 3)Obtained silver/polymer/silver core
Shell nanometer material is dissolved in cysteamine and graphene are dissolved in the mixed liquor that water is made, and is slowly stirred 12 hours at room temperature, instead
After should terminating, collected after centrifugation precipitation produces silver/polymer/silver graphene core-shell nano mushroom material.
Step 1)Specially:10-20 milligrams of sodium citrates and 30-60 milligrams of silver nitrates are dissolved in 50 milliliters of water mixing is made
Solution, adds 20-40 milligrams of ascorbic acid when being stirred vigorously at room temperature, and after reaction terminates for 5 minutes, collected after centrifugation sinks
Form sediment, produce silver nanoparticle core.
Step 2)Specially:By step 1)Obtained whole silver nanoparticle cores are added to containing 0.05-0.1 milligrams of Raman moleculars
2- thionaphthols and 0.5-1 milligrams of polystyrene polyacrylic acid block copolymers by 900-1800 microlitres of dimethylformamide and
It is placed in the mixed liquor of 200-400 microlitres of deionized water composition, and after being stirred vigorously in oil bath pan in being heated 2 hours at 110 DEG C,
Room temperature is slowly dropped to afterwards, and collected after centrifugation precipitation produces silver/polymer core shell nanometer material.
Step 3)Specially:By step 2)Obtained whole silver/polymer core shell nanometer material is dissolved in by 2-4 milligrams of nitric acid
Silver and 6-12 milligrams of sodium citrates are dissolved in the 9-18 milliliter mixed liquors that water is made, and 2-4 milliliters dense is slowly added dropwise while stirring
The aqueous ascorbic acid for 2 milligrams every milliliter is spent, is reacted 1 hour at room temperature, after reaction terminates, collected after centrifugation precipitation,
Produce silver/polymer/silver core-shell nano mushroom material.
Step 4)Specially:By step 3)Obtained whole silver/polymer/silver core-shell nano material is dissolved in micro- by 20-40
MM cysteamine and 0.02-0.2 milligrams of graphenes are dissolved in 2 milliliters of mixed liquors that water is made, and 12 are slowly stirred at room temperature
Hour, after reaction terminates, collected after centrifugation precipitation produces silver/polymer/silver graphene core-shell nano mushroom material.
Step 1)-3)Middle centrifugal speed is 5000-15000 revs/min, and centrifugation time is 5-30 minutes.
The application of above-mentioned silver/polymer/silver/graphene core-shell nano mushroom material, described core-shell nano mushroom material
In the purposes of enhancing SERS signal output facet.
Compared with prior art, the advantage of the invention is that:Present invention firstly discloses it is a kind of with SERS activity silver/
Polymer/silver/graphene core-shell nano mushroom material, the core-shell nano material is by silver nanoparticle kernel, polymer second layer, silver the
Three layers and the part of graphene shell four composition, with novel multi-layer core-shell structure and novel mushroom-shaped structure(Institute between nucleocapsid
The larger tip location of a large amount of nano gaps and the curvature of mushroom-shaped structure that have can be with the presence of external exciting light
Produce substantial amounts of SERS focuses), wherein amphipathic block copolymer, particularly polystyrene acrylic acid block copolymer due to
With good translucency, the output without influenceing SERS signal.In addition, it forms exposed hydrophily official after clad
Can group can adsorb silver ion and silver-colored shell outside being formed in the presence of the reducing agent, it is inside and outside by very thin polymer shell
The plasmon coupling of silver layer will cause strong electromagnetic hotspot, causes the extreme of SERS signal and strengthens.
Silver/composite nano-polymers material that the present invention is prepared using Seed inducement method, with a distance of an only 10 nanometers left sides
Right inside and outside two layers of noble silver nano particle, in the presence of external exciting light, the surface local electromagnetic field that they are produced it
Between can intercouple effect, hot spot region is produced, while being further enhanced using what graphene had to Raman signal
Effect, produce with very high strength SERS signal export.Preparation technology of the present invention is simple, and the cycle is short, and yield is high, it is easy to push away
Wide and large-scale production.
Brief description of the drawings
Fig. 1 is the transmission electron microscope photo of the silver nanoparticle core prepared in the embodiment of the present invention 1;
Fig. 2 is the transmission electron microscope photo of the silver/polymer core shell nanometer material prepared in the embodiment of the present invention 1;
Fig. 3 is the transmission electron microscope photo of the silver/polymer/silver core-shell nano material prepared in the embodiment of the present invention 1;
The transmitted electron of silver/polymer/silver/graphene core-shell nano mushroom materials of the Fig. 4 to be prepared in the embodiment of the present invention 1 shows
Micro mirror photo;
Fig. 5 is to be examined using the Raman of the silver/polymer/silver prepared in the embodiment of the present invention 1/graphene core-shell nano mushroom material
Survey result;
The transmitted electron of silver/polymer/silver/graphene core-shell nano mushroom materials of the Fig. 6 to be prepared in the embodiment of the present invention 2 shows
Micro mirror photo;
Fig. 7 is to be examined using the Raman of the silver/polymer/silver prepared in the embodiment of the present invention 2/graphene core-shell nano mushroom material
Survey result;
The transmitted electron of silver/polymer/silver/graphene core-shell nano mushroom materials of the Fig. 8 to be prepared in the embodiment of the present invention 3 shows
Micro mirror photo;
Fig. 9 is to be examined using the Raman of the silver/polymer/silver prepared in the embodiment of the present invention 3/graphene core-shell nano mushroom material
Survey result.
Embodiment
The present invention is described in further detail below in conjunction with accompanying drawing embodiment.
Following examples are used to illustrate the present invention, but are not limited to the scope of the present invention.Unless otherwise specified, embodiment
In the conventional meanses that are well known to those skilled in the art of used technological means, raw materials used is commercial goods.Embodiment
The middle Raman spectrum detector BWS415 used is purchased from Bi Da Imtech of the U.S.(B&W Tek Inc.).
Embodiment 1
The preparation method of silver/polymer/silver/graphene core-shell nano mushroom material with SERS activity comprises the following steps:
1st, 10 milligrams of sodium citrates and 30 milligrams of silver nitrates are dissolved in 50 milliliters of water and mixed solution is made, side is violent at room temperature
Stir side and add 20 milligrams of ascorbic acid, after reaction terminates for 5 minutes, collect and precipitate after being centrifuged 20 minutes with 10000 revs/min,
Produce silver nanoparticle core;
2nd, whole silver nanoparticle cores made from above-mentioned steps are taken to be added to containing 0.05 milligram of Raman molecular 2- thionaphthol and 0.5 milligram
The dimethylformamide of polystyrene polyacrylic acid block copolymer(900 microlitres)And deionized water(200 microlitres)Mixed solution
In and be placed in oil bath pan after being stirred vigorously, in being heated 2 hours at 110 DEG C, room temperature is slowly dropped to afterwards, with 10000 revs/min
Centrifugation collects precipitation after 20 minutes, produces silver/polymer core shell nanometer material;
3rd, whole silver/polymer core shell nanometer materials made from above-mentioned steps are dissolved in by 2 milligrams of silver nitrates and 6 milligrams of citric acids
Sodium is dissolved in 9 milliliters of mixed liquors that water is made, and the aqueous solution of 2 milliliters of ascorbic acid is slowly added dropwise while stirring(Ascorbic acid is dense
Spend for 2 milligrams every milliliter), react 1 hour, after reaction terminates, collected after being centrifuged 20 minutes with 10000 revs/min at room temperature
Precipitation, produces silver/polymer/silver core-shell nano mushroom material;
4th, take made from above-mentioned steps whole silver/polymer/silver core-shell nano materials be dissolved in by 20 micro- mMs of cysteamines and
0.02 milligram of graphene is dissolved in 2 milliliters of mixed liquors that water is made, and is slowly stirred at room temperature 12 hours, after reaction terminates, from
Precipitation is collected after the heart, silver/polymer/silver graphene core-shell nano mushroom material is produced.
The core-shell nano material prepared in the present embodiment by silver nanoparticle kernel, be wrapped in the polymer of silver nanoparticle core surface
Clad, the silver nanoparticle outer layer positioned at polymer overmold layer surface and it is wrapped in polymer covering layer and silver nanoparticle superficies
The part group of graphene shell four, wherein kernel are the silver nano-grain of 15-20 nanometers of particle diameter, and polymer covering layer is that thickness 13 is received
The polystyrene polyacrylic acid block copolymer layer of rice, silver nanoparticle outer layer is the mushroom head silver nanoparticle of 40-60 nanometers of particle diameter
Grain, the thickness of graphene shell is 10 nanometers.
Fig. 1 shows the transmission electron microscope photo of the silver nanoparticle core prepared in the present embodiment.
Fig. 2 shows the transmission electron microscope photo of the silver/polymer core shell nanometer material prepared in the present embodiment, from
Fig. 2 can be seen that prepared silver nanoparticle core and be wrapped up by one layer of intimate transparent polymeric shell layer.
Fig. 3 shows that the transmission electron microscope of the silver/polymer/silver core-shell nano material prepared in the present embodiment shines
Piece, figure it is seen that the surface of silver/polymer core shell nanometer material has the mushroom head silver nanoparticle of 40-60 nanometers of particle diameter
Particle.
Fig. 4 shows that the novel silver/polymer/silver/graphene nucleocapsid with SERS activity prepared in the present embodiment is received
The transmission electron microscope photo of rice mushroom material, from fig. 4, it can be seen that prepared nano material is mushroom-shaped structure.
Fig. 5 is the novel silver/polymer/silver/graphene nucleocapsid with SERS activity prepared using the above method
Nanometer mushroom material Raman spectrogram.From fig. 5, it can be seen that the SERS active materials have good SERS signal enhancing effect
Should, it is in 1064 cm-1The Raman signal intensity at place reaches 26400.
Embodiment 2
The preparation method of silver/polymer/silver/graphene core-shell nano mushroom material with SERS activity comprises the following steps:
1st, it is dissolved in 50 milliliters of water with 15 milligrams of sodium citrates and 45 milligrams of silver nitrates and mixed solution is made, side is acutely stirred at room temperature
Mix side and add 30 milligrams of ascorbic acid, after reaction terminates for 5 minutes, collect and precipitate after being centrifuged 30 minutes with 5000 revs/min, produce
Silver nanoparticle core;
2nd, whole silver nanoparticle cores made from above-mentioned steps are taken to be added to containing 0.075 milligram of Raman molecular 2- thionaphthol and 0.75 milli
The dimethylformamide of gram polystyrene polyacrylic acid block copolymer(1350 microlitres)And deionized water(300 microlitres)Mixing is molten
It is placed in liquid, and after being stirred vigorously in oil bath pan in being heated 2 hours at 110 DEG C, room temperature is slowly dropped to afterwards, with 5000 revs/min
Zhongli's heart collects precipitation in 30 minutes, produces silver/polymer core shell nanometer material;
3rd, whole silver/polymer core shell nanometer materials made from above-mentioned steps are taken to be dissolved in by 3 milligrams of silver nitrates and 9 milligrams of citric acids
Sodium is dissolved in 13.5 milliliters of mixed liquors that water is made, and the aqueous solution of 3 milliliters of ascorbic acid is slowly added dropwise while stirring(Ascorbic acid
Concentration be 2 milligrams every milliliter), react 1 hour at room temperature, after reaction terminates, after being centrifuged 30 minutes with 5000 revs/min
Precipitation is collected, silver/polymer/silver core-shell nano mushroom material is produced.
4th, whole silver/polymer/silver core-shell nano materials made from above-mentioned steps are taken to be dissolved in by 15 micro- mMs of cysteamines
It is dissolved in 2 milliliters of mixed liquors that water is made, is slowly stirred at room temperature 12 hours with 0.05 milligram of graphene, after reaction terminates,
Collected after centrifugation is precipitated, and produces silver/polymer/silver graphene core-shell nano mushroom material.
The core-shell nano material prepared in the present embodiment by silver nanoparticle kernel, be wrapped in the polymer of silver nanoparticle core surface
Clad, the silver nanoparticle outer layer positioned at polymer overmold layer surface and it is wrapped in polymer covering layer and silver nanoparticle superficies
The part group of graphene shell four, wherein, kernel is the silver nano-grain of 10-15 nanometers of particle diameter, and polymer covering layer is that thickness 8 is received
The polystyrene polyacrylic acid block copolymer layer of rice, silver nanoparticle outer layer is the mushroom head silver nanoparticle of 30-50 nanometers of particle diameter
Grain, the thickness of graphene shell is 10 nanometers.
Fig. 6 shows that the novel silver/polymer/silver/graphene nucleocapsid with SERS activity prepared in the present embodiment is received
The transmission electron microscope photo of rice mushroom material, from fig. 6, it can be seen that prepared nano material is mushroom-shaped structure.
Fig. 7 is the novel silver/polymer/silver/graphene nucleocapsid with SERS activity prepared using the above method
The Raman spectrogram of nanometer mushroom material.From figure 7 it can be seen that the SERS active materials have good SERS signal enhancing
Effect, it is in 1064 cm-1The Raman signal intensity at place reaches 20000.
Embodiment 3
The preparation method of silver/polymer/silver/graphene core-shell nano mushroom material with SERS activity, comprises the following steps:
1st, it is dissolved in 50 milliliters of water with 20 milligrams of sodium citrates and 60 milligrams of silver nitrates and mixed solution is made, side is acutely stirred at room temperature
Mix side and add 40 milligrams of ascorbic acid, after reaction terminates for 5 minutes, collect and precipitate after being centrifuged 5 minutes with 15000 revs/min, produce
Silver nanoparticle core;
2nd, whole silver nanoparticle cores made from above-mentioned steps are taken to be added to poly- containing 0.1 milligram of Raman molecular 2- thionaphthol and 1 milligram
The dimethylformamide of styrene polyacrylic acid block copolymer(1800 microlitres)And deionized water(400 microlitres)Mixed solution
In, and be placed in oil bath pan in being heated 2 hours at 110 DEG C after being stirred vigorously, room temperature is slowly dropped to afterwards, with 15000 revs/min
Centrifugation collects precipitation in 5 minutes, produces silver/polymer core shell nanometer material;
3rd, whole silver/polymer core shell nanometer materials made from above-mentioned steps are taken to be dissolved in by 4 milligrams of silver nitrates and 12 milligrams of lemons
Sour sodium is dissolved in 18 milliliters of mixed liquors that water is made, and the aqueous solution of 4 milliliters of ascorbic acid is slowly added dropwise while stirring(Ascorbic acid
Concentration be 2 milligrams every milliliter), react 1 hour, after reaction terminates, received after being centrifuged 5 minutes with 15000 revs/min at room temperature
Collection precipitation, produces silver/polymer/silver core-shell nano mushroom material;
4th, whole silver/polymer/silver core-shell nano materials made from above-mentioned steps are taken to be dissolved in by 40 micro- mMs of cysteamines and 0.2
Milligram graphene is dissolved in 2 milliliters of mixed liquors that water is made, and is slowly stirred at room temperature 12 hours, after reaction terminates, after centrifugation
Precipitation is collected, silver/polymer/silver graphene core-shell nano mushroom material is produced.
The core-shell nano material prepared in the present embodiment by silver nanoparticle kernel, be wrapped in the polymer of silver nanoparticle core surface
Clad, the silver nanoparticle outer layer positioned at polymer overmold layer surface and it is wrapped in polymer covering layer and silver nanoparticle superficies
The part group of graphene shell four, wherein, kernel is the silver nano-grain of 15-20 nanometers of particle diameter, and polymer covering layer is thickness 10
The polystyrene polyacrylic acid block copolymer layer of nanometer, silver nanoparticle outer layer is the mushroom head silver nanoparticle of 20-60 nanometers of particle diameter
Particle, the thickness of graphene shell is 10 nanometers.
Fig. 8 shows that the novel silver/polymer/silver/graphene nucleocapsid with SERS activity prepared in the present embodiment is received
The transmission electron microscope photo of rice mushroom material, from figure 8, it is seen that prepared nano material is four layers of core shell structure.
Fig. 9 is the novel silver/polymer/silver/graphene nucleocapsid with SERS activity prepared using the above method
The Raman spectrogram of nanometer mushroom material.From fig. 9, it can be seen that the SERS active materials have good SERS signal enhancing
Effect, it is in 1064 cm-1The Raman signal intensity at place reaches 17000.
Although above the present invention is described in detail with a general description of the specific embodiments,
On the basis of the present invention, it can be made some modifications or improvements, this will be apparent to those skilled in the art.Cause
This, these modifications or improvements, belong to the scope of protection of present invention without departing from theon the basis of the spirit of the present invention.