CN109765209B - Preparation method and application of bifunctional expanded graphite/nanogold composite electrode - Google Patents
Preparation method and application of bifunctional expanded graphite/nanogold composite electrode Download PDFInfo
- Publication number
- CN109765209B CN109765209B CN201910050736.2A CN201910050736A CN109765209B CN 109765209 B CN109765209 B CN 109765209B CN 201910050736 A CN201910050736 A CN 201910050736A CN 109765209 B CN109765209 B CN 109765209B
- Authority
- CN
- China
- Prior art keywords
- electrode
- graphite
- pencil lead
- composite electrode
- fluffy
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 73
- 229910002804 graphite Inorganic materials 0.000 title claims abstract description 63
- 239000010439 graphite Substances 0.000 title claims abstract description 63
- 239000002131 composite material Substances 0.000 title claims abstract description 35
- 230000001588 bifunctional effect Effects 0.000 title claims abstract description 15
- 238000002360 preparation method Methods 0.000 title claims abstract description 10
- 239000010931 gold Substances 0.000 claims abstract description 28
- 239000002105 nanoparticle Substances 0.000 claims abstract description 18
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 claims abstract description 14
- 239000008103 glucose Substances 0.000 claims abstract description 14
- 229910052737 gold Inorganic materials 0.000 claims abstract description 14
- 238000004416 surface enhanced Raman spectroscopy Methods 0.000 claims abstract description 14
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims abstract description 9
- 238000001514 detection method Methods 0.000 claims abstract description 8
- 239000000463 material Substances 0.000 claims abstract description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 17
- 239000008151 electrolyte solution Substances 0.000 claims description 16
- 238000000034 method Methods 0.000 claims description 16
- 238000001035 drying Methods 0.000 claims description 14
- 238000005406 washing Methods 0.000 claims description 14
- 239000002253 acid Substances 0.000 claims description 12
- ZOMNIUBKTOKEHS-UHFFFAOYSA-L dimercury dichloride Chemical class Cl[Hg][Hg]Cl ZOMNIUBKTOKEHS-UHFFFAOYSA-L 0.000 claims description 11
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims description 11
- 239000000243 solution Substances 0.000 claims description 11
- 229910004042 HAuCl4 Inorganic materials 0.000 claims description 10
- 238000004070 electrodeposition Methods 0.000 claims description 10
- 239000012452 mother liquor Substances 0.000 claims description 10
- 239000003292 glue Substances 0.000 claims description 7
- 239000007832 Na2SO4 Substances 0.000 claims description 6
- 238000002484 cyclic voltammetry Methods 0.000 claims description 6
- 229910052938 sodium sulfate Inorganic materials 0.000 claims description 6
- 230000003197 catalytic effect Effects 0.000 claims description 4
- 238000010408 sweeping Methods 0.000 claims description 4
- 230000003647 oxidation Effects 0.000 claims description 3
- 238000007254 oxidation reaction Methods 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 claims 2
- 230000004044 response Effects 0.000 abstract description 12
- 230000015572 biosynthetic process Effects 0.000 abstract description 5
- 239000000523 sample Substances 0.000 abstract description 5
- 238000003786 synthesis reaction Methods 0.000 abstract description 5
- 230000035945 sensitivity Effects 0.000 abstract description 4
- 238000006555 catalytic reaction Methods 0.000 abstract description 3
- 238000011065 in-situ storage Methods 0.000 abstract description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- 238000001069 Raman spectroscopy Methods 0.000 description 5
- 238000002441 X-ray diffraction Methods 0.000 description 5
- 229910021389 graphene Inorganic materials 0.000 description 5
- VYXSBFYARXAAKO-UHFFFAOYSA-N ethyl 2-[3-(ethylamino)-6-ethylimino-2,7-dimethylxanthen-9-yl]benzoate;hydron;chloride Chemical compound [Cl-].C1=2C=C(C)C(NCC)=CC=2OC2=CC(=[NH+]CC)C(C)=CC2=C1C1=CC=CC=C1C(=O)OCC VYXSBFYARXAAKO-UHFFFAOYSA-N 0.000 description 4
- 239000003792 electrolyte Substances 0.000 description 3
- 239000000758 substrate Substances 0.000 description 3
- 238000004458 analytical method Methods 0.000 description 2
- 239000003575 carbonaceous material Substances 0.000 description 2
- 230000005284 excitation Effects 0.000 description 2
- 238000001000 micrograph Methods 0.000 description 2
- 239000002086 nanomaterial Substances 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 238000006722 reduction reaction Methods 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 230000027756 respiratory electron transport chain Effects 0.000 description 2
- 238000000479 surface-enhanced Raman spectrum Methods 0.000 description 2
- 230000002194 synthesizing effect Effects 0.000 description 2
- XMWRBQBLMFGWIX-UHFFFAOYSA-N C60 fullerene Chemical class C12=C3C(C4=C56)=C7C8=C5C5=C9C%10=C6C6=C4C1=C1C4=C6C6=C%10C%10=C9C9=C%11C5=C8C5=C8C7=C3C3=C7C2=C1C1=C2C4=C6C4=C%10C6=C9C9=C%11C5=C5C8=C3C3=C7C1=C1C2=C4C6=C2C9=C5C3=C12 XMWRBQBLMFGWIX-UHFFFAOYSA-N 0.000 description 1
- 238000003556 assay Methods 0.000 description 1
- 239000008280 blood Substances 0.000 description 1
- 210000004369 blood Anatomy 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000002134 carbon nanofiber Substances 0.000 description 1
- 239000011852 carbon nanoparticle Substances 0.000 description 1
- 239000002041 carbon nanotube Substances 0.000 description 1
- 229910021393 carbon nanotube Inorganic materials 0.000 description 1
- 239000000969 carrier Substances 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- VYXSBFYARXAAKO-WTKGSRSZSA-N chembl402140 Chemical compound Cl.C1=2C=C(C)C(NCC)=CC=2OC2=C\C(=N/CC)C(C)=CC2=C1C1=CC=CC=C1C(=O)OCC VYXSBFYARXAAKO-WTKGSRSZSA-N 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 230000005518 electrochemistry Effects 0.000 description 1
- 239000002659 electrodeposit Substances 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 229910003472 fullerene Inorganic materials 0.000 description 1
- 238000003384 imaging method Methods 0.000 description 1
- 238000010348 incorporation Methods 0.000 description 1
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical class C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000002057 nanoflower Substances 0.000 description 1
- 239000002070 nanowire Substances 0.000 description 1
- 238000011275 oncology therapy Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000005289 physical deposition Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Images
Landscapes
- Electrodes For Compound Or Non-Metal Manufacture (AREA)
- Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)
- Catalysts (AREA)
Abstract
The invention belongs to the technical field of nanogold sensors, and particularly relates to a preparation method and application of a bifunctional expanded pencil lead graphite/nanogold composite electrode. In the invention, mild voltage is applied to graphite to expand the edge of the graphite but not strip the graphite, so that a net-shaped fluffy graphite structure is obtained, and then gold nano particles are electrodeposited in situ to obtain the composite electrode. The fluffy graphene-like structure can provide a large specific surface area and a large number of binding sites; the gold nanoparticles have good electrocatalytic capacity and plasma characteristics, and show excellent performance in the aspects of glucose catalysis and SERS (surface enhanced Raman scattering) application. The composite electrode prepared by the invention overcomes the problems of poor response stability, low sensitivity and poor reproducibility caused by off-line synthesis and later-stage fixing materials. The composite electrode has a wider linear range, a lower detection limit and good reproducibility for glucose catalysis; has good SERS response to probe molecules, high sensitivity and good stability.
Description
Technical Field
The invention belongs to the technical field of nanogold sensors, and particularly relates to a preparation method and application of a bifunctional expanded graphite/nanogold composite electrode.
Background
Gold nanoparticles (AuNPs) are the most stable nanometal particles, and because of their unique optical, electronic, and photothermal conversion properties, AuNPs of certain shape and size are a hotspot in the research in the fields of sensors, Surface Enhanced Raman Scattering (SERS), imaging diagnostics, and photothermal cancer therapy.
Common methods for synthesizing AuNPs include chemical reduction, Brust-Schiffrin, physical and electrodeposition. The electrodeposition technology is rapid and easy to operate, and controllable synthesis of AuNPs with different shapes and sizes can be realized by adjusting the electrodeposition conditions.
AuNPs generally require the incorporation of other nanomaterials as carriers to further enhance their response properties. The most commonly used support materials are high specific area carbon nanomaterials including fullerenes, graphene, carbon nanofibers and carbon nanotubes. For example, carbon nanoparticles, nanoflowers, nanowire-bound AuNPs are widely used in the field of glucose sensors due to their large specific surface area and good catalytic ability. Meanwhile, the plasma characteristics of AuNPs can generate a 'hot spot' strong electric field, thereby realizing Raman detection of trace or trace substances. However, the synthesis of these carbon materials is expensive and cumbersome, and the off-line synthesis and later re-modification process results in poor sensor stability. Recently, Parvez reported a method of electrochemically exfoliating graphite into graphene by applying a DC voltage of + 10V in an inorganic electrolyte. They believe that the application of a high voltage of 10V can cause the edges of the graphite to expand first and increase the cracks in the graphite layers, subsequently causing a large number of graphene sheets to flake off and fall into the electrolyte solution.
According to the invention, after a mild voltage is applied to graphite, the edge of the graphite is expanded but not stripped, so that a fluffy graphite structure of the net-shaped three-dimensional graphene is obtained, and gold nanoparticles are electrodeposited in situ on the basis, so that a composite electrode is obtained and is applied to the electrochemistry of glucose and response in the SERS field.
Disclosure of Invention
The invention aims to provide a preparation method and application of a bifunctional expanded pencil lead graphite/nanogold composite electrode.
The invention provides a preparation method of a difunctional expanded pencil lead graphite/nanogold composite electrode, which comprises the following specific steps:
(1) commercially available pencil leads (e.g., HB of morning light or Mitsubishi, 2B,4B,6B,8B, etc.) having a high graphite content (80% by mass or more) are insulated with AB glue to keep the conductive part at a fixed length (e.g., 1cm or less, with a better signal-to-noise ratio), rinsed with secondary water, and dried at room temperature;
(2) using a conventional three-electrode system at 0.05-0.1M Na2SO4In the electrolyte solution, taking the pencil lead as a working electrode, a platinum wire as a counter electrode and saturated calomel as a reference electrode, and carrying out potentiostatic method treatment, wherein the potentiostatic is 2-3V, and the duration is 200-300 s, so as to obtain the pencil lead graphite electrode with a fluffy surface; taking out, washing with secondary water, and drying at room temperature;
(3) 1g of HAuCl4•4H2Dissolving O in a 100mL volumetric flask to obtain chloroauric acid mother liquor with a certain concentration (the chloroauric acid is prepared into a solution which is convenient to store and use later); 0.53-2.17 mLHAuCl is taken from chloroauric acid mother liquor4Dispersing the solution in 10 mLPBS solution with pH value of 7-7.5 to be used as electrolyte solution;
(4) using a conventional three-electrode system in HAuCl4In the electrolyte solution, performing electrodeposition on Au nano particles by using a graphite electrode with a fluffy surface as a working electrode, a platinum wire electrode as a counter electrode and a saturated calomel electrode as a reference electrode; performing electrodeposition on Au nano particles by adopting cyclic voltammetry, and circulating for 20-200 circles at a sweeping speed of 0.025-0.4V/s to obtain a fluffy pencil lead graphite/nano gold composite electrode (marked as EPLE/AuNPs); and washed with secondary water and dried at room temperature.
In the step (1), the lead graphite electrode is insulated by AB glue and used for obtaining the lead graphite electrode with a fixed specific surface area.
In the step (2), the obtained pencil lead graphite electrode with a fluffy surface has a large specific surface area, the electron transfer rate is accelerated, and more binding sites are provided for the deposition of Au nanoparticles.
In the step (3), the concentration of the chloroauric acid electrolyte solution is controlled to be 1.28-5.28 mu mol/L.
In the step (4), the potential of the Au nano particles electrodeposited by the cyclic voltammetry is as follows: -0.6-0.8V.
In the step (4), Au nano particles are deposited, so that the surface structure of the electrode is improved, and the biocompatibility and the electronic property of the surface of the electrode are improved.
The bifunctional composite electrode prepared by the method is characterized in that: fluffy pencil lead graphite obtained by the pencil lead graphite electrode through constant potential electrochemical treatment is used as a substrate material; the three-dimensional graphene-like structure of the fluffy pencil lead graphite provides a large specific surface area and a large number of binding sites; the gold nanoparticles have good electrocatalytic capacity and plasma characteristics, and show excellent performance in the aspects of glucose catalysis and SERS (surface enhanced Raman scattering) application.
The prepared difunctional graphite/nanogold composite electrode for the expanded pencil lead can be applied to the aspects of electrochemical catalytic oxidation and SERS of glucose, and can realize detection of glucose in human blood and SERS stable response of trace Raman probe molecules R6G.
The invention has the advantages that: the fluffy graphite electrode obtained by constant potential electrochemical treatment is simple and quick, has low cost and avoids the complicated process of synthesizing the carbon material. The three-dimensional graphene-like structure of the fluffy graphite electrode provides a large specific surface area and attachment sites, and the electron transfer rate is further accelerated. In addition, the in-situ electrodeposition technique is a method that can prepare AuNPs having different sizes, morphologies and compositions by adjusting the operating conditions, and can accomplish the preparation and fixation of the material at the same time. The integrated composite electrode constructed by the invention overcomes the problems of poor response stability, low sensitivity and poor reproducibility caused by off-line synthesis and later-stage fixing materials. The composite electrode has good catalytic action on the oxidation of glucose, wide response linear range, low detection limit and good reproducibility. In addition, the composite electrode has good SERS response to Raman probe molecules, high sensitivity and good stability.
Drawings
Fig. 1 is a scanning electron microscope image of the bifunctional fluffy pencil lead graphite electrode provided in example 1.
Fig. 2 is an X-ray diffraction pattern of the bifunctional fluffy pencil-lead graphite and the pencil-lead graphite electrode provided in example 1.
Fig. 3 is a scanning electron microscope image of the bifunctional fluffy pencil-lead graphite/nanogold composite electrode provided in example 2.
Fig. 4 is an X-ray diffraction pattern of the bifunctional fluffy pencil-lead graphite/nanogold composite electrode provided in example 2.
Fig. 5 is an amperometric response plot of glucose in 0.1M NaOH for the bifunctional fluffy pencil-lead graphite/nanogold composite electrode provided in example 3.
Fig. 6 is a linear fit plot between amperometric response and glucose concentration of the bifunctional fluffy pencil-lead graphite/nanogold composite electrode provided in example 3.
Fig. 7 is a SERS spectrum of the bifunctional fluffy pencil-lead graphite/nanogold composite electrode substrate provided in example 4 for different concentrations of R6G.
FIG. 8 shows a pair of 10 pairs of multifunctional fluffy pencil lead graphite/nano-gold composite electrode substrates randomly drawn at different positions according to example 4 of the present invention-6M R6G.
Detailed Description
The present invention will be described in detail with reference to the following embodiments in order to make the aforementioned objects, features and advantages more comprehensible
Example 1:
(1) insulating Mitsubishi 2B pencil lead (diameter 0.5 mm) with AB glue to keep the conductive part length at 0.5cm, washing with secondary water, and drying at room temperature;
(2) using a conventional three-electrode system at 0.1M Na2SO4In the electrolyte solution, a pencil lead electrode is used as a working electrode, a platinum wire electrode is used as a counter electrode, and a saturated calomel electrode is used as a reference electrode;
(3) and (3) adopting a constant potential method, keeping the constant potential of 2V for 300s to obtain a pencil lead graphite electrode with a fluffy surface, taking out, washing with secondary water, and drying at room temperature.
Observing the prepared fluffy pencil lead graphite under a Scanning Electron Microscope (SEM), and finding that the fluffy pencil lead graphite surface becomes rougher to form a 3D-like graphene sample surface. Indicating an increase in the specific surface area of the potentiostatic electrochemically treated fluffy pencil lead graphite electrode (EPLE), as shown in fig. 1. To further determine the structure of the pencil lead graphite after electrochemical treatment, the prepared samples were subjected to X-ray diffraction pattern analysis. As shown in fig. 2, the XRD patterns of both electrodes showed sharp crystalline plane diffraction peaks of graphite (002) and graphite (004) at 26.5 ° and 54.7 °. Indicating that the potentiostatic electrochemical treatment did not alter the crystal structure of the graphite.
Example 2:
(1) insulating Mitsubishi 2B pencil lead (diameter 0.5 mm) with AB glue to keep the length of the conductive part at 0.5cm, washing with secondary water, and drying at room temperature;
(2) using a conventional three-electrode system at 0.1M Na2SO4In the electrolyte solution, a pencil lead electrode is used as a working electrode, a platinum wire electrode is used as a counter electrode, and a saturated calomel electrode is used as a reference electrode;
(3) adopting a potentiostatic method, keeping the constant potential of 2V for 300s to obtain a pencil lead graphite electrode with a fluffy surface, taking out, washing with secondary water, and drying at room temperature;
(4) 1g of HAuCl4•4H2O dissolved in 100mLH2In O, obtaining chloroauric acid mother liquor with a certain concentration;
(5) from the chloroauric acid mother liquor, 1.65mL of HAuCl was dispersed in 10mL of a PBS solution having a pH of 7.4 to give a concentration of 3.47. mu. mol/L4An electrolyte solution;
(6) using a conventional three-electrode system in HAuCl4In the electrolyte solution, a fluffy pencil lead graphite electrode is used as a working electrode, a platinum wire electrode is used as a counter electrode, and a saturated calomel electrode is used as a reference electrode to electrodeposit Au nano particles;
(7) and (3) circulating 150 circles at a sweep speed of 0.025V/s by adopting a cyclic voltammetry method to obtain a fluffy pencil lead graphite/nano-gold composite electrode (EPLE/AuNPs), washing with secondary water, and drying at room temperature.
The prepared fluffy pencil lead graphite/nano-gold composite electrode (EPLE/AuNPs) is placed under a Scanning Electron Microscope (SEM) to observe the shape and size of the material. Plum blossom-shaped Au clusters were found to form on the surface of the fluffy pencil lead graphite as shown in fig. 3. To further confirm the successful reduction of gold nanoparticles, the prepared samples were subjected to X-ray diffraction pattern analysis. Diffraction peaks at 38.29 degrees, 44.44 degrees, 64.69 degrees, 77.53 degrees and the like on the graph show that the gold nanoparticles are successfully reduced on the surface of the fluffy pencil-lead graphite electrode, as shown in fig. 4.
Example 3:
(1) insulating Mitsubishi 2B pencil lead (diameter 0.5 mm) with AB glue to keep the length of the conductive part at 0.5cm, washing with secondary water, and drying at room temperature;
(2) using a conventional three-electrode system at 0.1M Na2SO4In the electrolyte solution, a pencil lead electrode is used as a working electrode, a platinum wire electrode is used as a counter electrode, and a saturated calomel electrode is used as a reference electrode;
(3) adopting a potentiostatic method, keeping the constant potential of 2V for 300s to obtain a pencil lead graphite electrode with a fluffy surface, taking out, washing with secondary water, and drying at room temperature;
(4) 1g of HAuCl4•4H2O is dispersed in 100mLH2In O, obtaining chloroauric acid mother liquor with a certain concentration;
(5) from the chloroauric acid mother liquor, 1.65mL of HAuCl was dispersed in 10mL of a PBS solution having a pH of 7.4 to give a concentration of 3.47. mu. mol/L4An electrolyte;
(6) using a conventional three-electrode system in HAuCl4In the electrolyte solution, a fluffy pencil lead graphite electrode is used as a working electrode, a platinum wire electrode is used as a counter electrode, and a saturated calomel electrode is used as a reference electrode to carry out electrodeposition of Au nano particles;
(7) and (3) circulating for 100 circles at a sweeping speed of 0.05V/s by adopting a cyclic voltammetry method to obtain a fluffy pencil lead graphite/nano-gold composite electrode (EPLE/AuNPs), washing with secondary water, and drying at room temperature.
And carrying out an electrocatalysis experiment on the prepared EPLE/Au by taking glucose as a target catalyst, and investigating the electrocatalysis performance of the prepared composite electrode. Adding glucose solution of certain concentration into 0.1M NaOH solution under constant potential of +0.2V and stirringi-tThe amperometric response of the composite electrode was measured. The results show that the current response gradually increases with increasing glucose concentration, as shown in fig. 5. The linear range of the assay was 0.05 to 60 mM, R2=0.960, detection limit of 5 μ M (S/N =)3) As shown in fig. 6. The excellent electrocatalytic performance of the EPLE/AuNPs composite electrode is shown.
Example 4:
(1) insulating Mitsubishi 2B pencil lead (diameter 0.5 mm) with AB glue to keep the length of the conductive part at 0.5cm, washing with secondary water, and drying at room temperature;
(2) using a conventional three-electrode system at 0.1M Na2SO4In the electrolyte solution, a pencil lead electrode is used as a working electrode, a platinum wire electrode is used as a counter electrode, and a saturated calomel electrode is used as a reference electrode;
(3) adopting a potentiostatic method, keeping the constant potential of 2V for 300s to obtain a pencil lead graphite electrode with a fluffy surface, taking out, washing with secondary water, and drying at room temperature;
(4) 1g of HAuCl4•4H2O dissolved in 100mLH2In O, obtaining chloroauric acid mother liquor with a certain concentration;
(5) from the chloroauric acid mother liquor, 1.82mL of HAuCl was dispersed in 10mL of a PBS solution having a pH of 7.4 to give a concentration of 4.42. mu. mol/L4An electrolyte;
(6) using a conventional three-electrode system in HAuCl4In the electrolyte solution, a fluffy pencil lead graphite electrode is used as a working electrode, a platinum wire electrode is used as a counter electrode, and a saturated calomel electrode is used as a reference electrode to carry out electrodeposition of Au nano particles;
(7) and (3) circulating 150 circles at a sweeping speed of 0.05V/s by adopting a cyclic voltammetry method to obtain a fluffy pencil lead graphite/nano-gold composite electrode (EPLE/AuNPs), washing with secondary water, and drying at room temperature.
In order to research the SERS detection performance of the EPLE/Au, the EPLE/AuNPs composite electrode is soaked in rhodamine 6G solutions with different concentrations for 24 hours and then dried for standby. And collecting a SERS spectrum signal diagram under excitation of a 633nm excitation light source. As shown in fig. 7, the raman scattering intensity increases with increasing concentration of probe molecules. When the concentration was reduced to pM levels, a characteristic peak of R6G was still recognized. In addition, the raman signals at different sites on the electrode were randomly detected, and the relative standard deviation of the detection results was within 15%, as shown in fig. 8. The EPLE/AuNPs composite electrode has good reproducibility in SERS application.
Claims (6)
1. A preparation method of a difunctional expanded pencil lead graphite/nanogold composite electrode is characterized by comprising the following specific steps:
(1) insulating a commercially available pencil lead with the graphite mass content of more than 80% by using AB glue, keeping the conductive part at a fixed length, washing with secondary water, and drying at room temperature;
(2) using a three-electrode system at 0.05-0.1M Na2SO4In the electrolyte solution, taking the pencil lead as a working electrode, a platinum wire as a counter electrode and saturated calomel as a reference electrode, and carrying out potentiostatic method treatment, wherein the constant potential is controlled to be 2-3V, and the constant potential duration time is 200 plus materials for 300s, so as to obtain the pencil lead graphite electrode with a fluffy surface; taking out, washing with secondary water, and drying at room temperature;
(3) 1g of HAuCl4•4H2Dissolving O in a 100mL volumetric flask to obtain chloroauric acid mother liquor with a certain concentration; 0.53-2.17 mLHAuCl is taken from chloroauric acid mother liquor4Dispersing the solution in 10 mLPBS solution with pH of 7-7.5 to be used as electrolyte solution;
(4) using a three-electrode system in HAuCl4In the electrolyte solution, performing electrodeposition on Au nano particles by taking graphite with fluffy pencil leads on the surface as a working electrode, a platinum wire as a counter electrode and saturated calomel as a reference electrode; performing electrodeposition on Au nano particles by adopting cyclic voltammetry, and circulating for 20-200 circles at a sweeping speed of 0.025-0.4V/s to obtain a fluffy pencil lead graphite/nano gold composite electrode; and washed with secondary water and dried at room temperature.
2. The production method according to claim 1, wherein the pencil type in step (1) is HB,2B,4B,6B or 8B.
3. The production method according to claim 1, wherein the fixed length in step (1) is 1cm or less.
4. The preparation method according to claim 1, wherein the potential of the electrodeposited Au nanoparticles in the step (4) is controlled to be: -0.6-0.8V.
5. A bifunctional expanded pencil lead graphite/nanogold composite electrode obtained by the preparation method of any one of claims 1 to 4.
6. The bifunctional expanded pencil lead graphite/nanogold composite electrode as claimed in claim 5, which is applied to the fields of glucose catalytic oxidation and SERS detection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910050736.2A CN109765209B (en) | 2019-01-20 | 2019-01-20 | Preparation method and application of bifunctional expanded graphite/nanogold composite electrode |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910050736.2A CN109765209B (en) | 2019-01-20 | 2019-01-20 | Preparation method and application of bifunctional expanded graphite/nanogold composite electrode |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109765209A CN109765209A (en) | 2019-05-17 |
| CN109765209B true CN109765209B (en) | 2021-03-02 |
Family
ID=66454547
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910050736.2A Active CN109765209B (en) | 2019-01-20 | 2019-01-20 | Preparation method and application of bifunctional expanded graphite/nanogold composite electrode |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109765209B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115184424B (en) * | 2022-07-08 | 2024-01-16 | 湖南大学 | Method for detecting lead, detection electrode, electrochemical sensor and preparation method |
| CN115236152B (en) * | 2022-07-08 | 2024-03-08 | 湖南大学 | Method for simultaneously detecting lead and arsenic, detection electrode, electrochemical sensor and preparation method |
| CN117686480A (en) * | 2024-01-24 | 2024-03-12 | 深圳北理莫斯科大学 | Preparation method and application of high-performance flexible surface-enhanced Raman substrate |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101060038A (en) * | 2007-04-20 | 2007-10-24 | 哈尔滨工程大学 | Expanded graphite/metal oxide composite material and preparation method thereof |
| CN102645479A (en) * | 2012-04-19 | 2012-08-22 | 湖南大学 | Lead ion specific detection sensor and preparation method and using method thereof |
-
2019
- 2019-01-20 CN CN201910050736.2A patent/CN109765209B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101060038A (en) * | 2007-04-20 | 2007-10-24 | 哈尔滨工程大学 | Expanded graphite/metal oxide composite material and preparation method thereof |
| CN102645479A (en) * | 2012-04-19 | 2012-08-22 | 湖南大学 | Lead ion specific detection sensor and preparation method and using method thereof |
Non-Patent Citations (1)
| Title |
|---|
| Fully printed one-step biosensing device using grapheme/AuNPs composite;B.Nagar et.al;《Biosens.Bioelectron 》;20181231;全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109765209A (en) | 2019-05-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Li et al. | Morphology-dependent MnO2/nitrogen-doped graphene nanocomposites for simultaneous detection of trace dopamine and uric acid | |
| Aziz et al. | Self-stacking of exfoliated charged nanosheets of LDHs and graphene as biosensor with real-time tracking of dopamine from live cells | |
| Shabnam et al. | Doped graphene/Cu nanocomposite: A high sensitivity non-enzymatic glucose sensor for food | |
| Joshi et al. | Mesoporous nitrogen containing carbon materials for the simultaneous detection of ascorbic acid, dopamine and uric acid | |
| Nazari et al. | A novel fabrication of sensor using ZnO-Al2O3 ceramic nanofibers to simultaneously detect catechol and hydroquinone | |
| Kokulnathan et al. | Trace level electrochemical determination of the neurotransmitter dopamine in biological samples based on iron oxide nanoparticle decorated graphene sheets | |
| Dong et al. | Three-dimensional Cu foam-supported single crystalline mesoporous Cu2O nanothorn arrays for ultra-highly sensitive and efficient nonenzymatic detection of glucose | |
| Mahmoud et al. | Self-assembly of porous copper oxide hierarchical nanostructures for selective determinations of glucose and ascorbic acid | |
| Yuan et al. | Highly ordered platinum‐nanotubule arrays for amperometric glucose sensing | |
| CN109765209B (en) | Preparation method and application of bifunctional expanded graphite/nanogold composite electrode | |
| Zhu et al. | Disposable and portable gold nanoparticles modified-laser-scribed graphene sensing strips for electrochemical, non-enzymatic detection of glucose | |
| Numan et al. | Binary nanocomposite based on Co 3 O 4 nanocubes and multiwalled carbon nanotubes as an ultrasensitive platform for amperometric determination of dopamine | |
| He et al. | A highly sensitive sensor for simultaneous determination of ascorbic acid, dopamine and uric acid based on ultra-small Ni nanoparticles | |
| Ko et al. | A high performance non-enzymatic glucose sensor based on nickel hydroxide modified nitrogen-incorporated nanodiamonds | |
| Rezaei et al. | Electrodeposited silver nanodendrites electrode with strongly enhanced electrocatalytic activity | |
| Wang et al. | PtAu alloy nanoflowers on 3D porous ionic liquid functionalized graphene-wrapped activated carbon fiber as a flexible microelectrode for near-cell detection of cancer | |
| Tong et al. | Electrochemical determination of dopamine based on electrospun CeO2/Au composite nanofibers | |
| Huang et al. | A sequence-specific DNA electrochemical sensor based on acetylene black incorporated two-dimensional CuS nanosheets and gold nanoparticles | |
| Chen et al. | Preparation of Ni (OH) 2 nanoplatelet/electrospun carbon nanofiber hybrids for highly sensitive nonenzymatic glucose sensors | |
| CN103789807B (en) | The nano-tube array that noble metal nano structural unit is constructed and preparation method and the application in organic molecule detects thereof | |
| Tsai et al. | Selective detection of dopamine in urine with electrodes modified by gold nanodendrite and anionic self-assembled monolayer | |
| Sookhakian et al. | Layer-by-layer electrodeposited nanowall-like palladium-reduced graphene oxide film as a highly-sensitive electrochemical non-enzymatic sensor | |
| Wang et al. | Mesoporous CuO: Alternative enzyme-free glucose sensing structure with excellent kinetics of electrode process | |
| Purohit et al. | Electrodeposition of metallic nanostructures for biosensing applications in health care | |
| Singh et al. | Palladium nanoparticles decorated electrostatically functionalized MWCNTs as a non enzymatic glucose sensor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |