CN113533450A - Sensitive electrode, formaldehyde flexible sensor and preparation method thereof - Google Patents
Sensitive electrode, formaldehyde flexible sensor and preparation method thereof Download PDFInfo
- Publication number
- CN113533450A CN113533450A CN202110783869.8A CN202110783869A CN113533450A CN 113533450 A CN113533450 A CN 113533450A CN 202110783869 A CN202110783869 A CN 202110783869A CN 113533450 A CN113533450 A CN 113533450A
- Authority
- CN
- China
- Prior art keywords
- tio
- sensitive electrode
- coag
- nanotube
- titanium foil
- 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.)
- Granted
Links
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 title claims abstract description 132
- 238000002360 preparation method Methods 0.000 title claims abstract description 12
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims abstract description 46
- 239000002071 nanotube Substances 0.000 claims abstract description 45
- 238000006243 chemical reaction Methods 0.000 claims abstract description 24
- 239000004205 dimethyl polysiloxane Substances 0.000 claims abstract description 16
- 229920000435 poly(dimethylsiloxane) Polymers 0.000 claims abstract description 16
- 239000003054 catalyst Substances 0.000 claims abstract description 15
- 238000004528 spin coating Methods 0.000 claims abstract description 14
- 238000009792 diffusion process Methods 0.000 claims abstract description 11
- 239000012528 membrane Substances 0.000 claims abstract description 8
- 229920000557 Nafion® Polymers 0.000 claims abstract description 7
- 239000000956 alloy Substances 0.000 claims abstract description 7
- 239000011248 coating agent Substances 0.000 claims abstract description 7
- 238000000576 coating method Methods 0.000 claims abstract description 7
- 229910045601 alloy Inorganic materials 0.000 claims abstract description 5
- 235000013870 dimethyl polysiloxane Nutrition 0.000 claims abstract 5
- CXQXSVUQTKDNFP-UHFFFAOYSA-N octamethyltrisiloxane Chemical compound C[Si](C)(C)O[Si](C)(C)O[Si](C)(C)C CXQXSVUQTKDNFP-UHFFFAOYSA-N 0.000 claims abstract 5
- 238000004987 plasma desorption mass spectroscopy Methods 0.000 claims abstract 5
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N titanium dioxide Inorganic materials O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims description 25
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 claims description 23
- PAYRUJLWNCNPSJ-UHFFFAOYSA-N Aniline Chemical compound NC1=CC=CC=C1 PAYRUJLWNCNPSJ-UHFFFAOYSA-N 0.000 claims description 18
- 239000000243 solution Substances 0.000 claims description 16
- 238000009713 electroplating Methods 0.000 claims description 14
- ROOXNKNUYICQNP-UHFFFAOYSA-N ammonium persulfate Chemical compound [NH4+].[NH4+].[O-]S(=O)(=O)OOS([O-])(=O)=O ROOXNKNUYICQNP-UHFFFAOYSA-N 0.000 claims description 10
- 239000011148 porous material Substances 0.000 claims description 10
- 238000001914 filtration Methods 0.000 claims description 8
- 238000000034 method Methods 0.000 claims description 8
- 238000003756 stirring Methods 0.000 claims description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 8
- 238000005406 washing Methods 0.000 claims description 7
- 239000003792 electrolyte Substances 0.000 claims description 6
- 238000003466 welding Methods 0.000 claims description 6
- GEYOCULIXLDCMW-UHFFFAOYSA-N 1,2-phenylenediamine Chemical compound NC1=CC=CC=C1N GEYOCULIXLDCMW-UHFFFAOYSA-N 0.000 claims description 5
- DZSVIVLGBJKQAP-UHFFFAOYSA-N 1-(2-methyl-5-propan-2-ylcyclohex-2-en-1-yl)propan-1-one Chemical compound CCC(=O)C1CC(C(C)C)CC=C1C DZSVIVLGBJKQAP-UHFFFAOYSA-N 0.000 claims description 5
- 229960001413 acetanilide Drugs 0.000 claims description 5
- 229910001870 ammonium persulfate Inorganic materials 0.000 claims description 5
- 238000001035 drying Methods 0.000 claims description 5
- 239000007788 liquid Substances 0.000 claims description 5
- 239000010936 titanium Substances 0.000 claims description 5
- 229910052719 titanium Inorganic materials 0.000 claims description 5
- 239000002131 composite material Substances 0.000 claims description 4
- 238000007789 sealing Methods 0.000 claims description 4
- SQGYOTSLMSWVJD-UHFFFAOYSA-N silver(I) nitrate Inorganic materials [Ag+].[O-]N(=O)=O SQGYOTSLMSWVJD-UHFFFAOYSA-N 0.000 claims description 4
- 239000003431 cross linking reagent Substances 0.000 claims description 3
- 239000000706 filtrate Substances 0.000 claims description 3
- 239000000047 product Substances 0.000 claims description 3
- 238000001291 vacuum drying Methods 0.000 claims description 3
- KGBXLFKZBHKPEV-UHFFFAOYSA-N boric acid Chemical compound OB(O)O KGBXLFKZBHKPEV-UHFFFAOYSA-N 0.000 claims description 2
- 239000011888 foil Substances 0.000 claims description 2
- 239000011259 mixed solution Substances 0.000 claims description 2
- 238000002156 mixing Methods 0.000 claims description 2
- 238000001132 ultrasonic dispersion Methods 0.000 claims description 2
- 238000001514 detection method Methods 0.000 abstract description 4
- 238000009987 spinning Methods 0.000 abstract description 2
- 238000000151 deposition Methods 0.000 abstract 1
- 239000007789 gas Substances 0.000 description 27
- 239000000463 material Substances 0.000 description 6
- 210000004379 membrane Anatomy 0.000 description 6
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 4
- 230000003197 catalytic effect Effects 0.000 description 4
- 239000007850 fluorescent dye Substances 0.000 description 4
- 229920000642 polymer Polymers 0.000 description 4
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 230000036541 health Effects 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 230000003647 oxidation Effects 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 230000035945 sensitivity Effects 0.000 description 3
- 239000010935 stainless steel Substances 0.000 description 3
- 229910001220 stainless steel Inorganic materials 0.000 description 3
- 239000000758 substrate Substances 0.000 description 3
- 229920000536 2-Acrylamido-2-methylpropane sulfonic acid Polymers 0.000 description 2
- XHZPRMZZQOIPDS-UHFFFAOYSA-N 2-Methyl-2-[(1-oxo-2-propenyl)amino]-1-propanesulfonic acid Chemical compound OS(=O)(=O)CC(C)(C)NC(=O)C=C XHZPRMZZQOIPDS-UHFFFAOYSA-N 0.000 description 2
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000007084 catalytic combustion reaction Methods 0.000 description 2
- 238000004587 chromatography analysis Methods 0.000 description 2
- 238000004140 cleaning Methods 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 239000012153 distilled water Substances 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- WSFSSNUMVMOOMR-NJFSPNSNSA-N methanone Chemical compound O=[14CH2] WSFSSNUMVMOOMR-NJFSPNSNSA-N 0.000 description 2
- 238000007747 plating Methods 0.000 description 2
- 231100000572 poisoning Toxicity 0.000 description 2
- 230000000607 poisoning effect Effects 0.000 description 2
- -1 polytetrafluoroethylene Polymers 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- 238000001179 sorption measurement Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 239000004753 textile Substances 0.000 description 2
- 238000012546 transfer Methods 0.000 description 2
- 206010028980 Neoplasm Diseases 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 201000011510 cancer Diseases 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000008367 deionised water Substances 0.000 description 1
- 229910021641 deionized water Inorganic materials 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000003487 electrochemical reaction Methods 0.000 description 1
- 230000005518 electrochemistry Effects 0.000 description 1
- 238000005868 electrolysis reaction Methods 0.000 description 1
- 235000019441 ethanol Nutrition 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 230000005661 hydrophobic surface Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000013067 intermediate product Substances 0.000 description 1
- 238000011068 loading method Methods 0.000 description 1
- 238000004020 luminiscence type Methods 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 210000004400 mucous membrane Anatomy 0.000 description 1
- 229910000510 noble metal Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000012466 permeate Substances 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 1
- 239000004810 polytetrafluoroethylene Substances 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000010791 quenching Methods 0.000 description 1
- 230000000171 quenching effect Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000036632 reaction speed Effects 0.000 description 1
- 210000002345 respiratory system Anatomy 0.000 description 1
- 239000000523 sample Substances 0.000 description 1
- 210000003491 skin Anatomy 0.000 description 1
- 150000003384 small molecules Chemical class 0.000 description 1
- 238000002791 soaking Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 230000000638 stimulation Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
- G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
- G01N27/12—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a solid body in dependence upon absorption of a fluid; of a solid body in dependence upon reaction with a fluid, for detecting components in the fluid
- G01N27/125—Composition of the body, e.g. the composition of its sensitive layer
- G01N27/126—Composition of the body, e.g. the composition of its sensitive layer comprising organic polymers
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
- G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
- G01N27/12—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a solid body in dependence upon absorption of a fluid; of a solid body in dependence upon reaction with a fluid, for detecting components in the fluid
- G01N27/125—Composition of the body, e.g. the composition of its sensitive layer
- G01N27/127—Composition of the body, e.g. the composition of its sensitive layer comprising nanoparticles
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
- G01N27/28—Electrolytic cell components
- G01N27/30—Electrodes, e.g. test electrodes; Half-cells
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
- Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Electrochemistry (AREA)
- Physics & Mathematics (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Nanotechnology (AREA)
- Engineering & Computer Science (AREA)
- Molecular Biology (AREA)
- Catalysts (AREA)
Abstract
The invention belongs to the technical field of gas sensors, and particularly relates to a sensitive electrode, a formaldehyde flexible sensor and a preparation method thereof. The preparation method of the sensitive electrode comprises the following steps: TiO 22Depositing a CoAg alloy on the nanotube/porous titanium foil, coating polyaniline-poly (2-acrylamide-2-methylpropanesulfonic acid), and then spin-coating PDMS on a single surface. The formaldehyde flexible sensor comprises a sensor shell, wherein an air chamber, a cathode diffusion layer, a cathode catalyst layer, a Nafion membrane, a sensitive electrode and a gas reaction chamber are sequentially arranged in the sensor shell, and one side of the sensitive electrode, which is coated with PDMS in a spinning mode, is close to the gas reaction chamber. The formaldehyde flexible sensor containing the sensitive electrode is safe and reliable when being applied to formaldehyde detection, environment-friendly, stable in performance, and high in anti-poisoning capacity and anti-interference capacity.
Description
Technical Field
The invention belongs to the technical field of gas sensors, and particularly relates to a sensitive electrode, a formaldehyde flexible sensor and a preparation method thereof.
Background
With the improvement of living standard and health consciousness of people, the indoor air quality problem becomes the focus of public attention. Among the many indoor harmful gases, formaldehyde is becoming the first killer harmful to human health. Formaldehyde is an important industrial raw material, is widely applied to the industrial fields of textile, coating, adhesive, wood processing and the like, becomes a main source of formaldehyde in air, and in addition, the mass use of various textiles and decorative materials also becomes a main source of formaldehyde. The formaldehyde is difficult to completely remove in a short time, can be slowly released in a long time, is harmful to the health of people, causes stimulation to the skin, mucous membrane and respiratory tract of the human body, and greatly increases the risk of cancer of people exposed to a high-concentration formaldehyde environment for a long time. Therefore, real-time concentration detection of indoor formaldehyde gas is particularly important.
The existing formaldehyde detection technology comprises a chemical method, a chromatography method, a fluorescence probe method, a sensor measurement method and the like. Among them, there are many chemical methods, but the same method is not suitable for formaldehyde of different concentrations, and the test time is long. The chromatography is costly. The organic small molecule fluorescent probe in the fluorescent probe method is very sensitive to environmental changes and can monitor the concentration of formaldehyde at any time, but most organic fluorescent molecules gather in a solid state to cause self fluorescence quenching, so that certain conditions are required for the use of the fluorescent probe, and the application of the solid-state fluorescent probe technology in actual detection is limited. The commonly used formaldehyde sensors mainly comprise electrochemistry, semiconductors, catalytic combustion, catalytic light emission, infrared rays and the like. Electrochemical, semiconductor and catalytic combustion sensors are simple in structure and convenient to operate, but signal stability and selectivity are affected by environmental factors. The infrared sensor has a complex structure and large power consumption. The catalytic luminescence sensor has high sensitivity, high reaction speed and strong stability, does not consume a catalyst in the reaction process, can monitor a plurality of gases such as formaldehyde and the like in the environment for a long time, but the catalyst needs to be loaded on a porous material, and the porosity after loading is obviously reduced.
Disclosure of Invention
In view of the above, in order to overcome the defects in the prior art, the present invention aims to provide a sensitive electrode, a formaldehyde flexible sensor and a preparation method thereof, wherein the flexible sensor has a good adsorption effect on formaldehyde, has high poisoning resistance and interference resistance, has stable performance, does not adopt noble metals, has low cost and zero power consumption, and is safe, reliable, environment-friendly, convenient to operate, simple and fast.
The invention provides a sensitive electrode for a formaldehyde flexible sensor, which is a polyaniline-poly (2-acrylamide-2-methylpropanesulfonic acid) coated CoAg-TiO2The nano tube/porous titanium foil is formed by spin coating PDMS on a single surface, wherein the CoAg-TiO is2The inner and outer surfaces of the pore of the nanotube/porous titanium foil are provided with CoAg-TiO2Porous titanium foil of nanotube, the CoAg-TiO2The sum of the contents of the CoAg alloys in the nanotubes is CoAg-TiO21-3 wt% of the nanotube.
The invention also provides a preparation method of the sensitive electrode, which comprises the following steps:
(1) carrying out electrolytic reaction on the porous titanium foil in electrolyte, taking out, washing, drying, roasting at 500-600 ℃ for 3 hours to form TiO on the inner and outer surfaces of the pores of the porous titanium foil2Nanotube to obtain TiO2Nanotube/porous titanium foil;
(2) subjecting the TiO to a reaction2The nanotube/porous titanium foil is used as a cathode and is placed in electroplating solution for electroplating at room temperature to obtain CoAg-TiO2Nanotube/porous titanium foil; the components of the electroplating solution are as follows: 0.01mol/L AgNO30.01mol/L of CoSO4And 20g/L of H3BO3(ii) a The pH of the electroplating solution is 4.4; the current density of the electroplating is 5mA/cm2The time is 30-90 min.
(3) Subjecting the CoAg-TiO to2Putting the nanotube/porous titanium foil into HCl solution, ultrasonically dispersing for 30min, adding aniline, o-phenylenediamine, 2-acrylamide-2-methylpropanesulfonic acid and p-acetanilide at 5 ℃, after vigorously stirring for 30min, dropping ammonium persulfate solution under stirring condition, and reacting for 6hRepeatedly washing the product with 0.1mol/L HCl solution until the filtrate is colorless, and vacuum drying at 60 ℃ for 8h to obtain polyaniline-poly (2-acrylamide-2-methylpropanesulfonic acid) coated CoAg-TiO2Nanotube/porous titanium foil composites; wherein the molar ratio of aniline to 2-acrylamide-2-methylpropanesulfonic acid is 2:1, and aniline and TiO2The molar ratio of the nanotubes is 3-1: 1;
(4) mixing and uniformly stirring PDMS prepolymer and cross-linking agent according to the mass ratio of 10:1 to obtain spin-coating liquid, and coating the polyaniline-poly (2-acrylamide-2-methylpropanesulfonic acid) with CoAg-TiO by using the spin-coating liquid2And spin-coating one surface of the nanotube/porous titanium foil composite material, and curing to obtain the sensitive electrode. 2. The sensing electrode according to claim 1, wherein the electrolyte is 0.5% -1% HF and 1mol/L H2SO4The mixed solution of (1); the electrolytic potential of the electrolytic reaction is 20V, and the time of the electrolytic reaction is 30-120 minutes.
Further, in the above preparation method, the spin coating specifically comprises: the rotation speed of 300r/min is continued for 10s, then the rotation speed of 2000r/min is continued for 30s, then the temperature is raised to 80 ℃, and the curing time is 60 min.
The invention also provides a formaldehyde flexible sensor with the sensitive electrode or the sensitive electrode prepared by the preparation method.
Furthermore, foretell flexible formaldehyde sensor, including the sensor housing, air chamber, cathode diffusion layer, cathode catalyst layer, Nafion membrane, sensitive electrode and gaseous reaction chamber have set gradually in the sensor housing, one side that sensitive electrode scribbled PDMS soon is close to gaseous reaction chamber, the cathode diffusion layer with the sensor housing connects through the welding point and sets up to the cathode output end, sensitive electrode with the sensor housing connects through the welding point and sets up to the anode output end, set up on the sensor housing with the air circulation hole that the air chamber switched on and with the gas filtration hole that gaseous reaction chamber switched on, be provided with the gas filtration cap on the gas filtration hole. The air circulation hole and the gas filtering hole are sealed by sealing covers, and the air chamber is provided withThe bottom of the sensitive electrode is provided with a water discharge hole, and the bottom of the sensitive electrode is provided with CO2A discharge orifice. The cathode output end is made of stainless steel, copper or titanium materials, and the anode output end is made of stainless steel, copper or titanium materials; the gas filtering cap is made of stainless steel or titanium; the sealing cover materials of the gas reaction chamber and the air circulation hole adopt polytetrafluoroethylene.
Compared with the prior art, the invention has the following beneficial effects:
1) in the sensitive electrode, the PDMS membrane with a porous structure has a good adsorption effect on formaldehyde, particularly low-concentration formaldehyde can play a good pre-enrichment effect, and the adsorbed formaldehyde can well permeate in PDMS and transfer to polyaniline-poly (2-acrylamide-2-methylpropanesulfonic acid) @ CoAg-TiO2Surface diffusion of nanotube catalyst, TiO2The specific surface area of the nano tube/porous titanium foil is high, and the CoAg alloy deposited on the surface of the nano tube/porous titanium foil can regulate and control and greatly reduce TiO2While being able to extract TiO2The conductivity of the nanotube is improved, the catalytic performance of the nanotube is improved, and meanwhile, the CoAg/TiO can be further improved by coating the surface with the high-conductivity porous spongy polymer polyaniline-poly (2-acrylamide-2-methylpropanesulfonic acid)2The electron conductivity and catalytic activity of the nanotubes, which act synergistically to enhance TiO2Catalytic oxidation performance to formaldehyde. Meanwhile, CO and other intermediate products generated by formaldehyde oxidation are easy to adsorb and transfer to CoAg-TiO2The nanotube surface is deeply oxidized into CO as a final product2Can improve the nano TiO2The composite catalyst has the capability of resisting CO poisoning, so that the cost of the catalyst in the sensitive electrode can be greatly reduced.
2) Polyaniline-poly (2-acrylamide-2 methylpropanesulfonic acid) @ CoAg-TiO in sensitive electrode2The nanotube catalyst is not consumed, the sensor can work at normal temperature when in use, has zero power consumption, can be used in various complex places, saves space, and is convenient, simple and rapid to operate.
Drawings
The invention is further illustrated by the following figures and examples.
FIG. 1 is a schematic structural diagram of a formaldehyde flexible sensor provided by the invention;
reference numerals: 1. a sensor housing; 2. an air chamber; 3. a cathode diffusion layer; 4. a cathode catalyst layer; 5. a Nafion membrane; 6. a sensitive electrode; 7. a cathode output end; 8. a gas reaction chamber; 9. an anode output end; 10. CO 22A discharge hole 11, a water discharge hole; 12. a gas filtering hole; 13. an air circulation hole;
fig. 2 is a zero point and sensitivity characteristic curve of formaldehyde flexible sensors (marked as a1, B1 and C1) using the sensitive electrodes prepared in example 1, example 2 and example 3 to formaldehyde.
Detailed Description
For a further understanding of the invention, reference will now be made to the preferred embodiments of the present invention by way of example, and it is to be understood that the description is intended to further illustrate features and advantages of the present invention and is not intended to limit the scope of the claims which follow.
All of the starting materials of the present invention, without particular limitation as to their source, may be purchased commercially or prepared according to conventional methods well known to those skilled in the art.
As shown in fig. 1, the invention provides a formaldehyde flexible sensor, which comprises a sensor housing 1, wherein an air chamber 2, a cathode diffusion layer 3, a cathode catalyst layer 4, a Nafion membrane 5, a sensitive electrode 6 and a gas reaction chamber 8 are sequentially arranged in the sensor housing 1, one side of the sensitive electrode 6, which is coated with PDMS in a spinning mode, is close to the gas reaction chamber 8, the cathode diffusion layer 3 is connected with the sensor housing 1 through a welding point to be set as a cathode output end 7, the sensitive electrode 6 is connected with the sensor housing 1 through a welding point to be set as an anode output end 9, an air flow hole 13 communicated with the air chamber 2 and a gas filter hole 12 communicated with the gas reaction chamber 8 are formed in the sensor housing 1, a gas filter cap is arranged on the gas filter hole 12, and the air flow hole 13 and the gas filter hole 12 are sealed by using a sealing cover, the bottom of the air chamber 2 is provided with a water discharge hole 11, and the bottom of the sensitive electrode 6 is provided with CO2A discharge orifice 10.
Polydimethylsiloxane (PDMS) is a stable elastic polymer with high hydrophobic surface, low density and strong biocompatibilityThe compound material has a porous structure, is beneficial to the permeation and diffusion of gas molecules in the material, and can play a good role in pre-enrichment of low-concentration gas. The working mechanism of the formaldehyde sensor is as follows: formaldehyde with the concentration to be measured enters the gas reaction chamber through diffusion holes on the gas filter cap and reacts with polyaniline-poly (2-acrylamide-2-methylpropanesulfonic acid) @ CoAg-TiO on the surface of the sensitive electrode (6)2The nanotube catalyst reacts (the sensitive electrode is essentially the anode of the electrochemical reaction), and the formaldehyde gas is oxidized into CO2While producing protons (H)+) And electron (e)-) The protons combine with oxygen and electrons in the air chamber at the surface of the cathode catalyst (3) through the Nafion membrane (5) to generate water (the air flow holes are opened during operation). During the reaction process, protons are transmitted through the Nafion membrane (5), and electrons are transmitted through an external circuit. The external current is related to the concentration of the formaldehyde gas, a standard curve is drawn by measuring the external circuit current of the standard formaldehyde concentration, and the formaldehyde concentration in the gas environment to be measured can be measured by measuring the external circuit current of the formaldehyde concentration to be measured.
In order to further illustrate the present invention, the preparation of the sensing electrode (6) of the present invention is described in detail below with reference to examples.
Example 1
(1) Pretreatment of the titanium foil: ultrasonically removing oil in acetone for 15 minutes, cleaning with methanol or ethanol, treating with 1mol/L HF for 10 minutes, ultrasonically cleaning with secondary distilled water for 3 times, and drying;
(2) forming a porous titanium foil: soaking the cleaned titanium foil in H2O2Heating to 90 ℃ in the medium, continuing heating for 40-60 min until H2O2And (3) taking out the titanium foil after the titanium foil is slightly dark blue, washing the titanium foil for a plurality of times by using distilled water and absolute ethyl alcohol, drying the titanium foil, calcining the titanium foil in a muffle furnace at 300 ℃ for 30min, and taking out the titanium foil to obtain the titanium foil with the three-dimensional porous structure.
(3) TiO on inner and outer surfaces of pores2And (3) forming the nanotubes: carrying out anodic oxidation on the treated porous titanium foil in electrolyte; composition of the electrolyte: 0.5% -1% of HF, 1mol/L of H2SO4The electrolytic potential is 20V, and the electrolytic time is 30-120 minutes; after electrolysis, washing with deionized waterDrying, roasting in a muffle furnace at 500-600 ℃ for 3 hours to obtain TiO formed on the inner and outer surfaces of the pore2A nanotube;
(4) electroplating to deposit the nano CoAg alloy: forming TiO on the inner and outer surfaces of the prepared pores2Electroplating with porous titanium foil as cathode, wherein the electroplating solution comprises the following components in percentage by weight:
after the electroplating is finished, washing by deionized water, and drying to obtain the porous titanium foil as TiO on the inner and outer surfaces of the substrate pores2Nano TiO of nano tube loaded CoAg alloy2And (3) compounding a catalyst.
(5) Coating with polyaniline-poly (2-acrylamide-2-methylpropanesulfonic acid): porous titanium foil as TiO on the inner and outer surfaces of the substrate pore2Nano TiO of nano tube loaded CoAg alloy2Composite catalyst (in which CoAg-TiO2100mg of nano tube) is put into 150mL of 2mol/L HCl solution, ultrasonic dispersion is carried out for 30min, 232.5mg of aniline, 135mg of o-phenylenediamine, 1.035g of 2-acrylamide-2-methylpropanesulfonic acid and 84mg of p-acetanilide are added at the temperature of 5 ℃, after vigorous stirring is carried out for 30min, 50mL of 285mg of ammonium persulfate solution dissolved by 2mol/L of HCl is dripped under stirring to initiate polymerization reaction for 6h, the product is repeatedly washed by 0.1mol/L of HCl solution until the filtrate is colorless, vacuum drying is carried out for 8h at the temperature of 60 ℃, and the high-conductivity porous spongy polymer polyaniline-poly (2-acrylamide-2-methylpropanesulfonic acid) coated CoAg-TiO is prepared2Nanotube/porous titanium foil.
(6) CoAg-TiO coated with PDMS and polyaniline-poly (2-acrylamide-2-methylpropanesulfonic acid)2Preparing a nanotube/porous titanium foil sensitive electrode: firstly, PDMS prepolymer and cross-linking agent (Sylgard 184, Dow Corning, USA) are mixed according to the mass ratio of 10:1 and stirred uniformly to form spin-coating liquid. Coating porous spongy polymer polyaniline-poly (2-acrylamide-2-methylpropanesulfonic acid) with CoAg-TiO2Placing the nanotube/porous titanium foil on a spin coater substrate for spin coating, wherein the spin coating process is carried out at a rotation speed of 300r/min for 10s, at a rotation speed of 2000r/min for 30s, heating to 80 ℃, and curing for 60minObtaining the porous PDMS film coated with CoAg-TiO2The sensitive electrode of polyaniline-poly (2-acrylamide-2-methylpropanesulfonic acid) is coated by the nanotube/porous titanium foil.
Example 2
The plating time in step (4) was 60 minutes, and in step (5), 348mg of aniline, 202.5mg of o-phenylenediamine, 1.5525g of 2-acrylamido-2-methylpropanesulfonic acid and 126mg of p-acetanilide, and 427.5m g of ammonium persulfate dissolved in 2mol/L of HCl were used as in example 1.
Example 3
The plating time in step (4) was 90 minutes, and in step (5), 116.3mg of aniline, 67.5mg of o-phenylenediamine, 517.5mg of 2-acrylamido-2-methylpropanesulfonic acid and 42mg of p-acetanilide, 142.5mg of ammonium persulfate dissolved in 2mol/L HCl, and the remainder was the same as in example 1.
FIG. 2 shows the current values of formaldehyde flexible sensors of the sensitive electrodes prepared in examples 1, 2 and 3 when the concentrations of formaldehyde sampled were 0, 20ppm, 40ppm, 60ppm, 80ppm, 100ppm, 200ppm, 300ppm, 500ppm and 800ppm, respectively. As can be seen in fig. 2, the three sensors are substantially comparable in sensitivity with little difference in zero. The formaldehyde concentration can be determined by measuring the current at which the sensor operates when the actual gas is sampled.
While there have been shown and described what are at present considered the fundamental principles and essential features of the invention and its advantages, it will be apparent to those skilled in the art that the invention is not limited to the details of the foregoing exemplary embodiments, but is capable of other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (5)
1. The sensitive electrode for the formaldehyde flexible sensor is characterized by being coated with CoAg-TiO (polyaniline-poly (2-acrylamide-2 methylpropanesulfonic acid)) by polyaniline-poly (2-acrylamide-2 methylpropanesulfonic acid)2The nano tube/porous titanium foil is formed by spin coating PDMS on a single surface, wherein the CoAg-TiO is2The inner and outer surfaces of the pore of the nanotube/porous titanium foil are provided with CoAg-TiO2Porous titanium foil of nanotube, the CoAg-TiO2The sum of the contents of the CoAg alloys in the nanotubes is CoAg-TiO21-3 wt% of the nanotube.
2. A method for preparing the sensitive electrode according to claim 1, comprising the steps of:
(1) carrying out electrolytic reaction on the porous titanium foil in electrolyte, taking out, washing, drying, roasting at 500-600 ℃ for 3 hours to form TiO on the inner and outer surfaces of the pores of the porous titanium foil2Nanotube to obtain TiO2Nanotube/porous titanium foil;
(2) subjecting the TiO to a reaction2The nanotube/porous titanium foil is used as a cathode and is placed in electroplating solution for electroplating at room temperature to obtain CoAg-TiO2Nanotube/porous titanium foil; the components of the electroplating solution are as follows: 0.01mol/L AgNO30.01mol/L of CoSO4And 20g/L of H3BO3(ii) a The pH of the electroplating solution is 4.4; the current density of the electroplating is 5mA/cm2The time is 30-90 min.
(3) Subjecting the CoAg-TiO to2Putting the nanotube/porous titanium foil into HCl solution, performing ultrasonic dispersion for 30min, adding aniline, o-phenylenediamine, 2-acrylamide-2-methylpropanesulfonic acid and p-acetanilide at 5 ℃, after vigorously stirring for 30min, dropping ammonium persulfate solution under stirring, reacting for 6h, repeatedly washing the product with 0.1mol/L HCl solution until the filtrate is colorless, and performing vacuum drying at 60 ℃ for 8h to obtain polyaniline-poly (2-acrylamide-2-methylpropanesulfonic acid) coated CoAg-TiO2Nanotube/porous titanium foil composites; wherein the molar ratio of aniline to 2-acrylamide-2-methylpropanesulfonic acid is 2:1, and aniline and TiO2The molar ratio of the nanotubes is3～1:1；
(4) Mixing and uniformly stirring PDMS prepolymer and cross-linking agent according to the mass ratio of 10:1 to obtain spin-coating liquid, and coating the polyaniline-poly (2-acrylamide-2-methylpropanesulfonic acid) with CoAg-TiO by using the spin-coating liquid2Spin coating one surface of the nanotube/porous titanium foil composite material, and curing to obtain a sensitive electrode;
the electrolyte is 0.5 to 1 percent of HF and 1mol/L of H2SO4The mixed solution of (1); the electrolytic potential of the electrolytic reaction is 20V, and the time of the electrolytic reaction is 30-120 minutes.
3. The preparation method according to claim 2, wherein the spin coating is specifically: the rotation speed of 300r/min is continued for 10s, then the rotation speed of 2000r/min is continued for 30s, then the temperature is raised to 80 ℃, and the curing time is 60 min.
4. A formaldehyde flexible sensor provided with the sensitive electrode as claimed in claim 1 or the sensitive electrode prepared by the preparation method as claimed in any one of claims 2 or 3.
5. The formaldehyde flexible sensor according to claim 4, characterized by comprising a sensor housing (1), wherein an air chamber (2), a cathode diffusion layer (3), a cathode catalyst layer (4), a Nafion membrane (5), a sensitive electrode (6) and a gas reaction chamber (8) are sequentially arranged in the sensor housing (1), one side of the sensitive electrode (6) coated with PDMS is close to the gas reaction chamber (8), the cathode diffusion layer (3) is connected with the sensor housing (1) through a welding point to form a cathode output end (7), the sensitive electrode (6) is connected with the sensor housing (1) through a welding point to form an anode output end (9), the sensor housing (1) is provided with an air circulation hole (13) communicated with the air chamber (2) and a gas filtering hole (12) communicated with the gas reaction chamber (8), the air circulation hole (13) and the gas filtering hole (12) are sealed by sealing covers, the bottom of the air chamber (2) is provided with a water discharge hole (11), and the bottom of the sensitive electrode (6) is provided with CO2A discharge orifice (10).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110783869.8A CN113533450B (en) | 2021-07-12 | 2021-07-12 | Sensitive electrode, formaldehyde flexible sensor and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110783869.8A CN113533450B (en) | 2021-07-12 | 2021-07-12 | Sensitive electrode, formaldehyde flexible sensor and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113533450A true CN113533450A (en) | 2021-10-22 |
| CN113533450B CN113533450B (en) | 2024-06-18 |
Family
ID=78098520
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110783869.8A Active CN113533450B (en) | 2021-07-12 | 2021-07-12 | Sensitive electrode, formaldehyde flexible sensor and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113533450B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104022295A (en) * | 2014-05-07 | 2014-09-03 | 南通大学 | Direct methanol fuel cell PdAg/TiO2 nanotube electrode and preparation method thereof |
| CN105277526A (en) * | 2015-10-09 | 2016-01-27 | 苏州大学 | Surface-enhanced Raman scattering substrate material, preparation method and application thereof |
| CN105932300A (en) * | 2016-05-30 | 2016-09-07 | 昆明纳太科技有限公司 | Gas diffusion electrode and preparation method thereof |
| CN107359356A (en) * | 2017-06-01 | 2017-11-17 | 南通大学 | A kind of anode catalysts for direct methanol fuel cell and preparation method |
| CN111141788A (en) * | 2019-12-31 | 2020-05-12 | 南通大学 | Black phosphorus-TiO2Nano tube/Ti sensitive electrode hydrogen sulfide sensor |
-
2021
- 2021-07-12 CN CN202110783869.8A patent/CN113533450B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104022295A (en) * | 2014-05-07 | 2014-09-03 | 南通大学 | Direct methanol fuel cell PdAg/TiO2 nanotube electrode and preparation method thereof |
| CN105277526A (en) * | 2015-10-09 | 2016-01-27 | 苏州大学 | Surface-enhanced Raman scattering substrate material, preparation method and application thereof |
| CN105932300A (en) * | 2016-05-30 | 2016-09-07 | 昆明纳太科技有限公司 | Gas diffusion electrode and preparation method thereof |
| CN107359356A (en) * | 2017-06-01 | 2017-11-17 | 南通大学 | A kind of anode catalysts for direct methanol fuel cell and preparation method |
| CN111141788A (en) * | 2019-12-31 | 2020-05-12 | 南通大学 | Black phosphorus-TiO2Nano tube/Ti sensitive electrode hydrogen sulfide sensor |
Non-Patent Citations (2)
| Title |
|---|
| ECE ALTUNBAS SAHIN: "Methanol electrooxidation activity of binary CoAg electrocatalyst", 《HYDROGEN ENERGY》, pages 35013 - 35022 * |
| 鞠一逸: "WO3-TiO2/C@Fe3O4纳米复合粉体的制备及对甲基橙的太阳光催化降解", 《南通大学学报》, 31 December 2017 (2017-12-31) * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113533450B (en) | 2024-06-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US9863047B2 (en) | Electrolysis device and refrigerator | |
| Cornejo et al. | Surface modification for enhanced biofilm formation and electron transport in shewanella anodes | |
| Li et al. | Nanoporous CuO layer modified Cu electrode for high performance enzymatic and non-enzymatic glucose sensing | |
| CN103046072B (en) | Mn/Nano-G|foam-Ni/Pd combination electrode and preparation method thereof | |
| CN103285891A (en) | Preparation method of bismuth oxide halide-titanium oxide nanotube array composite photo-catalytic membrane | |
| CN111551596A (en) | Preparation method of photoelectric chemical sensor for efficiently and sensitively detecting kanamycin | |
| CN113353932A (en) | Hierarchical pore charcoal electrocatalyst prepared from pitaya peel and preparation method and application thereof | |
| CN109828009A (en) | A kind of H based on metal oxide semiconductor films material2S gas sensor and preparation method thereof | |
| Kamyabi et al. | A highly sensitive ECL platform based on GOD and NiO nanoparticle decorated nickel foam for determination of glucose in serum samples | |
| Zhu et al. | A fuel-free self-powered sensor based on photoelectrochemical water/oxygen circulation for ultra-selective detection of levofloxacin | |
| CN113340954B (en) | Construction method of photo-assisted bipolar self-powered aptamer sensor for detecting lincomycin | |
| CN111003760A (en) | Preparation method of photoelectrocatalysis anode material with TNTs as substrate | |
| CN113533450B (en) | Sensitive electrode, formaldehyde flexible sensor and preparation method thereof | |
| CN103936107A (en) | 2-ethylanthraquinone/activated carbon-expanded graphite composite electrode, and preparation method and application thereof | |
| Arham et al. | Synthesis of TiO2 photoelectrode nanostructures for sensing and removing textile compounds rhodamine B | |
| Gholivand et al. | A nano-structured Ni (II)–chelidamic acid modified gold nanoparticle self-assembled electrode for electrocatalytic oxidation and determination of methanol | |
| CN110841664A (en) | Cu2O @ BiOI composite material and preparation method and application thereof | |
| CN111141788B (en) | Black phosphorus-TiO2Nano tube/Ti sensitive electrode hydrogen sulfide sensor | |
| CN114583183A (en) | Acidic glucose fuel cell electrode and preparation method thereof | |
| CN113337833B (en) | Polythiophene compound/carbon fiber cloth decomposed water oxygen generating electrode and preparation method thereof | |
| Razali et al. | Revolutionizing energy: tailored ZnOFe2O3/rGO for glucose oxidation in fuel cell application | |
| CN114778635A (en) | Glucose electrochemical sensor based on Ag @ ZIF-67 | |
| CN109873171B (en) | Composite electrode for microbial electrochemical system and preparation method thereof | |
| Anand et al. | Copper nanowires/reduced graphene oxide nanocomposite based non-enzymatic glucose sensor | |
| CN111215058A (en) | Silver surface modified mixed crystal type titanium dioxide nano net photo-electro-catalytic composite material |
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 |