CN106770485B - It is a kind of conduction kernel sensitive layer and molecular sieve remove wet layer sensor and preparation method - Google Patents
It is a kind of conduction kernel sensitive layer and molecular sieve remove wet layer sensor and preparation method Download PDFInfo
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- 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
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- B—PERFORMING OPERATIONS; TRANSPORTING
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- B01D2257/80—Water
Abstract
It is a kind of conduction kernel sensitive layer and molecular sieve remove wet layer exhalation sensor and preparation method, belong to material preparation and test and analyze technical field.The present invention uses the core-shell nano fiber with high conductivity kernel as the sensitive layer to interact with low concentration expiration marker, pass through the introducing of high conductivity kernel, amplify shell conductor oxidate resistance change rate, obtaining can be to the highly sensitive reliable detection of ppb concentration magnitude acetone gas.Further, Si hydrophobic molecular sieve filtration layer is modified on the basis of this sensitive layer, is maintained the local desiccation around device using the hydrophobic property of hydrophobic molecule sieve, is reduced interference of the high humidity environment to senser element, keep the miniaturization advantage of nano-device.It realizes to highly sensitive, the high moisture resistance of diabetes biomarker gas, low cost, non-invasive real-time detection in expiration.The type sensor can also be further used for the monitoring of other expiration markers.
Description
Technical field
The invention belongs to material preparation and test and analyze technical field, and in particular to a kind of conduction kernel sensitive layer and molecule
Screen out the sensor and preparation method of wet layer.
Background technique
Quick, accurate, simple and noninvasive detection prevention of disease is carried out to disease and detection has great importance.
Studies have shown that due in the Biochemical processes of human body different parts sick cell, can generate closely related a variety of therewith
Volatile organic compounds (VOCs), they can be external by alveolar exchange exhalation by blood circulation.For example, third in exhaling
Ketone gas is the metabolite of glucose in human body, can be used as the specific gas marker of diabetes diagnosis, usually health
The content of acetone is 0.3 ~ 0.9 ppm in individual exhaled gas, and the content of acetone is then higher than in diabetic's exhaled gas
1.8 ppm.So the concentration of VOCs changes in observation expiration, a directly monitoring human health situation is provided for researcher
Biological window.In addition, expression of the VOCs in expiration be usually prior to the appearance of clinical symptoms, quick diagnosis to disease nor
Chang Youli.The detection method for being applied to VOCs marker in exhaling at present is broadly divided into spectral line measuring method and Sensitive Detector
Part.Though spectral line measuring method using can also meet noninvasive requirement extensively, because volume is big, expensive, storage environment and technology
Level requirement is high, needs to limit its popularization and use to the disadvantages of under test gas preenrichment.In view of conventional needle to expiration marker
Number of drawbacks existing for detection method, designs that a kind of function admirable, low cost, quick, noninvasive vitro detection disease device is aobvious
It obtains extremely urgent.The appearance of sensing detection device is that exhaled gas detection Portable practical opens a frontier, especially
Resistive memory oxide (SMO) gas sensor is because having to low concentration VOCs high sensitivity, easy to operate, small in size etc.
Feature becomes by a kind of exhaled gas senser element of popular research.
In sensing detection device, have in the gas-sensitive sensor device based on conductor oxidate highly sensitive, quickly dynamic
The state response time, it is easy to operate and cheap the features such as, air pollution, personal health and in terms of have it is non-
Often high research and application value.Wherein, in terms of non-intrusion type quick diagnosis disease, conductor oxidate senser element is utilized
Micro marker also receives everybody extensive concern in detection expiration.But currently, still there are many bottles in actually detected
Neck problem needs to solve.Firstly, the gas marker in exhaling is all in ppb magnitude, and conductor oxidate gas sensor
For this concentration magnitude gas detection validity and reliability up for improve.In addition, human exhaled breath's environment is with high
Moisture composition, this to conductor oxidate senser element detection accuracy have very big interference.Although at present in some works
The mode of external dehumidifying gas circuit is taken to remove the moisture composition in exhaling in work, but such connection type undoubtedly makes semiconductor
Oxide sensor part loses the advantage of miniaturization, is unfavorable for the integrated of late device.
Summary of the invention
The purpose of the invention is to overcome the deficiencies of existing technologies, and provide a kind of nucleocapsid with high conductivity kernel
Nanofiber amplifies shell by the introducing of high conductivity kernel as the sensitive layer to interact with low concentration expiration marker
Layer conductor oxidate resistance change rate, obtaining can be to the highly sensitive reliable detection of ppb concentration magnitude acetone gas.Into one
Step modifies Si hydrophobic molecular sieve filtration layer on the basis of this sensitive layer, is maintained using the hydrophobic property of hydrophobic molecule sieve
Local desiccation around device reduces interference of the high humidity environment to senser element, keeps the miniaturization advantage of nano-device.It is real
Now to highly sensitive, the high moisture resistance of biomarker gas, low cost, non-invasive real-time detection in expiration.
It is a kind of conduction kernel sensitive layer and molecular sieve remove wet layer sensor, from top to bottom successively include have molecular sieve it is wet
Sensitive layer, electrode, substrate and the heater strip of gas filter layer, high conductivity kernel nanofiber；Wherein, the sensitive layer thickness
It is 100nm-1 μm, for molecular sieve moisture filter layer with a thickness of 1 μm -10 μm, the electrode is gold electrode, copper electrode or platinum electrode,
The material of substrate is ceramics, and the material of heater strip is nichrome；The material of the molecular sieve moisture filter layer be SBA-15 or
The kernel of MCM-41, the sensitive layer of the high conductivity kernel nanofiber are platinum, gold or palladium, and shell is conductor oxidate.
It is a kind of conduction kernel sensitive layer and molecular sieve except wet layer sensor preparation method:
(1) preparation of the core-shell nano fiber with high conductivity kernel:
The preparation of outer shell precursor solution: the inorganic salts containing conductor oxidate cation or organic salt are dissolved
In solvent, 5-30 min is stirred, the conductive polymer polymer of mass fraction 8-30% is added, and salt is kept to lead with macromolecule
The mass ratio of electric polymer in the solution is between 15-50%, and after uniformly mixing 0.5-12 h, it is molten to form outer shell precursor
Liquid；
The preparation of interior metal core precursor solution: metal inorganic salts (such as gold chlorides, chlorine platinum such as Au, Pt, Pd will be contained
Acid, palladium chloride etc.) it is dissolved in solvent, the conductive polymer polymer of mass fraction 8-30% is added after mixing, and keep
The mass ratio of metal inorganic salt and conductive polymer polymer in the solution is between 15-50%, after uniformly mixing 0.5-12 h,
Form interior metal core precursor solution；
Outer shell precursor solution obtained, interior metal core precursor solution are put into together according to molar ratio 1:5-20
Electrostatic spinning is carried out in axis electrostatic spinning apparatus, electrospinning fibre obtained carries out subsequent heat after being dried at room temperature for 6-12h
Processing is to obtain final core-shell nanostructure；Wherein, heat treatment process is with 1-10oThe heating rate of C/min is from room temperature
Rise to 450-800 o C, and it is down to room temperature naturally after keeping 2-5 h at this temperature；The main purpose of slow heating rate
It is slowly to remove organic moiety under the premise of keeping nanofiber original shape looks constant.
(2) prepared by the gas sensor with high conductivity kernel nanofiber sensitive layer
Core-shell nanostructure obtained above and adhesive are mixed and made into coating shape mixture, mixing mass ratio 10:
Then it is flat there are two the ceramic tube of discrete electrodes or with interdigital electrode to be uniformly applied to band by 1-15:1 for coating shape mixture
On plate ceramics, smearing thickness is 100nm-1 μm, and room temperature dries 12-24 h, in 250-550 o C handles 0.5-4 h, it is therefore an objective to
The organic solvent in mixture is removed, high conductivity kernel nanofiber sensitive layer gas-sensitive sensor device has been finally obtained.
(3) modification of molecular sieve moisture filter layer is carried out to gas-sensitive sensor device obtained:
Drag coating: if there are two the ceramic tubes of discrete electrodes using band when preparing sensitive layer, in molecular sieve moisture mistake
It is used when filtering layer is modified and drags coating；Molecular sieve is mixed with adhesive first, is ground 5-15 minutes, is made uniform sticky molten
Liquid, molecular sieve quality concentration are 15-25 %；Gas-sensitive sensor device prepared by step (2) is vertically arranged in above-mentioned viscous solution,
And with the speed of 0.05-0.2 cm/s by senser element vertical-lift, until all leave liquid level, drag painting with a thickness of 1 μm -10
μm, drying at room temperature 1-5 hours, with 1-10 min/oThe heating rate of C, is warming up to 200-500oC is kept for 1-3 hours；
Scraper method: if being filtered using the flat ceramic for having interdigital electrode in molecular sieve moisture when preparing sensitive layer
Scraper method is used when layer modification；Molecular sieve is put into mortar, be added mass fraction 0.1-1%=glacial acetic acid grind 1-3 minutes；Again
The deionized water that mass fraction 0.1-1% is added is ground 5-8 minutes, is repeated 5-10 times；The ethyl alcohol that 0.1-1% is added is ground 1 minute,
It repeats 5-10 times；3-5 times of volume ethanol of molecular sieve is added, so that molecular sieve powder is formed suspension and adds after 15-30 minutes ultrasonic
Enter the cellulose acetate of 3-8% mass ratio and the isopropanol of 0.3-0.8% mass ratio, is sufficiently stirred 30 minutes, in 55-85 o C adds
Heat, until forming the slurry of wire drawing shape；Flat ceramic with interdigital electrode is fixed, and 50-200 μ L slurry is placed in and is had
Slurry is uniformly firmly scraped to the other end with knife is hung, slurry is uniformly laid on electrode surface by flat ceramic one end of interdigital electrode,
Repeat 3-5 time, blade coating with a thickness of 1 μm -10 μm, the angle of scraper and horizontal plane is 15-45o, after 5-10 h dries, with 1-10
min/oThe heating rate of C, is warming up to 200-500oC is kept for 0.5-3 hours.
Further, the inorganic salts or organic salt as described in step (1) containing conductor oxidate cation, wherein
Conductor oxidate cation is In, Ti, Zn, Sn, W, Fe, Cu, Ni or Co；Inorganic salts or organic salt be nitrate, acetate,
Chloride or esters.
Further, conductive polymer polymer as described in step (1) can be the polyvinylpyrrolidine of different molecular weight
Ketone (PVP), polyacrylonitrile (PAN), polyvinyl alcohol (PVA), polymethyl methacrylate (PMMA) and polystyrene (PS) etc.,
In, different high molecular polymers should be selected in outer shell precursor solution, the preparation process of interior metal core presoma.This
It is because identical high molecular polymer is hardly formed continuous high conductivity kernel, it is therefore desirable to select different polyphosphazene polymers
Object is closed as presoma.
Further, electric spinning device described in step (1), wherein the size of syringe needle is 0.24- in coaxial spinneret
0.82 mm, the size of outer syringe needle are 1.27-1.59 mm；The distance between spinneret and collecting board are 5-35 cm, voltage value
For 5-30 kV, spinneret and horizontal angle are 15-90o, syringe pump fltting speed is 0.1-0.5 ml/h.
Further, solvent described in step (1) is the pure solution or mixed solution of DMF, ethyl alcohol or water.
Further, band described in step (2) is 1.0-2.0 cm there are two the length of the ceramic tube of discrete electrodes, outer straight
Diameter is 0.1-0.5 cm, and tube wall diameter is 200-300 μm, and both ends are equipped with Pt contact conductor；The plate with interdigital electrode
The length of ceramics is 1-3 cm, and width is 0.8-1.0 cm, and electrode zone is 3.5 *, 1.5 mm, inter-digital electrode width 3.5-
4.5 mm, interelectrode gap are 0.3-0.5 mm.
Further, adhesive described in step (2) and (3) is water, ethyl alcohol or abienol.
Further, molecular sieve described in step (3) is pure silicon, SBA-15 or MCM-41, avoids influence sensor quick
Feel layer increased resistance value, and shell electric conductivity is avoided preferably to form short circuit.
Compared with prior art, advantages of the present invention is as follows:
Sensor of the invention can accurately test object gas in the environment of high humility；It can be with tester
Body is really exhaled, and test result is mutually agreed with experimental result；The object gas of ppb magnitude can be tested and had very high sensitive
Degree；The addition of molecular sieve layer can remove extraneous dehumidification device and save cost；The design of high conductivity kernel can be more
The upper sensitivity for improving gas sensor.
Detailed description of the invention
Fig. 1: the coaxial electrostatic spinning schematic device of use；
In figure: syringe pump 1 at the uniform velocity promoting precursor solution, and enters in coaxial electrostatic spinning silk device；High-voltage electricity
Source 2, for providing high voltage, so that precursor solution generates the drawing force of moment at coaxial syringe needle；Coaxial syringe needle 3, is used for
Store precursor solution；Receiver board 4, nanofiber 5；
Fig. 2: for the expiration marker gas with high conductivity kernel nanofiber sensitive layer and molecular sieve moisture filter layer
Dependent sensor part structural schematic diagram；
In figure: nanofibrous structures film 6, molecular sieve layer 7, gold electrode 8, ceramic tube 9, heater strip 10；
Fig. 3: for Pt@In in embodiment 12O3The scanning transmission electron microscope figure of Coaxial Nanofibers；
In figure :(a) represent the scanning transmission electron microscope figure of coaxial core-shell structure, (b) represent the scanning transmission after 5 times of amplification
Electron microscope (c) represents the distribution diagram of element after coaxial core-shell structure is analyzed by Mapping, and sequence (from left to right) is respectively
It is the scanning transmission electron microscope figure in selection analysis region, oxygen element distribution, phosphide element distribution, platinum Elemental redistribution.
It can be with Pt In from figure (a)2O3Coaxial Nanofibers have the structure of the rule of overlength and uniform diameter, nucleocapsid knot
Structure is high-visible, and wherein the overall diameter of Coaxial Nanofibers is 80 nm, and interior nuclear diameter is 27 nm；It can see from figure (b)
Exterior I n2O3Shell layer surface has porous structure；It can prove that outer layer is In from figure (c)2O3, internal layer is Pt.
Fig. 4: for the SBA-15 molecular sieve structure schematic diagram used in embodiment 1 and embodiment 2；
It is the section SBA-15 photo from figure (a), it can be seen that the uniform cellular structure on surface；Scheming (b) is the side SBA-15
Photo, it can be seen that SBA-15 molecular sieve has overlength and top-down cellular structure, is conducive to passing through for object gas；
Fig. 5: in embodiment 1, only Pt@In2O3The device of Coaxial Nanofibers sensitive layer is based on Pd@In2O3Coaxially
The interdigitated transducers part of nanofiber sensitive layer and SBA-15 molecular sieve filtration layer, under different humidity environment, for 1.8 ppm
The change curve of acetone concentration response；
In figure :(a) represent and there was only Pt@In2O3The device of Coaxial Nanofibers sensitive layer under different humidity environment, for
The change curve of 1.8 ppm acetone concentrations response, (b) represents and is based on Pd@In2O3Coaxial Nanofibers sensitive layer and SBA-15 divide
Under the interdigitated transducers part different humidity environment of the sieved filtering layer of son, for the change curve of 1.8 ppm acetone concentrations response.
From Fig. 5 (a) as can be seen that in the case where the protection of no SBA-15 molecular sieve filtration layer, with ambient humidity
It improves, only Pt@In2O3The device of Coaxial Nanofibers sensitive layer to 1.8 ppm acetone concentrations respond constantly reduce, this be by
Pt@In is occupied in high concentration moisture2O3Coaxial Nanofibers sensitivity layer surface makes it for the effective area drop of acetone response
It is low；It is being based on Pt@In2O3(Fig. 5 in the interdigitated transducers part of Coaxial Nanofibers sensitive layer and SBA-15 molecular sieve filtration layer
(b)), due to the protection and filtration of SBA-15 molecular sieve filtration layer, device is basic for 1.8 ppm acetone concentration responses
Do not change with the increase of ambient humidity；Wherein S1 represents pure indium oxide nanometer fiber gas sensor, S2 represent indium oxide/
The gas sensor of platinum (atomic ratio=10/1) mixing and doping, S3 represent the Pt@In of internal discontinuous platinum core2O3(atomic ratio In/Pt
=20/1) Coaxial Nanofibers gas sensor, S4 represent the Pt@In of internal continuous high conductivity kernel2O3(atomic ratio In/
Pt=10/1) Coaxial Nanofibers gas sensor, S5 represents the Pt@In of internal continuous high conductivity kernel2O3(atomic ratio
In/Pt=5/1) Coaxial Nanofibers gas sensor.
Fig. 6: Pd@In is based on for embodiment 2 is obtained2O3: Yb Coaxial Nanofibers sensitive layer and SBA-15 molecule are sieved through
The interdigitated transducers part of filtering layer, places it in the response in the specimen of breath and diabetic's specimen of breath of healthy control group
Value；
It can be seen from the figure that senser element is apparently higher than to healthy control group the response of diabetes specimen of breath
The response of specimen of breath；
Fig. 7: it is obtained under 90 RH% humidity environments for embodiment 3, it is based on Pt@(ZnO-CuO) Coaxial Nanofibers
The ceramic tube senser element of sensitive layer and SBA-15 molecular sieve filtration layer, for healthy threshold value (1.8 ppm) nearby difference third
The dynamic response curve of ketone concentration；
It can be seen from the figure that although gas sensor is still with third in acetone/air Mixture under high humidity environment
The increase of ketone concentration, response are continuously increased, and when removing acetone/air Mixture, response is restored to original shape
State.
Specific embodiment
With reference to the accompanying drawing and example the invention will be further described:
Embodiment 1: it is based on Pt@In2O3The ceramic tube of Coaxial Nanofibers sensitive layer and SBA-15 molecular sieve filtration layer sensing
The preparation method of device
(1) with the Pt@In of Pt high conductivity kernel2O3The preparation of core-shell nano fiber
The preparation of outer shell precursor solution: by 0.72gIn (NO3)3.4.5H2O is dissolved in the mixed of 10mLDMF and ethyl alcohol
It closes in solution (volume ratio of DMF and ethyl alcohol be 4:1), stirs 20 min, the PVP of 2 g is added after mixing, and (molecular weight is
130000), after 6 h of magnetic agitation, sticky outer shell precursor solution is formed；
The preparation of interior metal core precursor solution: by 100 μ L H2PtCl6It is dissolved in 10 mL DMF solutions, stirring 1
The PAN (molecular weight 150000) of 1 g is added in h after mixing, and In/Pt molar ratio is 10 at this time.After 6 h of magnetic agitation,
Form sticky interior metal core precursor solution；
The outer shell precursor solution of acquisition, interior metal core precursor solution are put into coaxial electrostatic spinning silk device
In, the size of syringe needle is 0.34 mm in coaxial spinneret, and the size of outer syringe needle is 1.47 mm.Electrospinning condition: spinneret and receipts
Collecting the distance between plate is 15 cm, and voltage value is 15 kV, and spinneret and horizontal angle are 90o, electro-spinning process is indoors
It is carried out under environment, electrospinning fibre obtained is dried at room temperature for 12 h.The electrospinning precursor fibre of acquisition is placed in program control
In warm furnace, with 1oThe heating rate of C/min rises to 500 from room temperature oC, and it is down to room naturally after keeping 3 h at this temperature
Temperature.The Pt@In finally obtained2O3Coaxial Nanofibers are as shown in Fig. 3, Pt@In2O3Coaxial Nanofibers have overlength and straight
The structure of the uniform rule of diameter, core-shell structure is high-visible, and wherein the overall diameter of Coaxial Nanofibers is 80 nm, interior nuclear diameter
For 27 nm, and exterior I n2O3Shell layer surface has porous structure.
(2) there is Pt@In2O3It is prepared by the gas sensor of the sensitive layer of Coaxial Nanofibers
By Pt@In2O3Coaxial Nanofibers and ethyl alcohol are that 10:1 is mixed and made into coating shape mixture with mass ratio, using super
Fine, soft fur pen is uniformly applied to band there are two on the ceramic tube of discrete electrodes, and smearing thickness is 1 μm, and the length of ceramic tube is 1.2
Cm, overall diameter are 0.3 cm, and tube wall diameter is 300 μm, and both ends are equipped with Pt contact conductor, and room temperature dries 12 h, is placed in high temperature furnace
In 350o C handles 3 h and is finally obtained with removing remaining alcohol solvent in electrode material with Pt@In2O3Co-axial nano is fine
Tie up the gas-sensitive sensor device of sensitive layer.
(3) modification of SBA-15 molecular sieve moisture filter layer is carried out to gas-sensitive sensor device obtained
Using ceramic pipe electrode when due to preparing sensitive layer, is then used in the modification of molecular sieve moisture filter layer and drag painting
Method.60 mg SBA-15 molecular sieves are mixed with 1 mL ethyl alcohol first, 10 min is ground, uniform viscous solution is made.By Pt@
In2O3The gas-sensitive sensor device of Coaxial Nanofibers sensitive layer is totally immersed into the viscous solution, and with 0.1 cms-1Speed
Slowly by senser element vertical-lift, until all leaving liquid level.3 h of drying at room temperature, is placed in temperature programmed control furnace, with 10
min/oThe heating rate of C, is warming up to 200oC keeps 1 h.Drag painting with a thickness of 1 μm.
(4) the made gas sensing electrode of step (3) is placed among sealing container, connects gas test instrument with conducting wire.
Then to the acetone for injecting various concentration in the closed container, it is followed successively by 0 ppm of concentration, 0.2 ppm, 0.5 ppm, 1ppm, 5
Ppm, 10 ppm, 20 ppm, the acetone of 50 ppm and air gaseous mixture, using the bright Sheng WS-30A gas test instrument in Zhengzhou,
Measure the resistance change of gas sensor in object gas and in air environment.With the resistance value and absorption acetone gas in air
The ratio of device resistance value is that ordinate is fitted using acetone concentration in gaseous mixture as abscissa after body, obtains concentration relationship
Curve.In test scope, device shows good linear relationship, explanation between response and gas concentration variation
Pt@In2O3Coaxial Nanofibers sensitive layer has good acetone air-sensitive response characteristic.
(5) device obtained is placed in different humidity environments (25-95 RH%), and injects the acetone of 1.8 ppm
Gas, observation introduce after external SBA-15 molecular sieve filtration layer, noiseproof feature of the device for outer moisture environment.It is such as attached
Shown in Fig. 5, only independent Pt@In2O3The device of Coaxial Nanofibers sensitive layer is larger by the interference of humidity, sets when by device
When in acetone gas, since the aqueous vapor molecule of high concentration occupies the sensitive most effective coverage of layer surface, sensitive layer without
Method effectively interacts with target acetone gas；After introducing SBA-15 molecular sieve filtration layer, due to SBA-15 molecular sieve
Filter layer aqueous vapor molecule neighbouring during can effectively adsorbing, device still can carry out acetone gas under high moisture concentration
Effecting reaction is carried out with the gas under low-humidity environment.
Embodiment 2: it is based on Pd@In2O3: the interdigital biography of Yb Coaxial Nanofibers sensitive layer and SBA-15 molecular sieve filtration layer
The preparation and experiment of inductor component
(1) with the Pd@In of Pd high conductivity kernel2O3: the preparation of Yb core-shell nano fiber
The preparation of outer shell precursor solution: by 0.72g In (NO3)3.4.5H2Yb (the NO of O and 0.033g3)3Dissolution
In the mixed solution (volume ratio of DMF and ethyl alcohol is 4:1) of 10 mL DMF and ethyl alcohol, stir 20 min, after mixing plus
Enter the PVP (molecular weight 130000) of 2 g, after 6 h of magnetic agitation, forms sticky outer shell precursor solution.
The preparation of interior metal core precursor solution: by 100 μ L PdCl2It is dissolved in 10 mL DMF solutions, stirring 1
The PAN (molecular weight 150000) of 1 g is added in h after mixing, and In/Pd molar ratio is 7:1 at this time.6 h of magnetic agitation
Afterwards, sticky interior metal core precursor solution is formed.
The outer shell precursor solution of acquisition, interior metal core precursor solution are put into coaxial electrostatic spinning silk device
In, the size of syringe needle is 0.34 mm in coaxial spinneret, and the size of outer syringe needle is 1.47 mm.Electrospinning condition: spinneret and receipts
Collecting the distance between plate is 15 cm, and voltage value is 18 kV, spinneret and horizontal line, electro-spinning process indoors under environment into
Row, electrospinning fibre obtained are dried at room temperature for 6 h.The electrospinning precursor fibre of acquisition is placed in temperature programmed control furnace, with 1oThe heating rate of C/min rises to 500 from room temperatureo C, and it is down to room temperature naturally after keeping 3 h at this temperature, finally obtain
Pd@In2O3: Yb core-shell nano fiber.
(2) there is Pd@In2O3: the gas sensor preparation of the sensitive layer of Yb Coaxial Nanofibers
By Pd@In2O3: Yb Coaxial Nanofibers and ethyl alcohol are that 10:1 is mixed and made into coating shape mixture with mass ratio, are utilized
Ultra-fine writing brush is uniformly applied in interdigital plane electrode, and the substrate dimension of plane electrode is 1 cm, and substrate material is 0.8 cm, fork
Finger effective coverage is 3.5 mm*1.5 mm, and electrode spacing is 0.3 mm.Uniformly being applied to band using ultra-fine writing brush, there are two discrete
On the ceramic tube of electrode or the flat ceramic with interdigital electrode, room temperature dries 12 h, is placed in 350 in high temperature furnaceo C processing 3
H is finally obtained with removing remaining alcohol solvent in electrode material with Pd@In2O3: the gas of Yb Coaxial Nanofibers sensitive layer
Dependent sensor part.
(3) modification of SBA-15 molecular sieve moisture filter layer is carried out to gas-sensitive sensor device obtained
100 mg SBA-15 molecular sieves are put into mortar, the glacial acetic acid for being added 0.2% is ground 3 minutes；It is added 0.5 wt%'s
Deionized water grinds clock, is repeated 5 times；The ethyl alcohol that 0.5 wt% is added is ground 1 minute, is repeated 10 times.5 times of volume ethanols are added, make
Molecular sieve powder forms suspension, which is transferred in vial using syringe, and after twenty minutes, 5% matter is added in ultrasound
The cellulose acetate of ratio and 0.3% isopropanol are measured, is sufficiently stirred 30 minutes, is placed in 85 o On the heating platform of C, rotary heating
Until forming the slurry of wire drawing shape.Plane interdigital electrode is fixed with adhesive tape, and appropriate slurry is placed in the interdigital electricity of plane
Slurry is uniformly firmly scraped to the other end with knife is hung, slurry is uniformly laid on electrode surface, is repeated 3 times by pole one end, scraper and water
The angle of plane is 15o.After 10 h dry, electrode is placed in temperature programmed control furnace, with 10 min/oThe heating rate of C, is warming up to
500oC is kept for 1 hour.
(4) the made gas sensing electrode of step (3) is placed among sealing container, connects gas test instrument with conducting wire.
Then to the acetone for injecting various concentration in the closed container, it is followed successively by 0 ppm of concentration, 0.2 ppm, 0.5 ppm, 1ppm, 5
Ppm, 10 ppm, 20 ppm, the acetone of 50 ppm and air gaseous mixture, using the bright Sheng WS-30A gas test instrument in Zhengzhou,
Measure the resistance change of gas sensor in object gas and in air environment.With the resistance value and absorption acetone gas in air
The ratio of device resistance value is that ordinate is fitted using acetone concentration in gaseous mixture as abscissa after body, is determined in measurement model
Enclose interior available linear concentration relation curve.
(5) device obtained is placed in the specimen of breath and diabetic's specimen of breath of healthy control group, test is simultaneously
Device is observed for the response of different specimens of breath.Measurement result is as shown in Fig. 5, and as seen from the figure, senser element is to glycosuria
The response of sick specimen of breath is apparently higher than the response to the specimen of breath of healthy control group.
Embodiment 3: the ceramics based on Au@(ZnO-CuO) Coaxial Nanofibers sensitive layer and MCM-41 molecular sieve filtration layer
The preparation and experiment of tube sensor part
(1) preparation of Au@(ZnO-CuO) core-shell nano fiber with An high conductivity kernel
The preparation of outer shell precursor solution: 50 mL deionized waters are added in 100 mL three-necked bottles, and 5 g are added
Three-necked bottle is placed in 90 by PVA o Magnetic agitation and 3 h that flow back, it is water-soluble finally to obtain sticky and transparent PVA in C oil bath pan
Liquid.By 0.36g Zn (NO3)2.4.5H2O and 0.36g Cu (NO3)2.4.5H2O is dissolved in 5 mL aqueous solutions, stirs 20 min,
It is added 5 mL PVA aqueous solutions after mixing, after 3 h of magnetic agitation, forms sticky shell Electrospun precursor solution.
The preparation of interior metal core precursor solution: by 100 μ L H2AuCl6It is dissolved in 10 mL DMF solutions, stirring 1
The PVP (molecular weight 130000) of 1 g is added in h after mixing, and (Zn+Cu)/Au molar ratio is 8:1 at this time.Magnetic agitation 6
After h, sticky stratum nucleare Electrospun precursor solution is formed.
The inside and outside electrospinning precursor solution of acquisition is put into coaxial electrostatic spinning silk device, the ruler of syringe needle in coaxial spinneret
Very little is 0.34 mm, and the size of outer syringe needle is 1.47 mm.Electrospinning condition: the distance between spinneret and collecting board are 20 cm, electricity
Pressure value is 25 kV, spinneret and horizontal line, and electro-spinning process carries out under environment indoors, and electrospinning fibre obtained is in room
Lower dry 6 h of temperature.The electrospinning precursor fibre of acquisition is placed in temperature programmed control furnace, with 1oThe heating rate of C/min is from room
Temperature rise is to 450 o C, and it is down to room temperature naturally after keeping 4 h at this temperature, finally obtain Au@(ZnO-CuO) core-shell nano
Fiber.
(2) the gas sensor preparation of the sensitive layer with Au@(ZnO-CuO) Coaxial Nanofibers
Au@(ZnO-CuO) Coaxial Nanofibers and ethyl alcohol are mixed and made into coating shape mixture with mass ratio for 8:1, benefit
Band is uniformly applied to there are two on the ceramic tube of discrete electrodes with ultra-fine writing brush, and the length of ceramic tube is 1.2 cm, and overall diameter is
0.3 cm, tube wall diameter are 300 μm, and both ends are equipped with Pt contact conductor.Uniformly being applied to band using ultra-fine writing brush, there are two discrete
On the ceramic tube of electrode or the flat ceramic with interdigital electrode, room temperature dries 12 h, is placed in 350 in high temperature furnace o C processing 3
H is finally obtained with removing remaining alcohol solvent in electrode material with Au@(ZnO-CuO) Coaxial Nanofibers sensitive layer
Gas-sensitive sensor device.
(3) modification of MCM-41 molecular sieve moisture filter layer is carried out to gas-sensitive sensor device obtained
Using ceramic pipe electrode when due to preparing sensitive layer, is then used in the modification of molecular sieve moisture filter layer and drag painting
Method.80 mg MCM-41 molecular sieves are mixed with 1 mL ethyl alcohol first, 10 min is ground, uniform viscous solution is made.By Au@
(ZnO-CuO) gas-sensitive sensor device of Coaxial Nanofibers sensitive layer is totally immersed into the viscous solution, and with 0.1 cms-1's
Speed is slowly by senser element vertical-lift, until all leaving liquid level.3 h of drying at room temperature, is placed in temperature programmed control furnace, with 10
min/oThe heating rate of C, is warming up to 200oC keeps 1 h.
(4) the made gas sensing electrode of step (3) is placed among sealing container, connects gas test instrument with conducting wire.
Then to the acetone for injecting various concentration in the closed container, it is followed successively by 0 ppm of concentration, 0.2 ppm, 0.5 ppm, 1ppm, 5
Ppm, 10 ppm, 20 ppm, the acetone of 50 ppm and air gaseous mixture, using the bright Sheng WS-30A gas test instrument in Zhengzhou,
Measure the resistance change of gas sensor in object gas and in air environment.With the resistance value and absorption acetone gas in air
The ratio of device resistance value is that ordinate is fitted using acetone concentration in gaseous mixture as abscissa after body, obtains concentration relationship
Curve.In test scope, device with response and gas concentration variation between show good linear relationship, explanation
Au@(ZnO-CuO) Coaxial Nanofibers sensitive layer has good acetone air-sensitive response characteristic.
(5) device obtained is placed under 90 RH% humidity environments, measurement device under high humidity environment, for
The dynamic response curve of the neighbouring different acetone concentrations of healthy threshold value (1.8 ppm).Although from 7 figure of attached drawing it can be seen that in high humidity
It spends under environment, still with the increase of acetone concentration in acetone/air Mixture, response is continuously increased gas sensor, when
When removing acetone/air Mixture, response is restored to original state.
Claims (8)
1. the sensor that a kind of conduction kernel sensitive layer and molecular sieve remove wet layer, which is characterized in that from top to bottom successively include tool
There are sensitive layer, electrode, substrate and the heater strip of molecular sieve moisture filter layer, high conductivity kernel nanofiber；Wherein, described
Sensitive layer is with a thickness of 100nm-1 μm, and for molecular sieve moisture filter layer with a thickness of 1 μm -10 μm, the electrode is gold electrode, copper electricity
Pole or platinum electrode, the material of substrate are ceramics, and the material of heater strip is nichrome；The material of the molecular sieve moisture filter layer
For pure silicon, SBA-15 or MCM-41, the kernel of the sensitive layer of the high conductivity kernel nanofiber is platinum, gold or palladium, shell
For conductor oxidate.
2. the preparation method of the sensor of a kind of conductive kernel sensitive layer described in claim 1 and molecular sieve except wet layer, special
Sign is, the specific steps are as follows:
(1) preparation of the core-shell nano fiber with high conductivity kernel:
The preparation of outer shell precursor solution: the inorganic salts containing conductor oxidate cation or organic salt are dissolved in molten
In agent, 5-30 min is stirred, the conductive polymer polymer of mass fraction 8-30% is added, and keeps salt and conductive polymer poly-
The mass ratio of object in the solution is closed between 15-50%, after uniformly mixing 0.5-12 h, forms outer shell precursor solution；
The preparation of interior metal core precursor solution: it will be dissolved in solvent, be uniformly mixed containing Au, Pt or Pd metal inorganic salt
The conductive polymer polymer of mass fraction 8-30% is added afterwards, and keeps metal inorganic salt with conductive polymer polymer molten
Mass ratio in liquid is between 15-50%, after uniformly mixing 0.5-12 h, forms interior metal core precursor solution；
Outer shell precursor solution obtained, interior metal core precursor solution are put into according to molar ratio 1:5-20 coaxial quiet
Electrostatic spinning is carried out in electric spinning device, electrospinning fibre obtained carries out subsequent heat treatment after being dried at room temperature for 6-12h
To obtain final core-shell nanostructure；Wherein, heat treatment process is with 1-10oThe heating rate of C/min rises to from room temperature
450-800 o C, and it is down to room temperature naturally after keeping 2-5 h at this temperature；
(2) prepared by the gas sensor with high conductivity kernel nanofiber sensitive layer:
Core-shell nanostructure obtained above and adhesive are mixed and made into coating shape mixture, mixing mass ratio 10:1-15:
1, coating shape mixture is uniformly then applied to band there are two the ceramic tube of discrete electrodes or the plate with interdigital electrode is made pottery
On porcelain, smearing thickness is 100nm-1 μm, and room temperature dries 12-24 h, in 250-550 o C handles 0.5-4 h, it is therefore an objective to remove
Organic solvent in mixture has finally obtained high conductivity kernel nanofiber sensitive layer gas-sensitive sensor device；
(3) modification of molecular sieve moisture filter layer is carried out to gas-sensitive sensor device obtained:
Drag coating: if there are two the ceramic tubes of discrete electrodes using band when preparing sensitive layer, in molecular sieve moisture filter layer
It is used when modification and drags coating；Molecular sieve is mixed with adhesive first, grinds 5-15 minutes, uniform viscous solution is made, point
Son sieve mass concentration is 15-25 %；Gas-sensitive sensor device prepared by step (2) is vertically arranged in above-mentioned viscous solution, and with
The speed of 0.05-0.2 cm/s is by senser element vertical-lift, until all leave liquid level, drag painting with a thickness of 1 μm -10 μm,
Drying at room temperature 1-5 hours, with 1-10 min/oThe heating rate of C, is warming up to 200-500oC is kept for 1-3 hours；
Scraper method: if being repaired using the flat ceramic for having interdigital electrode in molecular sieve moisture filter layer when preparing sensitive layer
Scraper method is used when decorations；Molecular sieve is put into mortar, the glacial acetic acid that mass fraction 0.1-1% is added is ground 1-3 minutes；It adds
The deionized water of mass fraction 0.1-1% is ground 5-8 minutes, is repeated 5-10 times；The ethyl alcohol that 0.1-1% is added is ground 1 minute, is repeated
5-10 times；3-5 times of volume ethanol of molecular sieve is added, molecular sieve powder is made to form suspension, after 15-30 minutes ultrasonic, 3- is added
The cellulose acetate of 8% mass ratio and the isopropanol of 0.3-0.8% mass ratio, are sufficiently stirred 30 minutes, in 55-85 o C heating,
Until forming the slurry of wire drawing shape；Flat ceramic with interdigital electrode is fixed, and 50-200 μ L slurry is placed in fork
Slurry is uniformly firmly scraped to the other end with knife is hung, slurry is uniformly laid on electrode surface, weight by the flat ceramic one end for referring to electrode
Multiple 3-5 time, blade coating with a thickness of 1 μm -10 μm, the angle of scraper and horizontal plane is 15-45o, after 5-10 h dries, with 1-10
min/oThe heating rate of C, is warming up to 200-500oC is kept for 0.5-3 hours.
3. the preparation method of the sensor of a kind of conductive kernel sensitive layer as claimed in claim 2 and molecular sieve except wet layer,
It is characterized in that, the inorganic salts or organic salt as described in step (1) containing conductor oxidate cation, wherein semiconductor oxygen
Compound cation is In, Ti, Zn, Sn, W, Fe, Cu, Ni or Co；Inorganic salts or organic salt be nitrate, acetate, chloride or
Esters.
4. the preparation method of the sensor of a kind of conductive kernel sensitive layer as claimed in claim 2 and molecular sieve except wet layer,
It is characterized in that, conductive polymer polymer as described in step (1) is polyvinylpyrrolidone, the polypropylene of different molecular weight
Nitrile, polyvinyl alcohol, polymethyl methacrylate or polystyrene, wherein outer shell precursor solution, interior metal core forerunner
Different high molecular polymers should be selected in the preparation process of body.
5. the preparation method of the sensor of a kind of conductive kernel sensitive layer as claimed in claim 2 and molecular sieve except wet layer,
It is characterized in that, electric spinning device described in step (1), wherein the size of syringe needle is 0.24-0.82 mm in coaxial spinneret, outside
The size of syringe needle is 1.27-1.59 mm；The distance between spinneret and collecting board are 5-35 cm, and voltage value is 5-30 kV,
Spinneret and horizontal angle are 15-90o, syringe pump fltting speed is 0.1-0.5 ml/h.
6. the preparation method of the sensor of a kind of conductive kernel sensitive layer as claimed in claim 2 and molecular sieve except wet layer,
It is characterized in that, solvent described in step (1) is the pure solution or mixed solution of DMF, ethyl alcohol or water.
7. the preparation method of the sensor of a kind of conductive kernel sensitive layer as claimed in claim 2 and molecular sieve except wet layer,
It is characterized in that, band described in step (2) is 1.0-2.0 cm, overall diameter 0.1- there are two the length of the ceramic tube of discrete electrodes
0.5 cm, tube wall diameter are 200-300 μm, and both ends are equipped with Pt contact conductor；The length of the flat ceramic with interdigital electrode
Degree is 1-3 cm, and width is 0.8-1.0 cm, and electrode zone is 3.5 *, 1.5 mm, and inter-digital electrode width is 3.5-4.5 mm, electricity
Pole clearance is 0.3-0.5 mm.
8. the preparation method of the sensor of a kind of conductive kernel sensitive layer as claimed in claim 2 and molecular sieve except wet layer,
It is characterized in that, adhesive described in step (2) and (3) is water, ethyl alcohol or abienol.
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| CN114797762B (en) * | 2022-04-18 | 2023-07-18 | 广州滨横低碳科技有限公司 | Modified molecular sieve, preparation method thereof and application thereof in blast furnace blast dehumidification |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101939639A (en) * | 2007-12-10 | 2011-01-05 | 欧洲宇航防务集团德国有限责任公司 | Gas sensor with improved selectivity |
| CN104713915A (en) * | 2015-03-18 | 2015-06-17 | 华中科技大学 | High-performance gas sensor based on laminated structure and preparation method for high-performance gas sensor |
| CN104781666A (en) * | 2012-10-29 | 2015-07-15 | 理工研究与开发基金公司 | Sensor technology for diagnosing tuberculosis |
| KR20150134487A (en) * | 2014-05-21 | 2015-12-02 | 서울대학교산학협력단 | Fabrication method of NO2 gas sensor based on tungsten(VI) oxide nanonodule-decorated hybrid carbon nanofibers |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101156673B1 (en) * | 2009-12-16 | 2012-06-15 | 충남대학교산학협력단 | Gas sensor using porous nano-fiber containing metal oxide and manufacturing method thereof |
-
2017
- 2017-01-25 CN CN201710060535.1A patent/CN106770485B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101939639A (en) * | 2007-12-10 | 2011-01-05 | 欧洲宇航防务集团德国有限责任公司 | Gas sensor with improved selectivity |
| CN104781666A (en) * | 2012-10-29 | 2015-07-15 | 理工研究与开发基金公司 | Sensor technology for diagnosing tuberculosis |
| KR20150134487A (en) * | 2014-05-21 | 2015-12-02 | 서울대학교산학협력단 | Fabrication method of NO2 gas sensor based on tungsten(VI) oxide nanonodule-decorated hybrid carbon nanofibers |
| CN104713915A (en) * | 2015-03-18 | 2015-06-17 | 华中科技大学 | High-performance gas sensor based on laminated structure and preparation method for high-performance gas sensor |
Non-Patent Citations (3)
| Title |
|---|
| "Pd-doped TiO2 nanofiber networks for gas sensor applications";Jaehyun Moon 等;《Sensors and Actuators B: Chemical》;20100623;第149卷;第301-305页 |
| "基于氨基酸多氨基化合物氨气敏感膜的制备与应用";伍丽丽 等;《东华大学学报（自然科学版）》;20161231;第42卷(第6期);第857-862页 |
| Xiaowei Li 等."Design of Au@ZnO Yolk−Shell Nanospheres with Enhanced Gas".《ACS Applied Materials & Interfaces》.2014, |
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