CN110376252B - SnO (stannic oxide)2Preparation method of nano powder and transparent gas sensor - Google Patents
SnO (stannic oxide)2Preparation method of nano powder and transparent gas sensor Download PDFInfo
- Publication number
- CN110376252B CN110376252B CN201910669232.9A CN201910669232A CN110376252B CN 110376252 B CN110376252 B CN 110376252B CN 201910669232 A CN201910669232 A CN 201910669232A CN 110376252 B CN110376252 B CN 110376252B
- Authority
- CN
- China
- Prior art keywords
- sno
- nano powder
- gas
- nano
- acetic acid
- 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.)
- Expired - Fee Related
Links
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 title claims abstract description 184
- 239000011858 nanopowder Substances 0.000 title claims abstract description 78
- 238000000034 method Methods 0.000 title claims abstract description 27
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims abstract description 72
- 238000001354 calcination Methods 0.000 claims abstract description 41
- 229910021626 Tin(II) chloride Inorganic materials 0.000 claims abstract description 38
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical class [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 claims abstract description 36
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 29
- 238000002360 preparation method Methods 0.000 claims abstract description 11
- 229910021627 Tin(IV) chloride Inorganic materials 0.000 claims abstract description 8
- 238000004519 manufacturing process Methods 0.000 claims abstract description 8
- AXZWODMDQAVCJE-UHFFFAOYSA-L tin(II) chloride (anhydrous) Chemical compound [Cl-].[Cl-].[Sn+2] AXZWODMDQAVCJE-UHFFFAOYSA-L 0.000 claims abstract description 8
- HPGGPRDJHPYFRM-UHFFFAOYSA-J tin(iv) chloride Chemical compound Cl[Sn](Cl)(Cl)Cl HPGGPRDJHPYFRM-UHFFFAOYSA-J 0.000 claims abstract description 8
- XLYOFNOQVPJJNP-ZSJDYOACSA-N heavy water Substances [2H]O[2H] XLYOFNOQVPJJNP-ZSJDYOACSA-N 0.000 claims abstract description 7
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 18
- 239000007864 aqueous solution Substances 0.000 claims description 17
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 17
- 229910001868 water Inorganic materials 0.000 claims description 15
- 230000002378 acidificating effect Effects 0.000 claims description 14
- 239000011259 mixed solution Substances 0.000 claims description 14
- 238000003756 stirring Methods 0.000 claims description 14
- 239000002245 particle Substances 0.000 claims description 13
- 238000001035 drying Methods 0.000 claims description 12
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 9
- 239000011248 coating agent Substances 0.000 claims description 9
- 238000000576 coating method Methods 0.000 claims description 9
- 229910017604 nitric acid Inorganic materials 0.000 claims description 9
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical group O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 6
- 239000011521 glass Substances 0.000 claims description 6
- 239000002002 slurry Substances 0.000 claims description 6
- 239000002103 nanocoating Substances 0.000 claims description 5
- 230000008569 process Effects 0.000 claims description 5
- 239000002253 acid Substances 0.000 claims description 4
- 238000002156 mixing Methods 0.000 claims description 3
- 239000000654 additive Substances 0.000 claims description 2
- 230000000996 additive effect Effects 0.000 claims description 2
- 125000004185 ester group Chemical group 0.000 claims 1
- 230000035945 sensitivity Effects 0.000 abstract description 19
- 239000002086 nanomaterial Substances 0.000 abstract description 15
- 239000002994 raw material Substances 0.000 abstract description 13
- 239000000843 powder Substances 0.000 abstract description 12
- 230000004044 response Effects 0.000 abstract description 11
- 239000000463 material Substances 0.000 abstract description 9
- 230000003647 oxidation Effects 0.000 abstract description 9
- 238000007254 oxidation reaction Methods 0.000 abstract description 9
- 238000011160 research Methods 0.000 abstract description 3
- 230000002349 favourable effect Effects 0.000 abstract description 2
- 239000002904 solvent Substances 0.000 abstract description 2
- 239000003381 stabilizer Substances 0.000 abstract description 2
- 239000007789 gas Substances 0.000 description 80
- 239000002243 precursor Substances 0.000 description 14
- 239000000243 solution Substances 0.000 description 13
- 238000010438 heat treatment Methods 0.000 description 10
- 239000000126 substance Substances 0.000 description 9
- 238000002425 crystallisation Methods 0.000 description 8
- 230000008025 crystallization Effects 0.000 description 8
- 230000008859 change Effects 0.000 description 7
- 239000013078 crystal Substances 0.000 description 7
- 238000001514 detection method Methods 0.000 description 7
- 238000002441 X-ray diffraction Methods 0.000 description 6
- 230000032683 aging Effects 0.000 description 5
- 230000007613 environmental effect Effects 0.000 description 5
- 238000005259 measurement Methods 0.000 description 5
- 230000015572 biosynthetic process Effects 0.000 description 4
- 238000000227 grinding Methods 0.000 description 4
- 230000007062 hydrolysis Effects 0.000 description 4
- 238000006460 hydrolysis reaction Methods 0.000 description 4
- 230000004048 modification Effects 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- 239000002105 nanoparticle Substances 0.000 description 4
- 230000009467 reduction Effects 0.000 description 4
- 239000007787 solid Substances 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- 238000004458 analytical method Methods 0.000 description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 230000008020 evaporation Effects 0.000 description 3
- 238000001704 evaporation Methods 0.000 description 3
- 239000010408 film Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 239000001301 oxygen Substances 0.000 description 3
- 229910052760 oxygen Inorganic materials 0.000 description 3
- 239000004065 semiconductor Substances 0.000 description 3
- 239000000758 substrate Substances 0.000 description 3
- 238000003786 synthesis reaction Methods 0.000 description 3
- 229910001432 tin ion Inorganic materials 0.000 description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 239000000084 colloidal system Substances 0.000 description 2
- 239000008367 deionised water Substances 0.000 description 2
- 229910021641 deionized water Inorganic materials 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 150000002148 esters Chemical group 0.000 description 2
- 229910044991 metal oxide Inorganic materials 0.000 description 2
- 150000004706 metal oxides Chemical class 0.000 description 2
- 238000010899 nucleation Methods 0.000 description 2
- 230000006911 nucleation Effects 0.000 description 2
- 238000006068 polycondensation reaction Methods 0.000 description 2
- 229910052761 rare earth metal Inorganic materials 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- 239000000377 silicon dioxide Substances 0.000 description 2
- 238000003980 solgel method Methods 0.000 description 2
- KHMOASUYFVRATF-UHFFFAOYSA-J tin(4+);tetrachloride;pentahydrate Chemical compound O.O.O.O.O.Cl[Sn](Cl)(Cl)Cl KHMOASUYFVRATF-UHFFFAOYSA-J 0.000 description 2
- FWPIDFUJEMBDLS-UHFFFAOYSA-L tin(II) chloride dihydrate Chemical compound O.O.Cl[Sn]Cl FWPIDFUJEMBDLS-UHFFFAOYSA-L 0.000 description 2
- DAFHKNAQFPVRKR-UHFFFAOYSA-N (3-hydroxy-2,2,4-trimethylpentyl) 2-methylpropanoate Chemical compound CC(C)C(O)C(C)(C)COC(=O)C(C)C DAFHKNAQFPVRKR-UHFFFAOYSA-N 0.000 description 1
- MGWGWNFMUOTEHG-UHFFFAOYSA-N 4-(3,5-dimethylphenyl)-1,3-thiazol-2-amine Chemical compound CC1=CC(C)=CC(C=2N=C(N)SC=2)=C1 MGWGWNFMUOTEHG-UHFFFAOYSA-N 0.000 description 1
- 229920002799 BoPET Polymers 0.000 description 1
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- 229910052684 Cerium Inorganic materials 0.000 description 1
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 1
- 239000012190 activator Substances 0.000 description 1
- 238000000498 ball milling Methods 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000005229 chemical vapour deposition Methods 0.000 description 1
- UBEWDCMIDFGDOO-UHFFFAOYSA-N cobalt(II,III) oxide Inorganic materials [O-2].[O-2].[O-2].[O-2].[Co+2].[Co+3].[Co+3] UBEWDCMIDFGDOO-UHFFFAOYSA-N 0.000 description 1
- 229910052681 coesite Inorganic materials 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 229910052906 cristobalite Inorganic materials 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 239000002019 doping agent Substances 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000001879 gelation Methods 0.000 description 1
- 238000001027 hydrothermal synthesis Methods 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 229910052746 lanthanum Inorganic materials 0.000 description 1
- 229910001416 lithium ion Inorganic materials 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 230000010534 mechanism of action Effects 0.000 description 1
- 239000002114 nanocomposite Substances 0.000 description 1
- JCXJVPUVTGWSNB-UHFFFAOYSA-N nitrogen dioxide Inorganic materials O=[N]=O JCXJVPUVTGWSNB-UHFFFAOYSA-N 0.000 description 1
- 229910000510 noble metal Inorganic materials 0.000 description 1
- 229920000620 organic polymer Polymers 0.000 description 1
- 230000033116 oxidation-reduction process Effects 0.000 description 1
- 229920000139 polyethylene terephthalate Polymers 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 150000002910 rare earth metals Chemical class 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 230000005476 size effect Effects 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 229910052682 stishovite Inorganic materials 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- 229910001887 tin oxide Inorganic materials 0.000 description 1
- 229910052905 tridymite Inorganic materials 0.000 description 1
- 229910052727 yttrium Inorganic materials 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
- G01N27/127—Composition of the body, e.g. the composition of its sensitive layer comprising nanoparticles
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Nanotechnology (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)
Abstract
The invention relates to the technical field of nano materials and transparent gas sensors, in particular to a method for preparing SnO by a solution direct oxidation method2Nano powder of two tin salts with different valence states, i.e. SnCl4·5H2O and SnCl2·2H2O as raw material and H2Research on SnO prepared at 75-500 ℃ by using O as a solvent instead of ethanol and acetic acid as a stabilizer2The crystallinity and the gas-sensitive performance of the nano powder establish an actual model that the calcining temperature and the Sn valence have opposite influences on the gas-sensitive performance, and a transparent gas sensor with good gas-sensitive response performance to ethanol gas is designed and assembled. The powder has simple preparation method, easily obtained product and low cost, and is SnO2The nano material provides certain theoretical guidance when being used as a gas sensitive material, and the developed novel transparent sensor has the characteristics of high sensitivity and high response speed, and is favorable for popularization and application in production and life.
Description
Technical Field
The invention relates to the technical field of nano materials and gas sensors, in particular to a novel method for preparing SnO with high sensitivity and gas sensitivity by a solution direct oxidation method2Nanomaterial and transparent gas sensor.
Background
SnO, an n-type semiconductor (Eg. 3.6eV)2The metal oxide semiconductor material is considered to be a promising semiconductor metal oxide material due to the characteristics of low cost, stable physical and chemical properties and convenient and simple processing, and is widely applied to the fields of gas sensors, lithium ion batteries, super capacitors, solar batteries and the like. SnO2Has high reactivity to reducing gas at lower temperature, is easy to adsorb oxygen, and can be used as SnO2After reaching the nm level, the material has very high specific surface area and quantum size effect, and is used for improving the gas of the gas sensitive elementThe sensitivity properties are very helpful. SnO2The particle size of the powder, the shape, uniformity and stability of the particles directly influence important parameters of the prepared gas sensitive device, such as sensitivity, power consumption, response recovery characteristics, stability and the like. It was earlier thought that after noble metal addition, the SnO was2The formation of metal clusters on the surface of the grains can generate additional adsorption sites on which the gas undergoes catalytic oxidation-reduction. However, polycrystalline SnO2The mechanism of action with the reducing gas is more complex. It includes: SnO2Loss of lattice oxygen, modification of the tin oxidation state, and formation of new bonds between the intrinsic metal and the dopant metal. Currently, synthetic SnO is commonly used2The methods of the nano material mainly include a chemical vapor deposition method, a sol-gel method, a hydrothermal method and the like. SnO by Choi, U-Sung et al2、Co3O4Mechanically ball-milling a series of powders for 24H, and heat treating to obtain nano composite powder in the presence of CO and H2Good n-type response behavior was shown in isoreductive atmospheres (Choi, U-Sung et al, Sensors and activators B: Chemical, 2004, 98: 166); neftali et al use organic polymers Sn (OR)4Ultrafine tin oxide particles doped with rare earth elements Ce, Y and La are prepared as precursors, have a particle size of 20nm and excellent gas sensing performance (Carreno, Neftali LV and the like, Journal of nanoparticie Research, 2009, 11: 955); wanghun et al prepared pure SnO by hydrolysis method2The nano material optimizes the synthesis condition through orthogonal experiment, compares the characteristics of constant-temperature hydrolysis and microwave hydrolysis, adopts static gas distribution method to test gas-sensitive property, and the result shows that the microwave hydrolysis method can be used to obtain uniform and fine SnO2The nanometer material greatly shortens the synthesis reaction time, increases the concentration of the reactant for gelling, and obviously improves the production efficiency (Journal of Rare Earth, 2010, 28: 171, New King, etc.). The key technology of the traditional sol-gel method is the preparation technology of the sol, and the SnCl is used for multiple purposes4An aqueous solution is used as a precursor. However, the kind of the starting material salt, the calcination temperature, SnO2The structure and the like of the SnO have further needs to be perfected to solve the problem of the SnO2Poor stability and selectivity of gas sensorPoor quality and the like.
Disclosure of Invention
The present invention aims at solving the above problems by improving the original preparation method and providing a novel solution direct oxidation process for increasing SnO2Gas-sensitive property of the nano material.
The invention realizes the purpose through the following technical scheme: high-sensitivity SnO2The preparation method of nano powder adopts two tin salts with different valence states to prepare a precursor, namely SnCl is respectively selected4·5H2O and SnCl2·2H2O, prepared by a novel solution direct oxidation process comprising the steps of:
(1) adding acetic acid into water to obtain an acidic aqueous solution;
the volume ratio of acetic acid to water in the acidic aqueous solution is 25: 150-350, preferably 25: 270;
(2) slowly dripping the mixed solution of tin salt and acetic acid into the acidic aqueous solution obtained in the step (1) with the constant temperature of 30 ℃ under the stirring state, continuing stirring for 2-6h after dripping is finished, standing and aging for 72-120h to obtain SnO2Sol;
the tin salt is SnCl4·5H2O or SnCl2·2H2O; the ratio relation of the tin salt to the acetic acid in the mixed solution of the tin salt and the acetic acid is 0.1 mol: 20-40mL, preferably 0.1 mol: 30 mL; the volume of the mixed solution of the tin salt and the acetic acid and the acid aqueous solution is 4.375-18.75: 1, preferably 9.83: 1;
(3) SnO obtained in step (2)2Calcining the sol at 75-500 deg.C (e.g., 75 deg.C, 250 deg.C, 500 deg.C) for 2-40h (e.g., 40h, 15h, 2h) to obtain SnO2And (3) nano powder.
Preferably, the acetic acid can be replaced by hydrochloric acid or nitric acid; when the hydrochloric acid or nitric acid is used, the dosage of the hydrochloric acid or nitric acid is 1/6-1/8 of the volume of acetic acid.
Preferably, the rotation speed of the stirring is 100-600 r/min.
Preferably, the slow addition is a dropwise addition, such as 5-10 mL/min.
The invention also relates to the protection of SnO prepared by means of the above-mentioned method2The average particle size of the nano powder is 3.42nm-22.42 nm.
The present invention also provides a transparent gas sensor using the above-described SnO2And (4) preparing nano powder.
The preparation method of the transparent gas sensor comprises the following steps:
(1) the prepared SnO2Mixing the nano material with water, adding a film-forming assistant, and preparing into slurry;
(2) uniformly coating the slurry obtained in the step (1) on a glass carrier, and drying to obtain SnO2Nano-coating
(3) SnO obtained in step (2)2And coating an Ag electrode on the surface of the nano coating to prepare the transparent gas sensor.
Wherein: SnO2Nano powder: water: the mass ratio of the film-forming additive is 1: 1-2: 0.05-0.2; SnO2The proportional relation between the area of the coating and the size is 5-20cm2：1g。
Preferably, the drying temperature is 250 ℃, and the drying time is 1-3 h;
preferably, the coalescing agent is ester alcohol 12.
Preferably, the glass support is a silica glass support.
Preferably, the coating shape of the Ag electrode is designed into a three-fork type in order to increase the conductive efficiency of the Ag electrode.
In the above transparent sensor structure, based on SnO2The gas sensor made of the material has different sensitivities to different reducing gases (such as carbon monoxide, ethanol, nitrogen dioxide and the like) at different working temperatures, so that the gas sensor can be suitable for detecting harmful gases in local environments. However, since the resistance of the sensor is affected by the working environment (temperature, humidity and other gases), especially for the direct-heating gas sensor, the heat capacity of the sensitive and heating components is relatively small, the response speed to the gas is relatively fast, and the sensor is easily affected by the ambient temperature. Whether by voltage sourceThe current source supplies power to the heating wires, and when the ambient temperature changes, the temperature of the heating wires can be changed, so that the accuracy and the stability of the detection of the sensor are influenced. The invention adopts digital PI control, adds a heating electrode, optimizes the structure of the sensor, keeps the heating resistance at a constant value, and leads the sensor to work at a stable absolute temperature, thereby eliminating the influence of the change of the environmental temperature on the sensor. The detection of the ethanol gas and the analysis of the experimental result show that the method can effectively inhibit the influence of the environmental temperature on the gas sensor.
Preferably, SnO prepared from stannous salts2The nano material has smaller grain size and has better gas-sensitive performance when the calcining temperature is lower; SnO prepared from tetravalent tin salt2The nano material has larger grain size and better gas sensitivity when the calcining temperature is higher; calcining at 250 deg.C with SnCl when the ethanol concentration in the reducing gas is 500ppm2·2H2SnO produced from O2Nano material and SnCl calcined at 500 deg.C4·5H2SnO produced from O2The gas-sensitive sensing response of the nano material is the best, and the resistance ratio of the sensor in air and target gas is approximately the same and is about 3.5, so that the gas-sensitive performance is very excellent. Wherein the sensing response SGDefined as the ratio of Ra/Rg, which are the resistances of the sensor in air and the target gas, respectively.
In particular, the invention can prepare SnO by a direct solution oxidation method at low temperature2Nanopowders, process for broadening SnO2The preparation method of the nano powder has great novelty.
The invention utilizes the small size and the film form to prepare the transparent sensing device, and mainly utilizes SnO2The transparent gas sensor is proposed for the first time, and is expected to expand the range of use of the gas sensor.
The highest gas sensitivity of the transparent gas sensor reaches 3.5 times, namely, when gas is detected, the resistivity of the sensor is reduced by 3.5 times. This indicates that the transparent gas sensor is ideally applicable, and the transparent gas sensor is expected to play a large role in gas detection.
Has the advantages that:
the invention prepares SnO by a novel solution direct oxidation method2Nano powder of two tin salts with different valence states, i.e. SnCl4· 5H2O and SnCl2·2H2O as raw material and H2O replaces ethanol to be used as a solvent, acetic acid is used as a stabilizer, and research on SnO prepared under the conditions of 75-500 ℃ (low and medium temperatures, namely 75 ℃, 250 ℃ and 500 ℃) at three different calcination temperatures2The crystallinity and the gas-sensitive performance of the nano powder establish an actual model that the calcining temperature and the Sn valence have different influences on the gas-sensitive performance, and a transparent gas sensor is designed and assembled, and has good gas-sensitive response performance to ethanol gas. The preparation method of the powder has the advantages of simple operation, easily obtained product and low cost, and is SnO2The nano material provides a certain theoretical guidance when being used as a gas sensitive material, the newly-proposed transparent gas sensor is favorable for popularization and application in production and life, the highest gas sensitivity reaches 3.5 times, namely, when detecting gas, the resistivity reduction range of the sensor is 3.5 times of the original resistivity reduction range, and the method can effectively inhibit the influence of the environmental temperature on the gas sensor through the detection of ethanol gas and the analysis of the experimental result of the ethanol gas, so that the developed novel transparent sensor has the characteristics of wide detection range, high sensitivity, high precision, high response speed and good interchangeability, and can ensure the accuracy of automatic production detection and control.
Drawings
FIG. 1 shows SnCl in example 14·5H2SnO prepared from precursors prepared from O and other substances at different calcining temperatures2XRD pattern of nano powder.
FIG. 2 shows SnCl in example 22·2H2SnO prepared from precursors prepared from O and other substances at different calcining temperatures2XRD pattern of nano powder.
FIG. 3 is a schematic view of a transparent gas sensor according to the present invention;
in the figure: 1. heating electrode, 2.SnO2Nano coating, 3. measuring electrode, 4.SiO2A glass carrier.
FIG. 4 is SnO2A nano powder gas sensitivity measuring system;
in the figure: 5. the device comprises a magnetic constant temperature heater, 6 an evaporation pan, 7 a sample (gas sensitive element), 8.1L of a beaker, 9 an iron stand, 10 an injector, 11 copper wires, 12 a multimeter, 9 PET thin film and 10 a thermometer.
FIG. 5 is a graph of SnO prepared from tin salts with different alcohol concentrations and different valence states at different calcination temperatures2And (3) a gas-sensitive sensing response diagram of the nano powder.
Detailed Description
The following non-limiting examples will allow one of ordinary skill in the art to more fully understand the present invention, but are not intended to limit the invention in any way.
Example 1
Tin salt SnCl4·5H2SnO prepared by taking O as precursor at different calcining temperatures2The nano powder comprises the following steps:
(1) 270ml of water is put into a beaker, 25ml of acetic acid is added until the pH value of the solution is equal to 2 to obtain an acidic aqueous solution, and the beaker is continuously stirred on a magnetic stirrer of 300r/min at the temperature of 30 ℃.
(2) 35.06g of tin tetrachloride pentahydrate (SnCl) were weighed out4·5H2O, 0.1mol) of the solid was added to another beaker, and 30ml of acetic acid was added thereto and dissolved to obtain a mixed solution of a tin salt and acetic acid.
(3) Dropwise adding the mixed solution of the tin salt and the acetic acid obtained in the step (2) into the acidic aqueous solution obtained in the step (1) in a stirring state at the speed of 300r/min, continuously stirring for 2h after dropwise adding is finished, standing and aging for 72h to obtain SnO2And (3) sol.
(4) SnO obtained in the step (3)2The sol is respectively calcined for 40h, 15h and 2h at 75 ℃, 250 ℃ and 500 ℃ to obtain three SnO parts by careful grinding2And (3) nano powder. Wherein SnO is obtained by calcining at 75 ℃ for 40h2The nano powder is marked as SnO No. one2Nano powder; SnO obtained by calcining at 250 ℃ for 15h2Nano meterThe powder is marked as No. two SnO2The particle size value of the nano powder is 4.73 nm; SnO obtained by calcining at 500 ℃ for 2h2The nano powder is marked as No. three SnO2The particle size of the nano powder is 22.42 nm.
FIG. 1 shows SnCl4·5H2SnO prepared from precursors prepared from O and other substances at different calcining temperatures2XRD pattern of nano powder. As can be seen from FIG. 1, Sn is used4+The nano powder after drying and thermal crystallization treatment at the temperature of 75 ℃ of colloid prepared from raw materials such as tin salt and the like is of an amorphous structure, and SnO is not formed2And (4) crystals. Possibly due to SnCl in a low-temperature drying system4The water in the hydrosol is slowly evaporated, the polycondensation reaction between the hydrosol solutions is slow, the time for converting the hydrosol solutions into gel is long, three strong peaks do not appear at the moment, an amorphous peak is displayed, and the sol has no crystallization phenomenon. And SnCl4·5H2Sn prepared under O substance reaction system4+Passing powder obtained by calcining a sample at 250 ℃ and 500 ℃ through SnO2Compared with standard maps, the standard maps are all SnO2A crystalline form. When the calcination temperature is 500 ℃, the peak value of the diffraction peak in the obtained XRD is sharper, which shows that the obtained XRD has better crystallization performance, no other substances are generated, and the obtained XRD is SnO which is obtained at 250 ℃ and has lower crystallization temperature2Since the XRD pattern formed by the nano-material powder is narrow in full width at half maximum and small in grain size, it is known that Sn is contained in the nano-material powder4+When the precursor prepared by using the tin salt as the raw material is calcined, the synthesized SnO is heated at a higher temperature2The nano powder has larger grain diameter and better crystallization property. The mechanism may be that the higher the temperature, the more easily the water evaporates, the faster the polycondensation reaction, and the less easily the particles agglomerate, so that the most initial SnCl occurs4Better oxidation to SnO2The time of gelation is shortened, the nucleation and growth of nano particles are better at the moment, and the prepared SnO2The nano powder has the advantages of complete crystal grain development and good crystallization performance.
Example 2
Tin salt SnCl2·2H2SnO prepared by taking O as precursor at different calcining temperatures2The nano powder comprises the following steps:
(1) 270ml of water is placed in a beaker, 25ml of acetic acid is added until the pH value of the solution is equal to 2, an acidic aqueous solution is obtained, and the beaker is stirred continuously on a magnetic stirrer at 300r/min at 30 ℃.
(2) 22.5g of tin dichloride dihydrate (SnCl) were weighed out2·2H2O, 0.1mol) of the solid was added to another beaker, and 30ml of acetic acid was added thereto and dissolved to obtain a mixed solution of a tin salt and an acid.
(3) Dropwise adding the mixed solution of the tin salt and the acid obtained in the step (2) into the acidic aqueous solution obtained in the step (1) in a stirring state at the speed of 300r/min, continuously stirring for 2h after dropwise adding is finished, standing and aging for 72h to obtain SnO2And (3) sol.
(4) SnO obtained in the step (3)2The sol is respectively calcined for 40h, 15h and 2h at 75 ℃, 250 ℃ and 500 ℃ to obtain three SnO parts by careful grinding2And (3) nano powder. Wherein SnO is obtained by calcining at 75 ℃ for 40h2The nano powder is marked as No. four SnO2Nano powder; SnO obtained by calcining at 250 ℃ for 15h2The nano powder is marked as No. five SnO2The particle size value of the nano powder is 3.42 nm; SnO obtained by calcining at 500 ℃ for 2h2The nano powder is marked as No. six SnO2The particle size of the nano powder is 18.34 nm.
FIG. 2 shows SnCl2·2H2SnO prepared from precursors prepared from O and other substances at different calcining temperatures2XRD pattern of nano powder. As can be seen from FIG. 2, Sn is used2+The colloid prepared from the tin salt and other raw materials has a crystalline structure no matter at 75 ℃, 250 ℃ or 500 ℃, but the three-strong peak of the nano powder calcined at 75 ℃ is obviously different from the other two, and the three-strong peak is found to be different from the SnCl according to a standard map2The three strong peaks are identical, which indicates that SnCl in the raw material2Is not oxidized into unstable SnO by oxygen and becomes SnO2And (4) crystals. The calcination temperature of 250 ℃ shows three strong peaks, but the half height width is very wide, the diffraction peak is also low, which shows that the crystal is poor, the long range of the atomic arrangement is not so regular, but the short range order is not so regularThere are many amorphous phases inside, and the atoms are arranged in a disordered manner but are still SnO2And (4) crystals. In contrast, when the calcination temperature is 500 ℃, the peak value of the diffraction peak in the obtained XRD pattern is sharp, and the full width at half maximum is narrow, which indicates that the crystallization property is good, and no other substances are generated. It was concluded that Sn is contained2+The synthesized SnO with lower temperature is calcined by the precursor prepared by the tin salt as the raw material2The particle size of the nano particles is smaller, and the performance is more excellent. Probably due to the high temperature favoring Sn4+The oxidation and growth of ions have better promotion effect on the nucleation and production of the nano particles and better crystallization effect.
Example 3
Tin salt SnCl4·5H2SnO prepared by taking O as precursor at different calcining temperatures2The nano powder comprises the following steps:
(1) 270ml of water are placed in a beaker, 4.17ml of hydrochloric acid are added until the pH value of the solution is equal to 2, an acidic aqueous solution is obtained, and the beaker is stirred constantly on a magnetic stirrer at 300r/min at 30 ℃.
(2) 35.6g of tin tetrachloride pentahydrate (SnCl) are weighed out4·5H2O) the solid was added to another beaker, and 5ml of hydrochloric acid was further added to dissolve it, to obtain a mixed solution of a tin salt and hydrochloric acid.
(3) Dropwise adding the mixed solution of the tin salt and the hydrochloric acid obtained in the step (2) into the acidic aqueous solution obtained in the step (1) in a stirring state at the speed of 300r/min, continuously stirring for 2h after dropwise adding is finished, standing and aging for 72h to obtain SnO2And (3) sol.
(4) SnO obtained in the step (3)2The sol is respectively calcined for 40h, 15h and 2h at 75 ℃, 250 ℃ and 500 ℃ to obtain three SnO parts by careful grinding2And (3) nano powder. Wherein SnO is obtained by calcining at 75 ℃ for 40h2The nano powder is marked as No. seven SnO2Nano powder; SnO obtained by calcining at 250 ℃ for 15h2The nano powder is marked as No. eight SnO2Nano powder; SnO obtained by calcining at 500 ℃ for 2h2Nano-powder is marked as NO. nine SnO2And (3) nano powder.
Example 4
Tin salt SnCl2·2H2SnO prepared by taking O as precursor at different calcining temperatures2The nano powder comprises the following steps:
(1) 270ml of water are placed in a beaker, 3.125ml of nitric acid are added until the pH value of the solution is equal to 2, an acidic aqueous solution is obtained, and the beaker is stirred continuously on a magnetic stirrer at 300r/min at 30 ℃.
(2) 22.5g of tin dichloride dihydrate (SnCl) were weighed out2·2H2O) the solid was added to another beaker, and 3.75ml of nitric acid was added and dissolved to obtain a mixed solution of tin salt and nitric acid.
(3) Dropwise adding the mixed solution of the tin salt and the nitric acid obtained in the step (2) into the acidic aqueous solution obtained in the step (1) in a stirring state at the speed of 300r/min, continuously stirring for 2h after dropwise adding is finished, standing and aging for 72h to obtain SnO2And (3) sol.
(4) SnO obtained in the step (3)2The sol is respectively calcined for 40h, 15h and 2h at 75 ℃, 250 ℃ and 500 ℃ to obtain three SnO parts by careful grinding2And (3) nano powder. Wherein SnO is obtained by calcining at 75 ℃ for 40h2The nano powder is marked as No. ten SnO2Nano powder; SnO obtained by calcining at 250 ℃ for 15h2The nano-powder is marked as No. eleven SnO2Nano powder; SnO obtained by calcining at 500 ℃ for 2h2The nano-powder is marked as No. twelve SnO2And (3) nano powder.
Example 5
SnO No. two and SnO No. three in example 1 are respectively added2Nano powder and No. five and No. six SnO in example 22The nano powder is prepared into a transparent gas sensor, wherein the substrate of the transparent gas sensor is designed into a thin cylinder shape with the thickness of 2mm, and insulating silicon dioxide glass is used as a carrier. The cross-section of the substrate has a circular radius of 10mm and an area of about 31.4mm2. Gas-sensitive material SnO2Mixing with deionized water, adding Eschmann TEXANOL film forming assistant (ester alcohol 12), preparing into slurry, uniformly coating the slurry on silica glass carrier, drying in drying oven, taking out, and SnO2Ag electrode coated on surface of nano coatingAnd preparing the transparent gas sensor. Wherein SnO2Nano powder: deionized water: the film-forming assistant is 1 g: 2 g: 0.2 g; the drying temperature is 250 ℃, and the drying time is 2 h; SnO2The proportional relation between the area of the coating and the size is 10cm2: 1g of a compound; the measuring electrode and the heating electrode are arranged on the upper surface of the substrate, the electrode is made of Ag, the shape schematic diagram is shown in figure 3, the measuring electrode is provided with three interdigital parts distributed on SnO2And finally, the material areas are gathered at the same pin, and a copper wire is connected with a test electrode on the gas sensor and a universal meter so as to test the resistance value change of the gas sensor under different concentrations. The invention adopts digital PI control, adds a heating electrode, optimizes the structure of the sensor, keeps the heating resistance at a constant value, and leads the sensor to work at a stable absolute temperature, thereby eliminating the influence of the change of the environmental temperature on the sensor.
Example 6
FIG. 4 is SnO2The sensitivity measurement system for the nano powder gas is used for carrying out sensitivity test on four transparent gas sensors in the embodiment 5. The measurement was carried out in a beaker (volume 1L) sealed with a PET film (cf. Liu, S., L.Li, W.Jiang, C.Liu, W.Ding, and W.Chai.Crystal and morphology-controlled synthesis of SnO2nanoparticles for high gas sensitivity powder Technology,2013(245): 168-2Gas sensors), evaporation pans, and thermometers. The temperature in the beaker is measured and controlled by a magnetic constant temperature heater, and the temperature change in the measuring process is accurately monitored by a thermometer so as to ensure SnO2The film temperature was constant at 150 ℃. For measurement, ethanol was injected into the evaporation dish for measurement with a 1mL syringe, and ethanol vapor was formed at 150 ℃. The ethanol vapor concentrations were 100ppm, 200ppm, 300ppm, 400ppm and 500ppm, respectively, and SnO was treated with a multimeter2The resistivity change of the gas sensor is monitored and recorded in real time, so that the resistance change data can be analyzed. Sensor response SGDefined as the Ra/Rg ratio, where Ra and Rg are the resistances before and after exposure of the sensor to ethanol vapor, respectively.
The measurement results are shown in FIG. 5, and SnO prepared from a stannous salt as a raw material at a calcination temperature of 250 ℃ is obtained2The gas-sensitive property of the nano powder is superior to that of the powder prepared at a higher temperature, namely 500 ℃, and SnO prepared by taking tetravalent tin salt as a raw material at a calcination temperature of 500 DEG C2The gas sensitivity of the nano powder is better than that of the powder obtained by the precursor at 250 ℃. This is because SnO2The gas-sensitive property of the nano powder is related to factors such as crystal form, particle size, crystallinity and the like, so that under the same calcining temperature, when the valence states of the adopted raw material tin ions are different, the gas sensitivity with larger difference can be shown. Therefore, when the valence state of tin ions in the tin salt is divalent, the nano powder with lower calcining temperature and small grain size has good gas-sensitive performance; when the valence state of the raw material containing tin ions is quadrivalence, the nano powder with high calcination temperature and large grain size has good gas-sensitive performance. As can be seen from FIG. 4, SnO prepared from a stannous tin salt as a raw material at a calcination temperature of 250 ℃ is obtained2Nano powder and SnO prepared from tetravalent tin salt as raw material at 500 deg.C calcining temperature2The gas sensitivity of the nano powder is the highest, the sensitivity of the nano powder and the sensitivity of the nano powder are both 3.5 times, namely when gas is detected, the resistivity reduction range of the two sensors is one third of the original resistivity reduction range, and the detection of the ethanol gas and the analysis of the experimental result show that the method can effectively inhibit the influence of the environmental temperature on the gas sensors.
It will be apparent to those skilled in the art from this disclosure that many changes and modifications can be made, or equivalents modified, in the embodiments of the invention without departing from the scope of the invention. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention shall still fall within the protection scope of the technical solution of the present invention, unless the contents of the technical solution of the present invention are departed.
Claims (10)
1. SnO (stannic oxide)2The preparation method of the nano powder is characterized by comprising the following steps: the method comprises the following steps:
(1) adding acetic acid into water to obtain an acidic aqueous solution;
the volume ratio of acetic acid to water in the acidic aqueous solution is 25: 150-;
(2) slowly dripping a mixed solution of tin salt and acetic acid into the acidic aqueous solution obtained in the step (1) at the constant temperature of 30 ℃ under the stirring state, continuing stirring for 2-6h after dripping is finished, and standing for 72-120h to obtain sol;
the tin salt is SnCl4·5H2O or SnCl2·2H2O; the ratio relation of the tin salt to the acetic acid in the mixed solution of the tin salt and the acetic acid is 0.1 mol: 20-40 mL; the volume of the mixed solution of the tin salt and the acetic acid and the acid aqueous solution is 4.375-18.75: 1;
(3) calcining the sol obtained in the step (2) at 75-500 ℃ for 2-40h to obtain SnO2And (3) nano powder.
2. A SnO according to claim 12The preparation method of the nano powder is characterized by comprising the following steps: the acetic acid is replaced by hydrochloric acid or nitric acid; the dosage of the hydrochloric acid or the nitric acid is 1/6-1/8 of the volume of the acetic acid.
3. A SnO according to claim 12The preparation method of the nano powder is characterized by comprising the following steps: the slow dripping is dropwise dripping.
4. A SnO according to claim 12The preparation method of the nano powder is characterized by comprising the following steps: the rotating speed of the stirring is 100-600 r/min.
5. SnO produced by the process of any of claims 1 to 42And (3) nano powder.
6. A SnO according to claim 52The nano powder is characterized in that: the SnO2The average particle diameter of the nano powder is 3.42nm-22.42 nm.
7. A transparent gas sensor, characterized by: by usingThe SnO as claimed in claim 5 or 62And (4) preparing nano powder.
8. The method for manufacturing a transparent gas sensor according to claim 7, wherein: the method comprises the following steps:
(1) SnO prepared according to claim 5 or 62Mixing the nano powder with water, adding a film-forming assistant, and preparing into slurry;
(2) uniformly coating the slurry obtained in the step (1) on a glass carrier, and drying to obtain SnO2A nano-coating;
(3) SnO obtained in step (2)2Coating Ag electrodes on the surfaces of the nano coatings to prepare transparent gas sensors;
wherein SnO2Nano powder: water: the mass ratio of the film-forming additive is 1: 1-2: 0.05-0.2; SnO2The proportional relation between the area of the coating and the size is 5-20cm2：1g。
9. The method for manufacturing a transparent gas sensor according to claim 8, wherein: the drying temperature is 250 deg.C, and the drying time is 1-3 h.
10. The method for manufacturing a transparent gas sensor according to claim 8, wherein: the film-forming assistant is ester alcohol 12; the glass carrier is a silica glass carrier.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910669232.9A CN110376252B (en) | 2019-07-24 | 2019-07-24 | SnO (stannic oxide)2Preparation method of nano powder and transparent gas sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910669232.9A CN110376252B (en) | 2019-07-24 | 2019-07-24 | SnO (stannic oxide)2Preparation method of nano powder and transparent gas sensor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110376252A CN110376252A (en) | 2019-10-25 |
| CN110376252B true CN110376252B (en) | 2022-03-08 |
Family
ID=68255252
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910669232.9A Expired - Fee Related CN110376252B (en) | 2019-07-24 | 2019-07-24 | SnO (stannic oxide)2Preparation method of nano powder and transparent gas sensor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110376252B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110918007B (en) * | 2019-11-04 | 2022-04-22 | 江苏一夫新材料产业技术研究院有限公司 | PVP polymerized SnO2-graphene aerogels and method for the production thereof |
| CN111982981B (en) * | 2020-08-17 | 2022-09-30 | 微纳感知(合肥)技术有限公司 | SnO (stannic oxide) 2 Gas-sensitive material, preparation method and application thereof |
| CN113189151A (en) * | 2021-04-30 | 2021-07-30 | 重庆文理学院 | High-response high-thermal-stability tin dioxide sensor and preparation method thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101696029A (en) * | 2009-10-14 | 2010-04-21 | 大连交通大学 | Method for directly synthesizing liquid phase of tin oxide nano powder |
| CN104677879A (en) * | 2015-02-11 | 2015-06-03 | 中国科学院金属研究所 | Flexible and transparent gas sensor based on semiconductive single-walled carbon nanotube |
| CN106865600A (en) * | 2017-03-17 | 2017-06-20 | 大连交通大学 | A kind of preparation method of size tunable stannic oxide nano powder |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2982650A1 (en) * | 2014-08-07 | 2016-02-10 | Honeywell International Inc. | Method and system for flammable gas detection |
-
2019
- 2019-07-24 CN CN201910669232.9A patent/CN110376252B/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101696029A (en) * | 2009-10-14 | 2010-04-21 | 大连交通大学 | Method for directly synthesizing liquid phase of tin oxide nano powder |
| CN104677879A (en) * | 2015-02-11 | 2015-06-03 | 中国科学院金属研究所 | Flexible and transparent gas sensor based on semiconductive single-walled carbon nanotube |
| CN106865600A (en) * | 2017-03-17 | 2017-06-20 | 大连交通大学 | A kind of preparation method of size tunable stannic oxide nano powder |
Non-Patent Citations (4)
| Title |
|---|
| "SnO2纳米粒子的粒径调控";廖照江 等;《数字技术与应用》;20100129;第106页 * |
| One‑pot synthesis and gas sensitivity of SnO2 nanoparticles prepared;Jing Wang 等;《Applied Physics A》;20191217;第1-7页 * |
| SnO2纳米粒子制备及其应用研究进展;梁冬冬 等;《中国陶瓷工业》;20170831;第47-52页 * |
| 廖照江 等."SnO2纳米粒子的粒径调控".《数字技术与应用》.2010, * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110376252A (en) | 2019-10-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Yin et al. | Tin dioxide nanoparticles with high sensitivity and selectivity for gas sensors at sub-ppm level of hydrogen gas detection | |
| CN110376252B (en) | SnO (stannic oxide)2Preparation method of nano powder and transparent gas sensor | |
| Qi et al. | Electrical response of Sm2O3-doped SnO2 to C2H2 and effect of humidity interference | |
| Hermawan et al. | One-step synthesis of micro-/mesoporous SnO2 spheres by solvothermal method for toluene gas sensor | |
| McCue et al. | SnO2− In2O3 Nanocomposites as Semiconductor Gas Sensors for CO and NO x Detection | |
| Wang et al. | Humidity-sensing performance of 3DOM WO3 with controllable structural modification | |
| Lu et al. | Effects of sintering temperature on sensing properties of WO3 and Ag-WO3 electrode for NO2 sensor | |
| Yin et al. | Sensing selectivity of SnO2-Mn3O4 nanocomposite sensors for the detection of H2 and CO gases | |
| Majumdar | The effects of crystallite size, surface area and morphology on the sensing properties of nanocrystalline SnO2 based system | |
| Bahadur et al. | Selective gas sensing response from different loading of Ag in sol–gel mesoporous titania powders | |
| Sheng et al. | Humidity sensing properties of bismuth phosphates | |
| Zhang et al. | Er-enhanced humidity sensing performance in black ZnO-based sensor | |
| Li et al. | High-response and low-temperature nitrogen dioxide gas sensor based on gold-loaded mesoporous indium trioxide | |
| US6134946A (en) | Nano-crystalline porous tin oxide film for carbon monoxide sensing | |
| Harale et al. | Single-step hydrothermally grown nanosheet-assembled tungsten oxide thin films for sensitive and selective NO 2 gas detection | |
| Samerjai et al. | Highly selective hydrogen sensing of Pt-loaded WO3 synthesized by hydrothermal/impregnation methods | |
| Benamara et al. | High response to sub-ppm level of NO 2 with 50% RH of ZnO sensor obtained by an auto-combustion method | |
| Yang | Nanocomposite films for gas sensing | |
| Addabbo et al. | Gas sensing properties of YMnO3 based materials for the detection of NOx and CO | |
| Wang et al. | Mixed potential type ppb-level acetaldehyde gas sensor based on stabilized zirconia electrolyte and a NiTiO3 sensing electrode | |
| Vijayalakshmi et al. | Novel two-step process for the fabrication of MnO2 nanostructures on tantalum for enhanced electrochemical H2O2 detection | |
| CN102442787B (en) | Nano air-sensitive thin film and preparation method thereof | |
| Xu et al. | Vanadium-doped tin oxide porous nanofibers: Enhanced responsivity for hydrogen detection | |
| Nidhi et al. | Single-pot hydrothermal derived TiO2/SBA-16 cubic mesoporous nanocomposite for humidity sensing | |
| Epifani et al. | Nanocrystals as Very Active Interfaces: Ultrasensitive Room-Temperature Ozone Sensors with In2O3 Nanocrystals Prepared by a Low-Temperature Sol− Gel Process in a Coordinating Environment |
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 | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20220308 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |