CN116119718A - Gas-sensitive material and preparation method thereof, and ammonia sensor and preparation method thereof - Google Patents

Gas-sensitive material and preparation method thereof, and ammonia sensor and preparation method thereof Download PDF

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CN116119718A
CN116119718A CN202211443656.1A CN202211443656A CN116119718A CN 116119718 A CN116119718 A CN 116119718A CN 202211443656 A CN202211443656 A CN 202211443656A CN 116119718 A CN116119718 A CN 116119718A
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mos
gas
tio
sensitive material
ammonia
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毛朝勇
吴皓
黄哲
曹宇轩
戴文
刘善旺
常长志
瞿勇
李嘉福
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Wisdri Engineering and Research Incorporation Ltd
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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G39/00—Compounds of molybdenum
    • C01G39/06—Sulfides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y40/00—Manufacture or treatment of nanostructures
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G23/00—Compounds of titanium
    • C01G23/04—Oxides; Hydroxides
    • C01G23/047—Titanium dioxide
    • C01G23/053—Producing by wet processes, e.g. hydrolysing titanium salts
    • 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
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/30—Particle morphology extending in three dimensions
    • C01P2004/45—Aggregated particles or particles with an intergrown morphology
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/64—Nanometer sized, i.e. from 1-100 nanometer
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/80—Particles consisting of a mixture of two or more inorganic phases
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
    • Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters

Abstract

The invention discloses a gas-sensitive material and a preparation method thereof, an ammonia sensor and a preparation method thereof, and the composition components of the gas-sensitive material comprise MoS 2 Nanoparticles and TiO 2 Nanoparticles, tiO 2 Nanoparticles are configured to deposit and coat MoS 2 The surface of the nano-particles further forms TiO 2 /MoS 2 A complex. The invention can effectively improve the gas sensitivity of the gas sensitive material by constructing the heterojunction on the surface of the semiconductor material, and the heterojunction is compared with pure TiO 2 Pure MoS 2 In comparison with TiO 2 /MoS 2 Composite nanomaterial canTo obviously improve NH pair 3 Sensitivity of the gas.

Description

Gas-sensitive material and preparation method thereof, and ammonia sensor and preparation method thereof
Technical Field
The invention relates to the technical field of semiconductor oxide gas sensors, in particular to a gas sensitive material and a preparation method thereof, and an ammonia sensor and a preparation method thereof.
Background
The urea can be used for preparing toxic and harmful nitrogen oxides (NO x ) Selective catalytic reduction to reduce NO x The amount of emissions in the atmosphere. To accurately control the addition amount of urea to prevent NH 3 Avoiding secondary pollution to the environment, developing high-sensitivity ammonia gas sensor to NH 3 The concentration is monitored in real time, which is particularly important.
In recent years, researchers have done a lot of work around developing gas sensors that are highly sensitive, fast response/recovery, simple to manufacture, and low cost. The gas-sensitive material with excellent synthesis performance is the core for preparing the high-performance gas sensor, and among various gas-sensitive materials, transition metal sulfide attracts more and more attention, moS 2 As a typical transition metal sulfide, it is favored in the field of gas sensors for its low price and unique photoelectric properties. MoS (MoS) 2 The structure has a layered structure, wherein the single layers are internally connected by covalent bonds Mo-S, adjacent layers are mutually attracted by Van der Waals force, and the band gap can be adjusted by the number of layers. This unique structure results in the production of nano MoS 2 Tends to have a large specific surface area and gas molecules can be adsorbed on the surface of the porous material more easily, and weaker van der Waals forces between layers can cause electrons to penetrate between layers andand (3) free transfer. Research shows that based on MoS 2 Is to NH at room temperature 3 ，NO 2 HCHO and H 2 The gases all exhibit certain gas-sensitive characteristics.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a preparation method of a gas-sensitive material and the gas-sensitive material, which mainly solve the problems of pure MoS of the existing ammonia sensor 2 The technical problem of poor gas-sensitive property of the gas-sensitive material.
In order to achieve the above purpose, the invention is realized by the following technical scheme:
a preparation method of a gas-sensitive material is characterized by comprising the following steps: the method comprises the following steps:
1) Preparation of MoS 2 Nanoparticles: mixing molybdenum salt, thioacetamide and water, adding hexadecyl trimethyl ammonium bromide, performing hydrothermal reaction on the obtained mixed solution, filtering, washing and drying after the reaction is finished to obtain the MoS 2 A nanoparticle;
2) Preparation of TiO 2 /MoS 2 Composite nanomaterial: the MoS obtained in the step 1) is processed 2 Mixing nano particles, ammonium fluotitanate and water, regulating the pH of the obtained mixed solution, stirring to obtain a precipitate, drying the precipitate, and calcining in a protective atmosphere to obtain the TiO 2 /MoS 2 Composite nanomaterial. Pure MoS exposed to air 2 The gas-sensitive performance of (2) is often affected by the adsorption of oxygen on the surface, a large number of active sites on the surface are occupied by the adsorption of oxygen, and competitive adsorption with the detection gas occurs, so that the gas-sensitive performance is poor. While depositing TiO on its surface 2 The surface of the semiconductor nano material is modified to form a heterojunction, so that the pure MoS can be effectively improved 2 Is a gas-sensitive property of (2).
In the step 1), the hydrothermal reaction temperature of the mixed solution is 160-180 ℃ and the reaction time is 20-24 hours; in the step 2), the dried precipitate is calcined and heat treated at 300-500 ℃ in an argon environment, and the heat treatment time is 2 hours.
Further, in the step 2), the pH value of the mixed solution is adjusted by using ammonia water;
further, the concentration of the ammonia water is 0.1 to 0.5mol/L;
further, the pH of the mixed solution is adjusted to 7 to 8 by ammonia water.
Further, in step 1), the molybdenum salt is any one of sodium molybdate dihydrate, ammonium molybdate tetrahydrate and zinc molybdate.
Further, in the step 1), 3-5 mmol of sodium molybdate dihydrate and 10-20 mmol of thioacetamide are taken and dissolved in 50mL of deionized water, the solution is magnetically stirred for 10-30 min to obtain a uniform solution, and then 0.5-2 mmol of cetyltrimethylammonium bromide is added into the uniform solution to continuously magnetically stir for 20-40 min to obtain a mixed solution;
further, in the step 2), 0.5 to 2mmol of ammonium fluotitanate is taken and dissolved in 50mL of deionized water, and the solution is magnetically stirred for 5 to 10 minutes to obtain a uniform transparent solution; taking 0.5-2 mmol of MoS prepared in the step 1) 2 Adding the nano particles into the uniform transparent solution, and carrying out ultrasonic treatment for 5-10 min to obtain a mixed solution.
Further, the preparation method of the gas-sensitive material comprises the following steps:
1) Dissolving 3-5 mmol of sodium molybdate dihydrate and 10-20 mmol of thioacetamide in 50mL of deionized water, magnetically stirring for 10-30 min to obtain a uniform solution, adding 0.5-2 mmol of cetyltrimethylammonium bromide into the uniform solution, magnetically stirring for 20-40 min to obtain a mixed solution, performing hydrothermal reaction on the mixed solution at 160-180 ℃ for 20-24 h, cooling the reactant to room temperature to obtain a precipitate, washing the precipitate for a plurality of times, and drying to obtain MoS 2 A nanoparticle;
2) Dissolving 0.5-2 mmol of ammonium fluotitanate in 50mL of deionized water, and magnetically stirring for 5-10 min to obtain a uniform transparent solution; taking 0.5-2 mmol of MoS prepared in the step 1) 2 Adding nano particles into the uniform transparent solution, performing ultrasonic treatment for 5-10 min to obtain a mixed solution, then dropwise adding an ammonia water solution with the concentration of 0.1-0.5 mol/L into the mixed solution until the pH value of the mixed solution is 7-8, magnetically stirring for 40-50 min, and performing precipitationWashing and centrifuging for several times, and then placing the solid centrifugal product in a drying oven to be dried at 50-70 ℃; carrying out heat treatment on the dried product in an argon environment, wherein the heat treatment temperature is 300-500 ℃ to prepare TiO 2 /MoS 2 Composite nanomaterial.
Based on the same inventive concept, the invention also provides an ammonia gas sensor, which comprises an electrode element and TiO (titanium dioxide) arranged on the surface of the electrode element 2 /MoS 2 Composite coating, wherein TiO 2 /MoS 2 The composite coating is TiO formed by uniformly coating the gas-sensitive material on the surface of the electrode element 2 /MoS 2 A composite nanomaterial membrane.
Further, the electrode member has a tubular structure, and the electrode member includes Al 2 O 3 Ceramic tube and coating on Al 2 O 3 Gold electrodes at both ends of the ceramic tube and at Al 2 O 3 A heating resistance wire is arranged in the ceramic tube.
Further, the heating resistance wire is a nichrome heating resistance wire.
Further, tiO formed on the surface of the electrode member 2 /MoS 2 The film thickness of the composite nano material film is 10-20 mu m.
Further, the ammonia gas sensor obtains 80ppm NH at the working temperature of 125 DEG C 3 47.5% maximum sensitivity of the gas.
Based on the same inventive concept, the invention also provides a preparation method of the ammonia sensor, which comprises the following steps:
s1, tiO 2 /MoS 2 Placing the composite nano material in a mortar, dropwise adding ethanol, uniformly grinding the slurry for 3-5 min to paste to obtain viscous slurry, and using a clean brush to dip the viscous slurry to coat the electrode element so as to form TiO on the surface of the electrode element 2 /MoS 2 Compounding the nano material film to form a semi-finished product;
s2, drying the semi-finished product prepared in the step S1 in air for 30-60 min, then transferring the semi-finished product to an aging table, and aging for 12-24 h at 150-200 ℃ to obtain the ammonia sensor.
The technical scheme has the following advantages or beneficial effects:
according to the gas-sensitive material and the preparation method thereof, and the ammonia sensor and the preparation method thereof, moS is prepared by a simple hydrothermal method 2 Nanoparticles and with TiO 2 The nano particles are compounded to prepare the TiO 2 /MoS 2 Composite nanomaterial. And pure TiO 2 Pure MoS 2 In comparison with TiO 2 /MoS 2 The composite nano material can obviously improve the NH pair 3 Sensitivity of the gas.
Drawings
FIG. 1 is an enlarged schematic view of a gas sensor structure of a gas sensor system and an ammonia sensor therein according to an embodiment of the present invention.
FIG. 2 is an XRD pattern of the nanomaterial prepared in example 1 of the present embodiment; wherein: m represents MoS 2 Nanoparticles, T stands for TiO 2 Nanoparticles, TM stands for TiO 2 /MoS 2 Composite nanomaterial.
FIGS. 3a and 3b are diagrams of TiO's prepared in example 1 of an embodiment of the present invention 2 SEM image of nanomaterial.
FIGS. 3c and 3d are MoS prepared in example 1 of an embodiment of the present invention 2 SEM image of nanomaterial.
FIGS. 3e and 3f are diagrams of TiO's prepared in example 1 of an embodiment of the present invention 2 /MoS 2 SEM image of composite nanomaterial.
FIG. 4a is a TiO prepared in example 1 of an embodiment of the present invention 2 /MoS 2 The concentration of the composite nano material is 80ppm NH at the working temperature of 25-150 DEG C 3 Response-recovery graph of gas (a).
FIG. 4b is a TiO of example 1 according to an embodiment of the invention 2 /MoS 2 The composite nano material has the NH content of 80ppm at the working temperature of 25-175 DEG C 3 Is a sensitivity value of (a).
FIG. 5 is a TiO of example 1 according to an embodiment of the present invention 2 /MoS 2 The composite nano material is prepared for NH with different concentrations at 125 DEG C 3 Dynamic response/recovery curve of gas.
FIG. 6 is a TiO of example 1 according to an embodiment of the present invention 2 /MoS 2 The composite nano material has a NH concentration of 80ppm at 125 DEG C 3 The reproducibility of the gas was examined for curves.
Detailed Description
The invention is further described below with reference to the drawings and examples.
The following non-limiting examples will enable those of ordinary skill in the art to more fully understand the invention and are not intended to limit the invention in any way.
The test methods described in the following examples, unless otherwise specified, are all conventional; the reagents and materials, unless otherwise specified, are commercially available.
The gas sensitive test system in the following examples is Zhengzhou Weisheng technology WS-30A gas sensitive test system; the aging table is Zhengzhou Weisheng technology TS-60 aging table.
Example 1
The gas-sensitive test system and the ammonia sensor (i.e. gas sensor) used in this example are shown in fig. 1. The volume of the gas-sensitive test cavity is about 18L, and an exhaust fan, an ammonia sensor jack plate, a load resistor, a heating plate and the like are arranged in the cavity.
In this embodiment, the ammonia gas sensor includes an electrode element and TiO disposed on the surface of the electrode element 2 /MoS 2 A composite gas sensitive material coating.
Preferably, tiO 2 /MoS 2 The composite gas-sensitive material coating is prepared by using gas-sensitive material (TiO 2 /MoS 2 Composite) is uniformly coated on the surface of the electrode element to form TiO 2 /MoS 2 A composite nanomaterial membrane.
The composition of the gas-sensitive material comprises MoS 2 Nanoparticles and TiO 2 Nanoparticles, tiO 2 Nanoparticles are configured to deposit and coat MoS 2 The surface of the nano-particles further forms TiO 2 /MoS 2 A complex. Wherein MoS 2 The grain diameter of the nano-particles is 100-120 nm, and the TiO 2 The particle size of the nano particles is 10-20 nm. Formed on the electrodeTiO on the surface of the element 2 /MoS 2 The film thickness of the composite nano material film is 10-20 mu m. In this embodiment, the gas-sensitive material is prepared by hydrothermal method 2 Nanoparticles, then in MoS 2 Nano particle surface precipitation coating TiO 2 Nanoparticles, and thus produce TiO 2 /MoS 2 Composite nanomaterial.
Preferably, the electrode member has a tubular structure, and the electrode member includes Al 2 O 3 Ceramic tube and coating on Al 2 O 3 Gold electrodes at both ends of the ceramic tube and at Al 2 O 3 A heating resistance wire is arranged in the ceramic tube. Preferably, the heating resistance wire is a nichrome heating resistance wire.
The preparation method of the gas-sensitive material in the embodiment specifically comprises the following steps:
1) Dissolving 3mmol of sodium molybdate dihydrate and 10mmol of thioacetamide in 50mL of deionized water, magnetically stirring for 10min to obtain a uniform solution, and then adding 0.5mmol of cetyltrimethylammonium bromide into the uniform solution for further magnetically stirring for 20min; then the mixed solution is subjected to hydrothermal reaction for 20 hours at 160 ℃, black precipitate is obtained after the reactant is cooled to room temperature, the precipitate is washed for a plurality of times by deionized water and ethanol, and MoS is obtained after drying 2 The nano particles are ready for use;
2) Dissolving 0.5mmol of ammonium fluotitanate in 50mL of deionized water, and magnetically stirring for 5min to obtain a uniform transparent solution; taking 0.5mmol of MoS prepared in step 1) 2 Adding nanoparticle powder into the solution, performing ultrasonic treatment for 5min to obtain a mixed solution, then dropwise adding an ammonia water solution with the concentration of 0.1mol/L into the mixed solution until the pH value of the mixed solution is 7.5, magnetically stirring for 40min, washing with water, centrifuging for 3 times, and drying the solid centrifugal product in a drying oven at 60 ℃; carrying out heat treatment on the dried product in an argon environment, wherein the heat treatment temperature is 400 ℃, and preparing the TiO 2 /MoS 2 Composite nanomaterial.
Based on the TiO 2 /MoS 2 The preparation method of the ammonia gas sensor of the composite nano material comprises the following steps:
s1, tiO 2 /MoS 2 Placing the composite nano material in an agate mortar, dropwise adding ethanol, grinding the slurry at constant speed for 3min to paste, dipping the viscous slurry on an electrode element by using a clean brush, and coating the electrode element surface with the viscous slurry to form TiO with the thickness of 10 mu m 2 /MoS 2 Compounding the nano material film to form a semi-finished product;
s2, drying the semi-finished product prepared in the step S1 in air for 30min, then transferring the semi-finished product to an aging table, and aging for 12h at 150 ℃ to obtain the ammonia sensor.
In this embodiment, tiO 2 Nanoparticles, moS 2 Nanoparticle and TiO 2 /MoS 2 The X-ray diffraction pattern of the composite nano material is shown in figure 2. From TiO 2 /MoS 2 As can be seen from the diffraction pattern of the composite nano material, the purity of the composite material is higher, and the TiO is removed 2 MoS (MoS) 2 No other impurity diffraction peaks appeared. The scanning electron micrograph of the resulting material is shown in FIG. 3, and as can be seen in FIGS. 3a and 3b, tiO 2 The nano particles have obvious agglomeration phenomenon, and the particle diameter is between 10 and 20 nm; as can be seen from FIG. 3c and FIG. 3d, moS 2 The size of the nano particles is between 100 and 120nm, and the dispersibility is good; as can be seen from FIG. 3e and FIG. 3f, tiO is obtained by chemical precipitation 2 The nano particles are more uniformly distributed in MoS 2 Nanoparticle surface, and TiO 2 The nanoparticle diameter is reduced.
TiO prepared in example 1 2 /MoS 2 As can be seen from FIG. 4a, the composite nanomaterial is TiO at an operating temperature ranging from 25 to 150 DEG C 2 /MoS 2 Composite nanomaterial pair NH 3 The gas has good response/recovery characteristics (wherein the response time is generally defined as the time required for the gas sensor to reach 90% of the resistance interval change of the steady-state value of the resistance after the target gas is introduced, and the recovery time is generally defined as the time required for the gas sensor to recover to 90% of the resistance interval change of the initial resistance after the target gas is exhausted); as can be seen from FIG. 4b, tiO 2 /MoS 2 The composite nano material obtains 80ppm NH at 125 DEG C 3 Maximum sensitivity of 47.5% (Ling)Sensitivity is defined as r=Δr/R a ＝(R a -R g )/R a ) X 100%, where R a R is the resistance of the sensor in dry air g Exposure of the sensor to NH 3 Resistance in (a) and (b); tiO prepared in example 1 2 /MoS 2 The composite nano gas-sensitive material is used for preparing NH with different concentrations at 125 DEG C 3 The dynamic response/recovery curves of the gases are shown in FIG. 5, and it can be seen from FIG. 5 that 10, 20, 40, 80, 160 and 320ppm NH was continuously introduced 3 When the concentration of the introduced gas increases, the sensitivity of the composite sensor gradually increases, and the composite sensor shows good recovery characteristics; tiO (titanium dioxide) 2 /MoS 2 The composite nano material has a NH concentration of 80ppm at 125 DEG C 3 As shown in FIG. 6, the reproducibility of the gas is examined, and as can be seen from FIG. 6, 80ppm NH was continuously introduced 7 times 3 In the case of gas, the sensitivity, response-recovery time and the like of the gas are not changed basically, which indicates that the gas sensor has no response to NH 3 The gas has good stability and adsorption-desorption characteristics.
The TiO prepared in this example was tested 2 /MoS 2 NH is carried out on the base ammonia gas sensor at the working temperature of 25-175 DEG C 3 Has good gas-sensitive performance.
Example 2
The difference between this example and example 1 is that the method for producing the gas-sensitive material specifically includes the following steps:
1) Dissolving 4mmol of sodium molybdate dihydrate and 15mmol of thioacetamide in 50mL of deionized water, magnetically stirring for 20min to obtain a uniform solution, and then adding 1mmol of cetyltrimethylammonium bromide into the uniform solution for further magnetically stirring for 30min; then the mixed solution is subjected to hydrothermal reaction for 22 hours at 170 ℃, black precipitate is obtained after the reactant is cooled to room temperature, the precipitate is washed for a plurality of times by deionized water and ethanol, and MoS is obtained after drying 2 The nano particles are ready for use;
2) Dissolving 1mmol of ammonium fluotitanate in 50mL of deionized water, and magnetically stirring for 7min to obtain a uniform transparent solution; taking 1mmol of MoS prepared in step 1) 2 Adding the nanoparticle powder into the solution for ultrasonic treatmentAfter 7min, dropwise adding an ammonia water solution with the concentration of 0.25mol/L into the mixed solution until the pH value of the mixed solution is 7, magnetically stirring for 40min, washing with water, centrifuging for 3 times, and drying the product in a drying oven at 50 ℃; carrying out heat treatment on the dried product in an argon environment, wherein the heat treatment temperature is 300 ℃, and preparing the TiO 2 /MoS 2 Composite nanomaterial.
Based on the TiO 2 /MoS 2 The preparation method of the ammonia gas sensor of the composite nano material comprises the following steps:
s1, tiO 2 /MoS 2 Placing the composite nano material in an agate mortar, dropwise adding ethanol, grinding the slurry at constant speed for 4min to paste, and using a clean brush to dip the viscous slurry and coating the slurry on the electrode element to completely cover the surface of the electrode element and form TiO with the thickness of 15 mu m 2 /MoS 2 Compounding the nano material film to form a semi-finished product;
s2, drying the ceramic tube coated with the gas-sensitive material in the step S1 in air for 40min, and then moving the ceramic tube to an aging table, and aging the ceramic tube for 18h at 200 ℃ to obtain the gas-sensitive element.
The TiO prepared in this example was tested 2 /MoS 2 NH is carried out on the base ammonia gas sensor at the working temperature of 25-175 DEG C 3 Has good gas-sensitive performance.
Example 3
The difference between this example and example 1 is that the method for producing the gas-sensitive material specifically includes the following steps:
1) Dissolving 5mmol of sodium molybdate dihydrate and 20mmol of thioacetamide in 50mL of deionized water, magnetically stirring for 30min to obtain a uniform solution, and then adding 0.2mmol of cetyltrimethylammonium bromide into the uniform solution for further magnetically stirring for 40min; then the mixed solution is subjected to hydrothermal reaction for 24 hours at 180 ℃, a black precipitate is obtained after the reactant is cooled to room temperature, the precipitate is washed for a plurality of times by deionized water and ethanol, and MoS is obtained after drying 2 The nano particles are ready for use;
2) Dissolving 2mmol of ammonium fluotitanate in 50mL of deionized water, and magnetically stirring for 10min to obtain a uniform transparent solution; taking 2mmol of Mo prepared in step 1)S 2 Adding nanoparticle powder into the solution for ultrasonic treatment for 10min, then dropwise adding an ammonia water solution with the concentration of 0.5mol/L into the mixed solution until the pH value of the mixed solution is 8, magnetically stirring for 50min, washing with water, centrifuging for 4 times, and drying the product in a drying oven at 70 ℃; carrying out heat treatment on the dried product in an argon environment, wherein the heat treatment temperature is 500 ℃, and preparing the TiO 2 /MoS 2 Composite nanomaterial.
Based on the TiO 2 /MoS 2 The preparation method of the ammonia gas sensor of the composite nano material comprises the following steps:
s1, tiO 2 /MoS 2 Placing the composite nano material in an agate mortar, dropwise adding ethanol, grinding the slurry at constant speed for 5min to paste, dipping the viscous slurry on an electrode element by using a clean brush, and coating the electrode element surface with the viscous slurry to form TiO with the thickness of 20 mu m 2 /MoS 2 A composite nanomaterial film;
s2, drying the semi-finished product prepared in the step S1 in air for 30min, then transferring the semi-finished product to an aging table, and aging for 12h at 150 ℃ to obtain the ammonia sensor.
The TiO prepared in this example was tested 2 /MoS 2 NH is carried out on the base ammonia gas sensor at the working temperature of 150-250 DEG C 3 Has good gas-sensitive performance.
The embodiments are merely illustrative of the technical solution of the present invention, and not limiting thereof; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some of the technical features thereof can be replaced with equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention, and therefore all other embodiments obtained by those skilled in the art without making creative efforts are intended to fall within the protection scope of the present invention.

Claims (10)

1. A preparation method of a gas-sensitive material is characterized by comprising the following steps: the method comprises the following steps:
1) Preparation of MoS 2 Nanoparticles: mixing molybdenum salt, thioacetamide and water, adding hexadecyl trimethyl ammonium bromide, performing hydrothermal reaction on the obtained mixed solution, filtering, washing and drying after the reaction is finished to obtain the MoS 2 Nanometer scale particles;
2) Preparation of TiO 2 /MoS 2 Composite nanomaterial: the MoS obtained in the step 1) is processed 2 Mixing nano particles, ammonium fluotitanate and water, regulating the pH of the obtained mixed solution, stirring to obtain a precipitate, drying the precipitate, and calcining in a protective atmosphere to obtain the TiO 2 /MoS 2 Composite nano a material.
2. The method for producing a gas-sensitive material according to claim 1, wherein: in the step 1), the hydrothermal reaction temperature of the mixed solution is 160-180 ℃ and the reaction time is 20-24 h; in the step 2), the dried precipitate is calcined and heat treated at 300-500 ℃ in an argon environment, and the heat treatment time is 2 hours.
3. The method for producing a gas-sensitive material according to claim 1, wherein: in the step 2), the pH value of the mixed solution is regulated by ammonia water;
preferably, the concentration of the ammonia water is 0.1-0.5 mol/L;
preferably, the pH of the mixed solution is adjusted to 7 to 8 with ammonia water.
4. The method for producing a gas-sensitive material according to claim 1, wherein: in the step 1), the molybdenum salt is any one of sodium molybdate dihydrate, ammonium molybdate tetrahydrate and zinc molybdate;
preferably, the molybdenum salt is sodium molybdate dihydrate, in the step 1), 3-5 mmol of sodium molybdate dihydrate and 10-20 mmol of thioacetamide are taken and dissolved in 50mL of deionized water, the solution is magnetically stirred for 10-30 min to obtain a uniform solution, and then 0.5-2 mmol of cetyltrimethylammonium bromide is added into the uniform solution to continuously magnetically stir for 20-40 min to obtain a mixed solution;
preferably, in the step 2), 0.5-2 mmol of ammonium fluotitanate is taken and dissolved in 50mL of deionized water, and magnetically stirred for 5-10 min to obtain a uniform transparent solution; taking 0.5-2 mmol of MoS prepared in the step 1) 2 Adding the nano particles into the uniform transparent solution, and carrying out ultrasonic treatment for 5-10 min to obtain a mixed solution.
5. A gas-sensitive material produced by the production method of a gas-sensitive material according to any one of claims 1 to 4, characterized in that: the gas-sensitive material is in a nano petal shape and TiO (titanium dioxide) 2 Nano particles are coated and deposited on MoS 2 Nanoparticle surfaces.
6. The gas sensitive material of claim 5, wherein: moS (MoS) 2 Particle size of nanoparticles TiO with the particle size of 100-120 nm 2 The particle size of the nano particles is 10-20 nm.
7. An ammonia gas sensor, characterized in that: comprises an electrode element and TiO (titanium dioxide) arranged on the surface of the electrode element 2 /MoS 2 Composite coating, wherein TiO 2 /MoS 2 The composite coating is prepared by using the gas as claimed in claim 5 or 6 TiO formed by uniformly coating the surface of the electrode element with the sensitive material 2 /MoS 2 A composite nanomaterial membrane.
8. An ammonia gas sensor as defined in claim 7, wherein: the electrode element has a tubular structure and comprises Al 2 O 3 Ceramic tube and coating on Al 2 O 3 Gold electrodes at both ends of the ceramic tube and at Al 2 O 3 A heating resistance wire is arranged in the ceramic tube;
preferably, the heating resistance wire is a nichrome heating resistance wire;
preferably, the TiO is formed on the surface of the electrode member 2 /MoS 2 The film thickness of the composite nano material film is 10-20 mu m.
9. Ammonia gas according to claim 7The sensor is characterized in that: the ammonia sensor obtains 80ppm NH at the working temperature of 125 DEG C 3 47.5% maximum sensitivity of the gas.
10. A method of manufacturing an ammonia gas sensor as defined in any one of claims 7 to 9, wherein: the method comprises the following steps:
s1, tiO 2 /MoS 2 Placing the composite nano material in a mortar, dropwise adding ethanol, uniformly grinding the slurry for 3-5 min to paste to obtain viscous slurry, and using a clean brush to dip the viscous slurry to coat the electrode element so as to form TiO on the surface of the electrode element 2 /MoS 2 Compounding the nano material film to form a semi-finished product;
s2, drying the semi-finished product prepared in the step S1 in air for 30-60 min, then transferring the semi-finished product to an aging table, and aging for 12-24 h at 150-200 ℃ to obtain the ammonia sensor.
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Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN201069439Y (en) * 2006-12-21 2008-06-04 广州大学 Coating ammonia sensor
CN104502415A (en) * 2015-01-25 2015-04-08 济南大学 Preparation method of ammonia sensor structured based on precious metal composite material
CN108609657A (en) * 2018-04-20 2018-10-02 西安交通大学 A kind of titanium dioxide/molybdenum disulfide metal composite oxide micro Nano material and preparation method thereof
CN110129112A (en) * 2019-06-05 2019-08-16 青岛科技大学 A kind of flower-shaped molybdenum disulfide/titanium dioxide nanometer composite particles ER fluid and preparation method thereof
CN110180561A (en) * 2019-05-29 2019-08-30 景德镇陶瓷大学 Flower-shaped MoS2/TiO2The preparation method of catalysis material
CN111157588A (en) * 2019-12-10 2020-05-15 中国科学技术大学 Ammonia gas-sensitive sensor based on rhenium disulfide-loaded metal oxide nanocomposite and preparation method thereof
CN113125521A (en) * 2021-04-26 2021-07-16 中国石油大学(华东) MoS2/CeO2Composite gas-sensitive material and preparation method and application thereof
CN114944476A (en) * 2022-05-09 2022-08-26 桂林理工大学 MoS 2 /Fe 2 O 3 Heterostructure @ porous carbon fiber composite material and preparation method and application thereof
WO2022233225A1 (en) * 2021-05-07 2022-11-10 深圳技术大学 Method for increasing gas selection functions of multifunctional gas-sensitive sensor, and gas-sensitive sensor

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN201069439Y (en) * 2006-12-21 2008-06-04 广州大学 Coating ammonia sensor
CN104502415A (en) * 2015-01-25 2015-04-08 济南大学 Preparation method of ammonia sensor structured based on precious metal composite material
CN108609657A (en) * 2018-04-20 2018-10-02 西安交通大学 A kind of titanium dioxide/molybdenum disulfide metal composite oxide micro Nano material and preparation method thereof
CN110180561A (en) * 2019-05-29 2019-08-30 景德镇陶瓷大学 Flower-shaped MoS2/TiO2The preparation method of catalysis material
CN110129112A (en) * 2019-06-05 2019-08-16 青岛科技大学 A kind of flower-shaped molybdenum disulfide/titanium dioxide nanometer composite particles ER fluid and preparation method thereof
CN111157588A (en) * 2019-12-10 2020-05-15 中国科学技术大学 Ammonia gas-sensitive sensor based on rhenium disulfide-loaded metal oxide nanocomposite and preparation method thereof
CN113125521A (en) * 2021-04-26 2021-07-16 中国石油大学(华东) MoS2/CeO2Composite gas-sensitive material and preparation method and application thereof
WO2022233225A1 (en) * 2021-05-07 2022-11-10 深圳技术大学 Method for increasing gas selection functions of multifunctional gas-sensitive sensor, and gas-sensitive sensor
CN114944476A (en) * 2022-05-09 2022-08-26 桂林理工大学 MoS 2 /Fe 2 O 3 Heterostructure @ porous carbon fiber composite material and preparation method and application thereof

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
向斌: "二维过渡金属化合物", 28 February 2017, 中国原子能出版社, pages: 6 *
张宏;林志东;许涛;: "纳米氧化钛基气敏材料的合成与气敏性能研究", 武汉工程大学学报, no. 07, 15 July 2009 (2009-07-15) *
马东玲: "传感器与检测技术", 31 March 2020, 苏州大学出版社, pages: 154 - 156 *

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