CN109592713B - Tungsten trioxide hollow nanosphere semiconductor material and preparation method thereof, gas sensor and preparation method and application thereof - Google Patents

Tungsten trioxide hollow nanosphere semiconductor material and preparation method thereof, gas sensor and preparation method and application thereof Download PDF

Info

Publication number
CN109592713B
CN109592713B CN201910006199.1A CN201910006199A CN109592713B CN 109592713 B CN109592713 B CN 109592713B CN 201910006199 A CN201910006199 A CN 201910006199A CN 109592713 B CN109592713 B CN 109592713B
Authority
CN
China
Prior art keywords
preparation
semiconductor material
gas sensor
tungsten trioxide
tungsten
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
Application number
CN201910006199.1A
Other languages
Chinese (zh)
Other versions
CN109592713A (en
Inventor
朱永恒
蔡海洁
付元帅
刘海泉
赵勇
鄂畅
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shanghai Ocean University
Original Assignee
Shanghai Ocean University
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Shanghai Ocean University filed Critical Shanghai Ocean University
Priority to CN201910006199.1A priority Critical patent/CN109592713B/en
Publication of CN109592713A publication Critical patent/CN109592713A/en
Application granted granted Critical
Publication of CN109592713B publication Critical patent/CN109592713B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G41/00—Compounds of tungsten
    • C01G41/02—Oxides; Hydroxides
    • 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
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
    • G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
    • G01N27/12—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a solid body in dependence upon absorption of a fluid; of a solid body in dependence upon reaction with a fluid, for detecting components in the fluid
    • G01N27/125—Composition of the body, e.g. the composition of its sensitive layer
    • G01N27/127—Composition of the body, e.g. the composition of its sensitive layer comprising nanoparticles
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
    • C01P2002/72—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by d-values or two theta-values, e.g. as X-ray diagram
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/01—Particle morphology depicted by an image
    • C01P2004/03—Particle morphology depicted by an image obtained by SEM
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/01—Particle morphology depicted by an image
    • C01P2004/04—Particle morphology depicted by an image obtained by TEM, STEM, STM or AFM
    • 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
    • C01P2004/32—Spheres
    • C01P2004/34—Spheres hollow
    • 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

Abstract

The invention provides a preparation method of a tungsten trioxide hollow nanosphere semiconductor material, belonging to the technical field of semiconductor materials, and the preparation method comprises the steps of mixing a soluble hexavalent tungsten salt, an alcohol-water solvent and an alkaline precipitator, and carrying out hydrothermal reaction on the obtained mixed solution to obtain the tungsten trioxide hollow nanosphere semiconductor material; the concentration of the hexavalent tungsten salt in the mixed solution is 5-30 mmol/L, and the concentration of the precipitator is 0.1-0.5 mol/L; the temperature of the hydrothermal reaction is 100-200 ℃, and the time of the hydrothermal reaction is 5-40 h. The tungsten oxide hollow nanosphere semiconductor material with uniform particle size, complete crystal grains and uniform wall thickness is obtained by controlling the proportion of reaction raw materials, the reaction temperature and the reaction time. The invention also provides a gas sensor prepared from the tungsten trioxide hollow nanosphere semiconductor material, and the gas sensor is applied to detection of organophosphorus pesticides and has high sensitivity.

Description

Tungsten trioxide hollow nanosphere semiconductor material and preparation method thereof, gas sensor and preparation method and application thereof
Technical Field
The invention relates to the technical field of semiconductor materials, in particular to a tungsten trioxide hollow nanosphere semiconductor material and a preparation method thereof, and a gas sensor and a preparation method and application thereof.
Background
The food safety is related to public health problems such as human health and the like, and is mainly caused by the overproof residual toxic and harmful substances in food. In recent years, due to the pollution of planting environment, the aggravation of plant diseases and insect pests, the increase of market demand, the lack of pesticide-related professional knowledge for pesticide users and the like, the phenomenon of pesticide abuse or unreasonable use is serious, so that the pesticide residue problem becomes one of the main sources of food safety problems. The organophosphorus pesticide is the pesticide with the most extensive application and the largest use amount in the production process of agricultural products in China at present. However, most organophosphorus pesticides belong to highly toxic or highly toxic pesticides, have strong inhibitory action on cholinesterase in human bodies, easily enter human bodies through mucous membranes, digestive tracts, respiratory tracts, oral cavities and the like, invade the digestive system, the circulatory system and the nervous system of the human bodies, damage the heart, the liver, the kidney and other functional organs of poisoned people, and seriously affect the health of the human bodies when foods with overproof organophosphorus pesticide residues are taken. Organophosphorus pesticides are of a wide variety, and representative organophosphorus pesticides are: acephate, dichlorvos, parathion, methyl parathion and the like. At present, common detection methods for organophosphorus pesticide residues mainly comprise: chromatography, mass spectrometry, and a combination of chromatography and mass spectrometry. However, these methods have high requirements for professional knowledge and literacy of inspectors, are time-consuming and labor-consuming, have complex test result analysis methods, involve expensive experimental equipment and have low analysis real-time performance, are mostly only suitable for laboratory detection, and are difficult to realize real-time field detection. Therefore, in the face of the increasingly severe pesticide residue problem, it is important to research a method which is accurate, reliable, effective, convenient and quick and is suitable for on-site pesticide residue detection.
In recent years, a semiconductor metal oxide sensor has been widely used in the fields of industrial production, environmental monitoring, human life, and the like as a semiconductor sensor that is simple to manufacture, low in cost, and long in service life. WO3The nano material has a series of novel optical, thermal, electric, acoustic and magnetic properties due to quantum size effect, small size effect, surface effect and macroscopic quantum tunneling effect, and is widely researched and applied to the research aspect of sensitive materials of semiconductor sensors. In the prior art, preparation of WO3The methods for preparing the hollow spherical structure material include template method, sol-gel method and the like, but the methods all need to introduce a large amount of strong acid and includeOrganic solvent, high cost, easy environmental pollution, and the prepared WO3The shape of the hollow spherical structural material is unstable.
Disclosure of Invention
In view of the above, the invention aims to provide a tungsten trioxide hollow nanosphere semiconductor material, a preparation method thereof, a gas sensor and a preparation method thereof.
The invention provides a preparation method of a tungsten trioxide hollow nanosphere semiconductor material, which comprises the following steps:
mixing soluble hexavalent tungsten salt, an alcohol-water solvent and an alkaline precipitator, and carrying out hydrothermal reaction on the obtained mixed solution to obtain a tungsten trioxide nano hollow sphere semiconductor material;
the concentration of the hexavalent tungsten salt in the mixed solution is 5-30 mmol/L, and the concentration of the alkaline precipitator is 0.1-0.5 mol/L;
the temperature of the hydrothermal reaction is 100-200 ℃, and the time of the hydrothermal reaction is 5-40 h.
Preferably, the water-soluble hexavalent tungsten salt is WCl6、Na2WO4·2H2O or Na2WO4。
Preferably, the alcohol-water solvent is a mixture of a small molecular alcohol solvent and water, and the volume ratio of the small molecular alcohol solvent to the water is 30-50: 100.
preferably, the small molecular alcohol solvent comprises one or more of methanol, ethanol and propanol.
Preferably, the alkaline precipitant is urea, thiourea or ammonia.
The invention also provides the tungsten trioxide hollow nanosphere semiconductor material prepared by the preparation method, wherein the particle size of the tungsten trioxide hollow nanosphere is 350-500nm, and the wall thickness is 20-40 nm.
The invention also provides a preparation method of the gas sensor, which comprises the following steps:
1) mixing the tungsten trioxide hollow nanosphere semiconductor material with an adhesive, and coating the obtained paste on the outer surface of the ceramic tube to obtain the ceramic tube with the wet coating; the tungsten trioxide hollow nanosphere semiconductor material is prepared by the preparation method;
2) drying and calcining the ceramic tube with the wet coating in the step 1) in sequence to obtain a ceramic tube with a dry coating;
3) welding 4 electrode wires of the ceramic tube with the dry coating in the step 2) on the base, penetrating a heating wire through the ceramic tube with the dry coating, welding two ends of the heating wire on the base, and aging the obtained element to obtain the gas sensor.
Preferably, the calcining temperature in the step 2) is 250-350 ℃, and the calcining time is 2-5 h.
The invention also provides the gas sensor prepared by the preparation method.
The invention also provides application of the gas sensor prepared by the preparation method in the aspect of detecting organophosphorus pesticides.
The beneficial technical effects are as follows: the invention provides a preparation method of a tungsten trioxide hollow nanosphere semiconductor material, which comprises the steps of mixing a soluble hexavalent tungsten salt, an alcohol-water solvent and an alkaline precipitator, and carrying out hydrothermal reaction on the obtained mixed solution to obtain the tungsten trioxide hollow nanosphere semiconductor material; the concentration of the hexavalent tungsten salt in the mixed solution is 5-30 mmol/L, and the concentration of the alkaline precipitator is 0.1-0.5 mol/L; the temperature of the hydrothermal reaction is 100-200 ℃, and the time of the hydrothermal reaction is 5-40 h. The tungsten oxide hollow nanosphere semiconductor material with uniform particle size, complete crystal grains and uniform wall thickness can be obtained by controlling the proportion of reaction raw materials, the reaction temperature and the reaction time.
The invention also provides a gas sensor prepared from the tungsten trioxide hollow nanosphere semiconductor material, and the gas sensor is applied to detection of organophosphorus pesticides and has high sensitivity.
Description of the drawings:
FIG. 1 shows WO prepared in example 23The X-ray diffraction pattern of the hollow sphere nano material;
FIG. 2 shows WO prepared in examples 1 to 33SEM photograph of scanning electron microscope of the hollow nano-sphere semiconductor material;
FIG. 3 shows WO prepared in examples 1 to 33TEM picture of nanometer hollow sphere semiconductor material transmission electron microscope;
FIG. 4 is a graph showing the relationship between the voltage of the gas sensor obtained in example 6 and the concentration of acephate;
FIG. 5 is a response recovery curve of the resulting gas sensor prepared in example 6;
FIG. 6 shows a diagram of example 7 based on WO3Response graphs of the nano hollow sphere sensor to different substances;
FIG. 7 is an SEM photograph of the WO3 hollow nanosphere semiconductor material obtained in example 4 under a scanning electron microscope;
fig. 8 is an SEM photograph of the WO3 hollow nanosphere semiconductor material obtained in example 5 under a scanning electron microscope.
Detailed Description
The invention provides a preparation method of a tungsten trioxide hollow nanosphere semiconductor material, which comprises the following steps:
mixing soluble hexavalent tungsten salt, an alcohol-water solvent and an alkaline precipitator, and carrying out hydrothermal reaction on the obtained mixed solution to obtain a tungsten trioxide nano hollow sphere semiconductor material;
the concentration of the hexavalent tungsten salt in the mixed solution is 5-30 mmol/L, and the concentration of the alkaline precipitator is 0.1-0.5 mol/L;
the temperature of the hydrothermal reaction is 100-200 ℃, and the time of the hydrothermal reaction is 5-40 h.
In the present invention, the water-soluble hexavalent tungsten salt is preferably WCl6、Na2WO4·2H2O or Na2WO4。
In the invention, the alcohol-water solvent is preferably a mixture of a small molecular alcohol solvent and water, and the volume ratio of the small molecular alcohol solvent to the water is preferably 30-50: 100, and more preferably 35-45: 100.
In the present invention, the small molecule alcohol solvent preferably includes one or more of methanol, ethanol and propanol, and more preferably ethanol. When the small molecular alcohol solvent is two or more small molecular alcohols, the dosage ratio of the small molecular alcohols is not specially limited, and the small molecular alcohols can be mixed in any proportion.
In the present invention, the alkaline precipitant is preferably urea, thiourea or aqueous ammonia.
In the present invention, the method of mixing the soluble hexavalent tungsten salt, the alcohol-water solvent and the alkaline precipitant is preferably to mix the soluble hexavalent tungsten salt and the alcohol-water solvent, stir the mixture, and then add the alkaline precipitant.
In the invention, the stirring time is preferably 5-10 min, and the stirring method is not particularly limited, and can be a stirring method well known to those skilled in the art. The invention makes the soluble hexavalent tungsten salt completely dissolved in the alcohol-water solvent by stirring.
In the invention, the concentration of the hexavalent tungsten salt in the mixed solution is 5-30 mmol/L, preferably 10-25 mmol/L, and more preferably 15-20 mmol/L; the concentration of the alkaline precipitant in the mixed solution is 0.1-0.5 mol/L, preferably 0.2-0.3 mol/L. In the invention, as the concentration of reactants is increased, the uniformity of hollow sphere particles is increased, and the particle size and the wall thickness are increased.
In the invention, the temperature of the hydrothermal reaction is 100-200 ℃, is selected to be 100-150 ℃, and is more preferably 110-130 ℃; the time of the hydrothermal reaction is 5-40 h, preferably 10-30 h, and more preferably 15-20 h. In the invention, the hydrothermal reaction temperature is too high, the obtained product is easy to agglomerate, and the product obtained by too low reaction temperature is difficult to form a hollow structure; with the increase of the hydrothermal reaction time, the particle size of the obtained tungsten trioxide hollow nanospheres is not changed significantly, but the shell thickness is reduced, and the particle uniformity is poor.
In the invention, after the hydrothermal reaction, the method preferably further comprises the steps of sequentially cooling the obtained reaction liquid to room temperature, centrifuging, washing and drying to obtain the tungsten trioxide hollow nanosphere semiconductor material.
The rate of cooling to room temperature is not particularly limited in the present invention, and may be selected from rates well known to those skilled in the art; the method of centrifugation in the present invention is not particularly limited, and a centrifugation method known to those skilled in the art may be selected to separate solid from liquid.
In the present invention, the washing is preferably performed by sequentially subjecting the solid product obtained after centrifugation to ethanol washing and water washing. The method of washing with ethanol and water in the present invention is not particularly limited, and a washing method known to those skilled in the art may be used.
In the present invention, the drying is preferably performed on the solid product obtained after the washing. In the invention, the drying temperature is preferably 50-100 ℃, and more preferably 70-80 ℃; the drying time is preferably 12-20 hours, and more preferably 16-18 hours.
The invention provides a tungsten trioxide hollow nanosphere semiconductor material prepared by the preparation method, wherein the particle size of the tungsten trioxide hollow nanosphere is 350-500nm, and the wall thickness is 20-40 nm.
The invention also provides a preparation method of the gas sensor, which comprises the following steps:
1) mixing the tungsten trioxide hollow nanosphere semiconductor material with an adhesive, and coating the obtained paste on the outer surface of the ceramic tube to obtain the ceramic tube with the wet coating; the tungsten trioxide hollow nanosphere semiconductor material is prepared by the preparation method;
2) drying and calcining the ceramic tube with the wet coating in the step 1) in sequence to obtain a ceramic tube with a dry coating;
3) welding 4 electrode wires of the ceramic tube with the dry coating in the step 2) on the base, penetrating a heating wire through the ceramic tube with the dry coating, welding two ends of the heating wire on the base, and aging the obtained element to obtain the gas sensor.
Mixing tungsten trioxide hollow nanosphere semiconductor material with an adhesive, and coating the obtained paste on the outer surface of a ceramic tube to obtain the ceramic tube with a wet coating; the tungsten trioxide hollow nanosphere semiconductor material is the tungsten trioxide hollow nanosphere semiconductor material or the tungsten oxide hollow nanosphere semiconductor material prepared by the preparation method of any one of claims 2-6.
In the invention, the tungsten trioxide hollow nanosphere semiconductor material is preferably ground. The method of polishing in the present invention is not particularly limited, and polishing methods known to those skilled in the art may be used. In the present invention, it is preferable to perform the polishing in an agate mortar, and the polishing time is not particularly limited in the present invention, and the tungsten trioxide hollow nanosphere semiconductor material may be uniformly dispersed.
In the present invention, the binder is preferably water, terpineol, carboxymethyl cellulose, more preferably water; the dosage of the adhesive is preferably 10-50% of the mass of the tungsten trioxide hollow nanosphere semiconductor material, and more preferably 25%. The method for mixing the tungsten trioxide hollow nanosphere semiconductor material and the adhesive is not particularly limited, and the mixing method known by the person skilled in the art can be selected.
In the present invention, the ceramic tube is preferably a ceramic tube with a Pt lead and an Au electrode.
In the present invention, the coating thickness of the paste on the outer surface of the ceramic tube is not particularly limited, and any coating thickness known to those skilled in the art may be selected.
After the ceramic tube with the wet coating is obtained, the ceramic tube with the wet coating is sequentially dried and calcined to obtain the ceramic tube with the dry coating.
In the present invention, the drying is preferably infrared drying. Particularly preferably, the ceramic tube with the wet coating is dried in the ceramic square boat under an infrared lamp.
In the invention, the calcination temperature is preferably 250-350 ℃, more preferably 300-320 ℃, and the calcination time is preferably 2-5 h, more preferably 3-4 h. The invention removes the adhesive by calcining and leads the material to be tightly coated on the surface of the ceramic tube to form a compact material coating.
After the ceramic tube with the dry coating is obtained, 4 electrode wires of the ceramic tube with the dry coating are welded on the base, the heating wire penetrates through the ceramic tube with the dry coating, two ends of the heating wire are welded on the base, and the obtained element is aged to obtain the gas sensor.
In the invention, the base is preferably a gas-sensitive test plate matching base; the aging time is preferably 3 to 10 days, and more preferably 5 to 7 days.
The invention also provides the gas sensor prepared by the preparation method.
The invention also provides application of the gas sensor prepared by the preparation method in the aspect of detecting organophosphorus pesticides.
In the present invention, the organophosphorus pesticide is preferably acephate, dichlorvos, dimethoate or parathion, and more preferably acephate.
In order to better understand the present invention, the following examples are further provided to illustrate the present invention, but the present invention is not limited to the following examples.
Example 1:
0.72mmol of WCl660mL ethanol-water (V) was addedEthanol/VWater (W): 30%) in solution. Stirring for 5min on a magnetic stirrer to obtain a slightly white semitransparent solution; then, the mixture was transferred to a 100mL stainless steel reactor lined with Teflon, and 0.1g urea was added to the reactor to obtain a mixed solution. WCl in the obtained mixed solution6The concentration of (2) was 12 mmol/L.
Placing the reaction kettle in an electric oven at 120 ℃ for hydrothermal reaction for 24 hours, and naturally cooling to room temperature; the white product was collected by centrifugation and washed with deionized ethanol and deionized water, respectively, and then dried at 80 ℃ overnight to give WO3The hollow nanosphere is made of a semiconductor material.
Example 2:
WCl in the obtained mixed solution6Has a concentration of 16mmol/L, and othersThe same conditions as in example 1 were used.
Example 3
WCl in the obtained mixed solution6The concentration of (2) was 20mmol/L, and the other conditions were the same as those in example 1.
FIG. 1 shows WO prepared in example 23The X-ray diffraction pattern of the hollow sphere nano material, all XRD diffraction peaks marked in the pattern and a standard pattern (JCPDS No.46-1096,
Figure BDA0001935531890000071
) The peaks of (A) being completely in phase with WO belonging to the cubic phase3No other impurity peaks are evident in the figure, indicating that the sample is a single WO3And (4) phase(s).
FIG. 2 shows WO prepared in examples 1 to 33SEM photos of scanning electron microscope of hollow nanosphere semiconductor material, wherein 2a, 2b and 2c are WO obtained in example 1, example 2 and example 3 respectively3SEM photograph of scanning electron microscope of the hollow nanosphere semiconductor material. As can be seen from FIG. 2, with WCl6The concentration of (a) is increased in turn,
FIG. 3 shows WO prepared in examples 1 to 33TEM picture of nanometer hollow sphere semiconductor material transmission electron microscope; wherein 3a, 3b, 3c are WO obtained in example 1, example 2 and example 3, respectively3TEM image of transmission electron microscope of hollow nano-ball semiconductor material.
As can be seen from FIGS. 2 and 3, when WCl is used6At a concentration of 16mmol/L, WO synthesized3The nano materials all have hollow spherical regular shapes, the sizes of crystal grains are consistent, and the wall thickness is uniform. Thus, by controlling WCl6Can control the concentration of WO3The shape, the grain size distribution and the wall thickness distribution of the hollow nanospheres.
Example 4
The temperature of the hydrothermal reaction was 150 ℃. The rest is the same as in example 2. FIG. 7 shows WO obtained in example 43SEM photograph of scanning electron microscope of hollow nanosphere semiconductor material, and it can be seen from FIG. 7 that the hydrothermal reaction temperature is 150 deg.CWO3The particle size uniformity of the hollow nanospheres is reduced compared with that of example 2, and slight agglomeration phenomenon occurs.
Example 5
The hydrothermal reaction time was 36 h. The rest is the same as in example 2. FIG. 8 shows WO obtained in example 53SEM photograph of scanning electron microscope of hollow nanosphere semiconductor material, and it can be seen from FIG. 8 that the WO synthesized when the hydrothermal reaction time was 36h3The uniformity of the nano hollow sphere nano particles is reduced, and partial spherical shell fracture occurs.
Example 6
Placing the WO prepared in example 1 in an agate mortar3100mg of hollow nanosphere semiconductor material, grinding uniformly, dripping 50mg of adhesive, mixing into paste, uniformly coating on the outside of ceramic tube with bamboo stick, and coating WO3The ceramic tube made of the hollow nano-sphere semiconductor material is placed in a ceramic square boat, dried under an infrared lamp, calcined in a muffle furnace at 300 ℃ for 3 hours to remove the adhesive used in the material, and naturally cooled for later use. Welding 4 electrode wires of the ceramic tube obtained after calcination on a base, then penetrating a heating wire through the ceramic tube and welding two ends of the heating wire on the base to manufacture a gas sensor, placing the gas sensor on a special aging table, and aging for 240h to obtain the gas sensor.
Fig. 4 is a graph showing the relationship between the voltage of the gas sensor obtained in this embodiment and the concentration of acephate. As can be seen from fig. 4, the voltage of the gas sensor obtained in this embodiment increases with the increase of the acephate concentration, and is in a linear relationship.
FIG. 5 is a response recovery curve of the gas sensor prepared in this example. Defining a response time tresAfter the element contacts the gas to be measured, the load resistance RLVoltage on by U0Change to U0+90％(UX-U0) Time required, recovery time trevAfter the gas sensor is separated from the gas to be measured, the load resistor RLVoltage of by UXIs restored to U0+10％(UX-U0) The time taken. As can be seen from FIG. 5, the gas sensor obtained in this exampleThe device has better response to 1ppm of acephate and short response-recovery time which is respectively 13s and 10 s.
Example 7
Using WO prepared in example 63The hollow nanosphere sensor is used for detecting four common organophosphorus pesticides, and the process and the steps are as follows:
WO prepared in example 6 on a HW-30A gas sensor test system by adopting a static gas distribution method3And (5) carrying out gas sensor performance test on the hollow nanosphere sensor. The main technical parameters of the test system are as follows: the number of test channels: 30 routes of the solution; collecting speed, 1 time/s; 1% of system comprehensive error; power supply, 220V, 50 Hz; heating voltage Vh, 5V; loop voltage Vc, 5V; a load resistance RL. By testing the load resistance R in series with the gas-sensitive elementLThe voltage Vout on the substrate reflects the characteristics of the gas sensor. At the optimal working temperature of 290 ℃, gas-sensitive tests are respectively carried out on dichlorvos, acephate, methyl parathion, isopropanol, formaldehyde, acetone and ammonia gas with the concentration of 25ppm to a test system.
FIG. 6 shows a WO-based alloy prepared in this example3The nanometer hollow sphere sensor has response diagrams of eight substances, namely acephate, dichlorvos, dimethoate, parathion, isopropanol, formaldehyde, acetone and ammonia gas, wherein the dichlorvos, the dimethoate, the parathion and the acephate are four common organophosphorus pesticides at present. The sensitivity of the element is defined as Ra/Rg, and Ra and Rg are the voltage values of the element in air and gas to be measured respectively. As can be seen from FIG. 6, under the condition that the working temperature is 290 ℃, the gas sensor has better response to organophosphorus pesticides than other toxic and harmful gases, wherein the response to acephate is the best, which indicates that the selectivity of the gas sensor to acephate is strong.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims (8)

1. A preparation method of a tungsten trioxide hollow nanosphere semiconductor material comprises the following steps:
mixing soluble hexavalent tungsten salt, an alcohol-water solvent and an alkaline precipitator, and carrying out hydrothermal reaction on the obtained mixed solution to obtain a tungsten trioxide nano hollow sphere semiconductor material;
the concentration of the hexavalent tungsten salt in the mixed solution is 5-30 mmol/L, and the concentration of the alkaline precipitator is 0.1-0.5 mol/L;
the temperature of the hydrothermal reaction is 100-150 ℃, and the time of the hydrothermal reaction is 5-40 h;
the soluble hexavalent tungsten salt is WCl6(ii) a The alkaline precipitator is thiourea or ammonia water.
2. The preparation method according to claim 1, wherein the alcohol-water solvent is a mixture of a small molecular alcohol solvent and water, and the volume ratio of the small molecular alcohol solvent to the water is 30-50: 100.
3. the method of claim 2, wherein the small molecule alcohol solvent comprises one or more of methanol, ethanol, and propanol.
4. The tungsten oxide hollow nanospheres prepared by the preparation method of any one of claims 1 to 3, wherein the tungsten trioxide hollow nanospheres have a particle size of 350 to 500nm and a wall thickness of 20 to 40 nm.
5. A method of making a gas sensor, comprising the steps of:
1) mixing the tungsten trioxide hollow nanosphere semiconductor material with an adhesive, and coating the obtained paste on the outer surface of the ceramic tube to obtain the ceramic tube with the wet coating; the tungsten trioxide hollow nanosphere semiconductor material is prepared by the preparation method of any one of claims 1-3;
2) drying and calcining the ceramic tube with the wet coating in the step 1) in sequence to obtain a ceramic tube with a dry coating;
3) welding 4 electrode wires of the ceramic tube with the dry coating in the step 2) on the base, penetrating a heating wire through the ceramic tube with the dry coating, welding two ends of the heating wire on the base, and aging the obtained element to obtain the gas sensor.
6. The preparation method of claim 5, wherein the calcining temperature in the step 2) is 250-350 ℃, and the calcining time is 2-5 h.
7. The gas sensor prepared by the preparation method of any one of claims 5 to 6.
8. The application of the gas sensor prepared by the preparation method of any one of claims 5 to 6 in the detection of organophosphorus pesticides.
CN201910006199.1A 2019-01-04 2019-01-04 Tungsten trioxide hollow nanosphere semiconductor material and preparation method thereof, gas sensor and preparation method and application thereof Expired - Fee Related CN109592713B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910006199.1A CN109592713B (en) 2019-01-04 2019-01-04 Tungsten trioxide hollow nanosphere semiconductor material and preparation method thereof, gas sensor and preparation method and application thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910006199.1A CN109592713B (en) 2019-01-04 2019-01-04 Tungsten trioxide hollow nanosphere semiconductor material and preparation method thereof, gas sensor and preparation method and application thereof

Publications (2)

Publication Number Publication Date
CN109592713A CN109592713A (en) 2019-04-09
CN109592713B true CN109592713B (en) 2021-01-29

Family

ID=65965023

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910006199.1A Expired - Fee Related CN109592713B (en) 2019-01-04 2019-01-04 Tungsten trioxide hollow nanosphere semiconductor material and preparation method thereof, gas sensor and preparation method and application thereof

Country Status (1)

Country Link
CN (1) CN109592713B (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110672671B (en) * 2019-10-18 2022-04-01 上海理工大学 Acetone sensitive material and sensitive element and preparation method thereof
CN115128134A (en) * 2022-06-21 2022-09-30 武汉铂纳智感科技有限公司 Gas sensor based on optical excitation, preparation method and application

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104458827A (en) * 2014-12-15 2015-03-25 吉林大学 NO2 gas sensor based on hollow spherical WO3 and preparation method of NO2 gas sensor based on the hollow spherical WO3
CN107561133A (en) * 2017-08-28 2018-01-09 东北大学 A kind of preparation method and application of precious metal doping WO3 base formaldehyde gas sensitive materials

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104458827A (en) * 2014-12-15 2015-03-25 吉林大学 NO2 gas sensor based on hollow spherical WO3 and preparation method of NO2 gas sensor based on the hollow spherical WO3
CN107561133A (en) * 2017-08-28 2018-01-09 东北大学 A kind of preparation method and application of precious metal doping WO3 base formaldehyde gas sensitive materials

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
Template-free hydrothermal synthesis of 3D hollow aggregate spherical structure WO3 nano-plates and photocatalytic properties;Yang Zhao等;《Materials Research Bulletin》;20180202;280-286 *
Template-free to fabricate highly sensitive and selective acetone gas sensor based on WO3 microspheres;Yidong Zhang等;《Vacuum》;20130219;第31页2. Experimental section以及第32页左栏第1段 *

Also Published As

Publication number Publication date
CN109592713A (en) 2019-04-09

Similar Documents

Publication Publication Date Title
CN106124573B (en) A kind of acetone gas sensor and preparation method thereof based on NiO/ZnO heterojunction structure hollow sphere sensitive material
CN107561133B (en) A kind of preparation method and application of precious metal doping WO3 base formaldehyde gas sensitive material
CN106770497B (en) One kind being based on Pt/ α-Fe2O3The acetone gas sensor and preparation method thereof of porous nanoparticles sensitive material
Li et al. Two-step solid-state synthesis of tin oxide and its gas-sensing property
WO2018082585A1 (en) Synthesis method for composite gas sensitive material of porous zinc oxide nanosheet loaded with a high-dispersion nano precious metal
CN109592713B (en) Tungsten trioxide hollow nanosphere semiconductor material and preparation method thereof, gas sensor and preparation method and application thereof
CN106365204B (en) Preparation method for the tungstic acid sensitive material of ammonia gas sensor
CN109796038A (en) A kind of preparation method and its Application in Sensing of classifying nano porous oxidation copper product
CN105699439B (en) A kind of preparation method and application of the methanol gas sensor based on carbonitride carried metal and metal oxide composite
CN108732214A (en) Based on PdO@In2O3The acetone gas sensor and preparation method thereof of compound nano sensitive material
CN104950017A (en) Gas sensor based on core-shell flower-ball-shaped ZnFe2O4 nanometer materials, preparing method and application thereof
CN110398520A (en) A kind of Pr doping In2O3The preparation method of gas-sensitive nano material
CN109946358A (en) One kind is with MTiO3Electric potential type SO is blended together for the YSZ base of sensitive electrode2Sensor, preparation method and applications
CN109678214B (en) Acetone-sensitive cobaltosic oxide/indium oxide nanotube composite film
CN111060560A (en) Ru-WO3 nano material and preparation method and application thereof
CN110749628A (en) Acetone-sensitive cobaltosic oxide/zinc oxide nano-meter rice heterojunction thin film
CN108956708A (en) A kind of alcohol gas sensor and preparation method thereof based on zinc ferrite nano sensitive material
CN105784775B (en) A kind of preparation method of ethyl acetate gas sensitive material
CN107449805B (en) Acetone-sensitive zinc cobaltate nano multi-shell yolk-shell membrane
CN106896146B (en) A kind of coating production of zinc ferrite acetone gas sensing layer
CN111307880B (en) Preparation method of organic volatile gas sensor based on MOF core-shell nanostructure
CN108776156A (en) One-dimensional α-Fe2O3The preparation method of nanometer rods and be based on α-Fe2O3The acetone sensor of nanometer rods
CN109521064B (en) Room temperature NO2 sensor based on WO3 hollow sphere and preparation method thereof
CN110702752A (en) Manufacturing method of gas sensor for ammonia gas detection
CN110161091B (en) Gas sensing module and preparation method and application thereof

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: 20210129

Termination date: 20220104

CF01 Termination of patent right due to non-payment of annual fee