CN109911929B - SnO prepared by taking Pt as catalyst2Method and application of nano material - Google Patents
SnO prepared by taking Pt as catalyst2Method and application of nano material Download PDFInfo
- Publication number
- CN109911929B CN109911929B CN201910253135.1A CN201910253135A CN109911929B CN 109911929 B CN109911929 B CN 109911929B CN 201910253135 A CN201910253135 A CN 201910253135A CN 109911929 B CN109911929 B CN 109911929B
- Authority
- CN
- China
- Prior art keywords
- sno
- nano material
- gas
- ceramic substrate
- porous ceramic
- 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.)
- Active
Links
Images
Landscapes
- Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)
Abstract
SnO prepared by taking Pt as catalyst2A method and application of nano material belongs to the field of gas sensor of metal oxide semiconductor material. SnO prepared by taking Pt as catalyst2Nanomaterial of said SnO2The nano material is in a comb-shaped structure, and nanowires densely grow around the surface of the trunk; the nano material is SnO with a rutile tetragonal phase crystal structure2Forming; the diameter of the trunk is 100-500 nm, the length is 100-500 μm, the diameter of the nanowire is 80-200 nm, and the length is 400 nm-2 μm. Invention H2S gas sensor obtains H pairs at lower working temperature2The S gas has the maximum sensitivity, quick response and recovery speed, the lower detection limit is 500ppb, and the detection is for H2S has excellent selectivity. The invention overcomes the defects of the prior H2The S gas sensor has the defects of overhigh working temperature, low response recovery speed, poor selectivity and the like, and has good application prospect.
Description
Technical Field
The invention belongs to the technical field of gas sensors made of metal oxide semiconductor materials, and particularly relates to a method for preparing SnO (stannic oxide) by taking Pt as a catalyst2Methods and applications of nanomaterials.
Background
The exploitation and utilization of mineral resources always occupy irreplaceable positions in the economic development of China. However, the safe production condition of the mining industry in China is always not optimistic, and mines in various places are safeAll events happen occasionally, and especially hydrogen sulfide (H) is caused by a highly toxic gas in sulfur-containing mines in China2S) accidents caused by gushing. Thus, for H2Effective monitoring and timely early warning of S gas become a bottleneck problem which needs to be solved urgently in mines in China.
A gas sensor is a component or device that converts the detected gas components and concentrations into signals that are more easily recognized by a human (e.g., electrical, acoustic, optical, digital, etc.). Most of the existing gas sensors for monitoring hydrogen sulfide are electrochemical or semiconductor type sensors, but the electrochemical sensors generally have the problems of high price, short service life and the like. The semiconductor sensor is expected to be used for detecting H in mine safety production by the characteristics of high sensitivity, long service life, low power consumption, low cost, easy miniaturization and integration2S, high-efficiency sensor. Metal oxide semiconductor material SnO2Is the most widely used gas-sensitive material at present and is used for H2S also has a good response. Currently prepared SnO2The method comprises a hydrothermal method, a sol-gel method, a chemical precipitation method and the like, wherein the low-dimensional SnO prepared based on a thermal evaporation method2The nano material has huge specific surface area and excellent length-diameter ratio; meanwhile, the low-dimensional nano material is easy to form a latticed sensitive layer, and the abundant loose porous structure of the low-dimensional nano material is very beneficial to H2The S gas rapidly permeates into the whole sensitive layer, so that the response/recovery time of the sensitive layer is obviously improved, and the nano nodes formed by lapping among a large number of low-dimensional nano materials are also beneficial to improving the sensitivity of the material to the target gas. However, the current thermal evaporation method has the defects of low yield, difficult control of process parameters and the like. In the process of preparing the low-dimensional nano material, the pressure in the furnace, the position and the type of a growth substrate and the like are generally required to be controlled; in addition, in the thermal evaporation method, a small amount of oxygen needs to be mixed into argon, and residual oxygen in the argon in a furnace is used, so that the repeatability of the morphology of the obtained product is generally poor. According to the studies published in the Journal of the American chemical society (Journal of Physical Chemistry C, 2018, 122, 24407-24414), it is shown that the preparation of SnO by thermal evaporation based on the "gas-liquid-solid" growth mechanism2Nano meterToo much or too little oxygen supply during the material process inhibits its growth. Therefore, the control of the amount of oxygen is one of the key influencing factors in the thermal evaporation method, and the amount of oxygen also influences the structure and application of the final product. Therefore, there is a need for a simple method for efficiently preparing low-dimensional SnO using a porous ceramic substrate having more surface binding sites in a normal pressure environment and easily controlling the flow of oxygen during thermal evaporation2Nanomaterials and for H2S gas sensor.
Disclosure of Invention
The invention aims to provide a method for preparing SnO by using metal Pt as a catalyst and adopting a thermal evaporation method2A method of nano material to realize that metal Pt is used as a catalyst to promote SnO2The formation of nano material structure can be used as dopant to raise H pair2Gas-sensitive properties of S gas. The method has the advantages of easy control of oxygen flow, simple operation and high repeatability in a normal pressure environment.
SnO prepared by taking Pt as catalyst2Nanomaterial of said SnO2The nano material is in a comb-shaped structure, and nanowires densely grow around the surface of the trunk; the nano material is SnO with a rutile tetragonal phase crystal structure2Forming; the diameter of the trunk is 100-500 nm, the length of the trunk is 100-500 mu m, the diameter of the nanowire is 80-200 nm, and the length of the nanowire is 400 nm-2 mu m.
The comb-shaped structure is a structure that a plurality of nanowires are distributed on a main stem and form a comb shape.
Another purpose of the invention is to provide a method for preparing SnO by taking Pt as a catalyst2A method of nanomaterials, the method comprising:
sputtering a layer of Pt film on the surface of a porous ceramic substrate by a direct current sputtering instrument, wherein the sputtering current is 4-12 mA, and the sputtering time is 45-60 s;
placing 0.2-0.5 g of Sn particles with the purity of 99.99% in the middle of an alumina ceramic boat, placing the side of the porous ceramic substrate plated with the Pt film facing the Sn particles at an angle of 30-60 degrees with the direction of an air inlet, sending the ceramic boat into a central heating area of a quartz tube of a tube furnace, and installing a flange for sealing;
thirdly, argon with the purity of 99.99 percent is introduced into the tube furnace at the flow rate of 200-300 ml/min for 20min, then the flow rate of the argon is adjusted to 50-100 ml/min, meanwhile, a heating device is started, the temperature is increased to 900-1000 ℃ at the temperature increase rate of 5-10 ℃/min, and the temperature is kept for 60-90 min; when the temperature of the tube furnace rises to 200-300 ℃, introducing oxygen with the purity of 99.99% into the tube furnace; the flow of the oxygen is controlled by a needle valve with scales, and the opening degree of the needle valve is 2-5 circles;
fourthly, after the tube furnace is naturally cooled to the room temperature, argon and oxygen are closed, the alumina porcelain boat is taken out, the white flocculent product is scraped from the surface of the porous ceramic substrate, and the white flocculent product is SnO prepared by taking Pt as a catalyst2And (3) nano materials.
Preferably, the porous ceramic substrate is made of diatomite or kaolin containing aluminosilicate components, and is subjected to porous treatment by adopting a pore-forming agent pore-forming method, wherein the pore-forming agent is spherical graphite or PMMA microspheres, the average diameter of the pore-forming agent is 10-70 μm, the addition ratio is 20-50 wt.%, and the porous ceramic substrate is formed by adopting a mould pressing sintering method, and the sintering temperature is 1000-1200 ℃.
Preferably, the length of the porous ceramic substrate is 15-20 mm, the width is 5-10 mm, and the thickness is 1-2 mm.
Another object of the present invention is to provide a SnO2H with nano material as sensitive layer2S gas sensor, which is made of SnO2The nano material is a gas-sensitive material, the gas-sensitive material is uniformly coated on the surface of an electrode element, and the electrode element is a planar electrode.
SnO prepared by taking Pt as catalyst2Nanomaterial of said SnO2The nano material is in a comb-shaped structure, and nanowires densely grow around the surface of the trunk; the nano material is SnO with a rutile tetragonal phase crystal structure2Forming; the diameter of the trunk is 100-500 nm, the length of the trunk is 100-500 mu m, the diameter of the nanowire is 80-200 nm, and the length of the nanowire is 400 nm-2 mu m.
According to the inventionIt is still another object to provide a method of producing the following2The preparation method of the S gas sensor comprises the following steps:
first, the following SnO2Pouring the nano material into a 2ml conical centrifuge tube filled with 0.5ml absolute ethyl alcohol, and uniformly dispersing in an ultrasonic oscillator until the solution is white and turbid to obtain a turbid liquid;
dripping the turbid liquid on the surface of the electrode element drop by drop, drying by hot air, and repeating the operation until the thickness of the sensitive layer is about 2 mm;
welding an electrode element on a detection base of the gas-sensitive test system, then placing the electrode element on an aging table, heating the electrode element to 200-300 ℃ at a speed of 2 ℃/min, and preserving heat for 24-36 hours to obtain SnO2H with nano material as sensitive layer2And (S) a gas sensor.
SnO prepared from2H with nano material as sensitive layer2S gas sensor, which is made of SnO2The nano material is a gas-sensitive material, the gas-sensitive material is uniformly coated on the surface of an electrode element, and the electrode element is a planar electrode.
SnO prepared by taking Pt as catalyst2Nanomaterial of said SnO2The nano material is in a comb-shaped structure, and nanowires densely grow around the surface of the trunk; the nano material is SnO with a rutile tetragonal phase crystal structure2Forming; the diameter of the trunk is 100-500 nm, the length of the trunk is 100-500 mu m, the diameter of the nanowire is 80-200 nm, and the length of the nanowire is 400 nm-2 mu m.
The hot air drying of the invention has no specific temperature requirement and can be carried out.
The invention has the beneficial effects that:
1. the method can be carried out under normal pressure, is simple to operate, controls the trace oxygen using amount by utilizing the needle valve, and has high test repeatability.
2. The porous ceramic substrate is placed at an angle of 30-60 degrees with the direction of the air inlet, so that the yield of products is improved.
3. Promoting SnO based on metal Pt catalyst2The formation of nano material structure can raise its specific surface area and nanoThe number of the meter junctions and the co-doping of Pt and Si can lead the material to have H at lower working temperature2The S gas has high sensitivity, quick response and recovery and good selectivity. H of the invention2Excellent low temperature H of S gas sensor2S gas-sensitive characteristic, which makes it hopeful to become high-efficiency H in mining production field2And (S) a gas sensor.
Drawings
Fig. 1(a) and 1(b) are front and back sides of a schematic structural view of a planar electrode in embodiments 1 to 3 of the present invention, in which 1: an alumina substrate; 2: a gold electrode; 3: a platinum guide wire; 4: a ruthenium oxide heating layer; 5: a gas sensitive material layer;
FIG. 2 is a schematic structural view of a thermal evaporation apparatus according to embodiments 1 to 3 of the present invention; a: a porous ceramic substrate; b: high-purity tin particles; c: an alumina porcelain boat; d: a quartz tube; e: sealing the flange; f: an air inlet; g: an air outlet;
FIG. 3 is an X-ray diffraction pattern of the product prepared in example 1 of the present invention;
FIG. 4(4-1) is a low-power SEM photograph of the product prepared in example 1 of the present invention, and (4-2) is a high-power SEM photograph of a side view.
FIG. 5(5-1) is a full X-ray photoelectron spectroscopy scan of the product prepared in example 1 of the present invention; (5-2) is a high-resolution X-ray photoelectron spectrum of Pt element; and (5-3) is a high-resolution X-ray photoelectron spectrum of the Si element.
FIG. 6(6-1) is a graph showing the sensor pair prepared in example 1 of the present invention at 3ppm H2A relation graph between the sensitivity of S and the working temperature; (6-2) sensor Pair 3ppm H2A graph of the response/recovery time of S versus operating temperature; (6-3) the sensor is used for measuring different concentrations H at the working temperature of 85 DEG C2A dynamic response curve of S; (6-4) sensitivity of sensor at 85 ℃ working temperature and H2A graph of the relationship between S concentrations;
FIG. 7 shows the sensitivity of the sensor prepared in example 1 of the present invention to different gases to be detected at an operating temperature of 85 ℃.
Detailed Description
The following non-limiting examples are presented to enable those of ordinary skill in the art to more fully understand the present invention and are not intended to limit the invention in any way.
The test methods described in the following examples are all conventional methods unless otherwise specified; the reagents and materials are commercially available, unless otherwise specified.
Example 1
H based on planar electrode2The S sensor element, whose schematic structural diagram is shown in fig. 1, is composed of an alumina substrate, a gold electrode, a platinum lead wire, a ruthenium oxide heating layer, and a gas-sensitive material layer. Two gold electrodes with the width of 0.3mm are respectively fixed on the front surface and the back surface of the substrate, and the distance between the electrodes is 0.15 mm; the back surface of the substrate is made of RuO2The heating layer is composed of layers, and gold electrodes on the front and back surfaces of the substrate are welded on the base through platinum wire leads. The gas sensitive material is uniformly dripped on the front surface of the substrate and stacked to form a nanowire latticed sensitive layer.
SnO prepared by taking Pt as catalyst2The method of the nano material comprises the following steps:
sputtering a layer of Pt film on the surface of the porous ceramic substrate by a direct current sputtering instrument, wherein the sputtering current is 8mA, and the sputtering time is 60 s;
0.2g of Sn particles with a purity of 99.99% was placed in the middle of an alumina porcelain boat, and the side of the porous ceramic substrate coated with a Pt film was oriented toward the Sn particles and placed at an angle of 45 degrees to the direction of the gas inlet, and the boat was fed into the central heating zone of the quartz tube of the tube furnace and sealed by mounting a flange, as shown schematically in FIG. 2.
Introducing argon with the purity of 99.99% into the tube furnace at the flow rate of 200ml/min for 20min, adjusting the flow rate of the argon to 50ml/min, simultaneously starting a heating device, heating to 900 ℃ at the heating rate of 10 ℃/min, and preserving heat for 60 min; wherein, when the temperature of the tube furnace rises to 200 ℃, oxygen with the purity of 99.99 percent is introduced into the tube furnace; the flow of the oxygen is controlled by a needle valve with scales, and the opening degree of the needle valve is 2 circles.
After the tube furnace is naturally cooled to the room temperature, closing argon and oxygen, and takingTaking out the alumina porcelain boat, lightly scraping the white flocculent product from the surface of the porous ceramic substrate, and then carrying out SnO treatment on the obtained product2Analyzing the structural characteristics of the nano material;
in the above steps, the porous ceramic substrate is made of kaolin, and a pore-forming agent pore-forming method is adopted in the porous treatment method, wherein the pore-forming agent is PMMA microspheres with an average diameter of 30 μm and an addition ratio of 30 wt.%; the forming method adopts a mould pressing sintering method, the sintering temperature is 1200 ℃, and the porous ceramic substrate has the length of 20mm, the width of 10mm and the thickness of 2 mm.
SnO (stannic oxide)2H of nanomaterial2S gas sensor, SnO produced by the method2The nano material is a gas-sensitive material, and the gas-sensitive material is uniformly dripped on the surface of the electrode element.
One kind of SnO2H of nanomaterial2The preparation method of the S gas sensor comprises the following steps:
SnO prepared by the method2Dispersing the nano material in a 2ml conical centrifuge tube filled with 0.5ml absolute ethyl alcohol, and then uniformly dispersing in an ultrasonic oscillator until the solution is white and turbid to obtain a suspension;
and (4) extracting the suspension by using a liquid transfer machine, dripping the suspension on the surface of the electrode element dropwise, drying the electrode element by using hot air, and repeating the operation until the thickness of the sensitive layer is about 2 mm.
Welding an electrode element on a detection base of the gas-sensitive test system, then placing the electrode element on an aging table, heating the electrode element to 300 ℃ at a speed of 2 ℃/min, and preserving heat for 36h to finally obtain SnO2H of nanomaterial2And (S) a gas sensor.
The XRD pattern of the product obtained on the surface of the porous ceramic substrate by thermal evaporation based on the "gas-liquid-solid" growth mechanism is shown in FIG. 3. As can be seen from the figure, all diffraction peaks except for the cristobalite phase and the mullite phase from the porous ceramic substrate can correspond to SnO having a rutile tetragonal crystal structure2(JCPDS number 41-1445). FIG. 4-1 is a low-magnification scanning electron micrograph of the obtained product, which shows that the product exhibits an obvious comb-like structure. FIG. 4-2 shows the high magnification of the productScanning electron micrograph, SnO obtained2The diameter of the trunk of the nano material is 100-500 nm, the length of the trunk is 100-500 mu m, and nanowires with the diameter of 80-200 nm and the length of 400 nm-2 mu m are densely arranged around the surface of the trunk. Fig. 5 is an X-ray photoelectron spectrum of the obtained product, from which it can be seen that there are a small amount of Pt distribution and Si distribution in the product, which are derived from the residue of Pt in the catalyst layer during thermal evaporation and the unintentional doping of Si in the porous ceramic substrate, respectively, in addition to the characteristic peaks of Sn, O, and C. FIG. 6-1 is based on SnO2The gas sensor of the nano material can be used for detecting 3ppm H under different working temperature conditions2The sensitivity of S. It can be seen from the figure that the sensor achieves a maximum sensitivity value of 65 at an operating temperature of 85 ℃. FIG. 6-2 shows the gas sensor at different working temperatures for 3ppm H2S, the response/recovery time is obviously reduced along with the increase of the working temperature, and the response/recovery time at the optimal working temperature of 85 ℃ is respectively 3S and 396S, which shows that the sensor can show excellent gas-sensitive characteristics at low working temperature. FIGS. 6-3 are graphs of gas sensor operating at 85 deg.C for different concentrations H2Dynamic response curve of S, corresponding sensitivity and H2The relationship between the S concentrations is shown in FIGS. 6-4. As can be seen, the sensor is at discharge H2After S, the resistance can be fully restored to its original baseline, indicating that the sensor has good response recovery characteristics. At low temperature, most of H is currently in use2The resistance of an S gas sensor typically does not recover fully to its original baseline, but only by an additional pulse voltage, which significantly increases the cost of manufacturing the sensor. Fig. 7 is a graph of the sensitivity of the gas sensor to different types of gases at an operating temperature of 85 c. From the figure, the sensor pair can be seen to be 3ppm H2The sensitivity of S is maximal and is obviously higher than 30ppm SO2And 1000ppm of other interfering gases, indicating its sensitivity to H2S has excellent selectivity.
Example 2
H based on planar electrode2S sensor element, the structure of which is shown in FIG. 1, is composed of alumina substrate and Au electrodeThe electrode, a platinum lead wire, a ruthenium oxide heating layer and a gas-sensitive material layer. Two gold electrodes with the width of 0.3mm are respectively fixed on the front surface and the back surface of the substrate, and the distance between the electrodes is 0.15 mm; the back surface of the substrate is made of RuO2The heating layer is composed of layers, and gold electrodes on the front and back surfaces of the substrate are welded on the base through platinum wire leads. The gas sensitive material is uniformly dripped on the front surface of the substrate and stacked to form a nanowire latticed sensitive layer.
SnO prepared by taking Pt as catalyst2The method of the nano material comprises the following steps:
sputtering a layer of Pt film on the surface of the porous ceramic substrate by a direct current sputtering instrument, wherein the sputtering current is 8mA, and the sputtering time is 60 s;
0.2g of Sn particles with a purity of 99.99% was placed in the middle of an alumina porcelain boat, and the side of the porous ceramic substrate coated with a Pt film was oriented toward the Sn particles and placed at an angle of 45 degrees to the direction of the gas inlet, and the boat was fed into the central heating zone of the quartz tube of the tube furnace and sealed by mounting a flange, as shown schematically in FIG. 2.
Introducing argon with the purity of 99.99% into the tube furnace at the flow rate of 200ml/min for 20min, adjusting the flow rate of the argon to 50ml/min, simultaneously starting a heating device, heating to 900 ℃ at the heating rate of 10 ℃/min, and preserving heat for 60 min; wherein, when the temperature of the tube furnace rises to 200 ℃, oxygen with the purity of 99.99 percent is introduced into the tube furnace; the flow of the oxygen is controlled by a needle valve with scales, and the opening degree of the needle valve is 2 circles.
After the tube furnace is naturally cooled to room temperature, argon and oxygen are closed, the alumina porcelain boat is taken out, the white flocculent product is gently scraped from the surface of the porous ceramic substrate, and then the obtained SnO is treated2Analyzing the structural characteristics of the nano material;
the porous ceramic substrate in the above steps is made of diatomite, and the porousness treatment method adopts a pore-forming agent pore-forming method, wherein the pore-forming agent is spherical graphite, the average diameter is 24 μm, and the addition ratio is 40 wt.%; the forming method adopts a mould pressing sintering method, the sintering temperature is 1000 ℃, and the porous ceramic substrate has the length of 20mm, the width of 10mm and the thickness of 2 mm.
On the basis of the SnO2H prepared from nano material2S gas sensor, which uses the SnO2The nano material is a gas-sensitive material, and the gas-sensitive material is uniformly dripped on the surface of the electrode element.
On the basis of the SnO2H of nanomaterial2The preparation method of the S gas sensor comprises the following steps:
the above SnO2Dispersing the nano material in a 2ml conical centrifuge tube filled with 0.5ml absolute ethyl alcohol, and then uniformly dispersing in an ultrasonic oscillator until the solution is white and turbid to obtain a suspension;
and (4) extracting the suspension by using a liquid transfer machine, dripping the suspension on the surface of the electrode element dropwise, drying the electrode element by using hot air, and repeating the operation until the thickness of the sensitive layer is about 2 mm.
Welding an electrode element on a detection base of the gas-sensitive test system, then placing the electrode element on an aging table, heating to 300 ℃ at a speed of 2 ℃/min, and preserving heat for 36h to finally obtain SnO2H of nanomaterial2And (S) a gas sensor.
Upon examination, the SnO base prepared in this example2The gas sensor of the nano material is used for detecting 0.5-10 ppm H at the working temperature of 85 DEG C2S has good gas-sensitive characteristics.
Example 3
H based on planar electrode2The S sensor element, whose schematic structural diagram is shown in fig. 1, is composed of an alumina substrate, a gold electrode, a platinum lead wire, a ruthenium oxide heating layer, and a gas-sensitive material layer. Two gold electrodes with the width of 0.3mm are respectively fixed on the front surface and the back surface of the substrate, and the distance between the electrodes is 0.15 mm; the back surface of the substrate is made of RuO2The heating layer is composed of layers, and gold electrodes on the front and back surfaces of the substrate are welded on the base through platinum wire leads. The gas sensitive material is uniformly dripped on the front surface of the substrate and stacked to form a nanowire latticed sensitive layer.
SnO prepared by taking Pt as catalyst2The method of the nano material comprises the following steps:
sputtering a layer of Pt film on the surface of the porous ceramic substrate by a direct current sputtering instrument, wherein the sputtering current is 12mA, and the sputtering time is 60 s;
0.2g of Sn particles with a purity of 99.99% was placed in the middle of an alumina porcelain boat, and the side of the porous ceramic substrate coated with a Pt film was oriented toward the Sn particles and placed at an angle of 45 degrees to the direction of the gas inlet, and the boat was fed into the central heating zone of the quartz tube of the tube furnace and sealed by mounting a flange, as shown schematically in FIG. 2.
Introducing argon with the purity of 99.99% into the tube furnace at the flow rate of 200ml/min for 20min, adjusting the flow rate of the argon to 50ml/min, simultaneously starting a heating device, heating to 900 ℃ at the heating rate of 10 ℃/min, and preserving heat for 60 min; wherein, when the temperature of the tube furnace rises to 200 ℃, oxygen with the purity of 99.99 percent is introduced into the tube furnace; the flow of the oxygen is controlled by a needle valve with scales, and the opening degree of the needle valve is 2 circles.
After the tube furnace is naturally cooled to room temperature, argon and oxygen are closed, the alumina porcelain boat is taken out, the white flocculent product is gently scraped from the surface of the porous ceramic substrate, and then the obtained SnO is treated2Analyzing the structural characteristics of the nano material;
in the above steps, the porous ceramic substrate is made of kaolin, and a pore-forming agent pore-forming method is adopted in the porous treatment method, wherein the pore-forming agent is PMMA microspheres with an average diameter of 30 μm and an addition ratio of 30 wt.%; the forming method adopts a mould pressing sintering method, the sintering temperature is 1200 ℃, and the porous ceramic substrate has the length of 20mm, the width of 10mm and the thickness of 2 mm.
One is based on the SnO2H prepared from nano material2S gas sensor, which uses the SnO2The nano material is a gas-sensitive material, and the gas-sensitive material is uniformly dripped on the surface of the electrode element.
On the basis of the SnO2H of nanomaterial2The preparation method of the S gas sensor comprises the following steps:
SnO prepared by the above method2Dispersing the nano material in a 2ml conical centrifuge tube filled with 0.5ml absolute ethyl alcohol, and then uniformly dispersing in an ultrasonic oscillator until the solution is white and turbid to obtain a suspension;
and (4) extracting the suspension by using a liquid transfer machine, dripping the suspension on the surface of the electrode element dropwise, drying the electrode element by using hot air, and repeating the operation until the thickness of the sensitive layer is about 2 mm.
Welding an electrode element on a detection base of the gas-sensitive test system, then placing the electrode element on an aging table, heating to 300 ℃ at a speed of 2 ℃/min, and preserving heat for 36h to finally obtain SnO2H of nanomaterial2And (S) a gas sensor.
Upon examination, the SnO base prepared in this example2The gas sensor of the nano material is used for detecting 0.5-10 ppm H at the working temperature of 85 DEG C2S has good gas-sensitive characteristics.
Claims (5)
1. SnO prepared by taking Pt as catalyst2Nanomaterial characterized in that said SnO2The nano material is in a comb-shaped structure, and nanowires densely grow around the surface of the trunk; the nano material is SnO with a rutile tetragonal phase crystal structure2Forming; the diameter of the trunk is 100-500 nm, the length of the trunk is 100-500 mu m, the diameter of the nanowire is 80-200 nm, and the length of the nanowire is 400 nm-2 mu m;
the SnO2The nano material is prepared according to the following method:
sputtering a layer of Pt film on the surface of a porous ceramic substrate by a direct current sputtering instrument, wherein the sputtering current is 4-12 mA, and the sputtering time is 45-60 s;
placing 0.2-0.5 g of Sn particles with the purity of 99.99% in the middle of an alumina ceramic boat, placing the side of the porous ceramic substrate plated with the Pt film facing the Sn particles at an angle of 30-60 degrees with the direction of an air inlet, sending the ceramic boat into a central heating area of a quartz tube of a tube furnace, and installing a flange for sealing;
thirdly, argon with the purity of 99.99 percent is introduced into the tube furnace at the flow rate of 200-300 ml/min for 20min, then the flow rate of the argon is adjusted to 50-100 ml/min, meanwhile, a heating device is started, the temperature is increased to 900-1000 ℃ at the temperature increase rate of 5-10 ℃/min, and the temperature is kept for 60-90 min; when the temperature of the tube furnace rises to 200-300 ℃, introducing oxygen with the purity of 99.99% into the tube furnace; the flow of the oxygen is controlled by a needle valve with scales, and the opening degree of the needle valve is 2-5 circles;
fourthly, after the tube furnace is naturally cooled to the room temperature, argon and oxygen are closed, the alumina porcelain boat is taken out, the white flocculent product is scraped from the surface of the porous ceramic substrate, and the white flocculent product is SnO prepared by taking Pt as a catalyst2And (3) nano materials.
2. A SnO according to claim 12The nano material is characterized in that the porous ceramic substrate is made of diatomite or kaolin containing aluminosilicate components, porous treatment is carried out by adopting a pore-forming agent pore-forming method, the pore-forming agent is spherical graphite or PMMA microspheres, the average diameter of the pore-forming agent is 10-70 mu m, the adding proportion is 20-50 wt.%, molding and sintering are carried out by adopting a mold pressing sintering method, and the sintering temperature is 1000-1200 ℃.
3. A SnO according to claim 12The nano material is characterized in that the length of the porous ceramic substrate is 15-20 mm, the width of the porous ceramic substrate is 5-10 mm, and the thickness of the porous ceramic substrate is 1-2 mm.
4. The SnO compound of claim 12H with nano material as sensitive layer2S gas sensor, characterized in that it is made of SnO according to claim 12The nano material is a gas-sensitive material, the gas-sensitive material is uniformly coated on the surface of an electrode element, and the electrode element is a planar electrode.
5. H according to claim 42The preparation method of the S gas sensor is characterized by comprising the following steps:
the SnO of claim 12Pouring the nano material into a 2ml conical centrifuge tube filled with 0.5ml absolute ethyl alcohol, and uniformly dispersing in an ultrasonic oscillator until the solution is white and turbid to obtain a turbid liquid;
dripping the turbid liquid on the surface of the electrode element drop by drop, drying by hot air, and repeating the operation until the thickness of the sensitive layer is about 2 mm;
welding the electrode element on the detection base of the gas-sensitive test system,then placing the mixture on an aging table, heating the mixture to 200-300 ℃ at the speed of 2 ℃/min, and preserving heat for 24-36 hours to obtain SnO2H with nano material as sensitive layer2And (S) a gas sensor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910253135.1A CN109911929B (en) | 2019-03-29 | 2019-03-29 | SnO prepared by taking Pt as catalyst2Method and application of nano material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910253135.1A CN109911929B (en) | 2019-03-29 | 2019-03-29 | SnO prepared by taking Pt as catalyst2Method and application of nano material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109911929A CN109911929A (en) | 2019-06-21 |
| CN109911929B true CN109911929B (en) | 2021-09-28 |
Family
ID=66967868
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910253135.1A Active CN109911929B (en) | 2019-03-29 | 2019-03-29 | SnO prepared by taking Pt as catalyst2Method and application of nano material |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109911929B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112225245B (en) * | 2019-06-28 | 2022-08-16 | 东北大学 | Rare earth element doped SnO 2 Basic high response SO 2 Method for preparing sensitive material |
| CN110261445B (en) * | 2019-07-12 | 2020-05-29 | 东北大学 | In-situ growth nanometer In based on non-metallic mineral electrode substrate surface2O3Room temperature NO of2Sensor and preparation method |
| CN111116232A (en) * | 2019-12-13 | 2020-05-08 | 苏州麦茂思传感技术有限公司 | Synthesis method of formaldehyde gas sensor sensitive material |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102623635A (en) * | 2012-03-29 | 2012-08-01 | 杭州电子科技大学 | Tin dioxide based resistance type random read memorizer and preparation method thereof |
-
2019
- 2019-03-29 CN CN201910253135.1A patent/CN109911929B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN109911929A (en) | 2019-06-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109911929B (en) | SnO prepared by taking Pt as catalyst2Method and application of nano material | |
| Chen et al. | Effects of morphologies on acetone-sensing properties of tungsten trioxide nanocrystals | |
| Williams et al. | Gas sensing properties of nanocrystalline metal oxide powders produced by a laser evaporation technique | |
| Song et al. | Characterization of electrospun ZnO–SnO2 nanofibers for ethanol sensor | |
| Zhong et al. | SO2 sensing properties of SnO2 nanowires grown on a novel diatomite-based porous substrate | |
| Bai et al. | Microstructure and gas sensing properties of the ZnO thick film treated by hydrothermal method | |
| Sheng et al. | Humidity sensing properties of bismuth phosphates | |
| CN110261445B (en) | In-situ growth nanometer In based on non-metallic mineral electrode substrate surface2O3Room temperature NO of2Sensor and preparation method | |
| Pilliadugula et al. | Effect of pH dependent morphology on room temperature NH3 sensing performances of β-Ga2O3 | |
| Ryzhikov et al. | Organometallic synthesis of ZnO nanoparticles for gas sensing: Towards selectivity through nanoparticles morphology | |
| Xie et al. | Facile synthesis and superior ethyl acetate sensing performance of Au decorated ZnO flower-like architectures | |
| CN103217460A (en) | Cobaltosic oxide nanowire array based alcohol gas sensor and preparation method thereof | |
| CN108535334B (en) | Preparation method of methanol gas sensor with tin oxide nano-particles and zinc oxide nano-wire agglomeration structure | |
| Shen et al. | Preparation of one-dimensional SnO 2–In 2 O 3 nano-heterostructures and their gas-sensing property | |
| CN107164839A (en) | Formaldehyde sensitive material CdGa2O4 with hypersensitivity and selectivity and preparation method thereof | |
| Zhong et al. | Effect of pore structure of the metakaolin-based porous substrate on the growth of SnO2 nanowires and their H2S sensing properties | |
| Zhan et al. | Flame aerosol reactor synthesis of nanostructured SnO2 thin films: High gas-sensing properties by control of morphology | |
| CN109916965A (en) | It is a kind of using FTO electro-conductive glass as the ZnO nano cluster gas sensor of electrode member | |
| Yoo et al. | Nanocarving of titania (TiO2): a novel approach for fabricating chemical sensing platform | |
| 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 | |
| Yao et al. | A high sensitivity and selectivity n-butanol sensor based on monodispersed Pd-doped SnO2 nanoparticles mediated by glucose carbonization | |
| CN107024513B (en) | Gas sensor, gas sensing device and system | |
| Xu et al. | Synthesis and NO 2 sensing properties of indium oxide nanorod clusters via a simple solvothermal route | |
| CN110615693A (en) | Hydrogen sulfide gas sensing material, sensor, preparation method and use method | |
| Muthuvinayagam et al. | Enhanced LPG sensing property of sol–gel synthesized ZnO nanoparticles-based gas sensors |
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 |