Construction method and application of hydrogen sulfide gas sensor driven by metal single atoms

Abstract

The invention relates to the technical field of hydrogen sulfide gas sensors, in particular to a construction method and application of a metal monatomic driven hydrogen sulfide gas sensor, and the construction method comprises the following steps: dissolving indium trichloride tetrahydrate and thiourea in isopropanol and deionized water, and uniformly stirring to obtain a precursor transparent solution; carrying out hydrothermal reaction on the precursor solution; obtaining a first dried sample; calcining the first dried sample to obtain an indium oxide nanosphere precursor; uniformly mixing the indium oxide nanosphere precursor with deionized water to obtain a first mixed solution, mixing the first mixed solution with an ammonium carbonate solution, adding a ruthenium acetylacetonate solution, mixing to obtain a second mixed solution, centrifuging, and drying to obtain a second dried sample; calcining the second dried sample to obtain the indium oxide nanosphere gas-sensitive material; the method comprises the following steps: dispersing an indium oxide nanosphere gas-sensitive material in absolute ethyl alcohol, and dispensing onto the surface of a planar electrode to construct a hydrogen sulfide gas sensor; according to the invention, high-efficiency detection of hydrogen sulfide gas is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen sulfide gas sensors, and in particular to a construction method and application of a metal single atom driven hydrogen sulfide gas sensor. Background Art

[0002] Hydrogen sulfide, an acidic and hazardous air pollutant, not only has a strong rotten egg odor but is also a colorless, flammable, and corrosive gas. Due to the lack of oxygen in sewers, sulfur-containing organic matter in sewage is directly decomposed by anaerobic microorganisms, producing hydrogen sulfide gas, which is widely emitted in cities. Second only to hydrocyanic acid in toxicity among all toxic gases, hydrogen sulfide has become a focus of environmental safety research due to its high toxicity. Studies have shown that exposure to hydrogen sulfide gas can cause a range of health effects in the human body, including respiratory, nervous, metabolic, reproductive, and even death. Long-term exposure to low concentrations of H2S can cause discomfort to the central nervous system, while short-term exposure to high concentrations can cause loss of smell and even death. Therefore, a highly efficient, miniaturized, highly sensitive, fast-response, and low-power H2S gas sensor is needed.

[0003] Indium oxide is a wide-bandgap n-type metal oxide semiconductor (Eg = 3.55–3.75 eV) with abundant oxygen vacancies, excellent conductivity, and superior electrochemical stability. As a highly sensitive gas-sensing material, it is widely used in gas sensors. However, most metal oxide semiconductors suffer from shortcomings such as slow response recovery, poor selectivity, and poor stability. A deeper understanding of the application areas of single-atom catalysts reveals that metal oxide semiconductors modified with noble metal single atoms exhibit higher selectivity and sensitivity than metal oxide semiconductors alone. However, there are few reports on resistive metal oxide gas sensors using single-atom catalysis to detect hydrogen sulfide gas with high sensitivity and selectivity.

[0004] Therefore, the hydrogen sulfide gas sensor based on ruthenium single atom catalyzed indium oxide nanosphere composite gas-sensitive material we proposed has a wide range of application scenarios. It can not only protect human health, but also monitor the environment and contribute to environmental protection. Summary of the Invention

[0005] The object of the present invention is to provide a method for constructing a semiconductor gas sensor for hydrogen sulfide gas detection and its application, so as to solve the above-mentioned problems.

[0006] The technical problems solved by the present invention are: The purpose of the present invention can be achieved through the following technical solutions: A method for constructing a metal single atom-driven hydrogen sulfide gas sensor comprises the following steps: Indium trichloride tetrahydrate and thiourea were dissolved in isopropyl alcohol and deionized water, and stirred uniformly to obtain a transparent precursor solution; the precursor solution was subjected to a hydrothermal reaction for 16 hours; After the hydrothermal reaction is completed, the sample is naturally cooled to room temperature, washed, centrifuged, and dried to obtain a first dried sample; The first dried sample was calcined at 500°C in air atmosphere for 2 h to obtain an indium oxide nanosphere precursor; The indium oxide nanosphere precursor is evenly mixed with deionized water to obtain a first mixed solution. The first mixed solution is mixed with an ammonium carbonate solution, and then an acetylacetonate ruthenium solution is added to mix to obtain a second mixed solution. Finally, the second mixed solution is centrifuged and dried to obtain a second dried sample.

[0007] The second dried sample was calcined at 500°C for 2 h in an argon atmosphere to obtain a ruthenium single atom-catalyzed indium oxide nanosphere gas sensing material; The ruthenium single atom-catalyzed indium oxide nanosphere gas-sensitive material was dispersed in anhydrous ethanol and further drop-coated onto the surface of a planar electrode to construct a hydrogen sulfide gas sensor.

[0008] As a further embodiment of the present invention, the usage ratio of indium trichloride tetrahydrate, thiourea, isopropyl alcohol and deionized water is 586.4 mg:456.8 mg:22 mL:4 mL.

[0009] As a further solution of the present invention: the washing, centrifugation and drying process of the first dried sample includes: centrifugal washing 4 times, the centrifugal speed is 8000 rpm, and the centrifugal time is 5 minutes.

[0010] As a further solution of the present invention: the drying temperature of the first dried sample and the second dried sample is 60-80° C., and the drying time is 6-48 hours.

[0011] As a further solution of the present invention: the heating rate during the calcination of the first dried sample and the second dried sample is 2°C·min -1 .

[0012] As a further solution of the present invention: the parameters for centrifugation of the second mixed solution are centrifugal washing once, a centrifugal speed of 8000 rpm, and a centrifugal time of 5 minutes.

[0013] As a further solution of the present invention: the morphology of the indium oxide nanosphere composite gas-sensitive material catalyzed by ruthenium single atom is spherical.

[0014] As a further solution of the present invention: the particle size of the indium oxide nanosphere composite gas-sensitive material catalyzed by ruthenium single atom is 7 μm.

[0015] An application of a metal single-atom driven hydrogen sulfide gas sensor, such as the ruthenium single-atom catalyzed indium oxide nanosphere composite gas-sensitive material prepared by the above method, is dispersed in anhydrous ethanol and then drop-coated on a planar electrode surface using a pipette. After it is completely dried, a gas sensor is constructed and further used for hydrogen sulfide gas sensing testing.

[0016] Beneficial effects of the present invention: The preparation method of the entire ruthenium single-atom-catalyzed indium oxide nanosphere composite gas-sensitive material of the present invention is simple and easy to operate, and the sensor constructed based on the obtained ruthenium single-atom-catalyzed indium oxide nanosphere composite gas-sensitive material exhibits excellent sensing characteristics such as high sensitivity, high stability, and high selectivity to hydrogen sulfide gas; In the present invention, when the ruthenium single atom-catalyzed indium oxide nanosphere composite gas-sensitive material is used in the construction process of a hydrogen sulfide gas sensor, the prepared ruthenium single atom-catalyzed indium oxide nanosphere composite gas-sensitive material is subjected to a sensor sensitive thin film process to construct a hydrogen sulfide gas sensor, which can achieve a rapid sensing response to hydrogen sulfide gas and exhibit excellent gas-sensitive properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 This is a SEM image of a sample of an indium oxide nanosphere composite gas-sensitive material catalyzed by a single ruthenium atom prepared in the present invention; Figure 2 This is an XRD picture of the indium oxide nanosphere composite gas-sensitive material catalyzed by ruthenium single atom provided by the present invention; Figure 3 The gas-sensing performance test of the indium oxide nanosphere composite gas-sensitive material catalyzed by ruthenium single atom prepared by the present invention to hydrogen sulfide gas at a working temperature of 175°C is Response (R air / R gas )-Time(s) curve; Figure 4 A bar chart of the gas-sensitive test response values of the ruthenium single-atom-catalyzed indium oxide nanosphere composite gas-sensitive material prepared by the present invention to seven gases, namely hydrogen, methane, ammonia, sulfur dioxide, nitrogen dioxide, trimethylamine, and hydrogen sulfide, at a working temperature of 175°C. DETAILED DESCRIPTION

[0019] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0020] Example 1 The present invention provides a method for constructing a metal single atom-driven hydrogen sulfide gas sensor, which specifically includes the following steps: Step 1: Weigh 586.4 mg of indium trichloride tetrahydrate and 456.8 mg of thiourea, dissolve them in 22 ml of isopropanol and 4 ml of deionized water, and stir evenly for 30 minutes to obtain a transparent precursor solution; transfer the transparent precursor solution to a 50 ml polytetrafluoroethylene liner, seal the liner and place it in a reactor, and place the reactor in an oven for hydrothermal reaction for 16 hours; Step 2: After the hydrothermal reaction is completed, the reactor is cooled naturally to room temperature, the reactor is opened and the liner is removed, the suspension in the liner is transferred to a 50 mL centrifuge tube, and the brick-red precipitate in the liner is washed and centrifuged with deionized water and anhydrous ethanol, and the collected brick-red precipitate is dried; The brick-red precipitate in the lining was centrifuged and washed 4 times at a centrifugal speed of 8000 rpm and a centrifugal time of 5 minutes; the drying temperature was 60-80°C and the drying time was 6-48 hours; Step 3: calcining the obtained dried sample at 500° C. in air atmosphere for 2 h to obtain an indium oxide gas-sensitive material; The heating rate during the calcination process was 2°C·min -1 ; Step 4: Weigh 0.100 g of the prepared indium oxide nanosphere precursor, mix it evenly with 5 mL of deionized water, and stir it with a magnetic stirrer for 5 minutes to obtain a first mixed solution. The first mixed solution was mixed with 2.5 mL of 1 mol / L ammonium carbonate solution, and 50 μL of ruthenium acetylacetonate solution was added. The mixed solution was magnetically stirred for 2 hours to obtain a second mixed solution. Finally, the second mixed solution was centrifuged in a centrifuge for 5 minutes, and the precipitate after removing the supernatant was dried; The drying temperature is 60-80°C and the drying time is 6-48h; Step 5: calcining the dried sample obtained in step 4 at 500° C. for 2 h in an argon atmosphere to obtain a ruthenium single atom-catalyzed indium oxide nanosphere gas-sensitive material; The heating rate during the calcination process was 2°C·min -1The morphology of the indium oxide nanosphere composite gas-sensing material catalyzed by ruthenium single atoms is spherical, with a particle size of about 7 μm. Step 6: Disperse 2 mg of ruthenium single-atom-catalyzed indium oxide nanospheres in 30 μL of anhydrous ethanol and further drop-coat them onto the surface of a planar electrode to construct a semiconductor sensor that can be used to detect hydrogen sulfide gas.

[0021] The preparation process of the ruthenium single atom-catalyzed indium oxide nanosphere composite gas-sensitive material is simple and easy, and the sensor constructed based on the obtained ruthenium single atom-catalyzed indium oxide nanosphere composite gas-sensitive material exhibits high sensitivity, high stability, high selectivity and other sensing properties for the detection of hydrogen sulfide gas.

[0022] Example 2 The present invention provides an application of a metal single-atom driven hydrogen sulfide gas sensor. The ruthenium single-atom catalyzed indium oxide nanosphere composite gas-sensitive material prepared in the above embodiment can be used for the rapid detection of hydrogen sulfide gas substances. Specifically: 2 mg of ruthenium single-atom-catalyzed indium oxide nanospheres were dispersed in 30 μL of anhydrous ethanol and further drop-coated onto a planar electrode surface to construct a semiconductor sensor for detecting hydrogen sulfide gas. When the ruthenium single atom-catalyzed indium oxide nanosphere composite gas-sensitive material is used in the production process of the hydrogen sulfide gas sensor, the ruthenium single atom-catalyzed indium oxide nanosphere composite gas-sensitive material prepared in the above embodiment is subjected to a sensor sensitive thin film process to construct a hydrogen sulfide gas sensor, which can achieve a rapid sensing response to hydrogen sulfide gas and quickly exhibit excellent gas-sensitive properties.

[0023] Performance Testing During the morphology observation and performance testing of the ruthenium single atom-catalyzed indium oxide nanosphere composite gas-sensing material sample prepared in the above embodiment, the following results were obtained: (1) If Figure 1 As shown, from Figure 1 The synthesized ruthenium single-atom-catalyzed indium oxide nanospheres, approximately 7μm in diameter, can be seen in the figure. SEM characterization results reveal that the indium oxide nanospheres are composed of single atoms and have an uneven surface. This structure gives the ruthenium single-atom-catalyzed indium oxide nanospheres a large specific surface area, increasing the contact area between gas molecules and the material and promoting adsorption and diffusion. The introduction of ruthenium single atoms creates a large number of adsorption sites on the indium oxide surface, thereby improving sensitivity and selectivity for hydrogen sulfide gas and ensuring stability in practical applications.

[0024] (2) If Figure 2As shown, it can be clearly seen that there are obvious diffraction peaks at 21.50°, 30.58°, 35.47°, 45.69°, 51.04°, 55.99°, and 60.68°, which correspond to the (211), (222), (400), (431), (440), (611), and (622) crystal planes of indium oxide, respectively. The XRD diffraction pattern is in good agreement with the standard card (JCPDS No. 06–0416), confirming the presence of indium oxide in the composite sample. No additional diffraction peaks were observed in the sample, indicating the high crystallinity of the sample and the absence of impurity peaks. The gas sensing application of the above-mentioned indium oxide nanomaterial of the present invention is that the indium oxide nanomaterial is dispersed in a small amount of ethanol, and then dripped onto the surface of a planar electrode by a pipette gun. After natural drying, it is further constructed into a gas sensor, and then gas sensing detection is performed; the sensor is gas-sensitive tested for hydrogen sulfide gas at an operating temperature of 175°C; (3) If Figure 3 As shown, the dynamic response curve of the sensor prepared based on the composite gas-sensitive material of indium oxide nanospheres catalyzed by ruthenium single atoms to different concentrations (1 to 10 ppm) of hydrogen sulfide gas at a humidity of 40% and an operating temperature of 175°C is shown. It can be seen from the figure that the response value of the sensor based on the composite gas-sensitive material of indium oxide nanospheres catalyzed by ruthenium single atoms is 3.5 at a concentration of 1 ppm, and the response value reaches 70.43 when the concentration is 10 ppm, highlighting the excellent sensing performance. In addition, the sensitivity of the gas sensor increases with the increase of the concentration of hydrogen sulfide gas, indicating that the prepared sensor has good reversibility; (4) If Figure 4 The bar graph shows the response values of a sensor fabricated using a ruthenium single-atom-catalyzed indium oxide nanosphere composite gas-sensing material to seven gases (hydrogen, methane, ammonia, sulfur dioxide, nitrogen dioxide, trimethylamine, and hydrogen sulfide) at a concentration of 10 ppm at 40% humidity and 175°C. The graph demonstrates that the sensor, based on the ruthenium single-atom-catalyzed indium oxide nanosphere composite gas-sensing material, exhibits a good response to hydrogen sulfide.

[0025] In summary, it can be seen that the ruthenium single atom-catalyzed indium oxide nanosphere composite gas-sensing material of the embodiment of the present invention has excellent gas-sensing performance at 175°C.

[0026] The above is a detailed description of an embodiment of the present invention. However, the content described is only a preferred embodiment of the present invention and should not be considered to limit the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A method for constructing a metal single atom driven hydrogen sulfide gas sensor, characterized in that: The following steps are involved: Indium trichloride tetrahydrate and thiourea were dissolved in isopropyl alcohol and deionized water, and stirred uniformly to obtain a transparent precursor solution; the precursor solution was subjected to a hydrothermal reaction for 16 hours; After the hydrothermal reaction is completed, the sample is naturally cooled to room temperature, washed, centrifuged, and dried to obtain a first dried sample; The first dried sample was calcined at 500°C in air atmosphere for 2 h to obtain an indium oxide nanosphere precursor; The indium oxide nanosphere precursor is uniformly mixed with deionized water to obtain a first mixed solution, the first mixed solution is mixed with an ammonium carbonate solution, and then a ruthenium acetylacetonate solution is added to obtain a second mixed solution, and the second mixed solution is centrifuged and dried to obtain a second dried sample; The second dried sample was calcined at 500°C for 2 h in an argon atmosphere to obtain a ruthenium single atom-catalyzed indium oxide nanosphere gas sensing material; The ruthenium single atom-catalyzed indium oxide nanosphere gas-sensitive material was dispersed in anhydrous ethanol and further drop-coated onto the surface of a planar electrode to construct a hydrogen sulfide gas sensor.

2. The method for constructing a metal single atom driven hydrogen sulfide gas sensor according to claim 1, characterized in that: The usage ratio of indium trichloride tetrahydrate, thiourea, isopropyl alcohol and deionized water is 586.4 mg:456.8 mg:22 mL:4 mL.

3. The method for constructing a metal single atom driven hydrogen sulfide gas sensor according to claim 1, characterized in that: The washing, centrifugation and drying process of the first dried sample includes: centrifugal washing 4 times, a centrifugal speed of 8000 rpm, and a centrifugal time of 5 minutes.

4. The method for constructing a metal single atom driven hydrogen sulfide gas sensor according to claim 1, characterized in that: The drying temperature of the first drying sample and the second drying sample is 60-80° C., and the drying time is 6-48 h.

5. The method for constructing a metal single atom driven hydrogen sulfide gas sensor according to claim 1, characterized in that: The heating rate during the calcination of the first dried sample and the second dried sample was 2 °C·min -1 .

6. The method for constructing a metal single atom driven hydrogen sulfide gas sensor according to claim 1, characterized in that: The parameters for the centrifugation of the second mixed solution are: centrifugal washing once, a centrifugal speed of 8000 rpm, and a centrifugal time of 5 minutes.

7. The method for constructing a metal single atom driven hydrogen sulfide gas sensor according to claim 1, characterized in that: The morphology of the indium oxide nanosphere composite gas-sensing material catalyzed by ruthenium single atom is spherical.

8. The method for constructing a metal single atom driven hydrogen sulfide gas sensor according to claim 1, characterized in that: The particle size of the indium oxide nanosphere composite gas-sensing material catalyzed by ruthenium single atom is 7μm.

9. Application of a metal single atom driven hydrogen sulfide gas sensor, characterized in that: The ruthenium single-atom catalyzed indium oxide nanosphere composite gas-sensitive material prepared by the method described in any one of claims 1 to 8 above is dispersed in anhydrous ethanol, and then drop-coated on the surface of a planar electrode through a pipette, and after it is completely dried, a gas sensor is built, and further used for hydrogen sulfide gas sensing testing.

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