Method for constructing semiconductor gas sensor for detecting phosphine gas and application

Abstract

The application belongs to the technical field of sensors, and particularly relates to a semiconductor gas sensor construction method and application for detecting phosphine gas, which comprises the following steps: dissolving zinc nitrate hexahydrate and sodium citrate dihydrate in deionized water, adding sodium hydroxide into the mixed transparent solution to generate a precursor suspension; standing, centrifuging and drying to obtain a first sample; calcining the first sample to obtain a zinc oxide precursor; dissolving the zinc oxide precursor in deionized water, adding a tetrachloroauric acid solution to stir to obtain a second sample; calcining the second sample to obtain a gold single atom modified zinc oxide nanoflower gas sensitive material; and coating the gold single atom modified zinc oxide nanoflower composite gas sensitive material through a sensor sensitive film coating process to construct a phosphine gas sensor. The sensor constructed by the gold single atom modified zinc oxide nanoflower composite gas sensitive material obtained by the application exhibits excellent sensing characteristics such as high sensitivity, high stability and high selectivity for phosphine gas.

Description

Technical Field

[0001] This invention belongs to the field of sensor technology, specifically a method for constructing and applying a semiconductor gas sensor for detecting phosphine gas. Background Technology

[0002] Phosphine (PH3), a highly toxic, colorless, acidic air pollutant, not only has an unpleasant, rotten fish-like odor but is also a flammable, strongly reducing, and highly toxic gas. It is widely released during industrial production (such as aluminum phosphide fumigation, yellow phosphorus smelting, and semiconductor manufacturing), agricultural storage fumigation, and the anaerobic decomposition of organic waste, making it a typical industrial and environmentally hazardous gas. Among common toxic gases, its toxicity is far higher than most volatile organic pollutants, and its acute toxicity is even comparable to cyanide. Therefore, the accurate detection of phosphine gas remains a research focus in the fields of environmental safety and occupational health.

[0003] Studies have shown that exposure to phosphine gas can cause irreversible damage to multiple systems in the human body: long-term exposure to low concentrations of phosphine can lead to chronic health problems such as nervous system damage, respiratory inflammation, and abnormal liver function; short-term inhalation of high concentrations of phosphine can rapidly cause pulmonary edema, central nervous system paralysis, and even death within hours. The International Labour Organization (ILO) and the National Institute for Occupational Safety and Health (NIOSH) have set occupational exposure limits for phosphine at an 8-hour weighted average of 0.3 ppm and a short-term exposure limit of no more than 1 ppm for 10 minutes, which places extremely high demands on the sensitivity of detection devices. Therefore, developing a highly efficient, miniaturized, highly sensitive, fast-response, low-power, and highly selective phosphine gas sensor is an urgent need to ensure occupational safety, environmental monitoring, and public health.

[0004] Zinc oxide possesses abundant oxygen vacancies, excellent electrical conductivity, and electrochemical stability. It also boasts advantages such as readily available raw materials, good biocompatibility, and controllable morphology, making it a high-performance gas-sensitive material widely used in the development of various gas sensors. However, traditional pure-phase metal oxide semiconductor gas-sensitive materials generally suffer from slow response recovery, poor target gas selectivity, and insufficient long-term stability. With the rapid development of single-atom catalysis technology, modifying metal oxide semiconductors with noble metal single atoms can exhibit higher selectivity, sensitivity, and anti-poisoning stability compared to metal oxide semiconductors alone. However, research reports on using single-atom catalysis technology to detect phosphine gas in resistive ZnO-based gas sensors while simultaneously achieving high sensitivity, high selectivity, and strong anti-poisoning capabilities are limited.

[0005] Therefore, we propose a phosphine semiconductor gas sensor based on gold single-atom modified zinc oxide, which has a wide range of applications. It can not only provide real-time and accurate gas monitoring for scenarios such as grain storage, but also be applied to industrial waste gas emission monitoring and environmental quality assessment, thus contributing to environmental protection. Summary of the Invention

[0006] In order to overcome the shortcomings of the prior art, at least one technical problem raised in the background art is solved.

[0007] The technical solution adopted by this invention to solve its technical problem is: a method for constructing a semiconductor gas sensor for detecting phosphine gas, comprising the following steps: Step A: Dissolve zinc nitrate hexahydrate and sodium citrate dihydrate in deionized water, then add sodium hydroxide to the mixed transparent solution to generate a precursor suspension; Step B: Let the precursor suspension stand, remove the supernatant after the precipitate is obtained, wash, centrifuge and dry the obtained product to obtain the first sample; Step C: Calcine the first sample in air at 500°C for 2 hours to obtain zinc oxide nanoflower-like precursor; Step D: Dissolve the zinc oxide nanoflower precursor in deionized water, then add 25 μL of 20 mg / mL tetrachloroauric acid solution, stir, centrifuge, and dry the precipitate to obtain the second sample; Step E: Calcine the second sample at 500°C for 2 hours in an argon atmosphere to obtain zinc oxide nanoflower gas-sensitive material modified with gold single atoms; Step F: Add naphthol and terpineol to the zinc oxide nanoflower gas-sensitive material modified with gold single atoms and grind it to obtain a viscous slurry. Then, coat it onto the surface of the planar electrode and screen print it onto the electrode surface through the planar electrode printing screen. Excess slurry seeps out through the screen and is completely dried to form a semiconductor sensor.

[0008] Preferably, in step A, the ratio of zinc nitrate hexahydrate, sodium citrate dihydrate, deionized water, and sodium hydroxide is 0.68g:1.58g:45mL:0.45g.

[0009] Preferably, in step D, the ratio of zinc oxide nanoflower precursor to deionized water is 50 mg: 25 mL.

[0010] Preferably, in step F, the ratio of the zinc oxide nanoflower gas-sensitive material modified with gold single atoms, naphthol, and terpineol is 25 mg: 2 uL: 16 uL.

[0011] Preferably, in steps B and D, the temperature for drying the precipitate is 60 °C and the drying time is 12-24 h, in order to remove moisture from the precipitate.

[0012] Preferably, in steps C and E, the heating rate of the dried sample during calcination is 2 °C·min. -1 .

[0013] Preferably, in step B, the obtained milky white precipitate is centrifuged and washed three times at a speed of 8000 rpm for 5 min. In step D, the modified gold single-atom zinc oxide gas-sensitive precursor material is centrifuged and cleaned once at a speed of 8000 rpm for 5 min.

[0014] Preferably, the modified gold single-atom zinc oxide nanoflower-like composite gas-sensitive material of the phosphine gas sensor is mainly composed of zinc nitrate hexahydrate.

[0015] Preferably, the zinc oxide nanoflower-like composite gas-sensitive material modified with gold single atoms has a spherical morphology with a diameter of 3 μm.

[0016] An application of a zinc oxide nanoflower-like composite gas-sensitive material modified with gold single atoms: The zinc oxide nanoflower-like composite gas-sensitive material modified with gold single atoms is prepared by the above method. The modified zinc oxide nanoflower-like composite gas-sensitive material is dispersed in a mortar, then naphthol and terpineol are added and ground until the mixture is in the form of a slurry. Then, it is coated onto the surface of a planar electrode by brushing, and then screen-printed on the electrode surface by a planar electrode printing screen. After it is completely dried, a gas sensor is formed and further used for phosphine gas sensing detection.

[0017] The beneficial effects of this invention are as follows: In this invention, the preparation method of the zinc oxide nanoflower-like gas-sensitive material modified with gold single atoms is simple and easy to operate, and the sensor constructed based on the obtained zinc oxide nanoflower-like composite gas-sensitive material modified with gold single atoms exhibits excellent sensing characteristics such as high sensitivity, high stability, and high selectivity for phosphine gas. In the process of constructing a hydrogen sulfide gas sensor using zinc oxide nanoflower-like composite gas-sensitive material modified with gold single atoms, the prepared zinc oxide nanoflower-like composite gas-sensitive material modified with gold single atoms is coated with a sensor sensitive film to construct a phosphine gas sensor, which can realize a rapid sensing response to phosphine gas and exhibit excellent gas-sensitive characteristics. Attached Figure Description

[0018] The invention will now be further described with reference to the accompanying drawings.

[0019] Figure 1 These are SEM images of the zinc oxide nanoflower-like composite gas-sensitive material modified with gold single atoms obtained in this invention. Figure 2 These are XRD images of the zinc oxide nanoflower-like composite gas-sensitive material modified with gold single atoms provided by this invention. Figure 3 The gas-sensing performance (Response(R)) of the modified gold single-atom zinc oxide nanoflower-like composite gas-sensitive material prepared in this invention to phosphine gas at an operating temperature of 275 °C was tested. gas / R air )-Time(s) curve; Figure 4 The zinc oxide nanoflower-like composite gas-sensitive material modified with gold single atoms prepared in this invention exhibits gas-sensing properties against dimethyl sulfide (C2H6S), carbon disulfide (CS2), and n-valeric acid (C5H) at an operating temperature of 275 °C. 10 Bar graph showing the gas-sensitive test response values ​​of nine gases, including O2, propionic acid (C3H6O2), acetic acid (C2H4O2), butyric acid (C4H8O2), acetone (C3H6O), trimethylamine (TMA), and phosphine (PH3). Detailed Implementation

[0020] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0021] Example 1 This invention relates to a method for preparing a modified gold single-atom zinc oxide nanoflower-like composite gas-sensitive material for constructing a phosphine gas sensor, comprising: Step A: Weigh 0.68 g of zinc nitrate hexahydrate and 1.58 g of sodium citrate dihydrate, dissolve them in 45 mL of deionized water, and stir magnetically for 10 min to obtain a homogeneous, transparent mixed solution; then, weigh 0.45 g of sodium hydroxide and dissolve it in the mixed solution, and stir magnetically for 2 h to generate a homogeneous and stable milky white precursor suspension. Step B: After the obtained milky white precursor suspension was allowed to stand for 1 h to obtain a precipitate, the supernatant was removed. The obtained product was transferred to a 50 mL centrifuge tube. The sample obtained in the centrifuge tube was washed and centrifuged with deionized water and anhydrous ethanol. The collected milky white product was then dried. Step C: Calcine the obtained dried sample at 500℃ in air for 2 h to obtain zinc oxide gas-sensitive material; Step D: Weigh 50 mg of the prepared zinc oxide nanoflower precursor, dissolve it in 25 mL of deionized water, and stir with a magnetic stirrer for 10 min to obtain a uniformly mixed suspension. Then, add a certain amount of tetrachloroauric acid solution to the above solution and stir with a magnetic stirrer for 4 h. Finally, centrifuge the mixed solution in a centrifuge for 5 min. After centrifugation, remove the supernatant and dry the precipitate.

[0022] Step E: The obtained dried sample was calcined at 500℃ for 2 hours in an argon atmosphere to obtain zinc oxide nanoflower gas-sensitive material modified with gold single atoms; Step F: Disperse 25 mg of zinc oxide nanoflower gas-sensitive material modified with gold single atoms in a mortar, add 2 μL of naphthol and 16 μL of terpineol and grind to obtain a viscous slurry, then coat it onto the surface of a planar electrode, and then screen print the electrode surface through a planar electrode printing screen. Excess slurry seeps through the screen and after complete drying, a semiconductor sensor that can be used to detect phosphine gas is constructed.

[0023] The preparation process of the modified gold single-atom zinc oxide nanoflower gas-sensitive material is simple and easy, and the sensor constructed based on the ruthenium single-atom catalyzed indium oxide nanosphere composite gas-sensitive material exhibits high sensitivity, high stability and high selectivity in the detection of hydrogen sulfide gas.

[0024] Example 2 A gold-modified zinc oxide nanoflower gas-sensitive material for phosphine gas sensors is prepared by the method described in the above embodiments. Specifically, the gold-modified zinc oxide nanoflower gas-sensitive material mainly consists of zinc nitrate hexahydrate, and the morphology of the gold-modified zinc oxide nanoflower gas-sensitive material is spherical with a diameter of approximately 3 μm.

[0025] Performance testing During the morphology observation and performance testing of the modified gold single-atom zinc oxide nanoflower composite gas-sensitive material samples prepared in the above embodiments, the following results were obtained: like Figure 1 The image shown is a SEM image prepared in Example 1. Figure 1 The synthesized zinc oxide nanoflowers modified with gold single atoms have a spherical diameter of approximately 3 μm. SEM characterization reveals that the zinc oxide nanoflowers are plate-like with a smooth surface. This structure gives the gold-modified zinc oxide nanoflowers a large specific surface area, increasing the contact area between the gas and the material surface and promoting adsorption and diffusion. The introduction of gold single atoms generates numerous adsorption sites on the zinc oxide surface, thereby enhancing the sensitivity and selectivity for phosphine gas. like Figure 2As shown in the X-ray diffraction (XRD) pattern of the zinc oxide sample, distinct diffraction peaks are clearly visible at the 2θ angles of 31.77°, 34.42°, 36.25°, 47.53°, 51.04°, 56.60°, 62.68°, and 67.96°, corresponding to the (100), (002), (101), (102), (110), (103), and (112) crystal planes of zinc oxide, respectively. The XRD diffraction pattern agrees well with the standard card (JCPDS No. 36-1451), confirming the presence of zinc oxide in the composite sample. Furthermore, no additional diffraction peaks were observed in the sample, indicating its high crystallinity and the absence of impurity peaks.

[0026] Example 3 Application of a modified gold single-atom zinc oxide nanoflower gas-sensitive material for constructing a phosphine gas sensor: This gas-sensitive material can be used for the rapid detection of phosphine gas, specifically: 25 mg of zinc oxide nanoflower gas-sensitive material modified with gold single atoms was dispersed in a mortar, and 2 μL of naphthol and 16 μL of terpineol were added and ground to obtain a viscous slurry. This slurry was then coated onto the surface of a planar electrode and completely dried to form a semiconductor sensor that can be used to detect phosphine gas. In the production process of zinc oxide nanoflower composite gas-sensitive material modified with gold single atoms for use in phosphine gas sensors, the zinc oxide nanoflower composite gas-sensitive material modified with gold single atoms prepared in the above embodiments is used to construct a phosphine gas sensor through a sensor sensitive film coating process. This enables rapid sensing response to phosphine gas and quickly exhibits excellent gas-sensitive characteristics.

[0027] The above-mentioned gas-sensitive application of zinc oxide nanoflowers of the present invention involves dispersing the zinc oxide nanoflower gas-sensitive material in a mortar, adding a certain amount of naphthol and terpineol, and grinding it to obtain a viscous slurry. This slurry is then coated onto the surface of a planar electrode, and subsequently screen-printed onto the electrode surface using a planar electrode printing screen. Excess slurry seeps through the screen and is completely dried to form a gas sensor. After aging for 36 hours, gas-sensitive detection is performed. The sensor is tested for phosphine gas sensitivity at an operating temperature of 275 °C. like Figure 3The figure shows the dynamic response curves of a sensor prepared from a gold-modified zinc oxide nanoflower composite gas-sensitive material to different concentrations (0.1 ppm to 1.2 ppm) of phosphine gas at an operating temperature of 275°C and a humidity of 50%. The figure shows that the sensor with the gold-modified zinc oxide nanoflower composite gas-sensitive material exhibits a response value of 3.07 at 0.1 ppm and reaches 18.09 at 1 ppm, highlighting its excellent sensing performance. Furthermore, the sensitivity of this gas sensor increases with increasing phosphine gas concentration, indicating that the prepared sensor has good reversibility. like Figure 4 The figure shows a bar graph illustrating the response values ​​of a sensor prepared from a gold-modified zinc oxide nanoflower composite gas-sensitive material at a humidity of 50% and an operating temperature of 275°C to nine gases (dimethyl sulfide, carbon disulfide, valeric acid, propionic acid, acetic acid, butyric acid, acetone, trimethylamine, and phosphine) at a concentration of 1 ppm. The graph shows that the sensor prepared from the gold-modified zinc oxide nanoflower composite gas-sensitive material exhibits a good response to phosphine gas.

[0028] In summary, the zinc oxide nanoflower composite gas-sensitive material modified with gold single atoms in this embodiment of the invention exhibits excellent gas-sensing performance at 275°C.

[0029] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for constructing a semiconductor gas sensor for detecting phosphine gas, characterized in that: Includes the following steps: Step A: Dissolve zinc nitrate hexahydrate and sodium citrate dihydrate in deionized water, then add sodium hydroxide to the mixed transparent solution to generate a precursor suspension; Step B: Let the precursor suspension stand, remove the supernatant after the precipitate is obtained, and then wash, centrifuge and dry to obtain the first sample; Step C: Calcine the first sample in air at 500°C for 2 hours to obtain zinc oxide nanoflower-like precursor; Step D: Dissolve the zinc oxide nanoflower precursor in deionized water, then add 25 μL of 20 mg / mL tetrachloroauric acid solution, stir, centrifuge, and dry the precipitate to obtain the second sample; Step E: Calcine the second sample at 500°C for 2 hours in an argon atmosphere to obtain zinc oxide nanoflower gas-sensitive material modified with gold single atoms; Step F: Add naphthol and terpineol to the zinc oxide nanoflower gas-sensitive material modified with gold single atoms and grind it to obtain a viscous slurry. Then coat it onto the surface of the planar electrode and screen print the electrode surface through the planar electrode printing screen. After it is completely dried, a semiconductor sensor is constructed. In step A, the ratio of zinc nitrate hexahydrate, sodium citrate dihydrate, deionized water, and sodium hydroxide is 0.68g:1.58g:45mL:0.45g. In step D, the ratio of zinc oxide nanoflower precursor to deionized water is 50 mg: 25 mL. The modified gold single-atom zinc oxide nanoflower-like composite gas-sensitive material has a spherical morphology with a diameter of 3 μm.

2. The method for constructing a semiconductor gas sensor for detecting phosphine gas according to claim 1, characterized in that: In step F, the amount of zinc oxide nanoflower gas-sensitive material modified with gold single atoms, and the ratio of naphthol to terpineol, are 25 mg: 2 uL: 16 uL.

3. The method for constructing a semiconductor gas sensor for detecting phosphine gas according to claim 2, characterized in that: In steps B and D, the precipitate is dried at a temperature of 60 °C for 12-24 h to remove moisture from the precipitate.

4. The method for constructing a semiconductor gas sensor for detecting phosphine gas according to claim 3, characterized in that: In steps C and E, the heating rate of the dried sample during calcination is 2 °C·min. -1 .

5. The method for constructing a semiconductor gas sensor for detecting phosphine gas according to claim 4, characterized in that: In step B, the obtained milky white precipitate is centrifuged and washed three times at a speed of 8000 rpm for 5 min. In step D, the modified gold single-atom zinc oxide gas-sensitive precursor material is centrifuged and cleaned once at a speed of 8000 rpm for 5 min.

6. The method for constructing a semiconductor gas sensor for detecting phosphine gas according to claim 5, characterized in that: The modified gold single-atom zinc oxide nanoflower-like composite gas-sensitive material of the phosphine gas sensor is mainly composed of zinc nitrate hexahydrate.

7. An application of a zinc oxide nanoflower-like composite gas-sensitive material modified with gold single atoms, characterized in that, The modified gold single-atom zinc oxide nanoflower-like composite gas-sensitive material prepared by the method according to any one of claims 1-6 is dispersed in a mortar, then naphthol and terpineol are added and ground until the mixture is in slurry form, then coated on the surface of a planar electrode by a brush, and then screen-printed on the electrode surface by a planar electrode printing screen. After it is completely dried, a gas sensor is formed and used for phosphine gas sensing test.

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