Tin disulfide / tin oxide / indium oxide ternary composite material as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of semiconductor gas sensors, and discloses a tin disulfide / tin oxide / indium oxide ternary composite material and a preparation method and application thereof.A SnS2 / SnO2 / In2O3 ternary heterojunction system is constructed, the ternary composite material has a unique microflower / nano-particle hierarchical structure, microflower-shaped SnS2-SnO2 provides a high specific surface area and adsorption sites, and the specific surface area and the adsorption sites are high; and small-size In2O3 nanoparticles are uniformly loaded, so that the gas adsorption and catalytic conversion capabilities are enhanced.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of semiconductor gas sensors, and particularly relates to a tin disulfide / tin oxide / indium oxide ternary composite material and a preparation method and application thereof. BACKGROUND

[0002] In modern society, lithium ion batteries have become widely used energy storage media due to their high capacity, high output voltage, high charging rate, high energy density, low self-discharge, excellent cycle characteristics and many other advantages, and occupy an important position in various electrical appliances such as mobile phones and notebook computers, energy storage systems, vehicles and other fields. However, while lithium ion batteries bring convenience, they also pose a safety hazard that cannot be ignored. The electrolyte used in lithium ion batteries is mostly flammable or combustible organic solvents. Under the action of external factors such as overcharging, overdischarging, overheating and mechanical impact, the battery separator is easily damaged, which in turn causes internal short circuit, and ultimately leads to thermal runaway. Once thermal runaway occurs, the temperature of the battery will rise sharply, not only releasing a large amount of smoke, but also possibly triggering thermal runaway of other normal battery cells in the battery pack, ultimately causing a fire or even an explosion.

[0003] Regardless of the type of abuse that leads to lithium battery thermal runaway, at the early stage of thermal runaway, when the internal temperature of the battery is below 300℃, many side reactions will occur inside the battery, leading to a rise in temperature and the production of a large amount of gas. These side reactions are accompanied by the production of a large amount of different gases, including flammable, explosive and toxic gases, and all of these side reactions produce a large amount of heat, ultimately leading to lithium ion battery thermal runaway. The thermal runaway process is rapid and irreversible, and in order to minimize losses, it is crucial to detect and warn of the initial stage of thermal runaway and take timely intervention measures. The lithium ion battery thermal runaway process produces a variety of gases, among which dimethyl carbonate (DMC) is one of the main components of the electrolyte, and its vapor is produced in large quantities at the early stage of thermal runaway, with a concentration much higher than that of other gases, and accounts for the highest proportion of gases produced during thermal runaway. Therefore, detecting DMC vapor has a significant advantage in early warning of lithium battery thermal runaway.

[0004] In order to give an early warning in the early stage of thermal runaway, the key is to develop a high-sensitivity DMC vapor sensor. However, there are few studies on gas-sensitive sensors for DMC vapor at present, and only a few works have reported the detection of DMC vapor. For example, the patent "Sensor for lithium ion battery leakage detection, preparation method and application" uses a nickel-doped nano-zinc oxide material to prepare a gas-sensitive sensor, which realizes the detection of DMC vapor, but the working temperature of the sensor is as high as 300°C. Zhou, KC et al. [Kechen Zhou, Huiyu Su, et al., Exposed (111) Plane Engineered of Lead-Free Perovskite Cs2SnCl6 Octahedra for DMC Sensing in LIB Electrolyte Leakage Detection, Small 2025, 21, 2503337] reported a gas-sensitive sensor based on Cs2SnCl6 material, which has a response of 7.05 to 100 ppm DMC at 200°C.

[0005] It can be seen that the prior art for DMC gas detection has the problems of few sensitive materials, high working temperature and poor sensitivity. SUMMARY

[0006] The purpose of the present application is to solve the problems of the prior art, and provide a tin disulfide / tin oxide / indium oxide ternary composite material, a preparation method and application thereof.

[0007] In order to solve the technical problem, the technical scheme of the present application is: a preparation method of a tin disulfide / tin oxide / indium oxide ternary composite material, comprising the following steps: Step 1: Dissolve tin tetrachloride pentahydrate in anhydrous ethanol, stir until completely dissolved, add thioacetamide and continue stirring to form a precursor solution; the weight ratio of tin tetrachloride pentahydrate to thioacetamide is 1.8-2:1, and the amount ratio of tin tetrachloride pentahydrate to anhydrous ethanol is 0.03g:1-1.5ml; Step 2: Hydrothermal reaction of the precursor solution, centrifugal collection of the product after the reaction, washing and drying to obtain flower-shaped tin disulfide micromaterials; Step 3: the obtained flower-like tin disulfide micromaterial is dispersed in a mixed solvent of deionized water and ethylene glycol, indium chloride, sodium citrate and urea are added, and a secondary hydrothermal reaction is carried out, and after centrifugal cleaning and drying, a tin disulfide powder loaded with indium oxide precursor is obtained; the use amount ratio of the flower-like tin disulfide micromaterial to the mixed solvent is 0.004 g-0.008 g:1 ml, the volume ratio of deionized water to ethylene glycol in the mixed solvent is 1:1, and the weight ratio of the flower-like tin disulfide micromaterial, indium chloride, sodium citrate and urea is 1:1-2:1.5-2.5:2-3.5; Step 4: the tin disulfide powder loaded with indium oxide precursor is subjected to single gradient annealing treatment: in an air atmosphere, the temperature is raised to 250°C at a rate of 1-5°C / min, and then the temperature is raised to 300-450°C at a rate of 1-5°C / min, and the tin disulfide is controlled to be partially oxidized to tin oxide, and the crystallization of indium oxide is completed, and finally a ternary composite material of tin disulfide / tin oxide / indium oxide is formed.

[0008] Preferably, step 1 is specifically: tin tetrachloride pentahydrate is dissolved in anhydrous ethanol, the use amount ratio of tin tetrachloride pentahydrate to anhydrous ethanol is 0.03 g:1 ml, the concentration of anhydrous ethanol is ≥99.7%, and the transparent mixed solution is obtained by magnetic stirring at 600-1000 rpm for 20-40 min until complete dissolution, then thioacetamide is added and the solid is completely dissolved by magnetic stirring at 600-1000 rpm for 30-40 min, and a precursor solution is formed.

[0009] Preferably, step 2 is specifically: the precursor solution obtained in step 1 is loaded into a polytetrafluoroethylene-lined hydrothermal reaction kettle, sealed and placed in an oven, and a hydrothermal reaction is carried out at 170-190°C for 10-14 h, after the reaction is completed, the hydrothermal reaction kettle is naturally cooled to room temperature, the product is taken out, centrifuged at a speed of 6000-9000 r / min for 10-20 min for solid-liquid separation, washed with "ethanol-deionized water-ethanol" alternately for 3 times until the upper clear liquid is neutral, and the washed solid product is placed in a drying oven and dried at 60-80°C for 12-14 h to obtain a flower-like tin disulfide micromaterial.

[0010] Preferably, step 3 is specifically: grinding the obtained flower-shaped tin disulfide micromaterial, dissolving it in a mixed solution of deionized water and ethylene glycol after grinding, the volume ratio of deionized water and ethylene glycol is 1:1, the concentration of ethylene glycol is ≥99%, and the magnetic stirring is carried out at 600-900 rpm for 20-40 min until complete dispersion, indium chloride is added to the above dispersion, and stirring is continued for 20-40 min, then sodium citrate and urea are added, and stirring is carried out for 30-40 min until complete dissolution to obtain a mixed solution, the above mixed solution is loaded into a polytetrafluoroethylene-lined hydrothermal reaction kettle, and a secondary hydrothermal reaction is carried out at 150-170℃ for 24-28 h, after the reaction is completed, the product is separated by centrifugation at a speed of 6000-9000 r / min for 10-20 min, and the "ethanol-deionized water-ethanol" is alternately cleaned for 3 times, and dried in a drying box at 60-80℃ for 12-14 h to obtain a tin disulfide powder loaded with indium oxide precursor.

[0011] Preferably, step 4 is specifically: placing the tin disulfide powder loaded with indium oxide precursor obtained in step 3 into a crucible, placing it into a muffle furnace, and heating it in air at a rate of 1-5℃ / min to 250℃, and keeping it at this temperature for 0.5 h, then heating it at a rate of 1-5℃ / min to 300-400℃, and keeping it at this temperature for 1-2 h to perform annealing treatment, so that part of the tin disulfide is oxidized to tin dioxide, and finally a tin disulfide / tin oxide / indium oxide ternary composite material is obtained.

[0012] Preferably, a tin disulfide / tin oxide / indium oxide ternary composite material is prepared by the preparation method of the tin disulfide / tin oxide / indium oxide ternary composite material, and the ternary composite material prepared by the preparation method has a micron flower-shaped tin disulfide / tin oxide substrate, the petals of which are lamellar structures with a size of 3-8 μm, and indium oxide nanoparticles with a particle size of 20-50 nm are uniformly loaded on the surface of the lamellar structure.

[0013] Preferably, the application of a tin disulfide / tin oxide / indium oxide ternary composite material is that the ternary composite material prepared by the preparation method of the tin disulfide / tin oxide / indium oxide ternary composite material is used for preparing a DMC gas sensitive sensor, the working temperature of the DMC gas sensitive sensor is 180℃, and it is used for detecting DMC vapor.

[0014] Preferably, the preparation method of a DMC gas sensitive sensor comprises the following steps: Step 1: dispersing the ternary composite material and the binder in a mixed solution of ethylene glycol and anhydrous ethanol to prepare a uniform slurry; the weight ratio of the ternary composite material to the binder is 1-3:0.05-0.1, the use amount ratio of the ternary composite material to the mixed solution of ethylene glycol and anhydrous ethanol is 1 g:3-5 ml, and the volume ratio of ethylene glycol to anhydrous ethanol is 1:2-5; Step 2: cleaning and pretreating the interdigital electrode; Step 3: coating the slurry on the surface of the interdigital electrode, drying, soldering and packaging to obtain the DMC gas sensor.

[0015] Preferably, the step 1 is specifically: grinding the ternary composite material, dissolving in the mixed solution of ethylene glycol and anhydrous ethanol after grinding, adding the adhesive polyvinylpyrrolidone to the mixed solution, stirring at 600-900 rpm for 1-3 h, and then ultrasonic dispersion for 5-15 min to prepare a uniform slurry.

[0016] Preferably, the step 2 is specifically: the interdigital electrode is an alumina substrate and a gold electrode, and the interdigital electrode is ultrasonically cleaned in 5-15 ml of anhydrous ethanol, 5-15 ml of deionized water and 5-15 ml of anhydrous ethanol, respectively, for 0.5-1.5 min; Preferably, the step 3 is specifically: using a pipette to take the slurry obtained in step 1 and uniformly drop coating on the surface of the pretreated interdigital electrode, placing in a 25℃ constant temperature box to dry, placing the dried interdigital electrode in an oven for further drying at 60-80℃ for 1-3 h, using a soldering iron and a tin wire to solder the dried interdigital electrode on the sensor base to obtain a DMC gas sensor of a tin disulfide / tin oxide / indium oxide ternary composite material.

[0017] Compared with the prior art, the application has the following advantages: (1) The application discloses a tin disulfide / tin oxide / indium oxide ternary composite material, and constructs a SnS2 / SnO2 / In2O3 ternary heterojunction system. The ternary composite material has a unique micron flower / nanoparticle hierarchical structure. The micron flower-shaped SnS2-SnO2 provides a high specific surface area and adsorption sites, and the small-size In2O3 nanoparticles are uniformly loaded to enhance the gas adsorption and catalytic conversion capacity. (2) The tin disulfide / tin oxide / indium oxide ternary composite material can be used for preparing a DMC gas sensor, and is applied to DMC vapor detection. The working temperature of the DMC gas sensor is as low as 180℃, the power consumption is significantly reduced, and the DMC gas sensor exhibits high sensitivity, high selectivity and humidity resistance. (3) The application discloses a preparation method of a tin disulfide / tin oxide / indium oxide ternary composite material. First, a reaction precursor solution is formed by using tin tetrachloride pentahydrate, then a flower-shaped tin disulfide micron material is obtained through a hydrothermal reaction, then the flower-shaped tin disulfide micron material, indium chloride, sodium citrate and urea are subjected to a secondary hydrothermal reaction to obtain a tin disulfide powder loaded with an indium oxide precursor, and finally the tin disulfide powder loaded with the indium oxide precursor is subjected to single gradient annealing treatment to obtain the tin disulfide / tin oxide / indium oxide ternary composite material. The reaction process has a high synthesis yield and small environmental pollution. (4) The application adopts single gradient annealing process in annealing, simplifies the process, reduces energy consumption, and avoids multiple high-temperature treatments. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 XRD pattern of SnS2 / SnO2 / In2O3 ternary composite material obtained in Example 1 of the application; Figure 2 SEM photos of SnS2 / SnO2 / In2O3 ternary composite material and SnS2 material obtained in Example 2 of the application; Figure 3 Element distribution photo of SnS2 / SnO2 / In2O3 ternary composite material obtained in Example 3 of the application; Figure 4 Response comparison curve of DMC gas sensitive sensor made of SnS2 / SnO2 / In2O3 ternary composite material obtained in Example 4 of the application and SnS2 sensor to 100 ppm DMC at 180℃. DETAILED DESCRIPTION

[0019] The application is described in detail below with reference to the drawings and specific examples, but the application is not limited to these examples only. The application covers any alternatives, modifications, equivalent methods and solutions made within the spirit and scope of the application. In order to make the public have a thorough understanding of the application, specific details are described in the following examples of the application, and the application can also be completely understood without the description of these details for those skilled in the art.

[0020] The application discloses a preparation method of tin disulfide / tin oxide / indium oxide ternary composite material, comprising the following steps: Step 1: Dissolve tin tetrachloride pentahydrate in anhydrous ethanol, stir until completely dissolved, and then add thioacetamide to continue stirring to form a precursor solution; the weight ratio of tin tetrachloride pentahydrate to thioacetamide is 1.8-2:1, and the dosage ratio of tin tetrachloride pentahydrate to anhydrous ethanol is 0.03 g:1-1.5 ml; Step 2: Perform hydrothermal reaction on the precursor solution, collect the product by centrifugation after the reaction is completed, wash and dry to obtain flower-shaped tin disulfide micromaterial; Step 3: Disperse the obtained flower-shaped tin disulfide micromaterial in a mixed solvent of deionized water and ethylene glycol, add indium chloride, sodium citrate and urea, perform secondary hydrothermal reaction, wash by centrifugation and dry to obtain tin disulfide powder loaded with indium oxide precursor; the dosage ratio of the flower-shaped tin disulfide micromaterial to the mixed solvent is 0.004 g-0.008 g:1 ml, the volume ratio of deionized water to ethylene glycol in the mixed solvent is 1:1, and the weight ratio of the flower-shaped tin disulfide micromaterial, indium chloride, sodium citrate and urea is 1:1-2:1.5-2.5:2-3.5; Step 4: Single gradient annealing treatment of the tin disulfide powder loaded with indium oxide precursor: heating at 1-5℃ / min to 250℃ for 0.5h, then heating at 1-5℃ / min to 300-450℃ for 1-2h in an air atmosphere, so that part of the tin disulfide is controllably oxidized to tin oxide, and the crystallization of indium oxide is completed, and finally a tin disulfide / tin oxide / indium oxide ternary composite material is formed.

[0021] Preferably, step 1 is specifically: dissolving tin chloride pentahydrate in anhydrous ethanol, the ratio of tin chloride pentahydrate to anhydrous ethanol being 0.03g:1ml, the concentration of anhydrous ethanol being ≥99.7%, and magnetically stirring at 600-1000rpm for 20-40min until completely dissolved to obtain a transparent mixed solution, then adding thioacetamide and continuing to magnetically stir at 600-1000rpm for 30-40min to ensure complete dissolution of the solid, forming a precursor solution.

[0022] Preferably, step 2 is specifically: loading the precursor solution obtained in step 1 into a polytetrafluoroethylene-lined hydrothermal reaction kettle, sealing it and placing it in an oven, and performing hydrothermal reaction at 170-190℃ for 10-14h, after the reaction is completed, the hydrothermal reaction kettle is naturally cooled to room temperature, the product is taken out, centrifuged at a speed of 6000-9000r / min for 10-20min for solid-liquid separation, washed with "ethanol-deionized water-ethanol" alternately for 3 times until the upper clear liquid is neutral, and the washed solid product is placed in a drying oven at 60-80℃ for 12-14h to obtain flower-like tin disulfide micron material.

[0023] Preferably, step 3 is specifically: grinding the obtained flower-like tin disulfide micron material, dissolving it in a mixed solution of deionized water and ethylene glycol, the volume ratio of deionized water to ethylene glycol being 1:1, the concentration of ethylene glycol being ≥99%, and magnetically stirring at 600-900rpm for 20-40min until completely dispersed, then adding indium chloride to the above dispersion, continuing to stir for 20-40min, then adding sodium citrate and urea, and stirring for 30-40min until completely dissolved to obtain a mixed solution, loading the mixed solution into a polytetrafluoroethylene-lined hydrothermal reaction kettle, and performing secondary hydrothermal reaction at 150-170℃ for 24-28h, after the reaction is completed, centrifuging the product at a speed of 6000-9000r / min for 10-20min, washing with "ethanol-deionized water-ethanol" alternately for 3 times, and drying in a drying oven at 60-80℃ for 12-14h to obtain tin disulfide powder loaded with indium oxide precursor.

[0024] Preferably, step 4 is specifically: placing the tin disulfide powder loaded with indium oxide precursor obtained in step 3 into a crucible, placing it into a muffle furnace, heating it to 250℃ at a rate of 1-5℃ / min in air, keeping it at 250℃ for 0.5h, then heating it to 300-400℃ at a rate of 1-5℃ / min, keeping it at 300-400℃ for 1-2h, to perform annealing treatment, so that part of the tin disulfide is oxidized to tin dioxide, and finally obtain a tin disulfide / tin oxide / indium oxide ternary composite material.

[0025] Preferably, a tin disulfide / tin oxide / indium oxide ternary composite material is prepared by the preparation method of the tin disulfide / tin oxide / indium oxide ternary composite material, and the ternary composite material prepared by the preparation method has a micron-flower-shaped tin disulfide / tin oxide substrate, the petal of the flower is a lamellar structure, the size is 3-8μm, and indium oxide nanoparticles are uniformly loaded on the surface of the lamellar structure, and the particle size is 20-50nm.

[0026] Preferably, the application of a tin disulfide / tin oxide / indium oxide ternary composite material is that the ternary composite material prepared by the preparation method of the tin disulfide / tin oxide / indium oxide ternary composite material is used for preparing a DMC gas sensitive sensor, the working temperature of the DMC gas sensitive sensor is 180℃, and the DMC gas sensitive sensor is used for detecting DMC vapor.

[0027] Preferably, the preparation method of a DMC gas sensitive sensor comprises the following steps: Step 1: dispersing the ternary composite material and the adhesive in a mixed solution of ethylene glycol and anhydrous ethanol to prepare a uniform slurry; the weight ratio of the ternary composite material to the adhesive is 1-3:0.05-0.1, the use amount ratio of the ternary composite material to the mixed solution of ethylene glycol and anhydrous ethanol is 1g:3-5ml, and the volume ratio of ethylene glycol to anhydrous ethanol is 1:2-5; Step 2: washing and pretreating the interdigital electrode; Step 3: coating the slurry on the surface of the interdigital electrode, drying, welding and packaging to obtain the DMC gas sensitive sensor.

[0028] Preferably, step 1 is specifically: grinding the ternary composite material, dissolving it in a mixed solution of ethylene glycol and anhydrous ethanol after grinding, adding the adhesive polyvinylpyrrolidone to the mixed solution, magnetically stirring at 600-900rpm for 1-3h, and then ultrasonic dispersing for 5-15min to prepare a uniform slurry.

[0029] Preferably, step 2 is specifically: the interdigital electrode is an alumina substrate and a gold electrode, and the interdigital electrode is ultrasonically washed in 5-15ml of anhydrous ethanol, 5-15ml of deionized water and 5-15ml of anhydrous ethanol, respectively, for 0.5-1.5min each time; Preferably, the step 3 is specifically: using a pipette to suck the slurry obtained in step 1, uniformly drop coating on the surface of the pretreated interdigital electrode, placing in a 25℃ constant temperature box to dry, placing the dried interdigital electrode in an oven, and further drying at 60~80℃ for 1~3h, so that the slurry forms a dense film, using an electric soldering iron and a tin wire to weld the dried interdigital electrode on the sensor base, to obtain a DMC gas sensitive sensor of SnS2 / SnO2 / In2O3 ternary composite material.

[0030] Example 1 1) Dissolve 1.76g of tin tetrachloride pentahydrate in 60ml of anhydrous ethanol, magnetically stir at 600rpm for 30min until completely dissolved to obtain a transparent mixed solution, then add 0.94g of thioacetamide and continue to magnetically stir at 600rpm for 30min to ensure complete dissolution of the solid, forming a reaction precursor solution; 2) Put the reaction precursor solution obtained in step 1 into a 100ml polytetrafluoroethylene lined hydrothermal reactor, seal it and place it in an oven, and heat it at 180℃ for 12h to carry out the hydrothermal reaction, after the reaction is completed, the reactor is naturally cooled to room temperature, the product is taken out, centrifuged at a speed of 7500r / min for 10min to separate the solid and liquid, and the "ethanol-deionized water-ethanol" alternating cleaning strategy is adopted, each cleaning 3 times (each time centrifuged for 10min), until the upper clear liquid is neutral, and the cleaned solid product is placed in a drying oven at 70℃ for 12h to obtain flower-like tin disulfide micron material; 3) Take 0.366g of the flower-like tin disulfide micron material obtained in step 2 and grind it, then dissolve it in a mixture of 30ml deionized water and 30ml ethylene glycol (volume ratio 1:1), and magnetically stir at 700rpm for 30min until completely dispersed, then add 0.443g of indium chloride to the above dispersion, continue to stir for 30min, then add 0.59g of sodium citrate and 0.8g of urea, and stir for 30min until completely dissolved, put the above mixed solution into a 100ml polytetrafluoroethylene lined hydrothermal reactor, and heat it at 160℃ for 24h to carry out a second hydrothermal reaction, after the reaction is completed, centrifuge the product at a speed of 7000r / min for 10min, and also use the "ethanol-deionized water-ethanol" alternating cleaning strategy for 3 times, and dry it in a drying oven at 60℃ for 12h to obtain a tin disulfide powder loaded with indium oxide precursor; 4) Put the tin disulfide / indium oxide binary precursor powder obtained in step 3 into a crucible, place it in a muffle furnace, heat it in air at a rate of 5℃ / min to 250℃, keep it at this temperature for 0.5h, then heat it at a rate of 5℃ / min to 350℃, keep it at this temperature for 2h, and carry out annealing treatment, finally obtain a tin disulfide / tin oxide / indium oxide ternary composite material; 5) Take 0.1g of the ternary composite material powder obtained in step 4, grind it and dissolve it in a mixed solution of 0.067g of ethylene glycol and 0.233g of anhydrous ethanol. Add 0.01g of PVP to the mixed solution, stir magnetically at 600rpm for 1h, and then ultrasonically disperse for 10min to prepare a uniform slurry. 6) Take a commercial interdigital electrode (material: alumina substrate, gold electrode) and ultrasonically clean it for 1 minute each in 10 ml of anhydrous ethanol, 10 ml of deionized water and 10 ml of anhydrous ethanol. 7) Using a pipette, take 0.1 μL of the slurry obtained in step 5 and evenly drop it onto the surface of the pretreated interdigital electrode. Place it in a constant temperature oven at 25°C to dry. Place the dried electrode in an oven and keep it at 70°C for 1 hour to further dry it, so that the slurry forms a dense film. Use a soldering iron and solder wire to solder the dried interdigital electrode onto the sensor base to obtain a ternary composite gas sensor of tin disulfide / tin oxide / indium oxide.

[0031] like Figure 1 The image shows the XRD pattern of the SnS2 / SnO2 / In2O3 ternary composite material obtained in Example 1 of this application. It can be seen that compared with pure SnS2, the XRD curve of the SnS2 / SnO2 / In2O3 ternary composite material has more characteristic peaks of SnO2 and In2O3, which indicates that it is a three-phase material.

[0032] Example 2 1) Dissolve 1.76g of tin tetrachloride pentahydrate in 88ml of anhydrous ethanol and stir magnetically at 600rpm for 30min until completely dissolved to obtain a transparent mixed solution. Then add 0.88g of thioacetamide and continue stirring magnetically at 1000rpm for 30min to ensure that the solid is completely dissolved to form a reaction precursor solution. 2) The reaction precursor solution obtained in step 1 was placed into a 100ml hydrothermal reactor lined with polytetrafluoroethylene, sealed and placed in an oven. The reactor was kept at 190℃ for 10h for hydrothermal reaction. After the reaction was completed, the reactor was allowed to cool naturally to room temperature. The product was taken out and centrifuged at 7500r / min for 10min for solid-liquid separation. An alternating washing strategy of "ethanol-deionized water-ethanol" was adopted, and each was washed 3 times (centrifuged for 10min each time) until the supernatant was neutral. The washed solid product was placed in a drying oven and dried at 70℃ for 12h to obtain flower-shaped tin disulfide micron material. 3) Take 0.366g of the flower-shaped tin disulfide micron material obtained in step 2 and grind it. After grinding, dissolve it in a mixture of 23ml deionized water and 23ml ethylene glycol (volume ratio 1:1). Stir magnetically at 900rpm for 20min until completely dispersed. Add 0.73g of indium chloride to the above dispersion and continue stirring for 30min. Then add 0.915g of sodium citrate and 1.1g of urea and stir for 30min until completely dissolved. Put the above mixed solution into a 100ml polytetrafluoroethylene-lined hydrothermal reactor and keep it at 160℃ for 24h for a second hydrothermal reaction. After the reaction is completed, centrifuge at 7000r / min for 10min to separate the product. Wash it three times with alternating "ethanol-deionized water-ethanol". Dry it in a drying oven at 60℃ for 12h to obtain tin disulfide powder loaded with indium oxide precursor. 4) Place the tin disulfide / indium oxide binary precursor powder obtained in step 3 into a crucible, put it into a muffle furnace, heat it to 250°C in air at a rate of 5°C / min, hold it for 0.5h, then heat it to 350°C at a rate of 5°C / min, hold it for 2h, and perform annealing treatment to finally obtain the tin disulfide / tin oxide / indium oxide ternary composite material. 5) Take 0.1g of the ternary composite material powder obtained in step 4, grind it and dissolve it in a mixed solution of 0.05g ethylene glycol and 0.25g anhydrous ethanol. Add 0.01g PVP to the mixed solution, stir magnetically at 600rpm for 1h, and then ultrasonically disperse for 10min to prepare a uniform slurry. 6) Take a commercial interdigital electrode (material: alumina substrate, gold electrode) and ultrasonically clean it for 1 minute each in 10 ml of anhydrous ethanol, 10 ml of deionized water and 10 ml of anhydrous ethanol. 7) Use a pipette to take 0.1 μL of the slurry obtained in step 5 and evenly drop it onto the surface of the pretreated interdigital electrode. Place it in a constant temperature oven at 25°C to dry. Place the dried electrode in an oven and keep it at 70°C for 1 hour to further dry it so that the slurry forms a dense film. Use a soldering iron and solder wire to solder the dried interdigital electrode onto the sensor base to obtain a ternary composite gas sensor of tin disulfide / tin oxide / indium oxide. like Figure 2 The image shown is a SEM image of the SnS2 / SnO2 / In2O3 ternary composite material and the SnS2 material obtained in Example 2 of this application. Figure 2 Images (a) and (b) are SEM images of tin disulfide powder. Figure 2The SEM photos of the tin disulfide / tin oxide / indium oxide powder in (c) and (d) can be seen that the surface of the pure SnS2 material is relatively smooth, and compared with the SnS2 / SnO2 / In2O3 ternary composite material, it can be seen that the surface of the SnS2 / SnO2 / In2O3 ternary composite material has many small particles, which are In2O3 nanoparticles, the ternary composite material has a micron-flower SnS2-SnO2 substrate with a size of 3-8 μm, the petals thereof are sheet structure, and the In2O3 nanoparticles are uniformly loaded on the surface of the sheet structure with a particle size distribution of 20-50 nm.

[0033] Example 3 1) 1.76 g of tin tetrachloride pentahydrate was dissolved in 60 ml of anhydrous ethanol, and was stirred at 600 rpm for 30 min until completely dissolved to obtain a transparent mixed solution, and then 0.94 g of thioacetamide was added and was continuously stirred at 600-1000 rpm for 30 min to ensure complete dissolution of the solid, thereby forming a reaction precursor solution; 2) The reaction precursor solution obtained in step 1 was loaded into a 100 ml polytetrafluoroethylene-lined hydrothermal reactor, and after sealing, was placed in an oven and was incubated at 180℃ for 12 h to perform a hydrothermal reaction. After the reaction was completed, the reactor was naturally cooled to room temperature, and the product was taken out and was centrifuged at a speed of 7500 r / min for 10 min to perform solid-liquid separation. An “ethanol-deionized water-ethanol” alternating cleaning strategy was adopted, and each cleaning was performed for 3 times (each time for 10 min), until the upper clear liquid was neutral. The cleaned solid product was placed in a drying box and was dried at 70℃ for 12 h to obtain a flower-shaped tin disulfide micron material; 3) 0.366 g of the flower-shaped tin disulfide micron material obtained in step 2 was ground and was dissolved in a mixed solution of 30 ml of deionized water and 30 ml of ethylene glycol (volume ratio 1:1) after grinding. The solution was stirred at 700 rpm for 30 min until completely dispersed. 0.666 g of indium chloride was added to the above dispersion, and was continuously stirred for 30 min. Then, 0.885 g of sodium citrate and 1.2 g of urea were added, and were stirred for 30 min until completely dissolved. The above mixed solution was loaded into a 100 ml polytetrafluoroethylene-lined hydrothermal reactor, and was incubated at 160℃ for 24 h to perform a second hydrothermal reaction. After the reaction was completed, the product was separated by centrifugation at a speed of 7000 r / min for 10 min. Similarly, an “ethanol-deionized water-ethanol” alternating cleaning strategy was adopted, and each cleaning was performed for 3 times. The product was dried in a drying box at 80℃ for 12 h to obtain a tin disulfide powder loaded with an indium oxide precursor; 4) The tin disulfide / indium oxide binary precursor powder obtained in step 3 was placed in a crucible and was placed in a muffle furnace. The temperature was increased to 250℃ at a rate of 2℃ / min in air, and was incubated for 0.5 h. Then, the temperature was increased to 450℃ at a rate of 5℃ / min, and was incubated for 1 h to perform an annealing treatment. Finally, a tin disulfide / tin oxide / indium oxide ternary composite material was obtained. 5)Take 0.1 g of the ternary composite powder obtained in step 4, grind and dissolve in a mixed solution of 0.067 g of ethylene glycol and 0.233 g of anhydrous ethanol, add 0.01 g of PVP to the mixed solution, stir at 600 rpm for 1 h, and then ultrasonic dispersion for 10 min to prepare a uniform slurry; 6)Take a commercial interdigital electrode (material: alumina substrate, gold electrode), and ultrasonically clean it in 10 ml of anhydrous ethanol, 10 ml of deionized water, and 10 ml of anhydrous ethanol, respectively, for 1 min each; 7)Use a pipette to take 0.1 μL of the slurry obtained in step 5, and evenly drop it on the surface of the pretreated interdigital electrode, place it in a 25°C constant temperature box to dry, and then place the dried electrode in an oven at 70°C for 1 h for further drying, so that the slurry forms a dense film. Use an electric soldering iron and a tin wire to weld the dried interdigital electrode to the sensor base to obtain a tin disulfide / tin oxide / indium oxide ternary composite gas sensitive sensor; As shown in Figure 3 SnS 2 / Elemental distribution image of SnO2 / In2O3 ternary composite, Figure 3 (a) is an electron image 1 of the entire micrometer flower, Figure 3 (b), (c), (d), and (e) are distribution maps of O, Sn, In, and S elements on (a), respectively. It can be seen that In and O elements are uniformly distributed on the entire micrometer flower, indicating that In2O3 nanoparticles are uniformly distributed.

[0034] Example 4 1)Dissolve 1.76 g of tin tetrachloride pentahydrate in 60 ml of anhydrous ethanol, stir at 600 rpm for 30 min until completely dissolved to obtain a transparent mixed solution, then add 0.94 g of thioacetamide and continue to stir at 800 rpm for 30 min to ensure complete dissolution of the solid, forming a reaction precursor solution; 2)Put the reaction precursor solution obtained in step 1 into a 100 ml polytetrafluoroethylene-lined hydrothermal reactor, seal it and place it in an oven at 180°C for 12 h for hydrothermal reaction. After the reaction is completed, the reactor is naturally cooled to room temperature, and the product is taken out and centrifuged at 7000 r / min for 10 min for solid-liquid separation. The "ethanol-deionized water-ethanol" alternating cleaning strategy is adopted, and each cleaning is 3 times (each time centrifuged for 10 min), until the upper clear liquid is neutral. The cleaned solid product is placed in a drying oven at 70°C for 12 h to obtain a flower-shaped tin disulfide micromaterial; 3) Take 0.366 g of the flower-shaped tin disulfide micromaterial obtained in step 2 and grind it, then dissolve it in a mixture of 30 ml of deionized water and 30 ml of ethylene glycol (volume ratio 1:1), and stir it at 700 rpm for 30 min until it is completely dispersed, then add 0.366 g of indium chloride to the above dispersion, continue stirring for 30 min, then add 0.549 g of sodium citrate and 0.732 g of urea, and stir for 30 min until they are completely dissolved, then pour the above mixed solution into a 100 ml polytetrafluoroethylene-lined hydrothermal reaction kettle, and perform a second hydrothermal reaction at 160°C for 24 h, after the reaction is completed, centrifuge the product at a speed of 7000 r / min for 10 min, and wash it with ethanol-deionized water-ethanol alternately for 3 times, and then dry it in a drying box at 60°C for 12 h, to obtain a tin disulfide powder loaded with indium oxide precursors; 4) Put the tin disulfide / indium oxide binary precursor powder obtained in step 3 into a crucible, and place it in a muffle furnace, and heat it in air at a rate of 5°C / min to 250°C, and keep it at this temperature for 0.5 h, then heat it at a rate of 5°C / min to 400°C, and keep it at this temperature for 1.5 h, to perform an annealing treatment, and by precisely controlling the annealing temperature and time, part of the tin disulfide is oxidized to tin dioxide, and finally a tin disulfide / tin oxide / indium oxide ternary composite material is obtained; 5) Take 0.1 g of the ternary composite material powder obtained in step 4, grind it, and then dissolve it in a mixed solution of 0.16 g of ethylene glycol and 0.34 g of anhydrous ethanol, add 0.01 g of PVP to the mixed solution, and stir it at 600 rpm for 1 h, and then ultrasonically disperse it for 10 min, to prepare a uniform slurry; 6) Take a commercial interdigital electrode (material: alumina substrate, gold electrode), and ultrasonically clean it in 10 ml of anhydrous ethanol, 10 ml of deionized water, and 10 ml of anhydrous ethanol, respectively, for 1 min each time; Use a pipette to take 0.1 μL of the slurry obtained in step 5, and evenly drop coat it on the surface of the pretreated interdigital electrode, place it in a 25°C constant temperature box to dry, place the dried electrode in an oven, and keep it at 70°C for 1 h for further drying, so that the slurry forms a dense film, use an electric soldering iron and tin wire to weld the dried interdigital electrode on the sensor base, and obtain a tin disulfide / tin oxide / indium oxide ternary composite material gas sensitive sensor.

[0035] As shown in Figure 4 Figure 4, the response of the DMC gas sensitive sensor made of the SnS 2 / The response of the DMC gas sensitive sensor made of the SnS2 sensor to 100 ppm DMC at 180°C is 15.6, which is significantly better than the SnS2 sensor, and also better than other existing sensors.

[0036] The application discloses a tin disulfide / tin oxide / indium oxide ternary composite material, and constructs a SnS 2 / SnO2 / In2O3 ternary heterojunction system, the ternary composite material has a unique micron flower / nanoparticle hierarchical structure, micron flower-shaped SnS2-SnO2 provides a high specific surface area and adsorption sites, small size In2O3 nanoparticles are uniformly loaded, and gas adsorption and catalytic conversion capacity is enhanced.

[0037] The tin disulfide / tin oxide / indium oxide ternary composite material can be used for preparing a DMC gas sensitive sensor, is applied to DMC vapor detection, the DMC gas sensitive sensor has a working temperature as low as 180 DEG C, power consumption is significantly reduced, and high sensitivity, high selectivity and humidity resistance are shown to DMC vapor.

[0038] The application discloses a preparation method of a tin disulfide / tin oxide / indium oxide ternary composite material, first, a reaction precursor solution is formed by using tin tetrachloride pentahydrate, then flower-shaped tin disulfide micromaterial is obtained through a hydrothermal reaction, then the flower-shaped tin disulfide micromaterial, indium chloride, sodium citrate and urea are subjected to secondary hydrothermal reaction to obtain tin disulfide powder loaded with an indium oxide precursor, finally, the tin disulfide powder loaded with the indium oxide precursor is subjected to single gradient annealing treatment to obtain the tin disulfide / tin oxide / indium oxide ternary composite material, the reaction process has high synthesis yield and small environmental pollution.

[0039] The application adopts single gradient annealing process during annealing, simplifies a process, reduces energy consumption, and avoids multiple high-temperature treatments.

[0040] The preferred embodiments of the application are described in detail above, but the application is not limited to the above-described embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the purpose of the application.

[0041] Many other changes and modifications can be made without departing from the concept and scope of the application. It should be understood that the application is not limited to the specific embodiments, and the scope of the application is defined by the appended claims.

Claims

1. A method for producing a tin disulfide / tin oxide / indium oxide ternary composite material, characterized by, The method comprises the following steps: Step 1: dissolve tin tetrachloride pentahydrate in anhydrous ethanol, stir until completely dissolved, add thioacetamide and continue stirring to form a precursor solution; the weight ratio of tin tetrachloride pentahydrate to thioacetamide is 1.8-2:1, and the amount ratio of tin tetrachloride pentahydrate to anhydrous ethanol is 0.03g:1-1.5ml; Step 2: hydrothermal reaction is carried out on the precursor solution, the product is collected by centrifugation after the reaction is completed, and then washed and dried to obtain a flower-shaped tin disulfide micromaterial; Step 3: the flower-shaped tin disulfide micromaterial is dispersed in a mixed solvent of deionized water and ethylene glycol, indium chloride, sodium citrate and urea are added, and a secondary hydrothermal reaction is carried out, and then the product is washed by centrifugation and dried to obtain a tin disulfide powder loaded with an indium oxide precursor; the amount ratio of the flower-shaped tin disulfide micromaterial to the mixed solvent is 0.004g-0.008g:1ml, the volume ratio of deionized water to ethylene glycol in the mixed solvent is 1:1, and the weight ratio of the flower-shaped tin disulfide micromaterial, indium chloride, sodium citrate and urea is 1:1-2:1.5-2.5:2-3.5; Step 4: the tin disulfide powder loaded with the indium oxide precursor is subjected to single gradient annealing treatment: in an air atmosphere, the temperature is raised to 250℃ at a rate of 1-5℃ / min, and then the temperature is raised to 300-450℃ at a rate of 1-5℃ / min, and the tin disulfide is partially oxidized to tin oxide, and the crystallization of indium oxide is completed, and finally a ternary composite material of tin disulfide / tin oxide / indium oxide is formed.

2. The method for preparing a tin disulfide / tin oxide / indium oxide ternary composite material according to claim 1, characterized in that, The step 1 is specifically: tin tetrachloride pentahydrate is dissolved in anhydrous ethanol, the amount ratio of tin tetrachloride pentahydrate to anhydrous ethanol is 0.03g:1ml, the concentration of anhydrous ethanol is ≥99.7%, and the transparent mixed solution is obtained by magnetic stirring at 600-1000rpm for 20-40min until completely dissolved, then thioacetamide is added and the solid is completely dissolved by magnetic stirring at 600-1000rpm for 30-40min, and a precursor solution is formed.

3. The method for preparing a ternary composite material of tin disulfide / tin oxide / indium oxide according to claim 1, characterized in that, The step 2 is specifically: the precursor solution obtained in step 1 is loaded into a polytetrafluoroethylene-lined hydrothermal reaction kettle, sealed and placed in an oven, and hydrothermal reaction is carried out at 170-190℃ for 10-14h, after the reaction is completed, the hydrothermal reaction kettle is naturally cooled to room temperature, the product is taken out, and solid-liquid separation is carried out by centrifugation at a speed of 6000-9000r / min for 10-20min, the upper clear liquid is washed with "ethanol-deionized water-ethanol" alternately for 3 times until it is neutral, and the washed solid product is placed in a drying oven and dried at 60-80℃ for 12-14h to obtain a flower-shaped tin disulfide micromaterial.

4. The method for preparing a ternary composite material of tin disulfide / tin oxide / indium oxide according to claim 1, characterized in that, The step 3 is specifically: grinding the obtained flower-shaped tin disulfide micromaterial, dissolving in a mixed solution of deionized water and ethylene glycol after grinding, the volume ratio of deionized water to ethylene glycol is 1:1, the concentration of ethylene glycol is greater than or equal to 99%, and the magnetic stirring is carried out at 600-900 rpm for 20-40 min until complete dispersion, indium chloride is added to the above dispersion, and the stirring is continued for 20-40 min, then sodium citrate and urea are added, and the stirring is carried out for 30-40 min until complete dissolution to obtain a mixed solution, the above mixed solution is loaded into a polytetrafluoroethylene-lined hydrothermal reaction kettle, the secondary hydrothermal reaction is carried out at 150-170℃ for 24-28 h, after the reaction is completed, the product is separated by centrifugation at a speed of 6000-9000 r / min for 10-20 min, the "ethanol-deionized water-ethanol" is alternately cleaned for 3 times, and the product is dried in a drying box at 60-80℃ for 12-14 h to obtain a tin disulfide powder loaded with indium oxide precursor.

5. The method for preparing a ternary composite material of tin disulfide / tin oxide / indium oxide according to claim 1, characterized in that, The step 4 is specifically: the tin disulfide powder loaded with indium oxide precursor obtained in step 3 is placed in a crucible and put into a muffle furnace, the temperature is raised to 250℃ at a rate of 1-5℃ / min in air, and the temperature is kept for 0.5 h, then the temperature is raised to 300-400℃ at a rate of 1-5℃ / min, and the annealing treatment is carried out for 1-2 h, so that part of the tin disulfide is oxidized to tin dioxide, and finally the ternary composite material of tin disulfide / tin oxide / indium oxide is obtained.

6. A tin disulfide / tin oxide / indium oxide ternary composite, characterized by, The ternary composite material prepared by the preparation method of the ternary composite material of tin disulfide / tin oxide / indium oxide according to any one of claims 1-5 has a micron flower-shaped tin disulfide / tin oxide substrate, the petal is a sheet structure, the size is 3-8 μm, and the indium oxide nanoparticles are uniformly loaded on the surface of the sheet structure with a particle size of 20-50 nm.

7. Use of a tin disulfide / tin oxide / indium oxide ternary composite, characterized in that The ternary composite material prepared by the preparation method of the ternary composite material of tin disulfide / tin oxide / indium oxide according to any one of claims 1-5 is used for preparing a DMC gas sensitive sensor, the working temperature of the DMC gas sensitive sensor is 180℃, and the DMC gas sensitive sensor is used for detecting DMC vapor.

8. Use of a tin disulfide / tin oxide / indium oxide ternary composite according to claim 7, characterized in that The preparation method of the DMC gas sensitive sensor comprises the following steps: Step 1: dispersing the ternary composite material and the binder in a mixed solution of ethylene glycol and anhydrous ethanol to prepare a uniform slurry; the weight ratio of the ternary composite material to the binder is 1-3:0.05-0.1, the use amount ratio of the ternary composite material to the mixed solution of ethylene glycol and anhydrous ethanol is 1 g:3-5 ml, and the volume ratio of ethylene glycol to anhydrous ethanol is 1:2-5; Step 2: washing and pretreating the interdigital electrode; Step 3: coating the slurry on the surface of the interdigital electrode, drying, welding and packaging to obtain the DMC gas sensitive sensor.

9. Use of a tin disulfide / tin oxide / indium oxide ternary composite according to claim 8, characterized in that The step 1 is specifically: grinding the ternary composite material, dissolving in a mixed solution of ethylene glycol and anhydrous ethanol after grinding, adding the binder polyvinylpyrrolidone to the mixed solution, and stirring at 600-900 rpm for 1-3 h, and then ultrasonic dispersion for 5-15 min to prepare a uniform slurry.

10. Use of a tin disulfide / tin oxide / indium oxide ternary composite according to claim 8, characterized in that, The step 2 is specifically: the interdigital electrode is an aluminum oxide substrate and a gold electrode, and the interdigital electrode is sequentially cleaned in 5-15 ml of anhydrous ethanol, 5-15 ml of deionized water and 5-15 ml of anhydrous ethanol for 0.5-1.5 min by ultrasonic cleaning; the step 3 is specifically: the slurry obtained in the step 1 is taken by using a pipette, is uniformly drop-coated on the surface of the pretreated interdigital electrode, is placed in a 25℃ constant-temperature box for air-drying, the interdigital electrode after air-drying is placed in an oven for further drying at 60-80℃ for 1-3 h, the slurry is formed into a dense film, and the interdigital electrode after drying is welded on a sensor base by using an electric soldering iron and a tin wire, so that a DMC gas sensitive sensor of a tin disulfide / tin oxide / indium oxide ternary composite material is obtained.

Images