Stannic oxide hollow porous film gas sensitive element and preparation method thereof

Abstract

The invention discloses a stannic oxide hollow porous film gas sensitive element and a preparation method thereof. The gas sensitive element is characterized by covering a thin film formed by a single-layer stannic oxide hollow sphere on a substrate accompanied by an electrode, wherein the thickness of the thin film is 90 to 130nm, the diameter of the hollow sphere is 90 to 130nm, the wall thickness is 15 to 25nm, the diameter of each particle forming a sphere wall is 15 to 25nm, and the pore space between each two particles is 2 to 4nm. The method comprises the steps of adding stannic chloride pentahydrate into an ethanol water, stirring, adding a hydrochloric acid solution to obtain a mixed liquor, carrying out sealed reaction on the mixed liquor, carrying out solid-liquid separation on the mixed liquor, and washing to obtain a stannic oxide hollow sphere; adding a mercapto-type modifier into a stannic oxide hollow sphere ethyl alcohol dispersion liquid, stirring, carrying out solid-liquid separation, and washing to obtain mercapto-modified stannic oxide hollow sphere; adopting an air-water interface self-assembly method for self-assembling the mercapto-modified stannic oxide hollow sphere on a water surface so as to obtain a single-layer stannic oxide hollow sphere thin film, using the substrate accompanied by the electrode for fishing out, and drying to obtain a target product. The stannic oxide hollow porous film gas sensitive element is easy to be widely used in high sensitivity trace detection of methyl mercaptan gas.

Description

technical field

[0001] The invention relates to a gas sensor and a preparation method, in particular to a tin oxide hollow porous film gas sensor and a preparation method thereof. Background technique

[0002] Methyl mercaptan is a kind of volatile organic sulfide, and it will cause greater damage to the human respiratory system and nervous system at a lower concentration (>0.5ppm). This highly toxic organic sulfide is widely found in sewage treatment, petroleum refining, pulp industry and energy-related treatment processes.

[0003] Tin oxide (SnO 2 ) is an important n-type semiconductor, which has been widely used in solar cells, catalytic support materials, chemical sensors and other fields. With the development of nanoscience and technology, in order to make tin oxide have better sensing performance, people have synthesized tin oxide nanomaterials with various shapes, such as the title "NO 2 Sensing performance of SnO 2 hollow-spheres sensor", Sensor and Actuators...

Examples

Embodiment 1

[0040] The concrete steps of preparation are:

[0041] Step 1, according to the weight ratio of tin tetrachloride pentahydrate, 5vol% ethanol aqueous solution and 40wt% hydrochloric acid solution is 0.5:150:1, first add tin tetrachloride pentahydrate into ethanol aqueous solution and stir for 10 minutes, A hydrochloric acid solution was added thereto to obtain a mixed solution. Then place the mixed solution at 150°C for 24 hours of airtight reaction, and then carry out solid-liquid separation and washing treatment; wherein, the solid-liquid separation treatment is centrifugation, the rotation speed is 6000r / min, the time is 6min, and the washing treatment is to use The deionized water and ethanol alternately wash the separated solid matter twice, and the separation of the solid matter during cleaning is centrifugal separation to obtain tin oxide hollow spheres.

[0042] Step 2, first disperse the tin oxide hollow spheres in ethanol to obtain a 10 g / L tin oxide hollow sphere e...

Embodiment 2

[0045] The concrete steps of preparation are:

[0046] Step 1, according to the weight ratio of tin tetrachloride pentahydrate, 16vol% ethanol aqueous solution and 39wt% hydrochloric acid solution is 0.58:125:1, first add tin tetrachloride pentahydrate into ethanol aqueous solution and stir for 15 minutes, A hydrochloric acid solution was added thereto to obtain a mixed solution. Then place the mixed solution at 163°C for 19.3 hours in closed reaction, and then carry out solid-liquid separation and washing treatment; wherein, the solid-liquid separation treatment is centrifugation, the rotation speed is 7000r / min, the time is 5.5min, and the washing treatment In order to use deionized water and ethanol to carry out 2 alternate cleanings on the separated solid matter, the separation of the solid matter during cleaning is centrifugal separation to obtain tin oxide hollow spheres.

[0047] Step 2, first disperse the tin oxide hollow spheres in ethanol to obtain a 15 g / L tin oxid...

Embodiment 3

[0050] The concrete steps of preparation are:

[0051] Step 1, according to the weight ratio of tin tetrachloride pentahydrate, 28vol% ethanol aqueous solution and 38wt% hydrochloric acid solution is 1.25:100:1, first add tin tetrachloride pentahydrate into ethanol aqueous solution and stir for 20min, A hydrochloric acid solution was added thereto to obtain a mixed solution. Then place the mixed solution at 175°C for 14.5 hours in a closed reaction, and then carry out solid-liquid separation and washing treatment; wherein, the solid-liquid separation treatment is centrifugation, the rotation speed is 8000r / min, the time is 5min, and the washing treatment is The separated solid matter was alternately washed three times with deionized water and ethanol, and the separation of the solid matter during washing was centrifuged to obtain tin oxide hollow spheres.

[0052] Step 2, first disperse the tin oxide hollow spheres in ethanol to obtain a 20 g / L tin oxide hollow sphere ethanol...

technical field

[0001] The invention relates to a gas sensor and a preparation method, in particular to a tin oxide hollow porous film gas sensor and a preparation method thereof. Background technique

[0002] Methyl mercaptan is a kind of volatile organic sulfide, and it will cause greater damage to the human respiratory system and nervous system at a lower concentration (>0.5ppm). This highly toxic organic sulfide is widely found in sewage treatment, petroleum refining, pulp industry and energy-related treatment processes.

[0003] Tin oxide (SnO 2 ) is an important n-type semiconductor, which has been widely used in solar cells, catalytic support materials, chemical sensors and other fields. With the development of nanoscience and technology, in order to make tin oxide have better sensing performance, people have synthesized tin oxide nanomaterials with various shapes, such as the title "NO 2 Sensing performance of SnO 2 hollow-spheres sensor", Sensor and Actuators...

Examples

Embodiment 1

[0040] The concrete steps of preparation are:

[0041] Step 1, according to the weight ratio of tin tetrachloride pentahydrate, 5vol% ethanol aqueous solution and 40wt% hydrochloric acid solution is 0.5:150:1, first add tin tetrachloride pentahydrate into ethanol aqueous solution and stir for 10 minutes, A hydrochloric acid solution was added thereto to obtain a mixed solution. Then place the mixed solution at 150°C for 24 hours of airtight reaction, and then carry out solid-liquid separation and washing treatment; wherein, the solid-liquid separation treatment is centrifugation, the rotation speed is 6000r / min, the time is 6min, and the washing treatment is to use The deionized water and ethanol alternately wash the separated solid matter twice, and the separation of the solid matter during cleaning is centrifugal separation to obtain tin oxide hollow spheres.

[0042] Step 2, first disperse the tin oxide hollow spheres in ethanol to obtain a 10 g / L tin oxide hollow sphere e...

Embodiment 2

[0045] The concrete steps of preparation are:

[0046] Step 1, according to the weight ratio of tin tetrachloride pentahydrate, 16vol% ethanol aqueous solution and 39wt% hydrochloric acid solution is 0.58:125:1, first add tin tetrachloride pentahydrate into ethanol aqueous solution and stir for 15 minutes, A hydrochloric acid solution was added thereto to obtain a mixed solution. Then place the mixed solution at 163°C for 19.3 hours in closed reaction, and then carry out solid-liquid separation and washing treatment; wherein, the solid-liquid separation treatment is centrifugation, the rotation speed is 7000r / min, the time is 5.5min, and the washing treatment In order to use deionized water and ethanol to carry out 2 alternate cleanings on the separated solid matter, the separation of the solid matter during cleaning is centrifugal separation to obtain tin oxide hollow spheres.

[0047] Step 2, first disperse the tin oxide hollow spheres in ethanol to obtain a 15 g / L tin oxid...

Embodiment 3

[0050] The concrete steps of preparation are:

[0051] Step 1, according to the weight ratio of tin tetrachloride pentahydrate, 28vol% ethanol aqueous solution and 38wt% hydrochloric acid solution is 1.25:100:1, first add tin tetrachloride pentahydrate into ethanol aqueous solution and stir for 20min, A hydrochloric acid solution was added thereto to obtain a mixed solution. Then place the mixed solution at 175°C for 14.5 hours in a closed reaction, and then carry out solid-liquid separation and washing treatment; wherein, the solid-liquid separation treatment is centrifugation, the rotation speed is 8000r / min, the time is 5min, and the washing treatment is The separated solid matter was alternately washed three times with deionized water and ethanol, and the separation of the solid matter during washing was centrifuged to obtain tin oxide hollow spheres.

[0052] Step 2, first disperse the tin oxide hollow spheres in ethanol to obtain a 20 g / L tin oxide hollow sphere ethanol...

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