A tin-zinc oxide composite material sensor

Abstract

A tin-zinc oxide composite material sensor relates to the field of gas sensor technology, particularly a gas sensor material comprising a highly moisture-resistant gas-sensitive material and its preparation method. The preparation method includes the following steps: a. ultrasonic treatment; b. autoclave heating; c. obtaining zinc oxide nanoparticles; d. magnetic stirring; e. autoclave heating; f. obtaining a tin-zinc oxide composite material; g. cleaning and air drying; h. preparing a paste-like slurry; and i. low-temperature drying to complete the fabrication of a planar gas sensor. The gas sensor provided by the present invention offers high accuracy and simple operation. The inclusion of the highly moisture-resistant nano-gas-sensitive material helps address the low sensitivity of metal oxide semiconductor gas sensors in transformer oil and their susceptibility to moisture molecules in the air.

Description

Technical Field

[0001] The present invention relates to the technical field of gas sensors, and in particular to a gas sensor material comprising a highly moisture-resistant gas-sensitive material and a preparation method thereof. Background Art

[0002] Compared to single-component metal oxides, multi-component metal oxides offer abundant raw material resources, low cost, and higher specific capacity. Their diverse elemental composition leads to diverse properties and performance. Tin-zinc oxides, a class of ternary compounds, exhibit superior optical properties, higher electron mobility, and higher conductivity than single-component metal oxides, making them suitable for lithium battery anode materials, photocatalysts, sensors, and solar cells. Researchers are actively studying these ternary compounds to achieve controllable nanostructuring, thereby improving their electrical and optical properties. However, the synthesis of nanostructured ternary compounds is often costly and requires high-precision equipment. To this end, researchers have made significant progress in the physicochemical properties of ternary compounds through optimizing experimental conditions, metal doping, and surfactant modification. Currently, various ternary compound nanomaterials have been grown using various synthesis methods to produce materials with diverse morphologies, such as flowers, nanospheres, nanorods / wires, nanoboxes, and nanosheets.

[0003] Operating sensors are exposed to ambient humidity for extended periods, significantly impacting their performance. Normal ambient air humidity is typically between 40% and 70%. Water vapor molecules adsorb on the surface of the gas-sensing material, competing with the target gas to be detected. This can severely impact the proper functioning of the gas-sensing reaction and even lead to false alarms. Therefore, it is crucial to develop highly moisture-resistant gas-sensing materials for the fabrication of highly sensitive gas sensors. Summary of the Invention

[0004] The present invention discloses a gas sensor material with high moisture resistance and a method for preparing the same. The gas sensor provided by the present invention is highly accurate and easy to operate. The highly moisture-resistant nano-gas-sensitive material helps address the low sensitivity of metal oxide semiconductor gas sensors in transformer oil and their susceptibility to moisture molecules in the air.

[0005] The method for preparing a tin-zinc oxide composite material sensor is characterized in that the tin-zinc oxide composite material sensor is prepared according to the following method:

[0006] a. Zinc oxide was mixed with deionized water in a certain proportion, sodium hydroxide was added to deionized water in a certain proportion with zinc oxide, magnetic stirring was performed at 500 rpm for 30 min, and ultrasonic treatment was performed for 30 min;

[0007] b. The above solution was poured into an autoclave and heated at 200 ° C for 15h. The temperature increased linearly at a certain temperature during the heating process;

[0008] c. After cooling, the mixture was transferred to a centrifuge tube, washed with deionized water and anhydrous ethanol, and dried at a certain temperature to obtain the zinc oxide nanoparticles;

[0009] d. Tin tetrachloride pentahydrate was mixed with deionized water in a certain proportion, sodium hydroxide was added, the pH was 10-11, and magnetic stirring was performed at 500 rpm for 30 min;

[0010] e. The obtained precipitate was dissolved in deionized water and stirred with zinc oxide nanoparticles to form a solution, which was heated in an autoclave at 200 ° C for 12 h, with the temperature increasing linearly at a certain temperature during the heating process;

[0011] f. After cooling, the precipitate was centrifuged and washed repeatedly with deionized water and anhydrous ethanol by centrifugation, and the precipitate was dried at a certain temperature to obtain a tin-zinc oxide composite material;

[0012] g. The ceramic insulating layer of the electrode layer is placed in a beaker containing an appropriate amount of trichloroethylene solution, and then the beaker is placed in an ultrasonic oscillator and kept oscillating for 30 minutes. After that, it is washed twice with anhydrous ethanol and deionized water, respectively, and then dried in the shade;

[0013] h. Take an appropriate amount of nanopowder as a gas-sensitive material and grind it into agate. After grinding thoroughly, add an appropriate amount of deionized water and anhydrous ethanol to form a uniformly mixed paste.

[0014] i. Use a coating pen to evenly apply the prepared gas-sensitive material slurry on the ceramic insulating layer where the signal electrode layer is provided, so that at least a portion of the signal electrode layer and the ceramic insulating layer are coated with the gas-sensitive material layer. After the gas-sensitive material slurry is applied, place the sensor in an oven for low-temperature drying to complete the production of the planar gas sensor.

[0015] Furthermore, the mass ratio of zinc oxide to deionized water is 1:3-1:4, and the mass ratio of zinc oxide to hydroxide is 1:2-1:5.

[0016] Furthermore, the mass ratio of tin tetrachloride pentahydrate to deionized water is 1:0.8-1:1.5.

[0017] Furthermore, the drying temperature is 80-90° C. and the linear temperature increase is 2-5° C.

[0018] The tin-zinc oxide composite material sensor is prepared according to the above method.

[0019] The beneficial effects of the present invention are:

[0020] The gas sensor provided by the present invention has high accuracy and is easy to operate. The nano gas-sensitive material with high moisture resistance helps to solve the problem that the metal oxide semiconductor gas sensor in transformer oil has low sensitivity and is easily affected by water molecules in the air. DETAILED DESCRIPTION

[0021] Example 1

[0022] a. Zinc oxide and deionized water were mixed in a mass ratio of 1:3, sodium hydroxide was added to the deionized water in a mass ratio of 1:2 with zinc oxide, magnetic stirring was performed at 500 rpm for 30 min, and ultrasonic treatment was performed for 30 min.

[0023] b. The above solution was poured into an autoclave and heated at 200°C for 15h. The temperature increased linearly at 2°C during the heating process.

[0024] c. After cooling, the mixture was transferred to a centrifuge tube, washed by centrifugation with deionized water and anhydrous ethanol, and dried at a temperature of 80° C. to obtain the zinc oxide nanoparticles.

[0025] d. Mix tin tetrachloride pentahydrate and deionized water in a mass ratio of 1:0.8, add sodium hydroxide, pH is 10-11, and stir magnetically at 500 rpm for 30 minutes.

[0026] e. The obtained precipitate was co-dissolved with zinc oxide nanoparticles in deionized water and stirred to form a solution, which was heated in an autoclave at 200°C for 12 h, with the temperature increasing linearly at 2°C during the heating process.

[0027] f. After cooling, the precipitate was centrifuged and washed repeatedly with deionized water and anhydrous ethanol by centrifugation, and the precipitate was dried at a temperature of 80° C. to obtain a tin-zinc oxide composite material.

[0028] g. Place the ceramic insulating layer of the electrode layer in a beaker containing an appropriate amount of trichloroethylene solution, then place the beaker in an ultrasonic oscillator, keep oscillating for 30 minutes, then wash it twice with anhydrous ethanol and deionized water alternately, and then dry it in the shade.

[0029] h. Take an appropriate amount of nanopowder as a gas-sensitive material and put it into agate for grinding. After sufficient grinding, add an appropriate amount of deionized water and anhydrous ethanol to prepare a uniformly mixed paste.

[0030] i. Use a coating pen to evenly apply the prepared gas-sensitive material slurry on the ceramic insulating layer where the signal electrode layer is provided, so that at least a portion of the signal electrode layer and the ceramic insulating layer are coated with the gas-sensitive material layer. After the gas-sensitive material slurry is applied, place the sensor in an oven for low-temperature drying to complete the production of the planar gas sensor.

[0031] When used to detect dissolved CO gas in oil, it has high moisture resistance and high sensitivity, and the detection limit can reach 1.45ppm.

[0032] Example 2

[0033] a. Zinc oxide and deionized water were mixed in a mass ratio of 1:3.5, sodium hydroxide was added to the deionized water in a mass ratio of 1:3 with zinc oxide, magnetic stirring was performed at 500 rpm for 30 min, and ultrasonic treatment was performed for 30 min.

[0034] b. The above solution was poured into an autoclave and heated at 200°C for 15h. The temperature increased linearly at 3°C ​​during the heating process.

[0035] c. After cooling, the mixture was transferred to a centrifuge tube, washed by centrifugation with deionized water and anhydrous ethanol, and dried at a temperature of 85° C. to obtain the zinc oxide nanoparticles.

[0036] d. Mix tin tetrachloride pentahydrate and deionized water in a mass ratio of 1:1, add sodium hydroxide, pH is 10-11, and stir magnetically at 500 rpm for 30 minutes.

[0037] e. The obtained precipitate was co-dissolved with zinc oxide nanoparticles in deionized water and stirred to form a solution, which was heated in an autoclave at 200°C for 12 h, with the temperature increasing linearly at 3°C ​​during the heating process.

[0038] f. After cooling, the precipitate was centrifuged and washed repeatedly with deionized water and anhydrous ethanol by centrifugation, and the precipitate was dried at a temperature of 85° C. to obtain a tin-zinc oxide composite material.

[0039] g. Place the ceramic insulating layer of the electrode layer in a beaker containing an appropriate amount of trichloroethylene solution, then place the beaker in an ultrasonic oscillator, keep oscillating for 30 minutes, then wash it twice with anhydrous ethanol and deionized water alternately, and then dry it in the shade.

[0040] h. Take an appropriate amount of nanopowder as a gas-sensitive material and put it into agate for grinding. After sufficient grinding, add an appropriate amount of deionized water and anhydrous ethanol to prepare a uniformly mixed paste.

[0041] i. Use a coating pen to evenly apply the prepared gas-sensitive material slurry on the ceramic insulating layer where the signal electrode layer is provided, so that at least a portion of the signal electrode layer and the ceramic insulating layer are coated with the gas-sensitive material layer. After the gas-sensitive material slurry is applied, place the sensor in an oven for low-temperature drying to complete the production of the planar gas sensor.

[0042] When used to detect dissolved CO gas in oil, it has high moisture resistance and high sensitivity, and the detection limit can reach 0.92ppm.

[0043] Example 3

[0044] a. Zinc oxide and deionized water were mixed in a mass ratio of 1:4, sodium hydroxide was added to the deionized water in a mass ratio of 1:5 with zinc oxide, magnetic stirring was performed at 500 rpm for 30 min, and ultrasonic treatment was performed for 30 min.

[0045] b. The above solution was poured into an autoclave and heated at 200°C for 15h. The temperature increased linearly at a rate of 5°C during the heating process.

[0046] c. After cooling, the mixture was transferred to a centrifuge tube, washed with deionized water and anhydrous ethanol by centrifugation, and dried at 90° C. to obtain the zinc oxide nanoparticles.

[0047] d. Mix tin tetrachloride pentahydrate and deionized water in a mass ratio of 1:1.5, add sodium hydroxide, pH is 10-11, and stir magnetically at 500 rpm for 30 minutes.

[0048] e. The obtained precipitate was co-dissolved with zinc oxide nanoparticles in deionized water and stirred to form a solution, which was heated in an autoclave at 200°C for 12 h, with the temperature increasing linearly at 5°C during the heating process.

[0049] f. After cooling, the precipitate was centrifuged and washed repeatedly with deionized water and anhydrous ethanol by centrifugation, and the precipitate was dried at a temperature of 90° C. to obtain a tin-zinc oxide composite material.

[0050] g. Place the ceramic insulating layer of the electrode layer in a beaker containing an appropriate amount of trichloroethylene solution, then place the beaker in an ultrasonic oscillator, keep oscillating for 30 minutes, then wash it twice with anhydrous ethanol and deionized water alternately, and then dry it in the shade.

[0051] h. Take an appropriate amount of nanopowder as a gas-sensitive material and put it into agate for grinding. After sufficient grinding, add an appropriate amount of deionized water and anhydrous ethanol to prepare a uniformly mixed paste.

[0052] i. Use a coating pen to evenly apply the prepared gas-sensitive material slurry on the ceramic insulating layer where the signal electrode layer is provided, so that at least a portion of the signal electrode layer and the ceramic insulating layer are coated with the gas-sensitive material layer. After the gas-sensitive material slurry is applied, place the sensor in an oven for low-temperature drying to complete the production of the planar gas sensor.

[0053] When used to detect dissolved CO gas in oil, it has high moisture resistance and high sensitivity, and the detection limit can reach 1.18ppm.

[0054] The above describes the embodiments of the present invention in detail. However, the present invention is not limited to the above embodiments. Various modifications are possible within the scope of knowledge possessed by a person skilled in the art without departing from the spirit of the present invention. Furthermore, although certain specific terms are used in this specification, these terms are used for convenience only and do not constitute any limitation of the present invention.

Claims

1. A method for preparing a tin-zinc oxide composite material sensor, characterized in that The tin-zinc oxide composite material sensor was prepared according to the following method: a. Zinc oxide and deionized water were mixed in a certain proportion, sodium hydroxide was added to deionized water in a certain proportion with zinc oxide, magnetic stirring was performed at 500 rpm for 30 min, and ultrasonic treatment was performed for 30 min to obtain a solution; b. The above solution was poured into an autoclave and heated at 200 ° C for 15h. The temperature increased linearly at a certain temperature during the heating process; c. After cooling, the mixture was transferred to a centrifuge tube, washed with deionized water and anhydrous ethanol, and dried at a certain temperature to obtain the zinc oxide nanoparticles; d. Tin tetrachloride pentahydrate was mixed with deionized water in a certain proportion, sodium hydroxide was added, the pH was 10-11, and magnetic stirring was performed at 500 rpm for 30 min; e. The obtained precipitate was dissolved in deionized water and stirred with zinc oxide nanoparticles to form a solution, which was heated in an autoclave at 200 ° C for 12 h, with the temperature increasing linearly at a certain temperature during the heating process; f. After cooling, the precipitate was centrifuged and washed repeatedly with deionized water and anhydrous ethanol by centrifugation, and the precipitate was dried at a certain temperature to obtain a tin-zinc oxide composite material; g. The ceramic insulating layer of the electrode layer is placed in a beaker containing an appropriate amount of trichloroethylene solution, and then the beaker is placed in an ultrasonic oscillator and kept oscillating for 30 minutes. After that, it is washed twice with anhydrous ethanol and deionized water, respectively, and then dried in the shade; h. Take an appropriate amount of nanopowder as a gas-sensitive material and grind it into agate. After grinding thoroughly, add an appropriate amount of deionized water and anhydrous ethanol to form a uniformly mixed paste. i. Use a coating pen to evenly apply the prepared gas-sensitive material slurry on the ceramic insulating layer where the signal electrode layer is provided, so that at least a portion of the signal electrode layer and the ceramic insulating layer are coated with the gas-sensitive material layer. After the gas-sensitive material slurry is applied, place the sensor in an oven for low-temperature drying to complete the production of the planar gas sensor.

2. The method for preparing the tin-zinc oxide composite material sensor according to claim 1, characterized in that The mass ratio of zinc oxide to deionized water is 1:3-1:4, and the mass ratio of zinc oxide to sodium hydroxide is 1:2-1:

5.

3. The method for preparing the tin-zinc oxide composite material sensor according to claim 1, characterized in that The mass ratio of tin tetrachloride pentahydrate to deionized water is 1:0.8-1:1.

5.

4. The method for preparing the tin-zinc oxide composite material sensor according to claim 1, characterized in that The drying temperature is 80-90℃, and the linear temperature increase is 2-5℃.

5. Tin-zinc oxide composite material sensor, characterized in that The tin-zinc oxide composite material sensor is prepared according to the method of any one of claims 1 to 4.