Preparation method and application of confinement sensitization type sensor

Abstract

The invention discloses a confinement sensitization sensor based on a carbon nanotube template, a controllable preparation method of the confinement sensitization sensor as an acetone MEMS gas sensor and application of the confinement sensitization sensor as the acetone MEMS gas sensor, the controllable preparation of the confinement sensitization sensor is realized through an atomic layer deposition technology based on the carbon nanotube template, and the sensitivity of the sensor is improved through the concentration enrichment effect caused by confinement. The high-sensitivity and specific detection of the material on acetone is improved. The preparation method is simple, the response recovery time of gas response sensitivity and selectivity is reduced through a confinement sensitization method, the stability of a gas sensor in a long-term working state can be improved when the gas sensor is manufactured into an MEMS device, and the application prospect is wider.

Description

Technical Field

[0001] The present invention relates to the technical field of sensor preparation, and in particular, to a preparation method and application of a confinement-sensitized sensor. Background Art

[0002] As a device capable of sensing and measuring information such as physical quantities and chemical quantities, sensors have been widely used in modern technology. However, in many practical application scenarios, such as the detection of trace harmful substances in the environment and the detection of low-concentration markers in organisms, extremely high requirements are imposed on the sensitivity of sensors. Traditional sensors often face problems such as weak signals and poor accuracy when detecting low-concentration targets.

[0003] To improve the sensitivity of sensors, the method of confinement sensitization has emerged. Some existing methods for preparing confinement-sensitized sensors have defects such as poor process stability, complex preparation processes, high costs, or unsatisfactory sensitization effects, which limit the large-scale application and development of such high-performance sensors. Therefore, there is an urgent need for an efficient, stable preparation method that can significantly improve the sensitivity of sensors. Summary of the Invention

[0004] The present invention provides a preparation method of a confinement-sensitized sensor. One of its purposes is to provide a confinement-sensitized gas sensor product. Another purpose of the present invention is to provide an application of the above product.

[0005] The present invention is achieved through the following technical solutions:

[0006] A preparation method of a confinement-sensitized sensor, by depositing different metal oxide precursors on the surface of carbon nanotubes with different morphologies through atomic layer deposition, and then sintering to obtain a confinement-sensitized sensor, specifically including the following steps:

[0007] Step 1: Put carbon nanotube helices into an atomic layer deposition (ALD) reactor, add a Zn source to the raw material bottle, and deposit ZnO precursors for 500 cycles at 300°C.

[0008] Step 2: Heat the ZnO precursors containing carbon nanotubes in a muffle furnace at 550°C to remove the carbon nanotubes and obtain a ZnO confinement-sensitized sensor.

[0009] Further, in the above step 1, the metal oxide is at least one of ZnO, In2O3, TiO2, and Al2O3

[0010] Further, in the above step 1, an In source, an Al source, or a Ti source is used instead of the Zn source.

[0011] Further, in the above step 1, carbon nanotube straight tubes are used instead of carbon nanotube helices.

[0012] Further, in the first step, the ALD deposition temperature is 100 - 400 °C.

[0013] Further, in the first step, the number of ALD deposition cycles is set to 10 - 2000 cycles.

[0014] Further, in the second step, the temperature of the muffle furnace is set to 450 °C and 650 °C.

[0015] A preparation method of a confined - sensitized sensor and its application in acetone gas detection.

[0016] The present invention provides a method for controllably preparing a confined - sensitized sensor. The principle is that carbon nanotube helices are used as sacrificial templates, and a Zn source is introduced in ALD to realize the preparation of a ZnO confined - sensitized sensor. The preparation method of the present invention is simple. By preparing ZnO helices through confinement, the sensitivity and selectivity to gases are enhanced. When making it into a MEMS device, the energy consumption of the gas sensor can be reduced.

[0017] The present invention has the following beneficial effects: A preparation method of a confined - sensitized sensor of the present invention realizes the controllable preparation of a confined - sensitized sensor by precisely regulating the deposition of metal oxide precursors on a carbon nanotube template. The effects are specifically shown in the following aspects:

[0018] (1) The present invention realizes the preparation of a confined - sensitized ZnO sensor;

[0019] (2) The present invention realizes the dual - function detection of a ZnO sensor for nitric oxide and hydrogen fluoride;

[0020] (3) The present invention realizes the improvement of the sensitivity of a ZnO sensor to nitric oxide and hydrogen fluoride. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the preparation of an embodiment of the present invention.

[0022] Figure 2 It is a TEM schematic diagram of the ZnO helices prepared in an embodiment of the present invention.

[0023] Figure 3 It is a schematic diagram of the ZnO straight tubes prepared in an embodiment of the present invention.

[0024] Figure 4 It is a schematic diagram of the response - recovery curve of the gas sensor of the present invention to 5 ppm acetone at a working temperature of 260 °C. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] The following is a detailed description of the embodiments of the present invention in conjunction with the accompanying drawings: These embodiments are implemented on the premise of the technical solution of the present invention, and detailed implementation manners and specific operation processes are given. However, the protection scope of the present invention is not limited to the following embodiments.

[0026] As Figures 1-4 shown,

[0027] Embodiment 1: A preparation method of a ZnO confined and sensitized sensor based on a carbon nanotube template as an acetone MEMS gas sensor. By atomic layer deposition technology, a ZnO precursor is deposited on a carbon nanotube, and then sintered to prepare a ZnO nanotube composite material. Combining it with a MEMS device to prepare a MEMS gas sensor for acetone detection, including the following steps:

[0028] Step 1: Put the carbon nanotubes into an atomic layer deposition (ALD) reactor, add a Zn source to the raw material bottle, and deposit different cycles of ZnO precursor (500 cycles) at 300 °C.

[0029] Step 2: Heat the In2O3 precursor containing carbon nanotubes in a muffle furnace at 550 °C to remove the carbon nanotubes and obtain a ZnO confined and sensitized sensor.

[0030] Embodiment 2: A preparation method of an In2O3 confined and sensitized sensor based on a carbon nanotube template as an acetone MEMS gas sensor, which is similar to the steps of Embodiment 1, including the following steps:

[0031] Step 1: Put the carbon nanotubes into an atomic layer deposition (ALD) reactor, add an In source to the raw material bottle, and deposit different cycles of In2O3 precursor (500 cycles) at 300 °C.

[0032] Step 2: Heat the In2O3 precursor containing carbon nanotubes in a muffle furnace at 550 °C to remove the carbon nanotubes and obtain an In2O3 confined and sensitized sensor.

[0033] Embodiment 3: A preparation method of a TiO2 confined and sensitized sensor based on a carbon nanotube template as an acetone MEMS gas sensor, which is similar to the steps of Embodiment 1, and is prepared according to the following steps:

[0034] Step 1: Put the carbon nanotubes into an atomic layer deposition (ALD) reactor, add a Ti source to the raw material bottle, and deposit different cycles of TiO2 precursor (500 cycles) at 300 °C.

[0035] Step 2: Heat the TiO2 precursor containing carbon nanotubes in a muffle furnace at 550 °C to remove the carbon nanotubes and obtain a TiO2 confined and sensitized sensor.

[0036] Example 4: A preparation method of an Al2O3 confinement-sensitized sensor based on a carbon nanotube template as an acetone MEMS gas sensor is similar to the steps in Example 1 and is prepared according to the following steps:

[0037] Step 1: The carbon nanohelix tube is placed in an atomic layer deposition (ALD) reactor, and an Al source is added to the raw material bottle, and the Al2O3 precursor is deposited at 300 °C for different cycles (500 cycles).

[0038] Step 2: The Al2O3 precursor containing carbon tubes is placed in a muffle furnace and heated at 550 °C to remove the carbon tubes, obtaining an Al2O3 confinement-sensitized sensor.

[0039] As Figure 4 shown, the response-recovery curve of the gas sensor of the device obtained in the above Example 1 to 10 ppm hydrogen fluoride at the working temperature of 270 °C shows that the gas sensor has excellent response characteristics.

[0040] The above has described the embodiments of the present invention in conjunction with the drawings, but the present invention is not limited to the above embodiments, and various changes can also be made according to the purpose of the invention of the present invention. Any changes, modifications, substitutions, combinations or simplifications made based on the spirit and principle of the technical solution of the present invention shall be equivalent replacement methods. As long as they meet the invention purpose of the present invention and do not deviate from the technical principle and inventive concept of the present invention, they all belong to the protection scope of the present invention.

Claims

1. A method for preparing a confined-domain enhanced-sensitivity sensor, characterized in that: Different metal oxide precursors are deposited on the surface of carbon nanotubes of different shapes by atomic layer deposition, and then sintered to obtain a confined area enhanced sensitivity sensor, which specifically includes the following steps: Step 1: Place the carbon nanotube in an atomic layer deposition (ALD) reactor, add a Zn source to the raw material bottle, and deposit 500 cycles of ZnO precursor at 300 °C; Step 2: Heat the ZnO precursor containing carbon tubes at 550°C in a muffle furnace to remove the carbon tubes to obtain a ZnO confinement sensitivity enhancement sensor.

2. The method for preparing a confined-domain enhanced-sensitivity sensor according to claim 1, characterized in that: In the step 1, the metal oxide is at least one of ZnO, In2O3, TiO2, and Al2O3.

3. The method for preparing a confined-domain enhanced-sensitivity sensor according to claim 1, characterized in that: In the step 1, an In source, an Al source or a Ti source is used instead of a Zn source.

4. The method for preparing a confined-domain enhanced-sensitivity sensor according to claim 1, characterized in that: In the step 1, carbon nanotubes are used instead of carbon nanotubes.

5. The method for preparing a confined-domain enhanced-sensitivity sensor according to claim 1, characterized in that: In the step 1, the ALD deposition temperature is 100-400°C.

6. The method for preparing a confined-domain enhanced-sensitivity sensor according to claim 1, characterized in that: In the step 1, the number of ALD deposition cycles is set to 10-2000 cycles.

7. The method for preparing a confined-domain enhanced-sensitivity sensor according to claim 1, characterized in that: In the step 2, the temperature of the muffle furnace is set to 450°C and 650°C.

8. A method for preparing the confined-domain enhanced-sensitivity sensor as claimed in claim 1, and its application in acetone gas detection.

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