KR20220156195A - Led-based gas sensor with locally integrated two-dimensional transition metal chalcogenide and method of preparing the same - Google Patents

Abstract

The present application relates to an LED-based gas sensor in which a two-dimensional transition metal chalcogenide is locally integrated and a manufacturing method thereof, capable of detecting and monitoring NO_2 based on high sensitivity and complete recovery performance at room temperature. The LED-based gas sensor in which a two-dimensional transition metal chalcogenide is locally integrated includes a light source unit, a gas detection unit, and a plurality of sensor electrode units.

Description

LED-BASED GAS SENSOR WITH LOCALLY INTEGRATED TWO-DIMENSIONAL TRANSITION METAL CHALCOGENIDE AND METHOD OF PREPARING THE SAME}

The present application relates to an LED-based gas sensor in which two-dimensional transition metal chalcogenides are locally integrated and a method for manufacturing the same, which is a two-dimensional transition metal chalcogen capable of detecting and monitoring NO ₂ based on high sensitivity and complete recovery performance at room temperature. An LED-based gas sensor with locally integrated cargo and a manufacturing method thereof.

The performance of gas sensors can be evaluated based on sensitivity, recovery performance, durability, etc., and many studies are still being conducted to improve them.

Transition metal dichalcogenides (TMDCs) are nanomaterials that are widely used as gas-sensing materials with a finite band gap and a high surface area to volume ratio. Among them, Molybdenum Disulfide (MoS2) shows promising properties as a NO ₂ sensing material based on its excellent molecular adsorption coefficient and high selectivity for Nitrogen Dioxides (NO ₂ ). However, when NO ₂ is sensed at room temperature, MoS ₂ has the disadvantage of low sensitivity and incomplete recovery performance, and many studies have been conducted to solve this problem. In one study, the recovery performance of the sensor was improved by facilitating the desorption of gas molecules adsorbed on the surface of MoS ₂ by applying thermal energy. However, since the supply of excessive heat energy may cause concerns about excessive power consumption or safety, a new method to replace the supply of heat energy has been required.

Light irradiation creates an electron-hole pair in MoS ₂ to supply additional electrons to be combined with NO ₂ adsorbed, and at the same time to supply holes that can facilitate the desorption of NO ₂ by combining with the electrons combined with NO ₂ in the recovery stage It is a good way to improve the sensitivity and recovery performance of the sensor, and it is a good substitute for thermal energy. Based on this fact, many researchers have improved the performance of gas sensors by using UV light or visible light. However, in previous studies, a separate light source was required to irradiate light, which may limit the portability of the gas sensor. In addition, since light loss may occur in proportion to the distance between the sensor and the light source, a method for efficiently irradiating light is required. In addition, since UV light or visible light (High Energy Visible light) having a wavelength of 500 nm or less has strong energy, it may damage human eyes or sensing materials.

While solving these problems, it is time to research on a gas sensor that is easy to manufacture and easy to carry.

According to an embodiment of the present application, the sensitivity and recovery performance of MoS ₂ is improved by using Low Energy Visible light that is harmless to the human body without damaging MoS ₂ , and MoS ₂ locally integrated into the light source is It is intended to provide a gas sensor capable of improving efficient gas detection performance by directly absorbing emitted light.

One aspect of the present application relates to a gas sensor.

As an example, the gas sensor includes a light source unit for irradiating light of a predetermined wavelength; a gas detection unit formed in one region of the light source unit and including a transition metal chalcogen compound capable of adsorbing a predetermined gas by absorbing light of the above wavelength; and a plurality of sensor electrode units formed in one region of the gas sensing unit.

As an example, the light source may be a light-emitting diode (LED).

As an example, the range of wavelengths may be 625 nm to 639 nm and 680 nm to 694 nm.

As an example, the transition metal chalcogen compound may include molybdenum disulfide (MoS ₂ ).

As an example, the sensor electrode unit may include silver (Ag).

As an example, peaks may be observed at 383 cm ⁻¹ and 410 cm ⁻¹ respectively when measuring a Raman spectrum of the gas detector.

As an example, when the gas sensor is exposed to 10 ppm of NO 2 under the power of a light source of 400 mW, a reactivity value defined by the following relational expression may be up to 160%.

[relational expression]

Reactivity (%) = (Ig-Ia)/Ia * 100

(Here, Ig is the current of the sensor after exposure to NO ₂ , and Ia is the initial current of the sensor before exposure to NO ₂ )

As an example, the gas sensor may detect at least one gas selected from VOC (acetone, ethanol, p-xylene, toluene, benzene, and ethyl benzene), NO ₂ , CO, and NH ₃ .

Another aspect of the present application relates to a method of manufacturing a gas sensor.

As an example, a method of manufacturing a gas sensor may include preparing a light source unit for irradiating light of a predetermined wavelength; forming a gas sensing unit including a transition metal chalcogenide capable of adsorbing a predetermined gas by absorbing light of the wavelength in one region of the light source unit; and forming a plurality of sensor electrode units formed in one region of the gas sensing unit.

As an example, the forming of the gas sensing unit may include compressing a transition metal chalcogen compound in powder form to form a pellet; and forming a coating portion by drawing on one area of the light source using the formed pellets.

As an example, in the step of forming the gas sensing unit, the powdery transition metal chalcogen compound may have a compressive strength of 0.3 to 0.7 GPa.

As an example, forming the sensor electrode unit may include attaching silver paste to one region of the gas sensing unit.

Another aspect of the present application relates to a gas sensor kit.

As an example, the gas sensor kit includes the aforementioned gas sensor; a controller connected to the gas sensor and receiving a result detected by the gas detection sensor; a communication module for transmitting a gas detection result detected by the gas sensor to a controller; a battery connected to the gas sensor, the light source and the communication module to supply power; and a gas inlet and pump for injecting a gas to be sensed into the gas sensor. can include

As an example, the gas sensor may be provided in the form of a cartridge to be detachable from the gas detection kit.

As an example, the gas sensor kit is connected to a smart device through a communication module, and the gas concentration detection result detected through the gas sensor is transmitted to the smart device in real time, or the gas concentration detected is monitored in real time and the monitored result is stored. It may be arranged to make this possible.

According to an embodiment of the present application, an LED-based gas sensor locally integrated with a two-dimensional transition metal chalcogenide capable of detecting and monitoring NO ₂ based on high sensitivity and complete recovery performance at room temperature can be provided.

According to an embodiment of the present application, as well as MoS ₂ , two-dimensional transition metal chalcogenides that can be combined with various nanomaterials capable of absorbing specific wavelengths and adsorbing gases and various LEDs and light sources emitting specific wavelengths are locally can provide an integrated LED-based gas sensor.

According to an embodiment of the present application, it is possible to implement a high-performance gas sensor by integrating a two-dimensional nanomaterial into a light source such as an LED that is already used in daily life and industrial settings.

1 is a schematic diagram of a gas sensor according to an embodiment of the present application.
2 is a schematic diagram for explaining a manufacturing method of a gas sensor according to an embodiment of the present application.
3 is a flow chart for explaining a method of manufacturing a gas sensor according to an embodiment of the present application.
4 is a scanning electron microscope (SEM) image of molybdenum disulfide formed in the LED light source unit.
5 is a schematic diagram of a gas detection kit according to an embodiment of the present application.
6 is a graph of Raman spectra measurement results of the LED surface and the LED surface coated with molybdenum disulfide.
7 is a graph of the result of measuring the electroluminescence peak of a 100 mW power LED and the absorbance spectra of MoS ₂ .
8 is a graph of the results of measuring the characteristics of LED power consumption and the amount of current change according to LED power consumption when exposed to NO ₂ .
9 is a graph showing the results of measuring responsiveness and recovery performance according to power consumption.
10 is a graph showing the result of measuring the reactivity to NO ₂ according to the concentration of NO ₂ .
11 is a graph showing the results of measuring reactivity to NH ₃ .
12 is a graph of results obtained by measuring the change in current of the sensor for Electroluminescence peak and NO ₂ of White LED according to power change.

Terms used in this application are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, terms such as "include" or "have" are intended to designate that the features, components, etc. described in the specification exist, but one or more other features or components may not exist or be added. That doesn't mean there aren't any.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in this application, it should not be interpreted in an ideal or excessively formal meaning. don't

In the present application, the term "nano" may refer to a size in a nanometer (nm) unit, for example, from 1 to 1,000 nm, but is not limited thereto. In addition, the term "nanoparticle" in this specification may mean a particle having an average particle diameter in nanometer (nm) units, for example, may mean a particle having an average particle diameter of 1 to 1,000 nm, but It is not limited.

Hereinafter, a gas sensor and a manufacturing method thereof of the present application will be described in detail with reference to the accompanying drawings. However, the accompanying drawings are illustrative, and the scope of the gas sensor and manufacturing method thereof of the present application is not limited by the accompanying drawings.

gas sensor

One aspect of the present application relates to a gas sensor. Visible light, which is harmless to the human body, is used without damaging molybdenum disulfide, which serves as a gas sensing unit, to improve the sensitivity and recovery performance of the sensor. A sensor capable of improving efficient gas detection performance is presented. In addition, since the gas sensing function can be provided anywhere as long as there is a light source, there is no restriction on the portability of the gas sensor.

1 is a schematic diagram of a gas sensor according to an embodiment of the present application. As shown in FIG. 1, the gas sensor 1 includes a light source unit 11 for irradiating light of a predetermined wavelength; a gas detection unit 13 formed in one region of the light source unit and including a transition metal chalcogen compound capable of adsorbing a predetermined gas by absorbing light of the above wavelength; and a plurality of sensor electrode units 15 formed in one region of the gas sensing unit. Additionally, a light source electrode unit (not shown) may be included.

The light source unit may emit light of a predetermined wavelength. For example, the light source unit may be a light-emitting diode (LED). However, it is not limited thereto.

The range of wavelengths may be 625 nm to 639 nm and 680 nm to 694 nm.

MoS ₂ may have high absorbance at 625 nm to 639 nm, which is a wavelength corresponding to light absorption due to B exciton transition. In addition, absorbance may be high even at 694 nm within 680 nm, which is a wavelength corresponding to light absorption due to A exciton transition.

In addition, the gas detection unit is formed in one area of the light source unit. In addition, it may include a transition metal chalcogen compound capable of adsorbing a predetermined gas by absorbing light of the above wavelength.

Transition metal chalcogenide (TMC) refers to a material composed of a transition metal and a chalcogen (hydrogen group) element as indicated in the periodic table. Dichalcogenides, (Di = 2), these substances can have a two-dimensional structure (nano-layer structure). TMDC has various MX ₂ types of materials such as MoS ₂ , WS ₂ , TiS ₂ , TaS ₂ , MoSe ₂ , WSe ₂ , TiSe ₂ , TaSe ₂ , etc. Depending on the type of transition metal, it shows the properties of a conductor, semiconductor, or insulator. .

The transition metal chalcogen compound in the present application may preferably include molybdenum disulfide (MoS ₂ ).

Peaks may be observed at 383 cm ^-1 and 410 cm ^-1 respectively when measuring a Raman spectrum for the gas sensing unit. This means that a molybdenum disulfide coating layer is formed.

A plurality of sensor electrode units are formed in one region of the gas sensing unit. The sensor electrode unit may include silver (Ag). As will be described later, the silver electrode part may be formed using silver paste.

When the gas sensor is exposed to 10 ppm of NO ₂ under the power of a light source of 400 mW, a reactivity value defined by the following relational expression may be up to 160%.

[relational expression]

Reactivity (%) = (Ig-Ia)/Ia * 100

(Here, Ig is the current of the sensor after exposure to NO ₂ , and Ia is the initial current of the sensor before exposure to NO ₂ )

For example, in order to incorporate molybdenum disulfide into the LED surface, molybdenum disulfide pellets with a diameter of 10 mm, which are made by compressing molybdenum disulfide powder at a pressure of 300 MPa, are applied to the light emitting area on the LED chip that emits light in the wavelength range of 615 to 625 nm. rub After that, silver paste is applied to the surface of molybdenum disulfide to make sensor electrodes, and copper tape is used to make LED activation electrodes. After putting the fabricated sensor in the gas chamber and applying power to the electrode for activating the LED, the current change _of molybdenum disulfide was measured through the sensor electrode. It showed responsiveness and complete recovery performance. The reactivity is defined as (Ig-Ia)×100/Ia (%), where Ig is the current of the sensor after exposure to NO ₂ , and Ia is the initial current of the sensor before exposure to NO ₂ . In addition, as a result of checking the reactivity change of the sensor while raising and lowering the concentration of NO ₂ in the order of 0.1, 0.3, 0.5, 0.7, and 1 ppm, the sensitivity of the sensor was calculated as ~26%/ppm. Additionally, for 10 ppm of NH ₃ , the LED showed a reactivity of ~15% when the LED was activated, and since NH ₃ has Donor's characteristics, the sensor current decreased when exposed to the gas. Through this application, white LEDs, which are commonly used for lighting in everyday life, are given a gas detection function, enabling indoor and outdoor lighting as well as sensitive and reversible room temperature gas detection and monitoring. It showed a reactivity of ∼100% for ppm of NO ₂ .

The gas sensor may detect at least one gas selected from VOC (acetone, ethanol, p-xylene, toluene, benzene, and ethyl benzene), NO ₂ , CO, and NH ₃ within a specific concentration range.

Manufacturing method of gas sensor

Another aspect of the present application relates to a method of manufacturing a gas sensor.

2 is a schematic diagram for explaining a manufacturing method of a gas sensor according to an embodiment of the present application. Figure 2 is a state of manufacturing LED electrodes with sensor electrodes made through silver paste and copper tape after integrating (coating) molybdenum disulfide by rubbing molybdenum disulfide pellets on LEDs. To improve the gas detection performance, the LED is activated and the current change of the sensor exposed to NO ₂ can be measured through the sensor electrode.

3 is a flow chart for explaining a method of manufacturing a gas sensor according to an embodiment of the present application.

As shown in FIG. 3, the manufacturing method of the gas sensor includes preparing a light source unit for irradiating light of a predetermined wavelength (S10); Forming a gas sensing unit including a transition metal chalcogen compound capable of adsorbing a predetermined gas by absorbing light of the above wavelength in one region of the light source unit (S20); and forming a plurality of sensor electrode units formed in one region of the gas sensing unit (S30).

Hereinafter, a method of manufacturing a gas sensor will be described step by step.

First, a light source unit for irradiating light of a predetermined wavelength is prepared (S10).

The light source unit may emit light of a predetermined wavelength. For example, the light source unit may be a light-emitting diode (LED). However, it is not limited thereto.

Then, a gas sensing unit including a transition metal chalcogen compound capable of adsorbing a predetermined gas by absorbing light of the above wavelength is formed in one region of the light source unit (S20).

Forming the gas sensing unit may include forming a pellet form by compressing a transition metal chalcogenide compound in powder form; and forming a coating portion by drawing on one area of the light source using the formed pellets; can include In addition, the transition metal chalcogenide in powder form may have a compressive strength of 0.3 to 0.7 GPa.

At this time, about 200 mg of the transition metal chalcogen compound powder is put into a pellet die of a press machine and compressed at about 0.3 Gpa to prepare a pellet. Here, the compressive strength of the pellets formed using the press machine may be approximately within the range of 0.3 to 0.7 GPa. This is because, for example, when the compressive strength of the pellet is 0.3 Gpa or less, the transition metal chalcogenide compound powder cannot be properly aggregated into a pellet shape. In addition, when the compressive strength of the pellet is 0.7 Gpa or more, the pellet formed of the transition metal chalcogenide powder has a high degree of adhesion between the powders forming the pellet, so that the drawing for forming a thin film using the pellet on the substrate is not smooth. . Therefore, the compressive strength of the pellets is preferably in the range of 0.3 to 0.7 GPa.

In the coating layer formed on the light source unit, molybdenum disulfide is separated from the pellets by friction with the surface of the light source unit and attached to the light source unit by van der Waals force. For reference, the van der Waals force refers to a weak attraction between electrically neutral molecules that acts only at extremely short distances, and is a type of electric force. The van der Waals force is inversely proportional to the 6th power of the distance, so it is characterized by rapidly weakening as the distance between molecules increases.

When viewed from the side, the thickness of the gas sensing unit has a thickness of about 1 to 2 μm and may be formed in a multilayer structure. A thickness of 2 μm or more, in other words, a thickness of 5 μm or more is also possible. However, as the thickness of the gas sensing unit formed in the light source unit increases, crack generation due to mechanical deformation increases. Therefore, when the thickness of the gas sensing unit formed in the light source unit is 1 to 2 μm, high effects are generated in terms of sensing performance and mechanical stability.

4 is a scanning electron microscope (SEM) image of molybdenum disulfide formed in the LED light source unit. As shown in FIG. 4, when the transition metal chalcogen compound is formed of molybdenum disulfide, morphological features including edge regions and several layer structures can be observed in a transmission electron emission microscope (SEM) image.

Then, a plurality of sensor electrode units formed in one region of the gas sensing unit are formed (S30).

Forming the sensor electrode unit may include attaching silver paste to one region of the gas sensing unit.

gas sensor kit

Another aspect of the present application relates to a gas sensor kit.

As an example, the gas sensor kit includes the aforementioned gas sensor; a controller connected to the gas sensor and receiving a result detected by the gas detection sensor; a communication module for transmitting a gas detection result detected by the gas sensor to a controller; a battery connected to the gas sensor, the light source and the communication module to supply power; and a gas inlet and pump for injecting a gas to be sensed into the gas sensor. can include

The gas sensor may be provided in the form of a cartridge to be detachable from the gas detection kit. The gas sensor kit is connected to a smart device through a communication module, and the gas concentration detection result detected through the gas sensor is transmitted to the smart device in real time, or the gas concentration detected is monitored in real time and the monitored result is stored. It can be.

Meanwhile, the method for manufacturing a gas detection sensor (S100) according to an embodiment of the present invention and the gas detection sensor 100 manufactured thereby can be used like a cartridge and detachable, and can be attached and detached at a desired time by a user. It can be provided as a gas detection kit 200 capable of detecting the gas concentration at a desired place in real time.

5 is a schematic diagram of a gas detection kit according to an embodiment of the present application.

Referring to FIG. 5 , a gas detection kit 200 according to an embodiment of the present application may include a gas sensor 100, a battery 110, a controller 120, a communication module 130, and a pump 140. can

The gas sensor 100 is a sensor manufactured by the method for manufacturing a gas detection sensor described above.

When the gas sensor 100 is mounted on the gas detection kit 200, it may be formed in the form of a cartridge to be detachable from the gas detection kit.

Meanwhile, the gas sensor 100 may detect at least one gas from VOC (acetone, ethanol, p-xylene, toluene, benzene, and ethyl benzene), NO ₂ , CO, and NH ₃ in a specific concentration range, but must be It is not limited.

The battery 110 is connected to an electrode (not shown) of the gas sensor 100 and supplies power so that the gas detection sensor 100 detects gas. Connected to the gas sensor, LED, and communication module, the gas sensor can supply power to detect gas at the same time as the LED and communication module are activated.

For reference, although not shown in the drawing, the battery 110 is a generally used battery, but its shape may be different.

The controller 120 is connected to the gas sensor and receives a result detected by the gas detection sensor 100 . For example, the controller 120 may be a microcomputer such as Arduino, but is not necessarily limited thereto.

The communication module 130 is a communication device for transmitting the gas detection result detected by the gas sensor to the controller. In this case, the communication module 130 may be a wireless module such as a Bluetooth module or may be wired, but is not necessarily limited thereto. In this way, the gas detection kit 200 itself may be wireless or wired depending on the wired/wireless type of the communication module 130 .

Here, in order to simplify the structure of the gas sensor kit 200 according to an embodiment of the present application and lighten the weight, it is preferable to be formed in a wireless form.

The pump 140 is a part for injecting a gas to be detected into the gas sensor 100 .

At this time, the gas inlet 102 is connected to the gas sensor 100, and the gas to be detected by the pump 140 is injected through the connected gas inlet 102.

Meanwhile, the gas kit 200 is connected to the user's smart device 300 through the communication module 130, and the gas concentration detection result detected through the gas detection sensor 100 is transmitted to the smart device 300 in real time. Alternatively, it may be provided to enable real-time monitoring of the detected gas concentration and storage of the monitored results.

That is, the user senses the gas concentration in a desired place in real time through the gas sensor kit 200, and the detected result is transmitted to the user's smart device 300, so that the user can grasp the measured gas concentration in real time. .

Therefore, the gas sensor manufacturing method and the gas detection sensor manufactured by the method according to an embodiment of the present application can be manufactured through a simple manufacturing process at low cost, so that the user can directly By easily drawing and manufacturing the sensor, you can easily detect gas leaks around you.

In addition, the gas sensor manufactured by the manufacturing method of the gas detection sensor of the present invention can be manufactured using several light sources having a wavelength that matches the wavelength of the region of high absorbance of the nanomaterial used for detection, and has excellent sensitivity. can have

Meanwhile, in the gas sensor kit 200 of the present invention, the gas sensor 100 can be easily mounted on the gas sensor kit 200, so that the gas concentration can be sensed in real time at a desired time and place by the user.

Hereinafter, the present application will be described in more detail through experimental examples.

[Experimental Example 1]

In order to confirm whether molybdenum disulfide is formed on the LED chip, the following experiment was performed.

Figure 6 shows the Raman spectrum of the LED chip surface and the resulting Raman spectrum after drawing molybdenum disulfide to form a coating portion. As shown in FIG. 6, it was confirmed that molybdenum disulfide was well incorporated on the LED through E ¹ _2g (in-plane vibration mode) and A _1g (out-plane vibration mode) of MoS2.

[Experimental Example 2]

Electroluminescence peak of the LED and MoS ₂ absorbance spectra measured through a UV-vis spectrophotometer are shown in FIG. 7 . As shown in FIG. 7, the Electroluminescence peak of the LED coincides with the B exciton transition peak of MoS ₂ , and through this, it was confirmed that MoS ₂ absorbs the light of the LED well.

[Experimental Example 3]

Characteristics according to the power consumption of the LED and the amount of current change according to the power consumption of the LED when exposed to NO ₂ are measured and shown in FIG. 8 . As shown in FIG. 8, it was confirmed that the reactivity was 100% or more for NO 2 of 10 ppm under the LED power of 400 mW or more.

[Experimental Example 4]

In addition, the responsiveness and recovery performance of the gas sensor according to the power consumption of the LED were tested. Responsiveness according to power consumption is measured and shown in FIG. 9 . In addition, FIG. 9 shows the results of the sensor stability comparison experiment when the LED was turned off and turned on at 400 mW five times.

As shown in FIG. 9, the best response was shown when power consumption of 400 mW was applied. In addition, compared to when the LED was turned off, when the LED was turned on at 400 mW, it showed ~40% reactivity and complete recovery performance for a NO ₂ concentration of 1 ppm, and it was confirmed that no performance degradation occurred.

[Experimental Example 5]

In addition, when the LED was activated with a power of 400 mW, an experiment was performed to confirm the reactivity according to the concentration of NO ₂ .

After activating the LED with a power of 400 mW, the reactivity to NO ₂ was measured by raising and lowering the concentration of NO ₂ in the order of 0.1, 0.3, 0.5, 0.7, 1, 3, 5, 7, and 10 ppm. shown in As shown in FIG. 10, it was confirmed that complete recovery performance was exhibited and a reactivity of 130% was achieved at a NO ₂ concentration of 10 ppm.

[Experimental Example 6]

In addition, an experiment of reactivity to NH3 was performed. Specifically, when the LED was turned off and turned on at 400 mW, the reactivity to 10 ppm NH ₃ was measured and shown in FIG. 11 . As shown in FIG. 11, it was confirmed that the reactivity was ~15% at 400 mW.

[Experimental Example 7]

In order to confirm the applicability of various light sources for manufacturing a gas sensor, the following experiments were performed. Specifically, the electroluminescence peak of the white LED according to the power change is measured and shown in FIG. 12 . Having a high peak at a wavelength of 625 nm means that the light generated from the White LED can be well absorbed by MoS ₂ . In addition, when the LED was turned off and when the LED was turned on at 200, 400, and 600 mW, the change in current of the sensor for 10 ppm of NO ₂ was measured and shown in FIG. 12 . As shown in FIG. 12, the largest current change was shown at a power of 600 mW. Through this, it was confirmed that the performance of the sensor can be improved through the White LED.

Although the above has been described with reference to the preferred embodiments of the present application, those skilled in the art can variously modify and change the present application within the scope not departing from the spirit and scope of the present invention described in the claims below. You will understand that you can.

1: gas sensor
11: light source
13: gas detection unit
15: sensor electrode
100: gas detection sensor
102: gas inlet
110: battery
120: controller
130: communication module
140: pump
200: gas detection kit
300: smart device

Claims (15)

a light source unit for irradiating light of a predetermined wavelength;
a gas detection unit formed in one region of the light source unit and including a transition metal chalcogen compound capable of adsorbing a predetermined gas by absorbing light of the above wavelength; and
A gas sensor comprising a plurality of sensor electrodes formed in one region of the gas sensing unit. According to claim 1,
The light source unit is a light-emitting diode (LED) gas sensor. According to claim 1,
The gas sensor having a wavelength range of 625 nm to 639 nm and 680 nm to 694 nm. According to claim 1,
Transition metal chalcogenide is a gas sensor containing molybdenum disulfide (MoS ₂ ). According to claim 1,
A gas sensor in which the sensor electrode unit includes silver (Ag). According to claim 1,
A gas sensor in which peaks are observed at 383 cm ^-1 and 410 cm ^-1 respectively when measuring a Raman spectrum for the gas sensing unit. According to claim 1,
A gas sensor having a reactivity value of up to 160%, defined by the following relational expression, when the gas sensor is exposed to 10 ppm of NO ₂ under the power of a light source of 400 mW.
[relational expression]
Reactivity (%) = (Ig-Ia)/Ia * 100
(Here, Ig is the current of the sensor after exposure to NO ₂ , and Ia is the initial current of the sensor before exposure to NO ₂ ) According to claim 1,
gas sensor,
A gas sensor that detects at least one gas among VOCs (acetone, ethanol, p-xylene, toluene, benzene and ethylbenzene), NO ₂ , CO and NH ₃ . In the manufacturing method of the gas sensor according to claim 1,
Preparing a light source unit for irradiating light of a predetermined wavelength;
forming a gas sensing unit including a transition metal chalcogenide capable of adsorbing a predetermined gas by absorbing light of the wavelength in one region of the light source unit; and
A method of manufacturing a gas sensor, comprising forming a plurality of sensor electrode units formed in one region of the gas sensing unit. According to claim 9,
Forming the gas sensing unit,
Compressing the transition metal chalcogenide in powder form to form a pellet; and
Forming a coating portion by drawing on one area of the light source using the formed pellets; Method for manufacturing a gas sensor comprising a. According to claim 10,
In the step of forming the gas sensing unit,
Method for producing a gas sensor in which the powdery transition metal chalcogenide compound has a compressive strength of 0.3 to 0.7 GPa. According to claim 9,
The forming of the sensor electrode unit includes attaching silver paste to one region of the gas sensing unit. The gas sensor of claim 1;
a controller connected to the gas sensor and receiving a result detected by the gas detection sensor;
a communication module for transmitting a gas detection result detected by the gas sensor to a controller;
a battery connected to the gas sensor, the light source and the communication module to supply power; and
a gas inlet and a pump for injecting a gas to be sensed into the gas sensor; Including, gas sensor kit. According to claim 13,
gas sensor,
A gas sensor kit provided in the form of a cartridge to be detachable from the gas detection kit. According to claim 13,
The gas sensor kit is connected to smart devices through a communication module,
A gas sensor kit provided to the smart device so that the gas concentration detection result detected through the gas sensor is transmitted in real time, or the gas concentration detected is monitored in real time and the monitored result is saved.

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