Ternary composite gas sensing chip, preparation method and application method thereof, and gas sensing material
阅读说明：本技术 三元复合气体传感芯片、制备方法及应用方法和气体传感材料 (Ternary composite gas sensing chip, preparation method and application method thereof, and gas sensing material ) 是由 邬建敏 刘雪梅 于 2021-09-30 设计创作，主要内容包括：本发明公开了一种三元复合气体传感芯片、制备方法及应用方法和气体传感材料,制备方法包含：步骤一,将等体积的氧化石墨烯溶液与金属离子溶液混合加入微量的PDDA,在震荡仪上震荡过夜,之后用去离子水离心洗涤若干次,重新分散在等量去离子水中,得到自组装悬浊材料；步骤二,用PDMS膜对ITO-PET叉指电极进行限域,对电极进行氧等离子体处理,将自组装悬浊材料滴涂在电极上,在加热板上烘干后,用氮气吹扫,接着在还原性蒸气中还原。本发明的三元复合气体传感芯片的制备方法及应用方法,实现了在液相中将两种带负电的二维材料微观层层组装进行复合,克服了两种带同种电荷的二维材料无法实现液相组装的问题以及宏观层层组装工艺繁琐,不易于产业化的问题。(The invention discloses a ternary composite gas sensing chip, a preparation method, an application method and a gas sensing material, wherein the preparation method comprises the following steps: mixing an isometric graphene oxide solution and a metal ion solution, adding a trace amount of PDDA, oscillating overnight on an oscillator, centrifugally washing for a plurality of times by using deionized water, and dispersing in the same amount of deionized water again to obtain a self-assembly suspension material; and step two, limiting the ITO-PET interdigital electrode by using a PDMS film, carrying out oxygen plasma treatment on the electrode, dripping the self-assembly suspension material on the electrode, drying on a heating plate, purging by using nitrogen, and then reducing in reducing steam. The preparation method and the application method of the ternary composite gas sensing chip provided by the invention realize the combination of two negatively charged two-dimensional materials by microscopic layer-by-layer assembly in a liquid phase, and overcome the problems that two-dimensional materials with the same charge cannot realize liquid phase assembly and the problems that the macroscopic layer-by-layer assembly process is complicated and difficult to industrialize.)
1. A preparation method of a ternary composite gas sensing chip is characterized by comprising the following steps:
step one, mixing an isometric graphene oxide solution and a molybdenum disulfide solution, uniformly oscillating, adding a trace amount of PDDA, oscillating overnight on an oscillator, centrifugally washing for a plurality of times by using deionized water, and re-dispersing in the same amount of deionized water to obtain a self-assembly suspension material;
step two, mixing an isometric graphene oxide solution with a metal ion solution, uniformly oscillating, adding a trace amount of PDDA, oscillating overnight on an oscillator, centrifugally washing for a plurality of times by using deionized water, and re-dispersing in equivalent deionized water to obtain a self-assembly suspension material;
and step three, carrying out domain limitation on the ITO-PET interdigital electrode by using a PDMS film, carrying out oxygen plasma treatment on the electrode, dripping the self-assembly suspension material prepared in the step one or the step two on the electrode, drying the electrode on a heating plate, purging the electrode by using nitrogen, then placing the electrode into reducing steam for reduction for 10-20min at the temperature of 60-100 ℃ to obtain a ternary composite gas sensing chip unit, and forming the ternary composite gas sensing chip by using one or more ternary composite gas sensing chip units.
2. The method for preparing a ternary complex gas sensor chip according to claim 1,
the metal ion solution is a chloride solution of high-valence metal ions.
3. The method for preparing a ternary complex gas sensor chip according to claim 2,
the specific method of the second step is as follows: adding a 10mM chloride solution into an isometric 0.5mg/mL graphene oxide solution, uniformly oscillating, adding a trace amount of 1% Wt. PDDA, wherein the volume ratio of the added PDDA to the chloride solution is 0.03-0.08, oscillating overnight in an oscillator, centrifugally washing for 2-5 times by using deionized water, and re-dispersing in the same amount of deionized water to obtain the self-assembly suspension material.
4. The method for preparing a ternary complex gas sensor chip according to claim 3,
the chloride solution is one of ferric chloride, cobalt chloride, nickel chloride, copper chloride, cerium chloride, chromium chloride and manganese chloride.
5. The method for preparing a ternary complex gas sensor chip according to claim 1,
the specific method of the first step comprises the following steps: adding 10mM molybdenum disulfide solution into 0.5mg/mL graphene oxide solution with the same volume, uniformly oscillating, then adding a trace of 1% Wt. PDDA, wherein the volume ratio of the added PDDA to the molybdenum disulfide solution is 0.03-0.08, oscillating overnight in an oscillator, then centrifugally washing for 2-5 times by using deionized water, and re-dispersing in the deionized water with the same volume to obtain the self-assembly suspension material.
6. The method for preparing a ternary complex gas sensor chip according to any one of claims 1 to 5,
the molecular weight range of PDDA is less than 350 kDa.
7. The method for preparing a ternary complex gas sensor chip according to claim 1,
the reducing steam is hydrazine hydrate steam.
8. A ternary composite gas sensing material, which is prepared according to the first step of the preparation method of the ternary composite gas sensing chip of any one of claims 1 to 7, and is a multilayer structure of PDDA intercalated graphene oxide and molybdenum disulfide.
9. A ternary composite gas sensing material, which is prepared according to the second step of the preparation method of the ternary composite gas sensing chip of any one of claims 1 to 7, and is a multilayer structure of PDDA intercalated graphene oxide and metal ions.
10. A ternary composite gas sensing chip prepared by the method according to any one of claims 1 to 7, comprising one or more ternary composite gas sensing chip units.
11. The ternary composite gas sensing chip according to claim 10, comprising a plurality of said ternary composite gas sensing chip units, each of said ternary composite gas sensing chip units using a different self-assembled suspension material.
12. An application method of a ternary composite gas sensing chip is characterized by comprising the following steps:
placing the ternary composite gas sensing chip prepared by the preparation method of the ternary composite gas sensing chip according to any one of claims 1 to 7 in a gas flow cell for gas testing, wherein in the testing process, carrier gas is firstly introduced until a baseline tends to be stable, then sample gas is introduced at the same flow rate, and under a given voltage, the current value of the ternary composite gas sensing chip is tested through a skin ampere meter to obtain data of the relation between the current value and time, and the sample gas is identified according to the data.
13. The method of using a ternary complex gas sensor chip according to claim 12,
the ternary composite gas sensing chip comprises a plurality of different ternary composite gas sensing chip units, each ternary composite gas sensing chip unit can obtain data of the relation between a current value and time, and the sample gas is identified according to the processing and analysis of a plurality of data.
14. The method of using a ternary complex gas sensor chip according to claim 12,
the carrier gas is background gas of the sample gas;
the sample gas is organic and/or inorganic volatile gas;
the sample gas is one or more of ammonia gas, hydrogen sulfide, nitric oxide, nitrogen dioxide and volatile organic gases such as acetone and isoprene.
15. The method of using a ternary complex gas sensor chip according to claim 12,
the carrier gas is pretreated environmental gas;
the sample gas is the gas exhaled by the human body after pretreatment;
the pretreatment mode is that the gas is soaked in a Teflon pipeline with the inner diameter of 2-10 mm, which is immersed in an ice water bath by 10-50 cm.
Technical Field
The invention belongs to the technical field of gas sensing, and particularly relates to a ternary composite gas sensing chip, a preparation method and an application method thereof, and a gas sensing material.
Background
Graphene is a two-dimensional crystalline material consisting of a monolayer of carbon, with each C atom being represented by SP2The hybrid tracks form a hexagonal honeycomb structure, and have a large specific surface area and high room-temperature carrier mobility. Due to the excellent electrochemical characteristics of graphene, the graphene can be widely applied to the field of gas sensors. However, the fact that pure graphene is a zero-bandgap semiconductor and electrons can flow freely in the graphene as metal also limits some applications of the graphene as a gas sensor to a certain extent. In recent years, researchers compound graphene with other materials or perform covalent/non-covalent modification on graphene, so as to adjust the band gap of graphene and improve the gas sensing performance of graphene. Lizhai Zhang et al graphene and SnO2Adopts hydrothermal synthesis method to compound (Octahedral SnO)2/Graphene Composites with Enhanced Gas-Sensing Performance at Room Temperature.[J].ACS applied materials&interfaces,2019.), found that the composite material is p-NO compared to pure graphene2The response value of the method is obviously improved, and the selectivity is better. However, the metal oxide based gas sensor generally has a problem that the metal oxide based gas sensor needs to work at a high temperature, and although the working temperature of the metal oxide based gas sensor can be reduced to a certain extent by adding graphene, the metal oxide based gas sensor cannot obtain good gas sensing performance at room temperature. In addition, Nicolas R.Tanguy et al complexed azagraphene PANI with (Sensors/Biosensors: Nanocomposite of Nitrogen-Doped Graphene/Polyaniline for Enhanced Ammonia Gas Detection (adv. Mater. interfaces 16/2019) [ J]Advanced Materials Interfaces,2019,6(16), the composite material is for NH3Has larger response value and obvious selectivity, but the sensitivity of the composite material is lower, gases with ppb level can not be detected because of dozens to hundreds of ppm, and a hydrothermal method commonly used for preparing the composite materialIs also poor in repeatability. In addition to compounding other materials with graphene, researchers also modify and modify graphene with several reagents. For example, Zhu et al use different ionic liquids to modify graphene to prepare multi-site sensing array (Zhu X, Liu D, Chen Q, et al]Chemical Communications,2016,52.), the ionic liquid modifies graphene, which undergoes a significant change in semiconductor properties from a p-type semiconductor to an n-type semiconductor. The array also has some identification capability for different gases. In addition, Nitzan Shauloff et al also used Metal ions to modify porous Graphene for detection of organophosphorous gas (Shauloff N, Terdal N L, Jelinek R. porous Graphene Oxide-Metal Ion Composite for Selective Sensing of organophosphorous Gases [ J]ACS Sensors,2020,5(6):1573-1581.), which has the advantages of high sensitivity, high selectivity, short response time and the like, but also works at higher temperature, thereby increasing the working cost and energy consumption.
In addition to graphene, some other two-dimensional materials having a similar structure to graphene, such as two-dimensional Transition Metal Sulfides (TMDs), hexagonal boron nitride (hBN), and two-dimensional inorganic compounds (Mxene), etc., have been recently considered as popular materials in the field of gas sensing by researchers due to their high carrier mobility and adjustable band gap. However, the conductivity of pure TMDs is poor, so researchers generally compound the TMDs with graphene to prepare a chemiresistive sensor. For example, Xinghui Houa et al prepared GO/MoS by hydrothermal method2Composite material (Hou X, Wang Z, Fan G, et al. structural three-dimensional MoS)2/GO hybrid nanostructures for triethylamine-sensing applications with high sensitivity and selectivity[J]Sensors and actors B Chemical,2020,317:128236.) that has good gas sensing properties for triethylamine, but the hydrothermal process is less reproducible and not a simple preparation method. Aimin Chen et al prepared GO/g-C by layer-by-layer assembly method3N4Composite materials (Chen A, Liu R, Peng X, et al.2D Hybrid Nanomaterials for Selective Detection of NO2 and SO2 Using"Light on and off"Strategy[J].Acs Applied Materials&Interfaces,2017: acsami.7b11244), g-C due to positively charged graphene3N4The material is negatively charged, so the two can be assembled layer by layer through electrostatic force. For two-dimensional materials with the same charge, the layer-by-layer assembly method cannot be directly used, and for this case, Pi-Guey Su et al use polyelectrolytes, such as polycation electrolytes PDDA, PAH, PEI, polyanion electrolytes PSS, etc. to perform electrostatic self-assembly (Su P G, Liao Z H.F. simulation of a flexible single-horn NH)3 gas sensor by layer-by-layer self-assembly of graphene oxide[J].Materials Chemistry&Physics,2019,224: 349-356.). Firstly, PSS/PAH two polyelectrolytes are used as a precursor layer, and then PAH polycation electrolyte is deposited between two layers of negative-charged GO films, so that the two layers of negative-charged films are successfully subjected to electrostatic self-assembly. However, the self-assembly usually requires tens of layers or even tens of layers, the actual operation process is complicated, and the error of manual operation is increased by the deposition of multiple layers of thin films, so that the self-assembly is not easy to be industrialized.
Therefore, this patent proposes a Graphene Oxide (GO) and two-dimensional molybdenum disulfide (2D-MoS)2) Or the metal ions (M) are subjected to liquid phase assembly with the assistance of PDDA, and the ternary composite gas sensing chip is obtained after hydrazine hydrate steam reduction. Wherein, GO-PDDA-MoS2Ternary composite material pair NO, H2S shows higher selectivity and sensitivity; and GO-PDDA-M has cross response to various inorganic gases and volatile organic gases. GO-PDDA-M and GO-PDDA-MoS constructed by various metal ions2After the gas sensing array is formed, healthy people and disease patients can be better identified through statistical methods such as principal component analysis and the like.
Disclosure of Invention
The invention provides a preparation method and an application method of a ternary composite gas sensing chip, which adopt the following technical scheme:
a preparation method of a ternary composite gas sensing chip comprises the following steps:
step one, mixing an isometric graphene oxide solution and a molybdenum disulfide solution, uniformly oscillating, adding a trace amount of PDDA, oscillating overnight on an oscillator, centrifugally washing for a plurality of times by using deionized water, and re-dispersing in the same amount of deionized water to obtain a self-assembly suspension material;
step two, mixing an isometric graphene oxide solution with a metal ion solution, uniformly oscillating, adding a trace amount of PDDA, oscillating overnight on an oscillator, centrifugally washing for a plurality of times by using deionized water, and re-dispersing in equivalent deionized water to obtain a self-assembly suspension material;
and step three, carrying out domain limitation on the ITO-PET interdigital electrode by using a PDMS film, carrying out oxygen plasma treatment on the electrode, dripping the self-assembly suspension material prepared in the step one or the step two on the electrode, drying the electrode on a heating plate, purging the electrode by using nitrogen, then placing the electrode into reducing steam for reduction for 10-20min at the temperature of 60-100 ℃ to obtain a ternary composite gas sensing chip unit, and forming the ternary composite gas sensing chip by using a single or a plurality of ternary composite gas sensing chip units.
Further, the metal ion solution is a chloride solution of high valence metal ions.
Further, the specific method of the second step is as follows: adding a 10mM chloride solution into an isometric 0.5mg/mL graphene oxide solution, uniformly oscillating, adding a trace amount of 1% Wt. PDDA, wherein the volume ratio of the added PDDA to the chloride solution is 0.03-0.08, oscillating overnight in an oscillator, centrifugally washing for 2-5 times by using deionized water, and re-dispersing in the same amount of deionized water to obtain the self-assembly suspension material.
Further, the chloride solution is one of ferric chloride, cobalt chloride, nickel chloride, copper chloride, cerium chloride, chromium chloride and manganese chloride.
Further, the specific method of the step one is as follows: adding 10mM molybdenum disulfide solution into 0.5mg/mL graphene oxide solution with the same volume, uniformly oscillating, then adding a trace of 1% Wt. PDDA, wherein the volume ratio of the added PDDA to the molybdenum disulfide solution is 0.03-0.08, oscillating overnight in an oscillator, then centrifugally washing for 2-5 times by using deionized water, and re-dispersing in the deionized water with the same volume to obtain the self-assembly suspension material.
Further, the molecular weight of PDDA ranges from less than 350 kDa.
Further, the reducing vapor is hydrazine hydrate vapor.
A ternary composite gas sensing material is prepared according to the first step of the preparation method of the ternary composite gas sensing chip, and the ternary composite gas sensing material is a multilayer structure of PDDA intercalated graphene oxide and molybdenum disulfide.
A ternary composite gas sensing material is prepared according to the second step of the preparation method of the ternary composite gas sensing chip, and the ternary composite gas sensing material is a multilayer structure of PDDA intercalated graphene oxide and metal ions.
A ternary composite gas sensing chip is prepared according to the preparation method of the ternary composite gas sensing chip, and comprises a single or a plurality of ternary composite gas sensing chip units.
Furthermore, the ternary composite gas sensing chip comprises a plurality of ternary composite gas sensing chip units, and each ternary composite gas sensing chip unit adopts different self-assembly suspension materials.
Further, the substrate of the ternary composite gas sensing chip is one of a flexible substrate formed by a PET film, a PEN film, a PI film and a PC film or a hard substrate formed by silicon, glass, ceramics and a PCB.
An application method of a ternary composite gas sensing chip comprises the following steps:
and placing the ternary composite gas sensing chip prepared by the preparation method of the ternary composite gas sensing chip in a gas flow cell for gas testing, wherein in the testing process, carrier gas is firstly introduced until the baseline tends to be stable, then sample gas is introduced at the same flow rate, and under a given voltage, the current value of the ternary composite gas sensing chip is tested by a picoampere meter to obtain data of the relation between the current value and time, and the sample gas is identified according to the data.
Furthermore, the ternary composite gas sensing chip comprises a plurality of different ternary composite gas sensing chip units, each ternary composite gas sensing chip unit can obtain data of the relation between the current value and the time, and the sample gas is identified according to the processing and analysis of a plurality of data.
Further, the carrier gas is background gas of the sample gas;
the sample gas is organic and/or inorganic volatile gas;
the sample gas is one or more of ammonia gas, hydrogen sulfide, nitric oxide, nitrogen dioxide and volatile organic gases such as acetone and isoprene.
Further, the carrier gas is pretreated environmental gas;
the sample gas is the gas exhaled by the human body after pretreatment;
the human body exhaled air is exhaled air of healthy individuals or exhaled air of disease patients;
the pretreatment mode is that the gas passes through a Teflon pipeline with the inner diameter of 2-10 mm and is soaked in ice water bath by 10-50 cm.
The three-element composite gas sensing chip, the preparation method and the application method thereof and the gas sensing material provided by the invention have the beneficial effects that the PDDA intercalated graphene is adopted, the combination of two-dimensional materials with negative charges in a liquid phase in a microscopic layer-by-layer assembly manner is realized, and the problems that the two-dimensional materials with the same charge cannot realize liquid phase assembly and the macroscopic layer-by-layer assembly process is complicated and difficult to industrialize are solved.
The three-element composite gas sensing chip, the preparation method and the application method thereof and the gas sensing material provided by the invention have the beneficial effects that the three-element composite gas sensing chip, the preparation method and the application method thereof and the gas sensing material are prepared by adopting PDDA intercalated graphene, the composite material has excellent electrochemical performance, and the response sensitivity to various gases is successfully improved.
The ternary composite gas sensing chip, the preparation method, the application method and the gas sensing material provided by the invention have the beneficial effects that the gas selectivity is successfully improved by utilizing the response difference of metal ions to different gases, and the recognition capability to different gases is realized by utilizing cross-sensitive response.
The three-element composite gas sensing chip, the preparation method and the application method thereof and the gas sensing material provided by the invention have the beneficial effects that the three-element composite gas sensing chip, the preparation method and the application method thereof and the gas sensing material are characterized in that the three-element composite sensing material is prepared by adopting PDDA intercalated graphene, and the sensors or the arrays thereof constructed by the composite material can realize the identification of different gases and the discrimination of exhaled gases of healthy people and patients.
Drawings
FIG. 1 is a flow chart of a method of making a ternary composite gas sensor chip of the present invention;
FIG. 2 is a scanning electron microscope image of the ternary composite gas sensing material prepared in example 1 of the present invention;
FIG. 3 is a graph showing the response kinetics of the ternary complex gas sensor chip prepared in example 1 of the present invention to different gases;
FIG. 4 is a graph showing the response kinetics of the ternary composite gas sensor chip prepared in example 3 of the present invention to different gases;
FIG. 5 is the statistics of the response values of the ternary composite gas sensing chip prepared in examples 2-8 of the present invention to different gases;
FIG. 6 shows the results of analyzing the main components of different gases by the ternary composite gas sensor chip prepared in examples 2 to 8 of the present invention;
fig. 7 is a test result of an application of the ternary complex gas sensing chip prepared by the present invention to detect human exhaled gas at room temperature.
Detailed Description
The invention is described in detail below with reference to the figures and the embodiments.
As shown in fig. 1, the present invention discloses a method for preparing a ternary composite gas sensor chip, comprising the following steps:
mixing an isometric graphene oxide solution and a metal ion solution, uniformly oscillating, adding a trace amount of PDDA (Poly dimethyl ammonium chloride), oscillating overnight on an oscillator, centrifugally washing for a plurality of times by using deionized water, and re-dispersing in the same amount of deionized water to obtain a self-assembly suspended material;
and secondly, limiting the ITO-PET interdigital electrode by using a PDMS film, carrying out oxygen plasma treatment on the electrode, dripping the self-assembly suspension material prepared in the first step on the electrode, drying the electrode on a heating plate, purging the electrode by using nitrogen, then placing the electrode into reducing steam for reducing for 10-20min at the temperature of 60-100 ℃ to obtain a ternary composite gas sensing chip unit, and forming a ternary composite gas sensing chip by using a single or a plurality of ternary composite gas sensing chip units.
In the first step, the range of the trace amount of PDDA is 10. mu.L-40. mu.L.
Specifically, the metal ion solution of one of the steps may be a chloride solution of a high valence metal ion, including but not limited to ferric chloride, cobalt chloride, nickel chloride, cupric chloride, cerium chloride, chromium chloride, and manganese chloride.
When the metal ion solution is a chloride solution, the specific method of the step one is as follows: adding a 10mM chloride solution into an isometric 0.5mg/mL graphene oxide solution, uniformly oscillating, adding a trace amount of 1% Wt. PDDA, wherein the volume ratio of the added PDDA to the chloride solution is 0.03-0.08, oscillating overnight in an oscillator, centrifugally washing for 2-5 times by using deionized water, and re-dispersing in the same amount of deionized water to obtain the self-assembly suspension material.
The invention discloses a preparation method of a ternary composite gas sensing chip, which comprises the following steps:
mixing an isometric graphene oxide solution and a molybdenum disulfide solution, uniformly oscillating, adding a trace amount of PDDA (Poly dimethyl ammonium chloride), oscillating overnight on an oscillator, centrifugally washing for a plurality of times by using deionized water, and re-dispersing in the same amount of deionized water to obtain a self-assembly suspended material;
and secondly, limiting the ITO-PET interdigital electrode by using a PDMS film, carrying out oxygen plasma treatment on the electrode, dripping the self-assembly suspension material prepared in the first step on the electrode, drying the electrode on a heating plate, purging the electrode by using nitrogen, then placing the electrode into reducing steam for reducing for 10-20min at the temperature of 60-100 ℃ to obtain a ternary composite gas sensing chip unit, and forming a ternary composite gas sensing chip by using a single or a plurality of ternary composite gas sensing chip units.
The specific method of the first step comprises the following steps: adding 10mM molybdenum disulfide solution into 0.5mg/mL graphene oxide solution with the same volume, uniformly oscillating, then adding a trace of 1% Wt. PDDA, wherein the volume ratio of the added PDDA to the molybdenum disulfide solution is 0.03-0.08, oscillating overnight in an oscillator, then centrifugally washing for 2-5 times by using deionized water, and re-dispersing in the deionized water with the same volume to obtain the self-assembly suspension material.
In the first step, the range of the trace amount of PDDA is 10. mu.L-40. mu.L.
In the present invention, the molecular weight of PDDA is in the range of less than 350 kDa. Further, the reducing vapor is hydrazine hydrate vapor, and it is understood that the reducing vapor may be replaced as necessary.
In a preferred embodiment, the substrate of the ternary complex gas sensor chip may be a flexible substrate formed of a PET (polyethylene terephthalate) film, a PEN (polyethylene naphthalate) film, a PI (polyimide) film, or a PC (polycarbonate) film, or may be a hard substrate formed of silicon, glass, ceramic, or a PCB.
The following are specific examples of the present invention.
Example 1:
the embodiment provides a preparation method for preparing a ternary composite gas sensing chip by adopting a molybdenum disulfide solution, which comprises the following specific steps:
step one, adding 0.5mL of 10mM molybdenum disulfide solution into an isometric 0.5mg/mL graphene oxide solution, uniformly oscillating, adding 15 mu L of 1% Wt. PDDA with the molecular weight less than 100kDa, oscillating overnight in an oscillator, centrifugally washing for 3 times by using deionized water, and re-dispersing in the equivalent deionized water to obtain a self-assembly suspension material;
and secondly, limiting the ITO-PET interdigital electrode by using a PDMS film, carrying out oxygen plasma treatment on the electrode, dripping 10 mu L of the self-assembly suspension material prepared in the first step on the electrode, drying the electrode on a heating plate, purging the electrode by using nitrogen, reducing the electrode in hydrazine hydrate steam at 80 ℃ for 15min to obtain a ternary composite gas sensing chip unit, and forming the ternary composite gas sensing chip by using one or more chip units. In the present embodiment, a scanning electron micrograph of the prepared ternary composite gas sensing material is shown in fig. 2.
Example 2:
the embodiment provides a preparation method for preparing a ternary composite gas sensing chip by adopting a cobalt chloride solution, which comprises the following specific steps:
step one, adding 0.5mL of 10mM cobalt chloride solution into an isometric 0.5mg/mL graphene oxide solution, uniformly oscillating, adding 15 mu L of 1% Wt. PDDA with the molecular weight of 100-200kDa, oscillating overnight in an oscillator, centrifugally washing for 3 times by using deionized water, and re-dispersing in the equivalent deionized water to obtain a self-assembly suspension material;
and secondly, limiting the ITO-PET interdigital electrode by using a PDMS film, carrying out oxygen plasma treatment on the electrode, dripping 10 mu L of the self-assembly suspension material prepared in the first step on the electrode, drying the electrode on a heating plate, purging the electrode by using nitrogen, reducing the electrode in hydrazine hydrate steam at 70 ℃ for 15min to obtain a ternary composite gas sensing chip unit, and forming the ternary composite gas sensing chip by using one or more chip units.
Example 3:
the embodiment provides a preparation method for preparing a ternary composite gas sensing chip by adopting a nickel chloride solution, which comprises the following specific steps:
step one, adding 0.5mL of 10mM nickel chloride solution into an isometric 0.5mg/mL graphene oxide solution, uniformly oscillating, adding 20 mu L of 1% Wt. PDDA with the molecular weight of 100-200kDa, oscillating overnight in an oscillator, centrifugally washing for 3 times by using deionized water, and re-dispersing in the equivalent deionized water to obtain a self-assembly suspension material;
and secondly, limiting the ITO-PET interdigital electrode by using a PDMS film, carrying out oxygen plasma treatment on the electrode, dripping 10 mu L of the self-assembly suspension material prepared in the first step on the electrode, drying the electrode on a heating plate, purging the electrode by using nitrogen, reducing the electrode in hydrazine hydrate steam at 80 ℃ for 20min to obtain a ternary composite gas sensing chip unit, and forming the ternary composite gas sensing chip by using one or more chip units.
Example 4:
the embodiment provides a preparation method for preparing a ternary composite gas sensing chip by using a copper chloride solution, which comprises the following specific steps:
step one, adding 0.5mL of 10mM copper chloride solution into an isometric 0.5mg/mL graphene oxide solution, uniformly oscillating, adding 25 mu L of 1% Wt. PDDA with the molecular weight of 100-200kDa, oscillating overnight in an oscillator, centrifugally washing for 3 times by using deionized water, and re-dispersing in the equivalent deionized water to obtain a self-assembly suspension material;
and step two, performing confinement on the ITO-PET interdigital electrode by using a PDMS film, performing oxygen plasma treatment on the electrode, dripping 10 mu L of the self-assembly suspension material prepared in the step one on the electrode, drying the electrode on a heating plate, purging the electrode by using nitrogen, reducing the electrode in hydrazine hydrate steam at 90 ℃ for 10min to obtain a ternary composite gas sensing chip unit, and forming the ternary composite gas sensing chip by using one or more chip units.
Example 5:
the embodiment provides a preparation method for preparing a ternary composite gas sensing chip by adopting a cerium chloride solution, which comprises the following specific steps:
step one, adding 0.5mL of 10mM cerium chloride solution into an isometric 0.5mg/mL graphene oxide solution, uniformly oscillating, adding 30 mu L of 1% Wt. PDDA with the molecular weight of 200-350kDa, oscillating overnight in an oscillator, centrifugally washing for 3 times by using deionized water, and re-dispersing in the equivalent deionized water to obtain a self-assembly suspension material;
and secondly, limiting the ITO-PET interdigital electrode by using a PDMS film, carrying out oxygen plasma treatment on the electrode, dripping 10 mu L of the self-assembly suspension material prepared in the first step on the electrode, drying the electrode on a heating plate, purging the electrode by using nitrogen, reducing the electrode in hydrazine hydrate steam at 100 ℃ for 15min to obtain a ternary composite gas sensing chip unit, and forming the ternary composite gas sensing chip by using one or more chip units.
Example 6:
the embodiment provides a preparation method for preparing a ternary composite gas sensing chip by adopting a chromium chloride solution, which comprises the following specific steps:
step one, adding 0.5mL of 10mM chromium chloride solution into an isometric 0.5mg/mL graphene oxide solution, uniformly oscillating, adding 35 mu L of 1% Wt. PDDA with the molecular weight of 200-350kDa, oscillating overnight in an oscillator, centrifugally washing for 3 times by using deionized water, and re-dispersing in the equivalent deionized water to obtain a self-assembly suspension material;
and secondly, limiting the ITO-PET interdigital electrode by using a PDMS film, carrying out oxygen plasma treatment on the electrode, dripping 10 mu L of the self-assembly suspension material prepared in the first step on the electrode, drying the electrode on a heating plate, purging the electrode by using nitrogen, reducing the electrode in hydrazine hydrate steam at 70 ℃ for 20min to obtain a ternary composite gas sensing chip unit, and forming the ternary composite gas sensing chip by using one or more chip units.
Example 7:
the embodiment provides a preparation method for preparing a ternary composite gas sensing chip by adopting a manganese chloride solution, which comprises the following specific steps:
step one, adding 0.5mL of 10mM manganese chloride solution into an isometric 0.5mg/mL graphene oxide solution, uniformly oscillating, adding 40 mu L of 1% Wt. PDDA with the molecular weight less than 100kDa, oscillating overnight in an oscillator, centrifugally washing for 3 times by using deionized water, and re-dispersing in the equivalent deionized water to obtain a self-assembly suspension material;
and secondly, limiting the ITO-PET interdigital electrode by using a PDMS film, carrying out oxygen plasma treatment on the electrode, dripping 10 mu L of the self-assembly suspension material prepared in the first step on the electrode, drying the electrode on a heating plate, purging the electrode by using nitrogen, reducing the electrode in hydrazine hydrate steam at 80 ℃ for 15min to obtain a ternary composite gas sensing chip unit, and forming the ternary composite gas sensing chip by using one or more chip units.
Example 8:
the embodiment provides a preparation method for preparing a ternary composite gas sensing chip by using a ferric chloride solution, which comprises the following specific steps:
step one, adding 0.5mL of 10mM ferric chloride solution into an isometric 0.5mg/mL graphene oxide solution, uniformly oscillating, adding 10 mu L of 1% Wt. PDDA with the molecular weight less than 100kDa, oscillating overnight in an oscillator, centrifugally washing for 3 times by using deionized water, and re-dispersing in the equivalent deionized water to obtain a self-assembly suspension material;
and step two, performing confinement on the ITO-PET interdigital electrode by using a PDMS film, performing oxygen plasma treatment on the electrode, dripping 10 mu L of the self-assembly suspension material prepared in the step one on the electrode, drying the electrode on a heating plate, purging the electrode by using nitrogen, reducing the electrode in hydrazine hydrate steam at 60 ℃ for 10min to obtain a ternary composite gas sensing chip unit, and forming the ternary composite gas sensing chip by using one or more chip units.
The application also discloses a ternary composite gas sensing material which is prepared according to the first step of the preparation method and has a multilayer structure. Specifically, the ternary composite gas sensing material is a multilayer structure of PDDA intercalated graphene oxide and metal ions or a multilayer structure of PDDA intercalated graphene oxide and molybdenum disulfide.
The application also discloses a ternary composite gas sensing chip which is prepared according to the preparation method of the ternary composite gas sensing chip, and the ternary composite gas sensing chip comprises one or more ternary composite gas sensing chip units.
Preferably, the ternary composite gas sensing chip comprises a plurality of ternary composite gas sensing chip units, and each ternary composite gas sensing chip unit adopts different self-assembly suspension materials.
The application also discloses an application method of the ternary composite gas sensing chip, which comprises the following steps:
and placing the ternary composite gas sensing chip prepared by the preparation method of the ternary composite gas sensing chip in a gas flow cell for gas testing, wherein in the testing process, carrier gas is firstly introduced until the baseline tends to be stable, then sample gas is introduced at the same flow rate, and under a given voltage, the current value of the ternary composite gas sensing chip is tested by a picoampere meter to obtain data of the relation between the current value and time, and the sample gas is identified according to the data.
Specifically, the carrier gas is a background gas of the sample gas. The sample gas is an organic and/or inorganic volatile gas. The sample gas is one or more of ammonia gas, hydrogen sulfide, nitric oxide, nitrogen dioxide and volatile organic gases such as acetone and isoprene.
As another mode, the carrier gas is a pretreated environmental gas, and the sample gas is a pretreated human body exhalation gas. In the application, the exhaled air of the human body is exhaled air of a healthy individual or exhaled air of a patient with simulated asthma disease, so that the exhaled air of the healthy individual and the exhaled air of the patient with simulated asthma disease through the healthy individual are detected respectively, and the detection results have great difference. Specifically for later analysis. The pretreatment mode is that the gas passes through a Teflon pipeline with the inner diameter of 2-10 mm and is soaked in ice water bath by 10-50 cm. It will be appreciated that the human exhalation may also be that of healthy individuals and that of other types of patients with airway inflammation.
Specifically, the following description is made by detecting and identifying organic/inorganic volatile compounds at room temperature by the ternary composite gas sensing chip prepared in the above example 1:
as an example, the ternary composite gas sensing chip prepared by using molybdenum disulfide in example 1 is used for detecting acetone/isoprene/ammonia/hydrogen sulfide/nitric oxide: the ternary composite gas sensing chip is placed in a gas flow cell, in the testing process, carrier gas is firstly introduced until a base line tends to be stable, then acetone, isoprene, ammonia gas, hydrogen sulfide or nitric oxide with different concentrations is introduced at the same flow rate, and the current value flowing through the ternary composite gas sensing chip is tested through a picoammeter under the voltage of 1V to obtain data of the relation between the current value and time, so that the response value of the ternary composite gas sensing chip prepared by molybdenum disulfide to different sample gases is known.
The kinetic curves for the detection of 1-10ppm acetone standard gas are shown in FIG. 3a, the kinetic curves for the detection of 1-10ppm ammonia standard gas are shown in FIG. 3b, the kinetic curves for the detection of 2-15ppm isoprene standard gas are shown in FIG. 3c, the kinetic curves for the detection of 0.05-1ppm hydrogen sulfide standard gas are shown in FIG. 3d, and the kinetic curves for the detection of 0.05-1ppm nitric oxide standard gas are shown in FIG. 3 e. The detection of five gases shows that the ternary composite gas sensing chip can generate higher response to the five gases and has higher sensitivity.
The following specific description is made by detecting and identifying organic/inorganic volatile compounds at room temperature by using ternary composite gas sensor chips prepared from ferric chloride, cobalt chloride, nickel chloride, copper chloride, cerium chloride, chromium chloride and manganese chloride in the above examples 2 to 8 respectively:
as an example, the ternary composite gas sensing chips prepared from ferric chloride, cobalt chloride, nickel chloride, copper chloride, cerium chloride, chromium chloride and manganese chloride in examples 2 to 8 were used for detection of acetone/isoprene/ammonia/hydrogen sulfide/nitric oxide, respectively: the ternary composite gas sensing chip is placed in a gas flow cell, in the testing process, carrier gas is firstly introduced until a base line tends to be stable, then acetone, isoprene, ammonia gas, hydrogen sulfide or nitric oxide with different concentrations is introduced at the same flow rate, the current value flowing through the ternary composite gas sensing chip is tested through a picoammeter under the voltage of 1V, and data of the relation between the current value and time are obtained, so that the response values of the ternary composite gas sensing chip adopting ferric chloride, cobalt chloride, nickel chloride, copper chloride, cerium chloride, chromium chloride and manganese chloride to different sample gases are known.
Taking the ternary composite gas sensing chip prepared by nickel manganese chloride in example 3 as an example, the kinetic curve for detecting 1-10ppm acetone standard gas is shown in fig. 4a, the kinetic curve for detecting 1-10ppm ammonia standard gas is shown in fig. 4b, the kinetic curve for detecting 2-15ppm isoprene standard gas is shown in fig. 4c, the kinetic curve for detecting 0.05-1ppm hydrogen sulfide standard gas is shown in fig. 4d, and the kinetic curve for detecting 0.05-1ppm nitric oxide standard gas is shown in fig. 4 e. The results of the detection of the ternary composite gas sensing chip prepared from ferric chloride, cobalt chloride, nickel chloride, copper chloride, cerium chloride, chromium chloride and manganese chloride on the five gases are shown in fig. 5, and the results show that the ternary composite gas sensing chip prepared from ferric chloride, cobalt chloride, nickel chloride, copper chloride, cerium chloride, chromium chloride and manganese chloride can generate responses to the five gases, but the responses are different in magnitude, and the response mode of the cross response can be used for identifying and distinguishing different gases. After the response values are normalized, principal component analysis is performed, and as can be seen from fig. 6, the ternary composite gas sensing chip prepared by using ferric chloride, cobalt chloride, nickel chloride, copper chloride, cerium chloride, chromium chloride and manganese chloride can better distinguish four gases.
The following is a detailed description of the application method of the ternary complex gas sensor chip prepared in the above example 1 for detecting exhaled gas of human body at room temperature:
as an example, when the ternary composite gas sensing chip prepared in example 1 is used for detecting human exhaled breath, firstly, the empty stomach exhaled breath of healthy individuals is collected in a 2L perfluoroethylene propylene copolymer (FEP) sampling bag under ventilation environment, and a certain amount of H is injected into a part of collected exhaled breath of healthy individuals2The S and NO standard gases are used as the exhaled gas of a simulated asthma patient to ensure that H is2The final S and NO concentrations were 15ppb and 50ppb, respectively, while local ambient gas was collected as the carrier gas. When collecting gas (including environmental gas and expired gas of healthy people), the gas is pretreated by a Teflon pipeline with the inner diameter of 5mm, which is immersed in ice-water bath by 25 cm. The ternary composite gas sensing chip is placed in a gas flow cell, in the testing process, pretreated environmental gas is firstly introduced until a base line tends to be stable, then pretreated human body exhaled gas is introduced at the same flow rate (exhaled gas of a healthy person and exhaled gas of a simulated asthma patient are detected independently), the current value is tested through a multichannel skin ampere meter under the voltage of 1V, data of the relation between the current value and time are obtained, and the healthy person and the disease patient are distinguished according to the data. The results are shown in FIG. 7The response values of the exhaled air of the healthy individual and the simulated asthma patient on the ternary composite sensing chip are obviously different, and the ternary composite material has application potential for identifying the asthma patient.
The foregoing illustrates and describes the principles, general features, and advantages of the present invention. It should be understood by those skilled in the art that the above embodiments do not limit the present invention in any way, and all technical solutions obtained by using equivalent alternatives or equivalent variations fall within the scope of the present invention.