CN113311025B

CN113311025B - Preparation method of novel intelligent gas sensing material suitable for indoor ammonia gas detection

Info

Publication number: CN113311025B
Application number: CN202110787927.4A
Authority: CN
Inventors: 关莹; 曹光; 黄群浩; 郇伟伟
Original assignee: Zhejiang A&F University ZAFU
Current assignee: Zhejiang A&F University ZAFU
Priority date: 2021-07-13
Filing date: 2021-07-13
Publication date: 2023-06-27
Anticipated expiration: 2041-07-13
Also published as: CN113311025A

Abstract

The invention relates to a preparation method of a high-sensitivity flexible gas sensing material suitable for indoor ammonia concentration detection, which is characterized in that polyaniline is synthesized by a gas phase polymerization method, flexible cotton gauze is used as a carrier, graphene and polylactic acid are used for wrapping cotton yarn fibers, and the polyaniline is synthesized on a fabric-based flexible substrate to assemble the flexible gas sensing material. The flexible gas sensing material can accurately and rapidly detect the concentration change of ammonia, can detect gas in various gas environments, has the advantages of high sensitivity, high stability, convenience in preparation, greenness, no toxicity, flexibility, no space limitation and the like, and can be applied to the fields of indoor decoration, environment monitoring, medical equipment, agricultural production and the like.

Description

Preparation method of novel intelligent gas sensing material suitable for indoor ammonia gas detection

Technical Field

The invention relates to the design and development of an intelligent flexible sensing material for detecting indoor ammonia gas, in particular to a preparation method of a novel intelligent flexible gas sensing material with high sensitivity to ammonia gas.

Background

People cannot leave the air environment, and a clean air environment is an important guarantee for human health, safety, work and life. In modern decoration, harmful substances, such as indoor decoration materials, furniture and concrete for building construction, release ammonia inevitably. Ammonia is usually inhaled into human body in a gas form, ammonia entering alveoli can denature tissue proteins, saponify tissue fat, destroy cell membrane structures and weaken the resistance of human body to diseases, so that the detection of the indoor ammonia concentration is very important, and most of the current detection means of ammonia are rapid and convenient gas sensors. The sensing materials in the traditional gas sensor are noble metals or metal oxides, the detection sensitivity is higher, but the preparation process is complex and the manufacturing cost is high, in addition, the metal is not flexible, and the ammonia gas detection in a complex space environment is difficult to meet, so that the development of a novel flexible gas sensing material preparation method is necessary.

PANI is a typical p-type conductive polymer with simple fabrication, good environmental stability, excellent conductivity, and an adjustable conductivity response window, and is thus widely used in the fabrication of various electrical, optoelectronic, electrochemical, and sensing devices, and is becoming a hotspot of increasing interest.

Graphene is a material composed of carbon atoms and sp ² The two-dimensional carbon nanomaterial with hexagonal lattice and the hybridized orbit has good stability and excellent conductivity. In the partially protonated PANI, the graphene can be used as an electron acceptor, so that the PANI is wrapped on the surface of the graphene by a gas phase polymerization method, the density of surface states is reduced, and the conductivity of the material is greatly improved. Graphene, PANI composites are therefore considered ideal conductive materials.

The flexible material has the characteristics of good flexibility, elasticity, 3D multilayer structure and the like. The cotton gauze has the advantages of good degradability, low economic cost, wide material sources and the like. PLA forms a layer of film on cotton yarn fiber surface of cotton gauze, very big reinforcing cotton gauze's toughness, also makes graphene load on cotton yarn cloth surface steadily simultaneously, has solved the unstable problem of graphene adhesion on cotton gauze.

The invention can successfully prepare the novel high-sensitivity flexible gas sensing material suitable for detecting the concentration of the indoor ammonia gas. The excellent performance of the sensing material enables the novel flexible gas sensing material to obtain high sensitivity, high stability and high economical efficiency. Compared with other ammonia gas sensing materials, the sensing material has the advantages of lower energy consumption, more intellectualization, better space adaptability and unique advantages in the aspect of indoor ammonia gas detection. Meanwhile, the method has great potential application value in the fields of harmful gas detection, medical equipment, wearable electronic products, agricultural production, aerospace and the like.

Disclosure of Invention

The invention aims to provide a preparation method of a novel intelligent gas sensing material, which is simple in preparation, green, nontoxic and convenient for mass production.

A preparation method of a novel high-sensitivity flexible gas sensing material suitable for indoor ammonia gas detection comprises the following specific steps:

(1) Uniformly mixing PLA, chloroform and graphene in a proper mass ratio;

(2) Ultrasonic treating the mixed solution obtained in step (1) for 30min, and washing with ethanol solution to obtain 4.0X14.0 cm solution ² Soaking cotton yarn cloth material in the mixed solution after ultrasonic treatment, standing for proper time, taking out, and airing for later use;

(3) Ammonium Persulfate (APS) with proper mass is added into a certain volume of 2.0mol/L hydrochloric acid (HCl) solution, and the cotton gauze material dried in the step (2) is immersed into the solution and is kept stand for 1h.

(4) Adding 20.0mL of 2.0mol/L HCl solution and 400.0 mu L aniline into a glass bottle, covering the cotton gauze material treated in the step (3) on the bottle mouth of the glass bottle, further sealing with a preservative film, covering a cover, placing the glass bottle in an ice bath for reacting for a proper time, and then placing the prepared sensing material into a baking oven at 40 ℃ for drying for 12 hours to obtain the product.

The appropriate mass ratio in the step (1) is 1:80:1 (0.370 g PLA, 20.0mL chloroform, 0.370g graphene), 1:400:5 (0.074 g PLA, 20.0mL chloroform, 0.370g graphene).

The cotton yarn cloth material in the step (2) is kept stand in the mixed solution for 0.5-1h.

The volume of HCl in the step (3) is 10.0mL, and the mass of APS is 0.18-0.20g.

The proper time for the ice bath of the glass bottle in the step (4) is 2-4h.

The gas sensor material obtained by the invention uses a field emission scanning electron microscope (FF-SEM), and the result is as follows:

(1) Field emission scanning electron microscopy (FF-SEM) test, see FIG. 1.

The novel flexible gas sensing material prepared by the invention can realize sensitive and accurate determination of ammonia gas, and has wide application prospects in the aspects of medical care, wearable equipment and the like.

The invention has the beneficial effects that:

(1) The invention uses cotton gauze with wide sources and simple preparation as a substrate raw material, and has the advantages of green, environment protection and degradability.

(2) The invention uses PANI conductive polymer as sensing material, which can detect gas at normal temperature.

(3) The intelligent gas sensing material prepared by the invention has stable conductivity, high gas sensing precision and simple preparation method, and is beneficial to large-scale production.

Drawings

FIG. 1 is a scanning electron microscope image of the surface morphology of a cotton gauze loaded graphene and polyaniline novel intelligent gas sensing material;

Detailed Description

The invention is further illustrated below in conjunction with specific examples. These examples are only for illustrating the present invention and are not intended to limit the scope of the present invention. Further, after reading the teachings of the present invention, those skilled in the art may make various changes or modifications to the present invention, which equivalent forms also fall within the scope of the claims appended hereto.

Example 1

20.0mL of chloroform, 0.370g of PLA, and 0.370g of graphene were mixed, and the mixture was sonicated for 30min. Immersing cotton gauze washed by ethanol into the mixed solution, standing for 0.5h, taking out, and airing for standby. 10.0mL of 2.0mol/L HCl and 0.18g of APS were mixed, and the treated cotton gauze was immersed in the HCl solution of APS and allowed to stand for 1 hour. Respectively taking 20.0mL of HCl with the concentration of 2.0mol/L and 400 mu L of aniline in a glass bottle, uniformly mixing, covering the bottle mouth with soaked cotton gauze, sealing with a preservative film, and covering with a cover. And placing the reaction glass bottle in an ice bath for reaction for 2 hours, and then placing the prepared sensing material in a baking oven at 40 ℃ for baking for 12 hours to obtain the product.

Example 2

20mL of chloroform, 0.370g of PLA, and 0.37g of graphene were mixed, and the mixture was sonicated for 30min. Immersing cotton gauze washed by ethanol into the mixed solution, standing for 1h, taking out, and airing for standby. 10mL of 2mol/L HCl and 0.20g of APS were mixed, and the treated cotton gauze was immersed in an APS HCl solution and allowed to stand for 1 hour. Respectively taking 20mL of 2mol/L HCl and 400 mu L of aniline in a glass bottle, uniformly mixing, covering the bottle mouth with soaked cotton gauze, sealing with a preservative film, and covering with a cover. And placing the reaction glass bottle in an ice bath for reaction for 2 hours, and then placing the prepared sensing material in a baking oven at 40 ℃ for baking for 12 hours to obtain the product.

Example 3

20mL of chloroform, 0.370g of PLA, and 0.37g of graphene were mixed, and the mixture was sonicated for 30min. Immersing cotton gauze washed by ethanol into the mixed solution, standing for 1h, taking out, and airing for standby. 10ml of 2mol/L HCl and 0.18g of APS were mixed, and the treated cotton gauze was immersed in an APS HCl solution and allowed to stand for 1 hour. Respectively taking 20ml of 2mol/L HCl and 400 mu L of aniline in a glass bottle, uniformly mixing, covering the bottle mouth with soaked cotton gauze, sealing with a preservative film, and covering with a cover. And placing the reaction glass bottle in an ice bath for reaction for 4 hours, and then placing the prepared sensing material in a baking oven at 40 ℃ for baking for 12 hours to obtain the product.

Example 4

20mL of chloroform, 0.074g of PLA, and 0.37g of graphene were mixed, and the mixture was sonicated for 30min. Immersing cotton gauze washed by ethanol into the mixed solution, standing for 0.5h, taking out, and airing for standby. 10mL of 2mol/L HCl and 0.18g of APS were mixed, and the treated cotton gauze was immersed in an APS HCl solution and allowed to stand for 1 hour. Respectively taking 20mL of 2mol/L HCl and 400 mu L of aniline in a glass bottle, uniformly mixing, covering the bottle mouth with soaked cotton gauze, sealing with a preservative film, and covering with a cover. And placing the reaction glass bottle in an ice bath for reaction for 2 hours, and then placing the prepared sensing material in a baking oven at 40 ℃ for baking for 12 hours to obtain the product.

Example 5

20mL of chloroform, 0.074g of PLA, and 0.37g of graphene were mixed, and the mixture was sonicated for 30min. Immersing cotton gauze washed by ethanol into the mixed solution, standing for 1h, taking out, and airing for standby. 10mL of 2mol/L HCl and 0.20g of APS were mixed, and the treated cotton gauze was immersed in an APS HCl solution and allowed to stand for 1 hour. Respectively taking 20ml of 2mol/L HCl and 400 mu L of aniline in a glass bottle, uniformly mixing, covering the bottle mouth with soaked cotton gauze, sealing with a preservative film, and covering with a cover. And placing the reaction glass bottle in an ice bath for reaction for 2 hours, and then placing the prepared sensing material in a baking oven at 40 ℃ for baking for 12 hours to obtain the product.

Example 6

20mL of chloroform, 0.074g of PLA, and 0.37g of graphene were mixed, and the mixture was sonicated for 30min. Immersing cotton gauze washed by ethanol into the mixed solution, standing for 1h, taking out, and airing for standby. 10mL of 2mol/L HCl and 0.18g of APS were mixed, and the treated cotton gauze was immersed in an APS HCl solution and allowed to stand for 1 hour. Respectively taking 20mL of 2mol/L HCl and 400 mu L of aniline in a glass bottle, uniformly mixing, covering the bottle mouth with soaked cotton gauze, sealing with a preservative film, and covering with a cover. And placing the reaction glass bottle in an ice bath for reaction for 4 hours, and then placing the prepared sensing material in a baking oven at 40 ℃ for baking for 12 hours to obtain the product.

Claims

1. The preparation method of the high-sensitivity flexible gas sensing material suitable for indoor ammonia concentration detection is characterized by comprising the following steps of:

(1) Uniformly mixing PLA, chloroform and graphene in a proper mass ratio;

(2) Ultrasonic treating the mixed solution obtained in step (1) for 30min, and washing with ethanol solution to obtain 4.0X14.0. 4.0cm ² Soaking cotton yarn cloth material in the mixed solution after ultrasonic treatment, standing for proper time, taking out, and airing for later use;

(3) Adding Ammonium Persulfate (APS) with proper mass into a certain volume of 2.0mol/L hydrochloric acid (HCl) solution, immersing the cotton gauze material dried in the step (2) into the solution, and standing for 1 h;

(4) Adding 20.0mL of 2.0mol/L HCl solution and 400.0 mu L aniline into a glass bottle, covering the cotton gauze material treated in the step (3) on the bottle mouth of the glass bottle, further sealing with a preservative film, covering a cover, placing the glass bottle in an ice bath for reacting for a proper time, and then placing the prepared sensing material into a baking oven at 40 ℃ for drying for 12h to obtain a high-sensitivity flexible gas sensing material; the appropriate mass ratio in the step (1) is 1:80:1 or 1:400:5.

2. the method of manufacturing according to claim 1, characterized in that: the cotton gauze material in the step (2) is kept stand in the mixed solution for 0.5-1h.

3. The method of manufacturing according to claim 1, characterized in that: the volume of HCl in the step (3) is 10.0mL, and the mass of APS is 0.18-0.20g.

4. The method of manufacturing according to claim 1, characterized in that: the proper time for the ice bath of the glass bottle in the step (4) is 2-4h.