CN117550648A - Porous MXene-Fe 2 O 3 Preparation method and application of composite material - Google Patents

Porous MXene-Fe 2 O 3 Preparation method and application of composite material Download PDF

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CN117550648A
CN117550648A CN202311516864.4A CN202311516864A CN117550648A CN 117550648 A CN117550648 A CN 117550648A CN 202311516864 A CN202311516864 A CN 202311516864A CN 117550648 A CN117550648 A CN 117550648A
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mxene
composite material
gas
sea urchin
layer
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侯明
江国鑫
郭胜惠
杨黎
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Kunming University of Science and Technology
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Abstract

The invention belongs to the technical field of gas-sensitive materials, and relates to a porous MXene-Fe 2 O 3 A preparation method and application of the composite material. By mixing single/few layer MXene sol material with sea urchin-like Fe modified by polydiallyl dimethyl ammonium chloride (PDDA) 2 O 3 After mixing and stirring vigorously, carrying out bidirectional freeze drying under the condition of less oxygen to prepare the porous MXene-Fe 2 O 3 A composite material. After being processed by a bidirectional freeze drying technology, MXene-Fe 2 O 3 The surface of the composite material is porous, the specific surface area of the material is increased, thereby providing more active sites for gas-sensitive reaction and improving the gas sensitivity of the materialThe gas-sensitive response value is pure Fe 2 O 3 And Ti is 3 C 2 T x 2 times and 3.2 times the gas-sensitive properties.

Description

Porous MXene-Fe 2 O 3 Preparation method and application of composite material
Technical Field
The present invention belongs to the field of gas-sensitive material technologyIn the field of surgery, more particularly to a porous MXene-Fe 2 O 3 A preparation method and application of the composite material.
Background
Ammonia (NH) 3 ) Mainly from concrete additives used in building construction, such as concrete antifreezing agents and high-alkali concrete expanding agents used in winter, early strength agents and the like. Because the components of the substances are ammonia substances, the ammonia substances can be reduced to NH along with the change of the factors such as ambient temperature, humidity and the like 3 Causing environmental pollution. If the human body inhales NH for a long time 3 Can cause pulmonary edema, respiratory distress syndrome and other diseases, and cause serious harm to human bodies. Thus, development and preparation of NH having excellent properties 3 Gas sensitive materials with gas sensitive properties have been an important subject of great interest.
At present, the metal oxide semiconductor compounded with MXene mainly comprises ZnO and SnO 2 Mainly, the limited MXene-based composite material limits the development of MXene in the field of gas-sensitive sensing, and the low gas-sensitive performance of the gas-sensitive sensor limits the practical application of the gas-sensitive sensor. Thus, low temperature high response NH was developed 3 The sensor is particularly important.
Disclosure of Invention
The invention aims to provide a porous MXene-Fe 2 O 3 Preparation method and application of composite material to solve the problems in the prior art, develop and prepare excellent NH 3 A gas sensitive material with gas sensitive sensing performance.
In order to achieve the above purpose, the present invention provides the following technical solutions:
one of the technical schemes of the invention is as follows: providing a porous MXene-Fe 2 O 3 The preparation method of the composite material comprises the following steps:
single-layer/few-layer MXene sol material and sea urchin-shaped Fe modified by PDDA (polymer dispersed architecture) 2 O 3 Mixing and then vigorously stirring under the protection of inert atmosphere to obtain a mixed solution;
the mixed solution is subjected to bidirectional freeze drying under vacuum condition, and the porous MXene-Fe is obtained 2 O 3 A composite material;
the single-layer/few-layer MXene sol material is Nb 2 CT x 、Nb 3 C 4 T x 、Ta 2 CT x 、Ta 4 C 3 T x 、Ti 2 CT x And Ti is 3 C 2 T x At least one of them.
Further, the preparation method of the single-layer/few-layer MXene sol material comprises the following steps:
mixing fluorine salt and HCl solution, adding MAX material, stirring under the condition of oil bath to perform liquid phase etching, and collecting solid products;
and cleaning the solid product, performing ultrasonic treatment in water, and centrifuging to obtain the single-layer/few-layer MXene sol material.
Preferably, the MAX material comprises Nb 2 AlC、Nb 3 AlC 4 、Ta 2 AlC、Ta 4 AlC 3 、Ti 2 AlC and Ti 3 AlC 2 At least one of them.
Preferably, the concentration of the HCl solution is 9mol/L.
Preferably, the fluoride salt is KF and/or LiF.
Preferably, the mass/volume ratio of MAX material, fluoride salt and HCl is 1g:1g:10mL.
Preferably, the temperature of the oil bath is 35-55 ℃ and the time is 12-36 h.
Preferably, the stirring rate is 450 to 550rpm.
Preferably, the washing is to be neutral by using water and/or absolute ethanol.
Preferably, the power of the ultrasonic treatment is 100-800W, and the time is 20-50 min.
Preferably, the speed of centrifugation is 3500-5500 rpm, and the time is 30-60min.
Further, the sea urchin-like Fe 2 O 3 The preparation method of (2) comprises the following steps:
FeCl is added 3 ·6H 2 O and (NH) 4 ) 2 SO 4 Dissolving in water, mixing, stirring, reacting under hydrothermal condition, collectingA solid product;
cleaning and drying the solid product, and sintering under the air condition to obtain sea urchin-shaped Fe 2 O 3 A material.
Preferably, the FeCl 3 ·6H 2 O、(NH 4 ) 2 SO 4 And water in a molar/volume ratio of 0.015 to 0.030mol:0.76 to 0.86mmol:30 to 50mL.
Preferably, the reaction temperature under the hydrothermal condition is 120-160 ℃ and the reaction time is 12-36 h.
Preferably, the sintering temperature is 600-800 ℃ and the sintering time is 2-4 h.
Preferably, the stirring is magnetic stirring, and the rotating speed is 350-550 rpm.
Preferably, the washing is to be neutral by using water and/or absolute ethanol.
Preferably, the temperature of the drying is 80-100 ℃ and the time is 8-12 h.
Further, the method for modifying polydiallyl dimethyl ammonium chloride (PDDA) comprises the following steps: the sea urchin-like Fe 2 O 3 Dispersing into polydiallyl dimethyl ammonium chloride, ultrasonically filtering, washing, and drying to obtain the PDDA modified sea urchin-shaped Fe 2 O 3 。
Preferably, the PDDA is mixed with sea urchin-like Fe 2 O 3 The volume/mass ratio of (2) is 300-500 mL/1 g.
Preferably, the power of the ultrasonic wave is 180W, and the time is 3-5 h.
Preferably, the drying temperature is 70-90 ℃ and the drying time is 12-16 h.
Further, the single-layer/few-layer MXene sol material and PDDA modified sea urchin-shaped Fe 2 O 3 The volume mass ratio of (2) is 5-30 mL:1-3 g.
Further, the temperature of the bidirectional freeze drying is-60 to-80 ℃ and the time is 40 to 72 hours.
Further, the inert atmosphere includes a nitrogen atmosphere or an argon atmosphere.
Further, the vacuum pressure is 0.1 to 0.3Pa.
Further, the time of the vigorous stirring is 10-30 hours.
The second technical scheme of the invention is as follows: provides a porous MXene-Fe prepared by the method 2 O 3 A composite material.
The third technical scheme of the invention: providing a porous MXene-Fe as described above 2 O 3 The application of the composite material in the preparation of the gas-sensitive sensing material.
The fourth technical scheme of the invention: a gas sensor is provided, the raw material comprises the porous MXene-Fe 2 O 3 A composite material.
The fifth technical scheme of the invention is as follows: the preparation method of the gas sensor comprises the following steps:
the porous MXene-Fe is treated by an organic solvent (ethanol) as a grinding medium 2 O 3 Grinding the composite material, printing the ground composite material on a ceramic plate of a platinized electrode, and sintering the composite material for 2 to 4 hours under the protection of argon atmosphere to obtain the gas sensor.
Further, the sintering temperature is 350-550 ℃.
It is worth to say that, the ethanol of the above-mentioned organic solvent is regarded as grinding media, ethanol concentration and additive amount can carry on the adaptive adjustment according to actual grinding situation, preferably, the ethanol of said organic solvent uses 10-20 ml, the volume fraction is 99.7%; the polishing particle size is not particularly limited, and the polishing time and the final polishing particle size are selected according to the printing state, and the polishing time is preferably 10 to 20 minutes.
The sixth technical scheme of the invention: providing the gas sensor in NH 3 Application in the detection of gases.
Compared with the prior art, the technical scheme has the following beneficial effects:
the invention uses single-layer/few-layer MXene and sea urchin-shaped Fe 2 O 3 The ultra-light Ti is successfully prepared by a bidirectional freeze drying technology 3 C 2 T x -Fe 2 O 3 Thin layer porous compositeComposite material, sea urchin-like Fe 2 O 3 Is distributed on the surface and the interlayer of the single-layer/few-layer MXene sol material. The gas-sensitive test result shows that the sea urchin-shaped Fe 2 O 3 With Ti 3 C 2 T x Can obviously improve the gas-sensitive response of the material, and can perform the reaction on 100ppm NH at 100 DEG C 3 The gas-sensitive response value is 56.2%, which is pure Fe respectively 2 O 3 And Ti is 3 C 2 T x 2 times and 3.2 times the gas-sensitive properties. The improvement in gas-sensitive properties is attributed to Ti 3 C 2 T x After the bidirectional freeze drying technology treatment, the surface of the material is porous, and the specific surface area of the material is increased, so that more active sites are provided for gas-sensitive reaction, and the gas-sensitive performance of the material is improved.
Drawings
The accompanying drawings, which are included to provide a further understanding of the application, illustrate and explain the application and are not to be construed as limiting the application. In the drawings:
FIG. 1 shows the single/few layer Ti as in example 1 3 C 2 T x (a) Sea urchin-like Fe 2 O 3 (b-e) and Ti 3 C 2 T x -Fe 2 O 3 Scanning electron microscope image of composite material (f).
FIG. 2 is a graph of the gas-sensitive response values for different samples for 100ppm ammonia at different operating temperatures.
FIG. 3 is a diagram of Ti prepared in example 1 3 C 2 T x -Fe 2 O 3 Is a scanning electron microscope image of (1).
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Example 1
Preparation of a gas sensor:
s1, preparing a single-layer/few-layer MXene sol material: 1g of sodium fluoride powder (NaF is more than or equal to 99 percent) is taken and dissolved in 10mL of hydrochloric acid (HCl) with the concentration of 9mol/L, and the mixture is stirred for 30 minutes at room temperature; 1g of Ti was dissolved in ice 3 AlC 2 Slowly adding MAX material powder into the solution, sealing the solution, transferring the solution into 35 ℃ oil bath, and continuously stirring for 24 hours; repeatedly centrifuging and washing the obtained precipitate with deionized water at 3500r/min for 10 times, wherein each centrifuging time is 5min; the black precipitate (multilayer Ti 3 C 2 T x ) Ultrasonic treating in deionized water for 20min (500W), centrifuging at 3500rpm for 30min to obtain single/few Ti layers 3 C 2 T x And (3) sol.
S2, preparing PDDA modified sea urchin-shaped Fe 2 O 3 : 0.020mol FeCl was taken 3 ·6H 2 O and 0.80mmol (NH) 4 ) 2 SO 4 Respectively adding into 40ml deionized water under magnetic stirring (350 rpm) to form uniform mixed solution, transferring the yellow mixed solution into stainless steel polytetrafluoroethylene high-pressure reaction kettle, water-bathing at 120deg.C for 12 hr, naturally cooling to room temperature after reaction, washing the obtained solution with deionized water and absolute ethanol for several times to obtain clean yellow precipitate, drying in 80 deg.C oven for 8 hr, sampling, and sintering the obtained sample at 600deg.C under air atmosphere for 2 hr to obtain red powder sample (sea urchin-like Fe) 2 O 3 ) Dispersing the red powdery sample into 500mL polydiallyl dimethyl ammonium chloride, performing ultrasonic treatment for 5h (power is 180W), filtering, washing with water, and drying in a vacuum drying oven at 80deg.C for 16h to obtain PDDA modified sea urchin-like Fe 2 O 3 Is denoted as Fe 2 O 3 -PDDA。
S3, porous MXene-Fe 2 O 3 Is prepared from the following steps: taking 1g of prepared Fe 2 O 3 -PDDA, drying in a vacuum oven at 70 ℃ for 12h; adding single-layer/few-layer Ti under stirring 3 C 2 T x 10mL of sol liquid; centrifuging the mixed solution, removing supernatant, adding 10mL deionized water into the precipitate, and stirring under argon atmosphere for 1 minAnd 0h. The suspension was poured into a polytetrafluoroethylene mold until the solution in the mold had been totally frozen into ice. The frozen sample is placed in a vacuum freeze dryer for bidirectional freeze drying (the conditions are 0.1Pa and the drying at the temperature of minus 60 ℃ for 48 hours) to obtain porous MXene-Fe 2 O 3 Is denoted as Ti 3 C 2 T x -Fe 2 O 3 。
S4, ti is mixed with 3 C 2 T x -Fe 2 O 3 Mixing with 50% ethanol, grinding for 15min to 560nm, printing on ceramic plate of platinized electrode, sintering in tubular furnace at 550deg.C under Ar protective atmosphere for 2 hr to obtain gas sensor.
FIG. 3 is a diagram of Ti prepared in example 1 3 C 2 T x -Fe 2 O 3 As can be seen from FIG. 3, the surface of the material is porous after being processed by the bidirectional freeze drying technology, so that the specific surface area of the material is increased.
Example 2
Preparation of a gas sensor:
s1, the difference from example 1 is that Ta is selected as the MAX material 2 AlC, single layer/few layer Ta is prepared 2 CT x And (3) sol.
S2, the same as in the embodiment 1.
S3, the single layer/few layer Ta 2 CT x Sol 5mL and 2g Fe 2 O 3 PDDA is mixed, the supernatant is removed after centrifugation of the mixed solution, 10mL of deionized water is added to the precipitate and vigorously stirred under argon for 12h. The suspension was poured into a polytetrafluoroethylene mold until the solution in the mold had been totally frozen into ice. The frozen sample is placed in a vacuum freeze dryer for bidirectional freeze drying (the condition is 0.2Pa and the drying is carried out for 72 hours at the temperature of minus 80 ℃) to obtain porous MXene-Fe 2 O 3 Composite material, denoted Ta 2 CT x -Fe 2 O 3 。
S4, ta 2 CT x -Fe 2 O 3 Mixing with 50% ethanol, grinding for 15min to obtain granulePrinting on a ceramic plate of a platinized electrode with a diameter of 560nm, placing in a tube furnace, and sintering for 2 hours under Ar protective atmosphere at 550 ℃ to obtain the gas sensor.
Example 3
Preparation of a gas sensor:
s1 is different from the embodiment 1 only in that Nb is adopted as the MAX material 3 AlC 4 Preparing single-layer/few-layer Nb 3 C 4 T x And (3) sol.
S2, the same as in the embodiment 1.
S3, single layer/few layer Nb 3 C 4 T x Sol 20mL and 3g Fe 2 O 3 PDDA is mixed, the supernatant is removed after centrifugation of the mixed solution, 10mL of deionized water is added to the precipitate and vigorously stirred under argon for 20h. The suspension was poured into a polytetrafluoroethylene mold until the solution in the mold had been totally frozen into ice. The frozen sample is placed in a vacuum freeze dryer for bidirectional freeze drying (the condition is 0.3Pa and the drying is carried out for 72 hours at the temperature of minus 80 ℃) to obtain porous MXene-Fe 2 O 3 Composite material, denoted Nb 3 C 4 T x -Fe 2 O 3 。
S4, nb is added 3 C 4 T x -Fe 2 O 3 Mixing with 50% ethanol, grinding for 15min to 560nm, printing on ceramic plate of platinized electrode, sintering in tubular furnace at 550deg.C under Ar protective atmosphere for 2 hr to obtain gas sensor.
Comparative example 1
Preparation of a gas sensor:
single/few layer Ti obtained in step S1 of example 1 3 C 2 T x Preparing the sol into the gas sensor.
Comparative example 2
Preparation of a gas sensor:
the red powdery sample obtained in step S2 of example 1 (sea urchin-like Fe 2 O 3 ) And preparing the gas sensor.
Comparative example 3
Preparation of a gas sensor:
s1 is the same as in example 1.
S2, preparing sea urchin-shaped Fe 2 O 3 : 0.020mol FeCl was taken 3 ·6H 2 O and 0.80mmol (NH) 4 ) 2 SO 4 Respectively adding the mixture into 40ml of deionized water under the action of magnetic stirring (350 rpm) to form uniform mixed solution, transferring the yellow mixed solution into a stainless steel polytetrafluoroethylene high-pressure reaction kettle, carrying out water bath at 120 ℃ for 12 hours, naturally cooling to room temperature after the reaction is finished, washing the obtained solution with deionized water and absolute ethyl alcohol for several times to obtain clean yellow precipitate, drying the clean yellow precipitate in an oven at 80 ℃ for 8 hours, sampling, and finally sintering the obtained sample at 600 ℃ for 2 hours under the air atmosphere to obtain sea urchin-shaped Fe 2 O 3 。
S3, preparing a composite material: taking 1g of prepared sea urchin-shaped Fe 2 O 3 Drying in a vacuum box at 70 ℃ for 12 hours; adding single-layer/few-layer Ti under stirring 3 C 2 T x 10mL of sol liquid; after the mixed solution was centrifuged, the supernatant was removed, and 10mL of deionized water was added to the precipitate and stirred vigorously under argon for 10 hours. The suspension was poured into a polytetrafluoroethylene mold until the solution in the mold had been totally frozen into ice. And (3) placing the frozen sample in a vacuum freeze dryer for bidirectional freeze drying (the conditions are 0.1Pa and the drying time is 48 hours at minus 60 ℃), and obtaining the composite material.
And S4, mixing the composite material in the step S3 with 50% of organic solvent ethanol by mass fraction, grinding for 15min until the particle size is 560nm, printing on a ceramic plate of a platinized electrode, placing in a tubular furnace, and sintering for 2h under the protection of Ar at 550 ℃ to obtain the gas sensor.
Comparative example 4
Preparation of a gas sensor:
s1 is the same as in example 1.
S2, the same as in the embodiment 1.
S3, compared with the embodiment 1, the method is different in that the suspension is poured into a polytetrafluoroethylene mould in the step S3, and then the composite material is obtained by drying at normal temperature (30 ℃).
And S4, mixing the composite material in the step S3 with 50% of organic solvent ethanol by mass fraction, grinding for 15min until the particle size is 560nm, printing on a ceramic plate of a platinized electrode, placing in a tubular furnace, and sintering for 2h under the protection of Ar at 550 ℃ to obtain the gas sensor.
Comparative example 5
Preparation of a gas sensor:
s1, preparing a multi-layer MXene sol material: 1g of sodium fluoride powder (NaF is more than or equal to 99 percent) is taken and dissolved in 10mL of hydrochloric acid (HCl) with the concentration of 9mol/L, and the mixture is stirred for 30 minutes at room temperature; 1g of Ti was dissolved in ice 3 AlC 2 Slowly adding MAX material powder into the solution, sealing the solution, transferring the solution into 35 ℃ oil bath, and continuously stirring for 24 hours; repeatedly centrifuging and washing the obtained precipitate with deionized water at 3500r/min for 5min for 10 times to obtain multilayer Ti 3 C 2 T x And (3) sol.
S2, the same as in the embodiment 1.
S3, preparing a composite material: taking 1g of prepared Fe 2 O 3 -PDDA, drying in a vacuum oven at 70 ℃ for 12h; adding multiple layers of Ti under stirring 3 C 2 T x 10mL of sol liquid; after the mixed solution was centrifuged, the supernatant was removed, and 10mL of deionized water was added to the precipitate and stirred vigorously under argon for 10 hours. The suspension was poured into a polytetrafluoroethylene mold until the solution in the mold had been totally frozen into ice. And (3) placing the frozen sample in a vacuum freeze dryer for bidirectional freeze drying (the conditions are 0.1Pa and the drying time is 48 hours at minus 60 ℃), and obtaining the composite material.
And S4, mixing the composite material in the step S3 with 50% of organic solvent ethanol by mass fraction, grinding for 15min until the particle size is 560nm, printing on a ceramic plate of a platinized electrode, placing in a tubular furnace, and sintering for 2h under the protection of Ar at 550 ℃ to obtain the gas sensor.
Test examples
Gas-sensitive performance test:
the gas sensors obtained in examples 1 to 3 and comparative examples 1 to 5 were used to test the gas sensitivity performance of the prepared gas sensors at 100℃in a gas sensitive test apparatus (SD 101, huachuang Ruike Science and Technology Wuhan Co.Ltd), using a dynamic test method, the specific operations were as follows:
1. the sensor is connected in the gas-sensitive test equipment, and the equipment is filled with air to be stable, namely the resistance value (Rair) of the device in the air.
2. And (3) introducing ammonia gas with the concentration of 100ppm into the test bottle of the equipment until the response signal reaches stability, namely the resistance value (R) of the device in the ammonia gas with the concentration of 100 ppm.
3. And re-introducing air into the equipment until the equipment reaches stability, and completing a response recovery process by the device. The ratio of the resistance difference delta R of the device in air and ethanol to the resistance value in air (delta R/Rair is 100%) is the response value of the device to ammonia with the concentration.
The same procedure as described above was used to obtain the response values of the gas sensors obtained in examples 1 to 3 and comparative examples 1 to 5 to 100ppm ammonia gas, and the ratio of the difference between the resistance values of the sensors in examples 1 to 3 and comparative examples 1 to 6 in 100ppm ammonia gas and the resistance values in air to the air resistance value was shown in Table 1 at 100 ℃.
TABLE 1
As can be seen from the comparison of the data of example 1 and comparative examples 1 to 3 in Table 1, ti-based MXene and Fe 2 O 3 The composition has the best gas-sensitive response effect; as can be seen from the data of example 1 and comparative example 4, the invention adopts bidirectional freeze drying to effectively increase the specific surface area and stable structure of the material, and remarkably enhance the gas-sensitive response value; as can be seen from the data of example 1 and comparative example 5, the single/few layers of the gas sensor prepared from the single/few layers of the MXene sol material and the multi-layer MXene sol material have higher gas sensitivityA response value. Example 1 and comparative examples 1-2, it can be seen that the single/few layer MXene sol material of the present invention was compared with PDDA modified sea urchin-like Fe 2 O 3 Can produce synergistic effect and promote gas-sensitive response effect, and can be seen from the comparison of the data of the example 1 and the comparative example 3 that the sea urchin-shaped Fe is modified by PDDA 2 O 3 The gas-sensitive response effect of the product obtained by compounding with the single-layer/few-layer MXene sol material is obviously higher than that of sea urchin-shaped Fe which is not modified by PDDA 2 O 3 The material and the single/few layer MXene sol material are prepared into a product, which is due to sea urchin-shaped Fe modified by unmodified PDDA 2 O 3 The material and the single/few layer MXene sol material cannot be composited together resulting in no composite efficacy therebetween.
FIG. 1 shows the single/few layer Ti prepared in example 1 3 C 2 T x Material (a), sea urchin-like Fe 2 O 3 (b-e) and Ti 3 C 2 T x -Fe 2 O 3 And (f) scanning electron microscope pictures of the composite material. From FIG. 1, sea urchin-like Fe can be seen 2 O 3 Distributed in less layer of Ti 3 C 2 T x The contact area between the surface and the interlayer is increased, and a porous composite structure is formed.
FIG. 2 shows the structure of example 1 (Ti 3 C 2 T x -Fe 2 O 3 ) Comparative example 1 (Ti 3 C 2 T x ) And comparative example 2 (Fe 2 O 3 ) The prepared sensor has gas-sensitive response value for 100ppm ammonia at different working temperatures. As can be seen from FIG. 2, sea urchin-like Fe 2 O 3 With Ti 3 C 2 T x Can obviously improve the gas-sensitive response of the material, and is respectively pure Fe 2 O 3 And Ti is 3 C 2 T x 2 times and 3.2 times the gas-sensitive properties.
In the present specification, each embodiment is described in a progressive manner, and each embodiment is mainly described in a different point from other embodiments, and identical and similar parts between the embodiments are all enough to refer to each other.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. Porous MXene-Fe 2 O 3 The preparation method of the composite material is characterized by comprising the following steps:
single-layer/few-layer MXene sol material and sea urchin-shaped Fe modified by PDDA (polymer dispersed architecture) 2 O 3 Mixing and then vigorously stirring under the protection of inert atmosphere to obtain a mixed solution;
the mixed solution is subjected to bidirectional freeze drying under vacuum condition, and the porous MXene-Fe is obtained 2 O 3 A composite material;
the single-layer/few-layer MXene sol material is Nb 2 CT x 、Nb 3 C 4 T x 、Ta 2 CT x 、Ta 4 C 3 T x 、Ti 2 CT x And Ti is 3 C 2 T x At least one of them.
2. The method according to claim 1, wherein the sea urchin-like Fe 2 O 3 The preparation method of (2) comprises the following steps:
FeCl is added 3 ·6H 2 O and (NH) 4 ) 2 SO 4 Dissolving in water, mixing and stirring, reacting under a hydrothermal condition, and collecting a solid product;
cleaning and drying the solid product, and sintering under the air condition to obtain sea urchin-shaped Fe 2 O 3 A material.
3. The method of claim 2, wherein the feci 3 ·6H 2 O、(NH 4 ) 2 SO 4 And water in the molar/volume ratio of 0.015-0.030 mol to 0.76-0.86 mmol to 30-50 mL; the reaction temperature under the hydrothermal condition is 120-160 ℃ and the reaction time is 12-36 h; the sintering temperature is 600-800 ℃ and the sintering time is 2-4 h.
4. The method of claim 1, wherein the PDDA modification comprises: the sea urchin-like Fe 2 O 3 Dispersing into polydiallyl dimethyl ammonium chloride, ultrasonically filtering, washing, and drying to obtain the PDDA modified sea urchin-shaped Fe 2 O 3 。
5. The method according to claim 1, wherein the single/few layer MXene sol material is mixed with PDDA modified sea urchin-like Fe 2 O 3 The volume mass ratio of (1) to (3) g is 5-30 mL; the temperature of the bidirectional freeze drying is-60 to-80 ℃ and the time is 40 to 72 hours.
6. A porous MXene-Fe prepared by the method of any one of claims 1 to 5 2 O 3 A composite material.
7. A porous MXene-Fe as claimed in claim 6 2 O 3 The application of the composite material in the preparation of the gas-sensitive sensing material.
8. A gas sensor, characterized in that the raw material comprises the porous MXene-Fe as defined in claim 6 2 O 3 A composite material.
9. A method of manufacturing a gas sensor according to claim 8, comprising the steps of:
the porous MXene-Fe is treated by an organic solvent as a grinding medium 2 O 3 Grinding the composite material, printing the ground composite material on a ceramic sheet of a platinized electrode, and sintering the composite material for 2 to 4 hours under the protection of argon atmosphere to obtain the platinum-plated electrodeA gas sensor;
the sintering temperature is 350-550 ℃.
10. A gas sensor in NH according to claim 8 3 Application in the detection of gases.
CN202311516864.4A 2023-11-15 2023-11-15 Porous MXene-Fe 2 O 3 Preparation method and application of composite material Pending CN117550648A (en)

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