Polyimide aerogel based on carbon quantum dots and preparation method thereof

Abstract

The invention relates to a preparation method of polyimide aerogel based on carbon quantum dots. The method comprises the following steps: adding the carbon quantum dots prepared by a hydrothermal method into polyimide wet gel, freeze-drying, and heating in a tubular furnace at high temperature; the polyimide aerogel based on the carbon quantum dots has a large specific surface area, the specific surface area is 304-368 m < 2 > / g, the pore volume is 1.5-2.0 m < 2 > / g, the pore diameter is 18.8-20.0 nm, and the morphology is of a three-dimensional network structure; and the prepared polyimide aerogel has good photocatalytic efficiency which is 10% higher than that of pure polyimide aerogel, and a new direction is provided for photocatalytic materials.

Description

technical field

[0001] The invention relates to a polyimide airgel based on carbon quantum dots and a preparation method thereof, belonging to the technical field of materials. Background technique

[0002] In the 21st century, environmental issues and energy crises are two severe challenges facing mankind. In recent years, photocatalytic degradation has been widely concerned due to its ability to efficiently decompose pollutants and its non-polluting properties. Therefore, the preparation of new and efficient photocatalysts has become the key to the field of photocatalysis. Among many catalysts, polyimide (PI) with unique structure has attracted more and more attention from scientists. PI is called "gold polymer material", which is a kind of aromatic heterocyclic polymer with imide group (imide ring) in the main chain. PI is used in a wide range of fields and has shown outstanding performance in every application field.

[0003] As a new type of photocatalyst, PI has out...

Examples

Embodiment 1

[0058] A polyimide airgel based on carbon quantum dots is specifically prepared by the following method:

[0059] (1) Preparation of carbon quantum dots

[0060] Add 0.5 g of sucrose to 30 ml of water, stir for 30 min, transfer to a 50 ml reaction kettle, keep at 200°C for 5 h, cool, centrifuge, dialyze, and dry.

[0061] (2) Preparation of polyimide airgel based on carbon quantum dots

[0062] ① Preparation of polyimide wet gel based on carbon quantum dots: disperse 0.033g of carbon quantum dots in NMP80ml, add 2.5g ODA, 4.0gBPDA, after completely dissolved, stir for 5 minutes, add 10ml of 0.060gBTC dissolved in NMP, after stirring evenly, transfer to grinding tool, gel.

[0063] ② Aging of polyimide wet gel based on carbon quantum dots: wait for it to gel and age at room temperature for 1 day. Soak the aged gel in ethanol for solvent replacement (the replacement time is about 1 week, during which time the ethanol is replaced on average once a day).

[0064] ③ Preparation...

Embodiment 2

[0067] A polyimide airgel based on carbon quantum dots is specifically prepared by the following method:

[0068] (1) Preparation of carbon quantum dots

[0069] Add 0.75g of chitosan to 30ml of 2% glacial acetic acid, stir for 30min, transfer to a 50ml reaction kettle, cool at 180°C for 5h, centrifuge, dialyze, and dry.

[0070] (2) Preparation of polyimide airgel based on carbon quantum dots

[0071] ① Preparation of polyimide wet gel based on carbon quantum dots: Disperse 0.05g of carbon quantum dots in NMP60ml, add 2.0g ODA, 3.0g BPDA, after completely dissolved, stir for 5 minutes, add 10ml to dissolve 0.035gBTC NMP, stirred evenly, transferred to the mold, gel.

[0072] ② Aging of polyimide wet gel based on carbon quantum dots: wait for it to gel and age at room temperature for 1 day. Soak the aged gel in ethanol for solvent replacement (the replacement time is about 1 week, during which time the ethanol is replaced on average once a day).

[0073] ③ Preparation of p...

Embodiment 3

[0076] A polyimide airgel based on carbon quantum dots is specifically prepared by the following method:

[0077] (1) Preparation of carbon quantum dots

[0078] Chitosan 1.5g was added to 35ml 2% glacial acetic acid, stirred for 30min, transferred to a 50ml reactor, cooled at 160°C for 5h, centrifuged, dialyzed, and dried.

[0079] (2) Preparation of polyimide airgel based on carbon quantum dots

[0080] ① Preparation of polyimide wet gel based on carbon quantum dots: Disperse 0.24g of carbon quantum dots in NMP60ml, add 3.5g ODA, 4.5g BPDA, after completely dissolved, stir for 5 minutes, add 10ml to dissolve 0.08gBTC NMP, stirred evenly, transferred to the mold, gel.

[0081] ② Aging of polyimide wet gel based on carbon quantum dots: wait for it to gel and age at room temperature for 1 day. Soak the aged gel in ethanol for solvent replacement (the replacement time is about 1 week, during which time the ethanol is replaced on average once a day).

[0082] ③ Preparation of...

technical field

[0001] The invention relates to a polyimide airgel based on carbon quantum dots and a preparation method thereof, belonging to the technical field of materials. Background technique

[0002] In the 21st century, environmental issues and energy crises are two severe challenges facing mankind. In recent years, photocatalytic degradation has been widely concerned due to its ability to efficiently decompose pollutants and its non-polluting properties. Therefore, the preparation of new and efficient photocatalysts has become the key to the field of photocatalysis. Among many catalysts, polyimide (PI) with unique structure has attracted more and more attention from scientists. PI is called "gold polymer material", which is a kind of aromatic heterocyclic polymer with imide group (imide ring) in the main chain. PI is used in a wide range of fields and has shown outstanding performance in every application field.

[0003] As a new type of photocatalyst, PI has out...

Examples

Embodiment 1

[0058] A polyimide airgel based on carbon quantum dots is specifically prepared by the following method:

[0059] (1) Preparation of carbon quantum dots

[0060] Add 0.5 g of sucrose to 30 ml of water, stir for 30 min, transfer to a 50 ml reaction kettle, keep at 200°C for 5 h, cool, centrifuge, dialyze, and dry.

[0061] (2) Preparation of polyimide airgel based on carbon quantum dots

[0062] ① Preparation of polyimide wet gel based on carbon quantum dots: disperse 0.033g of carbon quantum dots in NMP80ml, add 2.5g ODA, 4.0gBPDA, after completely dissolved, stir for 5 minutes, add 10ml of 0.060gBTC dissolved in NMP, after stirring evenly, transfer to grinding tool, gel.

[0063] ② Aging of polyimide wet gel based on carbon quantum dots: wait for it to gel and age at room temperature for 1 day. Soak the aged gel in ethanol for solvent replacement (the replacement time is about 1 week, during which time the ethanol is replaced on average once a day).

[0064] ③ Preparation...

Embodiment 2

[0067] A polyimide airgel based on carbon quantum dots is specifically prepared by the following method:

[0068] (1) Preparation of carbon quantum dots

[0069] Add 0.75g of chitosan to 30ml of 2% glacial acetic acid, stir for 30min, transfer to a 50ml reaction kettle, cool at 180°C for 5h, centrifuge, dialyze, and dry.

[0070] (2) Preparation of polyimide airgel based on carbon quantum dots

[0071] ① Preparation of polyimide wet gel based on carbon quantum dots: Disperse 0.05g of carbon quantum dots in NMP60ml, add 2.0g ODA, 3.0g BPDA, after completely dissolved, stir for 5 minutes, add 10ml to dissolve 0.035gBTC NMP, stirred evenly, transferred to the mold, gel.

[0072] ② Aging of polyimide wet gel based on carbon quantum dots: wait for it to gel and age at room temperature for 1 day. Soak the aged gel in ethanol for solvent replacement (the replacement time is about 1 week, during which time the ethanol is replaced on average once a day).

[0073] ③ Preparation of p...

Embodiment 3

[0076] A polyimide airgel based on carbon quantum dots is specifically prepared by the following method:

[0077] (1) Preparation of carbon quantum dots

[0078] Chitosan 1.5g was added to 35ml 2% glacial acetic acid, stirred for 30min, transferred to a 50ml reactor, cooled at 160°C for 5h, centrifuged, dialyzed, and dried.

[0079] (2) Preparation of polyimide airgel based on carbon quantum dots

[0080] ① Preparation of polyimide wet gel based on carbon quantum dots: Disperse 0.24g of carbon quantum dots in NMP60ml, add 3.5g ODA, 4.5g BPDA, after completely dissolved, stir for 5 minutes, add 10ml to dissolve 0.08gBTC NMP, stirred evenly, transferred to the mold, gel.

[0081] ② Aging of polyimide wet gel based on carbon quantum dots: wait for it to gel and age at room temperature for 1 day. Soak the aged gel in ethanol for solvent replacement (the replacement time is about 1 week, during which time the ethanol is replaced on average once a day).

[0082] ③ Preparation of...

Images