CN106024425B - A kind of preparation method of CNT/cotton compound - Google Patents
A kind of preparation method of CNT/cotton compound Download PDFInfo
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- CN106024425B CN106024425B CN201610527679.9A CN201610527679A CN106024425B CN 106024425 B CN106024425 B CN 106024425B CN 201610527679 A CN201610527679 A CN 201610527679A CN 106024425 B CN106024425 B CN 106024425B
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Abstract
The present invention relates to a kind of preparation method of CNT/cotton compound, and the multi-walled carbon nanotube for being acidified post-modification is mixed with dodecyl sodium sulfate SDBS, ultrasonic disperse, obtains carbon nano tube dispersion liquid；Bafta and carbon nano tube dispersion liquid are handled, taken out after being cooled to room temperature, is cleaned, room temperature is dried, and is produced.Compound light weight of the present invention, flexibility are good, available for flexible electrode material field；More importantly the composite can be advantageous to improve overall electric conductivity and specific capacitance as the base material of other electrode materials；Preparation method is simple and easy, avoided in the past repeatedly the complicated technology method of " dipping drying ", and had the characteristics of time saving province effect, beneficial to batch production.
Description
Technical field
The invention belongs to the preparation field of flexible electrode material, the preparation of more particularly to a kind of CNT/cotton compound
Method.
Background technology
With the development of society, people strengthen the demand of the energy year by year, the discovery of new energy and develop into when business
It is anxious.Ultracapacitor has been to be concerned by more and more people as energy storage original paper, and it is widely used in mobile phone, computer, electronic
The field such as automobile and medical treatment.In ultracapacitor, electrode material be its performance play key, common electrode material master
There are carbon material, metal oxide and the class of conducting polymer three.Wherein, CNT is one be widely studied in carbon material
Class.
CNT was found that it is that a kind of length is micron, a diameter of in 1991 by Japanese Scientists SumioIijima
Nano level typical monodimension nanometer material, its specific surface area is big, density is small, electrical conductivity is high and stability is good.In electric capacity
In the preparation field of device, CNT is common used material, and its hollow structure and big specific surface area carry for the storage of electric charge
Good place is supplied, therefore CNT is usually used in the preparation of electrode material.
Research currently for carbon nanotube electrode material focuses primarily upon tabletting and film etc., strong in order to improve its
Degree, is combined it with non-woven fabrics about researcher.The A of patent CN 102704351 have invented a kind of system of carbon nano-tube non-woven fabrics
Preparation Method, material surface surfactant-free residual, can improve dispersiveness of the resin matrix to carbon nano-tube non-woven fabrics.
But the electrode material that CNT is combined with bafta is less studied, reason is CNT to fabric
Affinity is poor.Once there is pertinent literature report, bafta is carried out Low Temperature Plasma Treating by researcher, to increase on bafta
Reactive group, then CNT/bafta compound is prepared by supersound process, but on the compound of this method preparation, carbon is received
The adsorbance of mitron is not high.Also there is researcher to be modified CNT, to improve its hydrophily, then use for several times repeatedly
The method of " dipping-drying " prepares CNT/cotton compound, so as to obtain electric conductivity.But this method operating process is cumbersome, effect
Rate is low, is unfavorable for producing in batches.
It is therefore desirable to invent a kind of simple to operate and efficiency high method to prepare CNT/cotton compound, not only
The development softly changed beneficial to electrode material, it is more beneficial for the preparation using the compound as the electrode material of the higher performance of base material.
This patent solves emphatically how rapid batch prepares CNT/cotton compound, it is intended to improves efficiency, simplifies technique
The content of the invention
The technical problems to be solved by the invention are to provide a kind of preparation method of CNT/cotton compound, the present invention
Electrode material is prepared with the method that bafta is combined using CNT, possesses light weight and the advantages such as flexibility is good；Meanwhile
Using this method, be advantageous to CNT and fully contacted with the disposable of bafta, it is easy to operate, it is time saving and energy saving, avoid with
Toward repeated operation, beneficial to batch production.
A kind of preparation method of CNT/cotton compound of the present invention, including：
(1) multi-walled carbon nanotube MWCNT, concentrated nitric acid are mixed, after reflow treatment, is cooled to room temperature, filtering, washing, incites somebody to action
Gained black powder, which is placed in baking oven, dries, and obtains acidified modified multi-walled carbon nanotube, preserves stand-by；
(2) multi-walled carbon nanotube for being acidified post-modification is mixed with dodecyl sodium sulfate SDBS, ultrasonic disperse, obtains carbon
Nanotube dispersion liquid；
(3) by bafta and carbon nano tube dispersion liquid (bath raio 1:50) it is placed in constant temperature oscillation water-bath and is handled,
Take out, clean, room temperature is dried, and produces CNT/cotton compound after being cooled to room temperature.
Multi-walled carbon nanotube, the ratio of concentrated nitric acid are 0.5-3g in the step (1)：200-400mL.
The mass fraction of concentrated nitric acid is 65% in the step (1), and concentrated nitric acid used is not added with deionized water.
Reflow treatment is the reflow treatment 5-12h in heat collecting type constant-temperature heating magnetic stirring apparatus in the step (1).
Washing is in neutrality to filtrate to be washed with deionized in the step (1)；Drying temperature is 50-65 DEG C.
The multi-walled carbon nanotube of acidifying post-modification, dodecyl sodium sulfate SDBS mass ratio are 1 in the step (2):
1。
The ultrasonic disperse time is 0.5-2h in the step (2).
Handled specially in water-bath in the step (3)：20-25 DEG C starts to warm up, heating rate be 1-3 DEG C/
Min, 10-40min is incubated after being raised to 95-100 DEG C.
It is to be down to room temperature with 1-3 DEG C/min that room temperature is cooled in the step (3).
CNT/application of the cotton compound as flexible electrode in the step (3).
The present invention carries out sour modification to CNT first, improves its hydrophily and dispersiveness, then prepares carbon and receive
Mitron dispersion liquid, and bafta and carbon nano tube dispersion liquid are placed in constant temperature oscillation water-bath simultaneously, so as to prepare carbon nanometer
Pipe/cotton compound.The compound light weight, flexibility are good, available for flexible electrode material field；The more importantly composite wood
Material can be advantageous to improve overall electric conductivity and specific capacitance as the base material of other electrode materials.Because the preparation method is simple
It is easy, the complicated technology method of " dipping-drying " was avoided in the past repeatedly, there is the characteristics of time saving province effect, beneficial to batch production.
Beneficial effect
The present invention prepares electrode material using CNT with the method that bafta is combined, and possesses light weight and flexibility
The advantage such as good；
Meanwhile using this method, be advantageous to CNT and fully contacted with the disposable of bafta, it is easy to operate, it is time saving
It is laborsaving, conventional repeated operation is avoided, beneficial to batch production.
Brief description of the drawings
Fig. 1 is preparation flow schematic diagram of the present invention；
Fig. 2 is the cyclic voltammetry curve test chart of long multi-wall CNT (L-MWCNT)/cotton compound；
Fig. 3 is the adhesion test chart of L-MWCNT/ cotton compounds；
Fig. 4 is the cyclic voltammetry curve test chart of short MWCNTs (S-MWCNT)/cotton compound；
Fig. 5 is the adhesion test chart of S-MWCNT/ cotton compounds；
Fig. 6 is that " adhesive tape method of testing " adhesion tests rating scale.
Embodiment
With reference to specific embodiment, the present invention is expanded on further.It should be understood that these embodiments are merely to illustrate the present invention
Rather than limitation the scope of the present invention.In addition, it is to be understood that after the content of the invention lectured has been read, people in the art
Member can make various changes or modifications to the present invention, and these equivalent form of values equally fall within the application appended claims and limited
Scope.
Embodiment 1
A kind of processing method of L-MWCNT/ cottons compound, is concretely comprised the following steps：
(1) the acidified modified processing of CNT：
A. 1.5g L-MWCNT and 300mL concentrated nitric acids are added in 500mL three-necked flask, in heat collecting type heated at constant temperature magnetic
In power agitator, reflow treatment 10h；
B. after handling, room temperature is cooled to, is filtered, is washed with deionized water to filtrate in neutrality, gained black powder is placed in
In baking oven, 60 DEG C drying, obtain it is acidified modified after L-MWCNT, preserve it is stand-by.
(2) preparation of carbon nano-tube solution：
L-MWCNT and SDBS after will be acidified modified is with 1:1 mass ratio is placed in ultrasonic disperse 1h in distilled water, prepares carbon
Nanotube dispersion liquid.
(3) preparation of CNT/cotton compound
A. by bafta and the carbon nano-tube solution (bath raio 1 prepared:50) it is placed in constant temperature oscillation water-bath and carries out
Processing, process conditions are 20 DEG C and started to warm up that programming rate is 2 DEG C/min, is incubated 30min after being raised to 100 DEG C, then with 2 DEG C/
Min cools to 20 DEG C；
B. CNT/cotton compound is taken out, is cleaned, room temperature is dried.
Embodiment 2
A kind of processing method of S-MWCNT/ cottons compound, is concretely comprised the following steps：
A. 1.5g S-MWCNT and 300mL concentrated nitric acids are added in 500mL three-necked flask, in heat collecting type heated at constant temperature magnetic
In power agitator, reflow treatment 10h；
B. after handling, room temperature is cooled to, is filtered, is washed with deionized to filtrate in neutrality, gained black powder is put
In baking oven, 60 DEG C drying, obtain it is acidified modified after S-MWCNT, preserve it is stand-by.
(2) preparation of carbon nano-tube solution：
S-MWCNT and SDBS after will be acidified modified is with 1:1 mass ratio is placed in ultrasonic disperse 1h in distilled water, prepares carbon
Nanotube dispersion liquid.
(3) preparation of CNT/cotton compound
A. by bafta and the carbon nano-tube solution (bath raio 1 prepared:50) it is placed in constant temperature oscillation water-bath and carries out
Processing, process conditions are 20 DEG C and started to warm up that programming rate is 2 DEG C/min, is incubated 30min after being raised to 100 DEG C, then with 2 DEG C/
Min cools to 20 DEG C；
B. CNT/cotton compound is taken out, is cleaned, room temperature is dried.
In above-described embodiment, CNT is purchased from Nanometer Port Co., Ltd., Shenzhen, and performance parameter is as shown in table 1.Other
Agents useful for same is the pure rank of analysis, in use without further purifying.Use the double probe tests of electrical measurement four of RTS-9 types
Instrument (Guangzhou Xi Mei Science and Technology Ltd.s) tests sheet resistance；Use the electrochemical workstation of Shanghai Chen Hua Instrument Ltd.
CHI660E carries out the test of cyclic voltammetry curve, and wherein working electrode is CNT/cotton compound, is platinum electrode to electrode,
Reference electrode is calomel electrode, and sweep speed is respectively 0.001V/s, 0.005V/s, 0.01V/s and 0.1V/s, electrolyte solution
For 4mol/L NaCl solutions, and specific capacitance is calculated according to formula (1).
Wherein, C represents the size of specific capacitance, and unit is Fg-1；I represents electric current, and unit is A；V represents voltage, and unit is V；
F represents the sweep speed of voltage, and unit is mVs–1；M represents the quality of active material, and unit is g.
The performance parameter of the CNT of table 1
| Model | External diameter (nm) | Length (μm) | Purity (%) | Gray scale (wt%) | Specific surface area (m2/g) |
| L-MWNT-2040 | 20-40 | 5-15 | >97 | <3 | 80~140 |
| S-MWNT-2040 | 20-40 | <2 | >97 | <3 | 70~150 |
CNT prepared by embodiment 1/cotton compound is tested, as a result as follows：
Test one：Sheet resistance
By test, the average sheet resistance of L-MWCNT/ cotton compounds is 3.3K Ω/sq, electric conductivity and conducting polymer species
Seemingly.
Test two：Cyclic voltammetry curve (CV)
The cyclic voltammetry curve test chart that Fig. 2 is carried out by L-MWCNT/ cottons compound under different scanning rates.Can be with
Find out, with the increase of sweep speed, the area of cyclic voltammetry curve becomes larger, but the CV figures of L-MWCNT/ cotton compounds are in
Existing parallelogram, illustrates that the material meets the charge storage mechanisms of electric double layer capacitance.It is computed, is 1mV/s in sweep speed
When, specific capacitance 5.87F/g.
Test three：Adhesion is tested
Fig. 3 is the adhesion test chart of L-MWCNT/ cotton compounds, " the adhesive tape test commonly used using conductive fabric industry
Method " is tested.Test result shows that the adhesion of the compound can reach 3-4 levels.
Silver-plated bafta prepared by embodiment 2 is tested, as a result as follows：
Test one：Sheet resistance
By test, the average sheet resistance of S-MWCNT/ cotton compounds is 9.32K Ω/sq, electric conductivity and conducting polymer
It is similar.
Test two：Cyclic voltammetry curve (CV)
Fig. 4 is the cyclic voltammetry curve test chart that S-MWCNT/ cottons compound is carried out under different scanning rates.It can see
Go out, with the increase of sweep speed, the area of cyclic voltammetry curve becomes larger；Meanwhile the CV figures of S-MWCNT/ cotton compounds
Parallelogram is presented, illustrates the charge storage mechanisms of the Material cladding electric double layer capacitance.It is computed, is 1mV/ in sweep speed
During s, specific capacitance 5.44F/g.
Test three：Adhesion is tested
Fig. 5 is the adhesion test chart of S-MWCNT/ cotton compounds, " the adhesive tape test commonly used using conductive fabric industry
Method " is tested.Test result shows that the adhesion of the compound can reach 3-4 levels.
Claims (9)
1. a kind of preparation method of CNT/cotton compound, including：
(1) multi-walled carbon nanotube MWCNT, concentrated nitric acid are mixed, after reflow treatment, is cooled to room temperature, filtering, washing, drying, obtains
To acidified modified multi-walled carbon nanotube；
(2) multi-walled carbon nanotube for being acidified post-modification is mixed with dodecyl sodium sulfate SDBS, ultrasonic disperse, obtains carbon nanometer
Pipe dispersion liquid；
(3) bafta and carbon nano tube dispersion liquid are handled, handled specially：20-25 DEG C starts to warm up, heating speed
Rate is 1-3 DEG C/min, is incubated 10-40min after being raised to 95-100 DEG C, is taken out after being cooled to room temperature, is cleaned, room temperature is dried, and is produced
CNT/cotton compound.
A kind of 2. preparation method of CNT/cotton compound according to claim 1, it is characterised in that：The step
(1) multi-walled carbon nanotube, the ratio of concentrated nitric acid are 0.5-3g in：200-400mL.
A kind of 3. preparation method of CNT/cotton compound according to claim 1, it is characterised in that：The step
(1) mass fraction of concentrated nitric acid is 65% in, and concentrated nitric acid used is not added with deionized water.
A kind of 4. preparation method of CNT/cotton compound according to claim 1, it is characterised in that：The step
(1) reflow treatment is the reflow treatment 5-12h in heat collecting type constant-temperature heating magnetic stirring apparatus in.
A kind of 5. preparation method of CNT/cotton compound according to claim 1, it is characterised in that：The step
(1) washing is in neutrality to filtrate to be washed with deionized in；Drying temperature is 50-65 DEG C.
A kind of 6. preparation method of CNT/cotton compound according to claim 1, it is characterised in that：The step
(2) multi-walled carbon nanotube of acidifying post-modification, dodecyl sodium sulfate SDBS mass ratio are 1 in:1.
A kind of 7. preparation method of CNT/cotton compound according to claim 1, it is characterised in that：The step
(2) the ultrasonic disperse time is 0.5-2h in.
A kind of 8. preparation method of CNT/cotton compound according to claim 1, it is characterised in that：The step
(3) it is to be down to room temperature with 1-3 DEG C/min that room temperature is cooled in.
A kind of 9. preparation method of CNT/cotton compound according to claim 1, it is characterised in that：The step
(3) CNT/application of the cotton compound as flexible electrode in.
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| CN106783226B (en) * | 2016-12-09 | 2019-02-01 | 东华大学 | A kind of preparation method of carbon nanotube/textile flexibility combination electrode material |
| CN106876155A (en) * | 2017-02-23 | 2017-06-20 | 东华大学 | A kind of preparation method of the conductive bafta based on CNT |
| CN106946551A (en) * | 2017-03-10 | 2017-07-14 | 江南大学 | A kind of graphene/carbon nano-tube strengthens the preparation method of alumina ceramic coating |
| CN106971865B (en) * | 2017-04-28 | 2019-01-15 | 东华大学 | A kind of Polymerization of Polyaniline/carbon Nanotube with high specific capacitance/cotton fabric composite and flexible electrode and its preparation and application |
| CN107170585A (en) * | 2017-05-19 | 2017-09-15 | 东华大学 | The modified by silver Polymerization of Polyaniline/carbon Nanotube of a kind of low contact resistance/bafta composite and flexible electrode and preparation method thereof |
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| CN105470003A (en) * | 2016-01-12 | 2016-04-06 | 东华大学 | Preparation method of three-dimensional carbon nano tube/textile fiber stretchable electrode material |
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| CN104485234A (en) * | 2014-12-26 | 2015-04-01 | 浙江理工大学 | Method for preparing flexible super capacitor based on textile fibers and electrodeposited polypyrrole |
| CN104505267A (en) * | 2014-12-26 | 2015-04-08 | 浙江理工大学 | Production method of planar flexible supercapacitor |
| CN105470003A (en) * | 2016-01-12 | 2016-04-06 | 东华大学 | Preparation method of three-dimensional carbon nano tube/textile fiber stretchable electrode material |
| CN105679555A (en) * | 2016-01-12 | 2016-06-15 | 东华大学 | Preparation method for three-dimensional aminated carbon nanotube array/stretchable textile fiber electrode material |
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