CN108470647B - A kind of supercapacitor combination electrode material and preparation method thereof - Google Patents
A kind of supercapacitor combination electrode material and preparation method thereof Download PDFInfo
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- CN108470647B CN108470647B CN201810430890.8A CN201810430890A CN108470647B CN 108470647 B CN108470647 B CN 108470647B CN 201810430890 A CN201810430890 A CN 201810430890A CN 108470647 B CN108470647 B CN 108470647B
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Abstract
The invention discloses a kind of supercapacitor PEDOT:PSS@g-C3N4Combination electrode material and preparation method thereof.Blocky g-C is made the following steps are included: (1) calcines melamine in Muffle furnace in it3N4；(2) by blocky g-C3N4Mixture is washed till neutrality with deionized water, milk-white coloured suspension is obtained after obtained solid dialysed overnight by the chemical oxidation in potassium bichromate and the concentrated sulfuric acid after reaction, centrifugation, takes supernatant to get g-C is arrived3N4Nanometer sheet solution；(3) PEDOT:PSS is added to g-C3N4In nanometer sheet solution, after adding, ultrasonic disperse is uniform, obtains supercapacitor combination electrode material.The present invention has good capacitive property and cyclical stability using electrode composite material obtained by component both in the composite material respectively synergistic effect of property, is the ideal electrode material of supercapacitor.
Description
Technical field
The invention belongs to electrode material for super capacitor technical field, in particular to a kind of supercapacitor PEDOT:
PSS@g-C3N4Combination electrode material and preparation method thereof.
Background technique
Electrochemical capacitor is referred to as supercapacitor, since it is with high capacity, high power density, long-life and cost
A kind of low advantage, it is considered to be the equipment of great potential of next-generation energy storage.The selection of electrode material is that influence is super
The various materials as electrode of super capacitor have been studied so far in the key factor of capacitor chemical property
Material, carbon material (active carbon, carbon nanotube, graphene etc.) are widely used in electric double layer due to its bigger serface and electric conductivity
In the electrode material of capacitor, but the low energy densities of carbon material supercapacitor limit its practical application.Graphite-phase C3N4
(g-C3N4) be graphene derivative, have similar structure with graphene.It is the atom of a kind of two-dimensional graphitic carbon and nitrogen
Layer, due to its higher chemical stability, low cost, environment friendly, in the energy storage such as photocatalysis and fuel cell, super capacitor
System is applied.Since the aspect ratio of two-dimensional material can show biggish specific surface area, which can provide excellent electricity
Lotus storage performance.And compared with traditional carbon material, g-C3N4In nitrogen can improve the electron donor characteristic of material, improve electricity
The wetability of Xie Zhizhong material, further increases capacitive property.
In the past few years, conducting polymer (PANi, PPy, PTh and its derivative) is due to its good electric conductivity, change
It learns and has been widely used in electrochemical capacitor with the features such as thermal stability, low material cost and quick charge/discharge capability
The electrode material of device.Poly- (3,4- second dioxy thiophene): poly- (styrene sulfonic acid) (PEDOT:PSS) is used as one of polythiophene material,
Since the subject and object material being used as in supercapacitor hybrid system in different solvents can be distributed to quickly to mention
High conductivity and performance.
Summary of the invention
For overcome the deficiencies in the prior art, the purpose of the present invention is to provide a kind of poly- (3, the 4- Asias of supercapacitor
Ethyl dioxy thiophene): poly- (styrene sulfonic acid)@graphite phase carbon nitride combination electrode material and preparation method thereof.System of the invention
Preparation Method is simple, at low cost；Electrode composite material obtained has good capacitive property and stability.
Technical solution of the present invention is specifically described as follows.
The present invention provides a kind of supercapacitor PEDOT:PSS@g-C3N4The preparation method of combination electrode material, including
Following steps:
(1) melamine is calcined in Muffle furnace and blocky g-C is made3N4；
(2) by blocky g-C3N4The chemical oxidation in potassium bichromate and the concentrated sulfuric acid will be mixed with deionized water after reaction
It closes object and is washed till neutrality, obtain milk-white coloured suspension after gained mixture dialysed overnight, be centrifuged, take supernatant to get solid content is arrived
The about g-C of 1.2-1.6mg/ml3N4Nanometer sheet solution；
(3) according to PEDOT:PSS and g-C3N4The mass ratio of solid content in nanometer sheet solution is 1:1~1:7, will
PEDOT:PSS is added to the g-C of step (2)3N4In nanometer sheet solution, after adding, ultrasonic disperse is uniform, at a temperature of 75-85 DEG C
It is dry, obtain supercapacitor PEDOT:PSS@g-C3N4Combination electrode material.
In the present invention, in step (1), calcination procedure is as follows: after being warming up to 540-560 DEG C with 3-6 DEG C per minute of rate,
Heat preservation 3-5 hours.
In the present invention, in step (2), blocky g-C3N4, potassium bichromate and the concentrated sulfuric acid feed ratio be 1g:(9-11) g:
(40-60)ml。
In the present invention, in step (2), centrifugation rate 2800-3200rpm.
In the present invention, in step (3), the ultrasonic disperse time is 30-90min.
In the present invention, in step (3), PEDOT:PSS and g-C3N4The mass ratio of solid content in nanometer sheet solution is 1:1
~1:5.
The present invention also provides supercapacitor PEDOT:PSS@g-C made from a kind of above-mentioned preparation method3N4Compound electric
Pole material.
Compared with prior art, the invention has the following advantages:
(1) the PEDOT:PSS@g-C that the present invention is prepared using direct mixing method3N4Composite process is simple, does not need multiple
Miscellaneous equipment and low in cost, it is only necessary to the electrode of super capacitor material that the shorter time can obtain stable structure, have excellent performance
Material.
(2) PEDOT:PSS@g-C prepared by the present invention3N4Composite material has good electrochemical stability and enhancing
Capacitive property is the ideal electrode material of supercapacitor.
Detailed description of the invention
Fig. 1 is g-C prepared by the present invention in embodiment 33N4(a) and PEDOT:PSS@g-C3N4(b) transmission electron microscopy
Mirror TEM figure.
Fig. 2 is PEDOT:PSS@g-C prepared by the present invention in embodiment 33N4The Nai Kui of the electrochemical impedance spectroscopy of composite material
Si Tetu.
Fig. 3 is PEDOT:PSS@g-C prepared by the present invention in embodiment 33N4Composite material following under different scanning rates
Ring voltammogram.
Fig. 4 is PEDOT:PSS@g-C prepared by the present invention in embodiment 33N4Perseverance of the composite material under different current densities
Flow charging and discharging curve figure.
Fig. 5 is PEDOT:PSS@g-C prepared by the present invention in embodiment 33N4The stable circulation performance curve of composite material
Figure.
Specific embodiment
Combined with specific embodiments below and attached drawing, further the present invention is illustrated.
In embodiment, its marque of PEDOT:PSS used is CLEVIOSTMPH 1000, solid content 1-1.3% glue
Spend 15-50mPas.
Embodiment 1
Melamine calcines preparation g-C in Muffle furnace3N4, calcination procedure is as follows: calcination procedure is as follows: with 5 DEG C per minute
Rate be warming up to 560 DEG C after, keep the temperature 3 hours.10g potassium bichromate and the 50mL concentrated sulfuric acid are mixed into solution in flask
Become brown, 1g g-C is added3N4It is sufficiently stirred at room temperature 2 hours.Then mixture is washed till neutrality with deionized water, institute
Obtain faint yellow solid dialysed overnight in bag filter.Finally, milk-white coloured suspension obtained is centrifuged with 3000rpm to remove not
The g-C of dispersion3N4, take supernatant to get the g-C for being about 1.5mg/ml to solid content3N4Nanometer sheet solution.By solution solid content
Mass ratio 1:1 PEDOT:PSS is added drop-wise to g-C3N4Ultrasound 1 hour in solution, obtains PEDOT:PSS g- after 80 DEG C of dryings
C3N4(1:1) composite material.Electrochemical property test is carried out to it, the charge transfer resistance (Rct) of the composite material is 1.10,
And there is lower equivalent series impedance and excellent diffusion.Cyclic voltammetry curve is in class rectangle, there is weaker oxidation
Reduction peak shows the rapid electric charge transmission capacity of both electric double layer capacitance and fake capacitance.It can be calculated by charging and discharging curve,
When current density is 1A g-1When, which goes out 114F g-1Specific capacitance value, have excellent chemical property.
Embodiment 2
Melamine calcines preparation g-C in Muffle furnace3N4, calcination procedure is as follows: calcination procedure is as follows: with 4 DEG C per minute
Rate be warming up to 550 DEG C after, keep the temperature 4 hours.
11g potassium bichromate and the 40mL concentrated sulfuric acid are mixed into solution in flask and become brown, 1g g-C is added3N4
It is sufficiently stirred at room temperature 2 hours.Then mixture is washed till neutrality with deionized water, gained faint yellow solid is in bag filter
Dialysed overnight.Finally, milk-white coloured suspension obtained is centrifuged with 3000rpm to remove undispersed g-C3N4, supernatant is taken,
Obtain the g-C that solid content is about 1.4mg/ml3N4Nanometer sheet solution.By the mass ratio 1:3 of solution solid content by PEDOT:PSS
It is added drop-wise to g-C3N4Ultrasound 1 hour in solution, obtains PEDOT:PSS g-C after 80 DEG C of dryings3N4(1:3) composite material.To it
Electrochemical property test is carried out, the charge transfer resistance (Rct) of the composite material is 0.98, and has lower equivalent series electricity
Resistance value and excellent diffusion.Cyclic voltammetry curve is in class rectangle, has weaker redox peaks, shows electric double layer capacitance
With the rapid electric charge transmission capacity of both fake capacitances.It can be calculated by charging and discharging curve, when current density is 1A g-1When, it should
Composite material exhibits go out 159F g-1Specific capacitance value, have excellent chemical property.
Embodiment 3
Melamine calcines preparation g-C in Muffle furnace3N4, calcination procedure is as follows: calcination procedure is as follows: with 5 DEG C per minute
Rate be warming up to 540 DEG C after, keep the temperature 5 hours.
9g potassium bichromate and the 50mL concentrated sulfuric acid are mixed into solution in flask and become brown, 1g g-C is added3N4?
It is sufficiently stirred at room temperature 2 hours.Then mixture is washed till neutrality with deionized water, gained faint yellow solid is saturating in bag filter
Analysis is overnight.Finally, milk-white coloured suspension obtained is centrifuged with 3100rpm to remove undispersed g-C3N4, supernatant is taken, i.e.,
Obtain the g-C that solid content is about 1.6mg/ml3N4Nanometer sheet solution.By the mass ratio 1:5 of solid content in solution by PEDOT:PSS
It is added drop-wise to g-C3N4Ultrasound 1 hour in solution, obtains PEDOT:PSS g-C after 80 DEG C of dryings3N4(1:5) composite material.To it
Electrochemical property test is carried out, the charge transfer resistance (Rct) of the composite material is 0.79, and has lower equivalent series electricity
Resistance value and excellent diffusion.It is specific as Figure 1-Figure 5.Fig. 1 is g-C in embodiment 33N4(a) and PEDOT:PSS@g-
C3N4(b) transmission electron microscope TEM figure.g-C3N4It is intended to the structure of stratiform and multilayer accumulation, PEDOT:PSS is in g-C3N4
It can be observed that apparent contrast in figure after surface aggregate, it means that water-soluble PEDOT:PSS can be in g-C3N4Lamella
In be stabilized.Fig. 2 is PEDOT:PSS@g-C in embodiment 33N4Composite material is in 1M H2SO4Electrification in electrolyte solution
Learn the nyquist diagram of impedance spectrum (EIS).The resistance of the material is smaller and curve is almost vertical line, shows absolute ideal
Capacitance behavior.Fig. 3 is PEDOT:PSS@g-C in embodiment 33N4Composite material is in 2-100mV s-1Sweep speed under follow
Ring voltammogram.Cyclic curve is in class rectangle, has weaker redox peaks, this is a typical system, shows electric double layer
The rapid electric charge transmission capacity of both capacitor and fake capacitance collaboration.Fig. 4 is PEDOT:PSS@g-C in embodiment 33N4Composite material
In 1-10A g-1Current density under constant current charge-discharge curve graph.Charging curve show it is fabulous linear and with discharged
Discharge curve near symmetrical in journey.Discharge curve is started without apparent IR drop, shows the internal series-connection electricity of the capacitor
Hinder smaller and preferable energy-storage property.In 1A g-1Current density under, the PEDOT:PSS@g-C that is prepared in example 33N4It is compound
The specific capacitance value of material is 277F g-1.Fig. 5 is PEDOT:PSS@g-C in embodiment 33N4Composite material is in 10A g-1Electric current
The cycle performance curve measured under density.The PEDOT:PSS@g-C after 5000 charge-discharge tests3N4Show lesser capacitor
Consumption, capacitor retention rate are 94.2%, show it with good cyclical stability.
Embodiment 4
Melamine calcines preparation g-C in Muffle furnace3N4, calcination procedure is as follows: calcination procedure is as follows: with 6 DEG C per minute
Rate be warming up to 550 DEG C after, keep the temperature 4 hours.
10g potassium bichromate and the 60mL concentrated sulfuric acid are mixed into solution in flask and become brown, 1g g-C is added3N4
It is sufficiently stirred at room temperature 2 hours.Then mixture is washed till neutrality with deionized water, gained faint yellow solid is in bag filter
Dialysed overnight.Finally, milk-white coloured suspension obtained is centrifuged with 2900rpm to remove undispersed g-C3N4, supernatant is taken,
Obtain the g-C that solid content is about 1.5mg/ml3N4Nanometer sheet solution.By the mass ratio 1:7 of solid content in solution by PEDOT:
PSS is added drop-wise to g-C3N4Ultrasound 1 hour in solution, obtains PEDOT:PSS g-C after 80 DEG C of dryings3N4(1:7) composite material.
Electrochemical property test is carried out to it, the charge transfer resistance (Rct) of the composite material is 1.02, and has lower equivalent string
Join resistance value and excellent diffusion.Cyclic voltammetry curve is in class rectangle, has weaker redox peaks, shows electric double layer
The rapid electric charge transmission capacity of both capacitor and fake capacitance.It can be calculated by charging and discharging curve, when current density is 1A g-1
When, which goes out 143F g-1Specific capacitance value, have excellent chemical property.Above embodiments are only to this
The technical solution of invention is described in further detail, and the present invention is not limited to the above embodiment.Technology people in the field
Member reads made to any change of the invention or adjustment etc. after above content, belongs to application protection model of the invention
It encloses.
Claims (7)
1. a kind of preparation method of supercapacitor combination electrode material, which comprises the following steps:
(1) melamine is calcined in Muffle furnace and blocky g-C is made3N4；
(2) by blocky g-C3N4The chemical oxidation in potassium bichromate and the concentrated sulfuric acid, after reaction, with deionized water by mixture
It is washed till neutrality, obtains milk-white coloured suspension after gained mixture dialysed overnight, is centrifuged, takes the supernatant to be to get to solid content
The g-C of 1.2-1.6mg/ml3N4Nanometer sheet solution；
(3) according to PEDOT:PSS and g-C3N4The mass ratio of solid content in nanometer sheet solution is 1:1~1:7, by PEDOT:PSS
It is added to the g-C of step (2)3N4In nanometer sheet solution, after adding, ultrasonic disperse is uniform, dry at a temperature of 75-85 DEG C, obtains
Supercapacitor PEDOT:PSS@g-C3N4Combination electrode material.
2. preparation method according to claim 1, which is characterized in that in step (1), calcination procedure is as follows: with per minute
After 3-6 DEG C of rate is warming up to 540-560 DEG C, 3-5 hours are kept the temperature.
3. preparation method according to claim 1, which is characterized in that in step (2), blocky g-C3N4, potassium bichromate and dense
The feed ratio of sulfuric acid is 1g:(9-11) g:(40-60) ml.
4. preparation method according to claim 1, which is characterized in that in step (2), centrifugation rate 2800-
3200rpm。
5. preparation method according to claim 1, which is characterized in that in step (3), the ultrasonic disperse time is 30-
90min。
6. preparation method according to claim 1, which is characterized in that in step (3), PEDOT:PSS and g-C3N4Nanometer sheet
The mass ratio of solid content in solution is 1:2~1:5.
7. supercapacitor combination electrode material made from a kind of preparation method according to claim 1.
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| CN103254200A (en) * | 2013-05-22 | 2013-08-21 | 福州大学 | C3N4 nanosheet with molecular-scale thickness as well as preparation method and application thereof |
| CN103361698A (en) * | 2013-07-15 | 2013-10-23 | 清华大学深圳研究生院 | Method for preparing supercapacitor electrode material by means of coelectrodeposition |
| CN103680996A (en) * | 2013-12-18 | 2014-03-26 | 江苏大学 | Polypyrrole/graphite type carbon nitride nanocomposite and preparation method thereof |
| CN105374562A (en) * | 2015-11-03 | 2016-03-02 | 渤海大学 | Graphite phase C3N4/conductive black carbon composite counter electrode preparation method |
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| CN103254200A (en) * | 2013-05-22 | 2013-08-21 | 福州大学 | C3N4 nanosheet with molecular-scale thickness as well as preparation method and application thereof |
| CN103361698A (en) * | 2013-07-15 | 2013-10-23 | 清华大学深圳研究生院 | Method for preparing supercapacitor electrode material by means of coelectrodeposition |
| CN103680996A (en) * | 2013-12-18 | 2014-03-26 | 江苏大学 | Polypyrrole/graphite type carbon nitride nanocomposite and preparation method thereof |
| CN105374562A (en) * | 2015-11-03 | 2016-03-02 | 渤海大学 | Graphite phase C3N4/conductive black carbon composite counter electrode preparation method |
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