A kind of g-C3N4The preparation method of surface photovoltage signal enhancing
Technical field
The present invention relates to chemical material preparation field, especially field of photocatalytic material, specially a kind of g-C3N4Surface light
The preparation method of voltage signal enhancing.
Background technique
With the development of the social economy, the problem of environmental pollution got worse has threatened the existence of the mankind.Meanwhile closely
The consumption of the resources such as coal, petroleum also brings immeasurable loss to the mankind over year, and there is an urgent need for a kind of sustainable developments for this
New technology.
It has been found that Photocatalitic Technique of Semiconductor has good potential application in protection environment and solar energy conversion aspect
Value, because its reaction condition is mild, low energy consumption, secondary pollution is few and has wide range of applications and has obtained extensive research.Photocatalysis
Agent (photocatalyst) can directly utilize sunlight as light source, preparation process also compares since itself is nontoxic and pollution-free
Simply, have many advantages, such as again while curbing environmental pollution for producing clean energy resource, for solve environmental pollution this all one's life
The problem of criticality is of great importance, so visible light photocatalysis technology is concerned.Efficient visible-light photocatalysis material should
Have the characteristics that low-energy zone, high-quantum efficiency, high stability, easily recycling, large specific surface area, easily recycling.
Carbonitride is a kind of very promising covalent compound, wherein class graphite phase carbon nitride (g-C3N4) it is at room temperature
Most stable of phase has properties such as nontoxic and visible light-responded (2.7 eV of semiconductor band gap), has it very in catalytic field
Have broad application prospects.g-C3N4With its photocatalytic activity is high, stability is good, cost of material is cheap, be especially free of metal this
One outstanding advantages make it a kind of novel photochemical catalyst.
It will be appreciated, however, that g-C3N4The photocatalytic activity electron-hole high by its is compound to be influenced, to improve g-
C3N4Photocatalysis performance, people have carried out study on the modification to it to improve the separation effect of electron-hole.It is most of inorganization
G-C can be combined or be inserted by closing object and inorganic metal ion3N4In matrix, g-C can be effectively finely tuned3N4Structure and
Improve reactivity.The study found that by g-C3N4Modification, can expand the response range of its visible light, inhibit g-C3N4's
Compound, the raising g-C of light induced electron and hole3N4Photocatalytic activity and selectivity, improve surface property, this is to g-C3N4's
Industrial applications are significant.In terms of study on the modification, various methods, including g-C are used3N4Pattern, nonmetallic mix
Miscellaneous, metal-doped, semiconductors coupling, noble metal loading, dye sensitization and surface modification etc..Zhong Junbo etc. using infusion process and
Photoreduction met hod is prepared for SO4 2-、PO4 2-With the g-C of Ag modification3N4, the results showed that surface photovoltage significantly increases, photocatalytic activity
It improves.But there is the shortcomings that cumbersome, poor controllability in above method, be badly in need of improving g-C using easy means3N4Photoproduction
Separation of charge effect, to further increase photocatalysis performance.
In all factors for influencing photocatalytic activity, the separation effect of electron-hole plays vital effect.
After photochemical catalyst receives energy greater than the light of forbidden bandwidth, only photo-generate electron-hole efficiently separates, moves to catalyst surface
After could induce light-catalyzed reaction.It can be seen that the separation of research Photoinduced Charge discloses surface for improving photocatalysis efficiency
Light-catalyzed reaction essence has great theoretical and practical significance.The research of photogenerated charge metastatic rule is that building high-performance optical is urged
The core topic of change system.Therefore, g-C is improved3N4Efficiently separating for photochemical catalyst electron-hole is urgent and necessary.
g-C3N4Photochemical catalyst photo-generate electron-hole separation effect can indicate that surface photovoltage is believed using surface photovoltage
It is number stronger, indicate that photogenerated charge separation effect is better.
Summary of the invention
The present invention is based on the above technical problems, provide a kind of g-C3N4The preparation method of surface photovoltage signal enhancing.The system
Preparation Method is easy to operate, and raw material is cheap and easily-available;The g-C prepared using this preparation method3N4, surface photovoltage signal significantly increases
By force, solid foundation is established for its practice.
The specific technical solution of the present invention is as follows:
A kind of g-C that surface photovoltage signal significantly increases3N4Preparation method refers in g-C3N4And suspension
In, ionic liquid or surfactant are added, through washing the g- for obtaining surface photovoltage signal and significantly increasing after hydro-thermal process
C3N4.Specific step is as follows:
The first step is roasted 3 hours at 550 DEG C using current semiclosed method using urea as raw material and obtains g-C3N4.Urea
For commercial product.
Second step, with the g-C prepared3N4To g-C under ionic liquid or surfactant auxiliary3N4Carry out water
Heat treatment.Specially take the g-C of 2-2.5g3N4It is dispersed in 40-60 mL deionized water, adds 0.05-0.5g ionic liquid
Or surfactant, 160-180 DEG C hydro-thermal process 0.5-2 hours, cooled to room temperature.The ionic liquid is 1- second
- 3 methylimidazolium nitrate of base, -3 methylimidazolium hydrogen sulphate salt of 1- ethyl, 1- ethyl -2,3- methylimidazole bromide, 1- ethyl -
Any one or a few mixture in 2,3- methylimidazole villaumite and 1- ethyl -2,3- methylimidazole salt compounded of iodine.It is described
Surfactant be PEG 6000 or CTAB.
Third step is used ethanol wash 1-2 times again after being washed with deionized, and powder taking-up is dispersed in alcohol, 60-80
DEG C it is drying to obtain product, test surfaces photovoltage.
A kind of g-C of surface photovoltage signal enhancing prepared by the present invention3N4, crystal phase is using X-ray powder diffraction table
Sign;Surface photovoltage test is tested on the surface photovoltaic spectroscopy that Jilin University assembles.Light source is xenon lamp, using lock-in amplifier
The signal of acquisition is amplified, sample is pressed between electro-conductive glass and oxide array on metallic copper substrate, wavelength measurement range 300-600 nm.
(1) g-C of surface photovoltage signal enhancing of the invention3N4, the preparation of catalyst only uses urine cheap and easy to get
Element, ethyl alcohol, so that catalyst of the invention has requirement cheap, suitable for mass production.
(2) g-C of surface photovoltage signal enhancing of the present invention3N4, easy to operate, the time is short, securely and reliably.
(3) g-C of the present invention under ionic liquid or surfactant auxiliary after hydrothermal treatment3N4Relatively be not added with from
The g-C of sub- liquid or surfactant auxiliary hydro-thermal process3N4, on the section 300-450 nm surface, photoelectric signal significantly increases
By force.
Detailed description of the invention
Fig. 1 is that the XRD of 1 products obtained therefrom of comparative example schemes
Fig. 2 is the surface photovoltage signal contrast figure of 1 products obtained therefrom of comparative example 1 and embodiment
Fig. 3 is the surface photovoltage signal contrast figure of 2 products obtained therefrom of comparative example 1 and embodiment
Fig. 4 is the surface photovoltage signal contrast figure of 3 products obtained therefrom of comparative example 1 and embodiment
Fig. 5 is the surface photovoltage signal contrast figure of 4 products obtained therefrom of comparative example 1 and embodiment
Fig. 6 is the surface photovoltage signal contrast figure of 5 products obtained therefrom of comparative example 1 and embodiment
Fig. 7 is the surface photovoltage signal contrast figure of 6 products obtained therefrom of comparative example 1 and embodiment
Fig. 8 is the surface photovoltage signal contrast figure of 7 products obtained therefrom of comparative example 1 and embodiment
Fig. 9 is the surface photovoltage signal contrast figure of 8 products obtained therefrom of comparative example 1 and embodiment
Figure 10 is the surface photovoltage signal contrast figure of 9 products obtained therefrom of comparative example 1 and embodiment
Specific embodiment
The present invention is further explained with comparative example combined with specific embodiments below.It will be appreciated that these embodiments are only used for
Illustrate the present invention rather than limits the scope of the invention.It should also be understood that be, after reading the content taught by the present invention,
Those skilled in the art can make various modifications or changes to the present invention, and such equivalent forms equally fall within right appended by the application
Claim limited range.
The alcohol recorded in present specification uses the standard of medicinal alcohol.
Comparative example 1
The first step is roasted 3 hours at 550 DEG C using current semiclosed method using urea as raw material and obtains g-C3N4。
Second step, to the g-C prepared3N4Carry out hydro-thermal process.Specially take 2.5 g g-C3N4It is dispersed in 60 mL
In deionized water, 180 DEG C hydro-thermal process 2 hours, cooled to room temperature.
Third step is used ethanol wash 1-2 times again after deionized water washing, and powder taking-up is dispersed in alcohol, and 80 DEG C dry
It is dry to obtain sample, test surfaces photovoltage.
Fig. 1 is that the XRD spectrogram that comparative example 1 obtains sample apparent diffraction occurs at 27.4 ° as seen from the figure
Peak, this shows that sample is class graphite phase carbon nitride.
Embodiment 1
The first step is roasted 3 hours at 550 DEG C using current semiclosed method using urea as raw material and obtains g-C3N4。
Second step, the g-C that will be prepared3N4To g-C under surfactant auxiliary3N4Carry out hydro-thermal process.Specially
Take 2.5 g g-C3N4It is dispersed in 60 mL deionized waters, 0.05g PEG6000 is then added, it is small in 180 DEG C of hydro-thermal process 2
When, cooled to room temperature.
Third step is used ethanol wash 1-2 times again after substance obtained in second step is washed with deionized, powder is taken
It is dispersed in alcohol out, 80 DEG C are dried to obtain sample, test surfaces photovoltage.
It is compared with comparative example 1, Surfactant PEG 6000 is added in embodiment 1.
Fig. 2 is that the surface photovoltage signal of 1 products obtained therefrom of comparative example 1 and embodiment compares figure.As can be seen that through second step
After Surfactant PEG 6000 assists hydro-thermal process, g-C3N4Surface photovoltage signal significantly increases.
Embodiment 2
The first step is roasted 3 hours at 550 DEG C using current semiclosed method using urea as raw material and obtains g-C3N4。
Second step, with the g-C prepared3N4To g-C under surfactant auxiliary3N4Carry out hydro-thermal process.Specially
Take 2.5 g g-C3N4Be dispersed in 40 mL deionized waters, be added 0.05g CTAB, 160 DEG C hydro-thermal process 2 hours, natural cooling
To room temperature.
Third step is used ethanol wash 1-2 times again after deionized water washing, and powder taking-up is dispersed in alcohol, and 80 DEG C dry
It is dry to obtain sample, test surfaces photovoltage.
It is compared with comparative example 1, Surfactant CTAB is added in embodiment 2, and hydrothermal temperature is 160 DEG C, and water dispersion volume is
40 mL.
Fig. 3 is that the surface photovoltage signal of 2 products obtained therefrom of comparative example 1 and embodiment compares figure.As can be seen that through second step
After Surfactant CTAB assists hydro-thermal process, g-C3N4Surface photovoltage signal significantly increases.
Embodiment 3
The first step is roasted 3 hours at 550 DEG C using current semiclosed method using urea as raw material and obtains g-C3N4。
Second step, with the g-C prepared3N4To g-C under ionic liquid auxiliary3N4Carry out hydro-thermal process.Specially take
2.0 g g-C3N4It is dispersed in 50 mL deionized waters, addition -3 methylimidazolium nitrate of 0.1g 1- ethyl, at 170 DEG C of hydro-thermals
Reason 1 hour, cooled to room temperature.
Third step is used ethanol wash 1-2 times again after deionized water washing, and powder taking-up is dispersed in alcohol, and 80 DEG C dry
It is dry to obtain sample, test surfaces photovoltage.
It is compared with comparative example 1, -3 methylimidazolium nitrate of ionic liquid 1- ethyl, hydrothermal temperature 170 is added in embodiment 3
DEG C, water dispersion volume be 50 mL, hydro-thermal process 1 hour.
Fig. 4 is the surface photovoltage signal graph of 3 products obtained therefrom of comparative example 1 and embodiment.As can be seen that through second step 1- second
Resulting catalyst surface photoelectric signal obviously sharply enhances after -3 methylimidazolium nitrate of base auxiliary hydro-thermal process.In addition,
The section 400-450nm surface photoelectric signal enhances after adding -3 methylimidazolium nitrate of 1- ethyl, this is conducive to improve visible
Photolytic activity.
Embodiment 4
The first step is roasted 3 hours at 550 DEG C using current semiclosed method using urea as raw material and obtains g-C3N4。
Second step, with the g-C prepared3N4To g-C under ionic liquid auxiliary3N4Carry out hydro-thermal process.Specially take
2.0 g g-C3N4It is dispersed in 55 mL deionized waters, -3 methylimidazolium hydrogen sulphate salt of 0.2g 1- ethyl, 175 DEG C of hydro-thermals is added
Processing 1.5 hours, cooled to room temperature, test surfaces photovoltage.
Third step is used ethanol wash 1-2 times again after deionized water washing, and powder taking-up is dispersed in alcohol, and 80 DEG C dry
It is dry to obtain sample, test surfaces photovoltage.
It is compared with comparative example 1, -3 methylimidazolium hydrogen sulphate salt of ionic liquid 1- ethyl is added in embodiment 4, and hydrothermal temperature is
175 DEG C, water dispersion volume be 55 mL, hydro-thermal process 1.5 hours.
Fig. 5 is the surface photovoltage signal graph of 4 products obtained therefrom of comparative example 1 and embodiment.As can be seen that through second step 1- second
Resulting catalyst surface photoelectric signal obviously sharply enhances after -3 methylimidazolium hydrogen sulphate salt of base auxiliary hydro-thermal process.
Embodiment 5
The first step is roasted 3 hours at 550 DEG C using current semiclosed method using urea as raw material and obtains g-C3N4。
Second step, with the g-C prepared3N4To g-C under ionic liquid auxiliary3N4Carry out hydro-thermal process.Specially take
2.0 g g-C3N4It is dispersed in 50 mL deionized waters, 0.3g 1- ethyl -2,3- methylimidazole bromide, 175 DEG C of hydro-thermals is added
Processing 2 hours, cooled to room temperature.
Third step is used ethanol wash 1-2 times again after deionized water washing, and powder taking-up is dispersed in alcohol, and 80 DEG C dry
It is dry to obtain sample, test surfaces photovoltage.
It is compared with comparative example 1, ionic liquid 1- ethyl -2,3- methylimidazole bromide is added in embodiment 5, and hydrothermal temperature is
175 DEG C, water dispersion volume be 50 mL, hydro-thermal process 2 hours.
Fig. 6 is the surface photovoltage signal graph of 5 products obtained therefrom of comparative example 1 and embodiment.As can be seen that through second step 1- second
Resulting catalyst surface photoelectric signal obviously sharply enhances after base -2,3- methylimidazole bromide auxiliary hydro-thermal process.This
Outside, g-C after addition 1- ethyl -2,3- methylimidazole bromide3N4In the section 400-500nm, surface photovoltage signal significantly increases
By force, this is conducive to improve visible light catalysis activity.
Embodiment 6
The first step is roasted 3 hours at 550 DEG C using current semiclosed method using urea as raw material and obtains g-C3N4。
Second step, with the g-C prepared3N4To g-C under ionic liquid auxiliary3N4Carry out hydro-thermal process.Specially take
2.0 g g-C3N4It is dispersed in 45 mL deionized waters, 0.5g 1- ethyl -2,3- methylimidazole villaumite, 160 DEG C of hydro-thermals is added
Processing 0.5 hour, cooled to room temperature.
Third step is used ethanol wash 1-2 times again after deionized water washing, and powder taking-up is dispersed in alcohol, and 70 DEG C dry
It is dry to obtain sample, test surfaces photovoltage.
It is compared with comparative example 1, ionic liquid 1- ethyl -2,3- methylimidazole villaumite is added in embodiment 4, and hydrothermal temperature is
160 DEG C, water dispersion volume be 45 mL, hydro-thermal process 0.5 hour.
Fig. 7 is the surface photovoltage signal graph of 6 products obtained therefrom of comparative example 1 and embodiment.As can be seen that through second step 1- second
Resulting catalyst surface photoelectric signal obviously sharply enhances after base -2,3- methylimidazole villaumite auxiliary hydro-thermal process.
Embodiment 7
The first step is roasted 3 hours at 550 DEG C using current semiclosed method using urea as raw material and obtains g-C3N4。
Second step, with the g-C prepared3N4To g-C under ionic liquid auxiliary3N4Carry out hydro-thermal process.Specially take
2.0 g g-C3N4It is dispersed in 50 mL deionized waters, 0.4g 1- ethyl -2,3- methylimidazole salt compounded of iodine, 180 DEG C of hydro-thermals is added
Processing 2 hours, cooled to room temperature.
Third step is used ethanol wash 1-2 times again after deionized water washing, and powder taking-up is dispersed in alcohol, and 60 DEG C dry
It is dry to obtain sample, test surfaces photovoltage.
It is compared with comparative example 1, ionic liquid 1- ethyl -2,3- methylimidazole villaumite is added in embodiment 7, and hydrothermal temperature is
160 DEG C, water dispersion volume be 45 mL, hydro-thermal process 0.5 hour.
Fig. 8 is the surface photovoltage signal graph of 7 products obtained therefrom of comparative example 1 and embodiment.As can be seen that through second step hydro-thermal
Resulting catalyst surface photoelectric signal obviously sharply enhances after heat treatment.
Embodiment 8
The first step is roasted 3 hours at 550 DEG C using current semiclosed method using urea as raw material and obtains g-C3N4。
Second step, with the g-C prepared3N4To g-C under surfactant auxiliary3N4Carry out hydro-thermal process.Specially
Take 2.5 g g-C3N4Be dispersed in 40 mL deionized waters, be added 0.05 g CTAB, 150 DEG C hydro-thermal process 2 hours, it is naturally cold
But to room temperature.
Third step is used ethanol wash 1-2 times again after deionized water washing, and powder taking-up is dispersed in alcohol, and 80 DEG C dry
It is dry to obtain sample, test surfaces photovoltage.
It is compared with comparative example 1, Surfactant CTAB, g-C is added in embodiment 83N 4Mass ratio with CTAB is 2.5:
0.05.Hydrothermal temperature is 150 DEG C, and water dispersion volume is 40 mL.
Fig. 9 is that the surface photovoltage signal of 8 products obtained therefrom of comparative example 1 and embodiment compares figure.As can be seen that through second step
After Surfactant CTAB assists hydro-thermal process, g-C3N4Surface photovoltage signal does not enhance.
Embodiment 9
The first step is roasted 3 hours at 550 DEG C using current semiclosed method using urea as raw material and obtains g-C3N4。
Second step, with the g-C prepared3N4To g-C under ionic liquid auxiliary3N4Carry out hydro-thermal process.Specially take
2.0 g g-C3N4It is dispersed in 55 mL deionized waters, -3 methylimidazolium hydrogen sulphate salt of 0.6 g 1- ethyl, 175 DEG C of hydro-thermals is added
Processing 1.5 hours, cooled to room temperature, test surfaces photovoltage.
Third step is used ethanol wash 1-2 times again after deionized water washing, and powder taking-up is dispersed in alcohol, and 80 DEG C dry
It is dry to obtain sample, test surfaces photovoltage.
It is compared with comparative example 1, -3 methylimidazolium hydrogen sulphate salt of ionic liquid 1- ethyl, g-C is added in embodiment 93N 4With from
The mass ratio of sub- liquid be 2.0:0.06, hydrothermal temperature be 175 DEG C, water dispersion volume be 55 mL, hydro-thermal process 1.5 hours.
Figure 10 is the surface photovoltage signal graph of 9 products obtained therefrom of comparative example 1 and embodiment.As can be seen that through second step 1-
Resulting catalyst surface photoelectric signal does not enhance after -3 methylimidazolium hydrogen sulphate salt of ethyl auxiliary hydro-thermal process.
Example described above is only the preferred embodiment of this patent, but the protection scope of this patent is not limited thereto.
It should be pointed out that for those skilled in the art, under the premise of not departing from this patent principle, specially according to this
The technical solution and its inventional idea of benefit, can also make several improvements and modifications, these improvements and modifications also should be regarded as this specially
The protection scope of benefit.