A kind of method of disperseing double-walled carbon nano-tube by DMF and ethylene glycol combination not damaged
Technical field
The present invention relates to the method that the carbon nanotube not damaged disperses in a kind of technical field of nano material, specifically a kind of method of disperseing double-walled carbon nano-tube by DMF and ethylene glycol combination not damaged.
Background technology
As a kind of novel nano material, carbon nanotube is since being found, because its unique geometry and electronic band structure have brought excellent mechanical property, electric property, thermal property and electromagnetic performance etc., these excellent performances make carbon nanotube exist great potential application advantage, it is cotton-shaped or Powdered that the carbon nanotube of general method preparation is group in macroscopic view, be with the prerequisite of its application it to be scattered in form uniform solution in the solvent.Involve the field such as chemisorption all has broad application prospects in aerospace, precision optical machinery and function weaving, solar energy power generating, an emission, electromagnetic shielding, suction such as carbon nano-tube solution.Carbon nanotube is the one dimension tubular structure in microtexture, its diameter is at 1-40 nm, length is up to several microns or centimetre-sized, so it generally is rambling winding state and occurs, make it be difficult to be dispersed, particularly for the more excellent L/D ratio of performance larger single wall or double-walled carbon nano-tube, its more difficult being scattered in the usual vehicle.So, when dispersing Nano carbon tubes, generally in solution, add tensio-active agent or carbon nano tube surface carried out grafting luminous energy group help it to be scattered in the solvent.Aforesaid method can effectively prepare carbon nano-tube solution, but the concentration of gained solution is very limited.The shortcoming of aforesaid method is that graft surface active agent molecule or luminous energy group are difficult to remove after carbon nano tube surface, affect the proper property of carbon nanotube, particularly because the adding of tensio-active agent or luminous energy group, the performances such as its electroconductibility, heat conduction decline to a great extent, and have lost the essence of carbon nanotube conducting, heat conduction and make it lose using value.
Through the literature search of prior art is found, the research that the not damaged of carbon nanotube is disperseed also is in the exploratory stage at present.The Jie Ma of Shanghai Communications University and Zi Ping Wu etc. have delivered " Purification of single-walled carbon nNanotubes by a highly efficient and nondestructive approach " (non-invasive efficient purification of single-wall carbon nano tube) and " Journal of Power Scources " (power technology) the 195th phase in 2010 2143 pages " Preparation of dispersible double-walled carobn nanotubes and application as catalyst support in fuel cells " (double-walled carbon nano-tube of preparation high dispersive is used for the support of the catalyst of fuel cell) two literary compositions 2895 pages of " Chemistry of Materials " (chemical material) the 20th phases in 2008, in these two pieces of documents, not damaged purifying and the dispersion of carbon nanotube are suggested, they are by the method for solid state reaction and ultra-sonic dispersion, obtained the list of not damaged purifying and dispersion, double-walled carbon nano-tube solution has shown preferably performance.Yet because the method restriction, the maximum concentration of gained solution only has 0.15 mg mL
-1, thereby production cost is higher.
Summary of the invention
The present invention has developed the method that the double-walled carbon nano-tube not damaged disperses, dispersion medium by double-walled carbon nano-tube that not damaged is disperseed is optimized, then carry out ultrasonic for a long time, obtained being uniformly dispersed, considerable change do not occur in carbon nano tube surface structure and degree of graphitization, maximum concentration can reach 1.0 mg mL
-1Double-walled carbon nano-tube solution.Thereby bring great convenience for the subsequent applications of carbon nanotube; Raw material of the present invention is simple and easy to, and is with low cost, environmentally safe; In the production process without inflammable dangerous raw material; Product is easy to process, and yield is high, and equipment is simple, can semicontinuously operate, and is suitable for a large amount of productions.
The present invention relates to a kind of double-walled carbon nano-tube solution of high density, in the solution without obvious sediment and particle suspensions, solvent in the solution is by ethylene glycol and N, dinethylformamide forms, solute is comprised of less than the double-walled carbon nano-tube of 50 nm at 1-2 um, tube bank diameter in 2-10 nm, length diameter, and the complete peak of solute and the Raman spectrum ratio at defective peak are not less than 5.
The present invention is achieved by the following technical solutions, and the method by DMF and ethylene glycol combination not damaged dispersion double-walled carbon nano-tube that the present invention relates to comprises the steps:
Step 1, be analytical pure ethylene glycol and the N of 90:10-99:1 with volume ratio, dinethylformamide liquid is packed in the beaker of 50-500 mL and is put into Ultrasonic Cleaners and carry out ultra-sonic dispersion 5-30 min, ultrasonic cleaning acc power 600 W pass into recirculated water and guarantee that water temperature keeps 25 ° of C in the cleaning machine in the Ultrasonic Cleaners.
Step 2 is 0.15-1.0 mg mL with calculating concentration
-1Double-walled carbon nano-tube put into the solution that step 1 configuration mixes, the diameter of putting into double-walled carbon nano-tube is that 2-10 nm, length are that 5-20um, tube bank diameter are 50-200 nm, and the complete peak of double-walled carbon nano-tube and the Raman spectrum ratio at defective peak are 5-6.3.
Step 3, double-walled carbon nano-tube, ethylene glycol and N with gained in the step 2, the mixture of dinethylformamide is again put into the ultrasonic cleaning acc power and is carried out ultra-sonic dispersion 8-24 h, ultrasonic cleaning acc power 600 W pass into recirculated water and guarantee that water temperature keeps 25 ° of C in the cleaning machine in the Ultrasonic Cleaners.After ultra-sonic dispersion finishes, can obtain the double-walled carbon nano-tube dispersion liquid of different concns.The diameter of the double-walled carbon nano-tube double-walled carbon nano-tube after the dispersion is that 2-10 nm, length are that 1-4 um, tube bank diameter are 10-100 nm, and the complete peak of double-walled carbon nano-tube and the Raman spectrum ratio at defective peak are 4.8-6.1.
The present invention has following beneficial effect:Ethylene glycol has low surface energy (47.9 mN m
-1), along with the increase of ultrasonic time, increasing ethylene glycol liquid can be infiltrated on the double-walled carbon nano-tube interfascicular, thereby tube bank is expanded and soft, and under the effect of ultrasonic mechanical force, tube bank is stripped from or cuts short.Increase along with double-walled carbon nano-tube concentration in the solution, the double-walled carbon nano-tube interfascicular becomes finer and close, so that ethylene glycol is difficult to be infiltrated on the double-walled carbon nano-tube interfascicular again, high boiling wetting ability non-protonic solvent DMF has lower surface energy (35.2 mN m
-1), can make the hydrophilic C-H of generation in the mixing solutions and H-C-H strong, thereby so that ethylene glycol to enter to enter once again fine and close double-walled carbon nano-tube intrafascicular and further disperse this carbon nanotube.On the other hand because the high viscosity (21 mPas) of ethylene glycol but the sedimentation of the double-walled carbon nano-tube that establishment disperses, thereby can make this double-walled carbon nano-tube solution be able to Uniform Dispersion, but along with N, further adding (ethylene glycol and the N of dinethylformamide, the volume ratio of dinethylformamide is rear greater than 9), the C-N on double-walled carbon nano-tube surface is strong can be increased (this strong degree of graphitization that can greatly reduce carbon nanotube), and the surperficial degree of graphitization of double-walled carbon nano-tube begins to descend.
The present invention is simple for process, and the double-walled carbon nano-tube homogeneous solution that obtains can semi-continuously prepare.And can automatically regulate by the add-on of DMF the maximum concentration of preparation double-walled carbon nano-tube solution.Because the double-walled carbon nano-tube degree of graphitization is not suffered obvious destruction in the homodisperse solution, make the double-walled carbon nano-tube of gained keep the performances such as its intrinsic high conduction, heat conduction, and its length is cut short, and tube bank is opened, for its application in each field brings great convenience.Raw material of the present invention is simple and easy to, and is with low cost, environmentally safe; Without inflammable dangerous raw material; Product is easy to process, and yield is high, and equipment is simple, can realize semicontinuous operation, is suitable for a large amount of productions.
Embodiment
The below elaborates to embodiments of the invention: the present embodiment is implemented under take technical solution of the present invention as prerequisite, has provided detailed embodiment and process, but protection scope of the present invention is not limited to following embodiment.
Embodiment 1
Be analytical pure ethylene glycol and the N of 99:1 with volume ratio, dinethylformamide liquid is packed in the beaker of 50 mL and is put into Ultrasonic Cleaners and carry out ultra-sonic dispersion 5 min, ultrasonic cleaning acc power 600 W pass into recirculated water and guarantee that water temperature keeps 25 ° of C in the cleaning machine in the Ultrasonic Cleaners.Be 0.15 mg mL with calculating concentration
-1Double-walled carbon nano-tube put into finely dispersed ethylene glycol and N, in the mixing solutions of dinethylformamide, the diameter of putting into double-walled carbon nano-tube is that 2-10 nm, length are that 5-20 um, tube bank diameter are 50-200 nm, and the complete peak of double-walled carbon nano-tube and the Raman spectrum ratio at defective peak are 5.Double-walled carbon nano-tube, ethylene glycol and N with above-mentioned configuration, the mixture of dinethylformamide is again put into the ultrasonic cleaning acc power and is carried out ultra-sonic dispersion 8 h, ultrasonic cleaning acc power 600 W pass into recirculated water and guarantee that water temperature keeps 25 ° of C in the cleaning machine in the Ultrasonic Cleaners.After ultra-sonic dispersion finishes, can obtain the dispersion soln of double-walled carbon nano-tube.The diameter of the double-walled carbon nano-tube double-walled carbon nano-tube after the dispersion is that 2-10 nm, length are that 1-2 um, tube bank diameter are 10-100 nm, and the complete peak of double-walled carbon nano-tube and the Raman spectrum ratio at defective peak are 4.8.
Embodiment 2
Be analytical pure ethylene glycol and the N of 98:2 with volume ratio, dinethylformamide liquid is packed in the beaker of 100 mL and is put into Ultrasonic Cleaners and carry out ultra-sonic dispersion 15 min, ultrasonic cleaning acc power 600 W pass into recirculated water and guarantee that water temperature keeps 25 ° of C in the cleaning machine in the Ultrasonic Cleaners.Be 0.25 mg mL with calculating concentration
-1Double-walled carbon nano-tube put into finely dispersed ethylene glycol and N, in the mixing solutions of dinethylformamide, the diameter of putting into double-walled carbon nano-tube is that 2-10 nm, length are that 5-20 um, tube bank diameter are 50-200 nm, and the complete peak of double-walled carbon nano-tube and the Raman spectrum ratio at defective peak are 5.3.Double-walled carbon nano-tube, ethylene glycol and N with above-mentioned configuration, the mixture of dinethylformamide is again put into the ultrasonic cleaning acc power and is carried out ultra-sonic dispersion 12 h, ultrasonic cleaning acc power 600 W pass into recirculated water and guarantee that water temperature keeps 25 ° of C in the cleaning machine in the Ultrasonic Cleaners.After ultra-sonic dispersion finishes, can obtain the dispersion soln of double-walled carbon nano-tube.The diameter of the double-walled carbon nano-tube double-walled carbon nano-tube after the dispersion is that 2-10 nm, length are that 1-3 um, tube bank diameter are 10-100 nm, and the complete peak of double-walled carbon nano-tube and the Raman spectrum ratio at defective peak are 5.1.
Embodiment 3
Be analytical pure ethylene glycol and the N of 97:3 with volume ratio, dinethylformamide liquid is packed in the beaker of 200 mL and is put into Ultrasonic Cleaners and carry out ultra-sonic dispersion 30 min, ultrasonic cleaning acc power 600 W pass into recirculated water and guarantee that water temperature keeps 25 ° of C in the cleaning machine in the Ultrasonic Cleaners.Be 0.35 mg mL with calculating concentration
-1Double-walled carbon nano-tube put into finely dispersed ethylene glycol and N, in the mixing solutions of dinethylformamide, the diameter of putting into double-walled carbon nano-tube is that 2-10 nm, length are that 5-20 um, tube bank diameter are 50-200 nm, and the complete peak of double-walled carbon nano-tube and the Raman spectrum ratio at defective peak are 6.3.Double-walled carbon nano-tube, ethylene glycol and N with above-mentioned configuration, the mixture of dinethylformamide is again put into the ultrasonic cleaning acc power and is carried out ultra-sonic dispersion 24 h, ultrasonic cleaning acc power 600 W pass into recirculated water and guarantee that water temperature keeps 25 ° of C in the cleaning machine in the Ultrasonic Cleaners.After ultra-sonic dispersion finishes, can obtain the dispersion soln of double-walled carbon nano-tube.The diameter of the double-walled carbon nano-tube double-walled carbon nano-tube after the dispersion is that 2-10 nm, length are that 1-2 um, tube bank diameter are 10-100 nm, and the complete peak of double-walled carbon nano-tube and the Raman spectrum ratio at defective peak are 6.1.
Embodiment 4
Be analytical pure ethylene glycol and the N of 96:4 with volume ratio, dinethylformamide liquid is packed in the beaker of 500 mL and is put into Ultrasonic Cleaners and carry out ultra-sonic dispersion 30 min, ultrasonic cleaning acc power 600 W pass into recirculated water and guarantee that water temperature keeps 25 ° of C in the cleaning machine in the Ultrasonic Cleaners.Be 0.45 mg mL with calculating concentration
-1Double-walled carbon nano-tube put into finely dispersed ethylene glycol and N, in the mixing solutions of dinethylformamide, the diameter of putting into double-walled carbon nano-tube is that 2-10 nm, length are that 5-20 um, tube bank diameter are 50-200 nm, and the complete peak of double-walled carbon nano-tube and the Raman spectrum ratio at defective peak are 5.8.Double-walled carbon nano-tube, ethylene glycol and N with above-mentioned configuration, the mixture of dinethylformamide is again put into the ultrasonic cleaning acc power and is carried out ultra-sonic dispersion 24 h, ultrasonic cleaning acc power 600 W pass into recirculated water and guarantee that water temperature keeps 25 ° of C in the cleaning machine in the Ultrasonic Cleaners.After ultra-sonic dispersion finishes, can obtain the dispersion soln of double-walled carbon nano-tube.The diameter of the double-walled carbon nano-tube double-walled carbon nano-tube after the dispersion is that 2-10 nm, length are that 1-3 um, tube bank diameter are 10-100 nm, and the complete peak of double-walled carbon nano-tube and the Raman spectrum ratio at defective peak are 5.6.
Embodiment 5
Be analytical pure ethylene glycol and the N of 95:5 with volume ratio, dinethylformamide liquid is packed in the beaker of 300 mL and is put into Ultrasonic Cleaners and carry out ultra-sonic dispersion 20 min, ultrasonic cleaning acc power 600 W pass into recirculated water and guarantee that water temperature keeps 25 ° of C in the cleaning machine in the Ultrasonic Cleaners.Be 0.60 mg mL with calculating concentration
-1Double-walled carbon nano-tube put into finely dispersed ethylene glycol and N, in the mixing solutions of dinethylformamide, the diameter of putting into double-walled carbon nano-tube is that 2-10 nm, length are that 5-20 um, tube bank diameter are 50-200 nm, and the complete peak of double-walled carbon nano-tube and the Raman spectrum ratio at defective peak are 5.5.Double-walled carbon nano-tube, ethylene glycol and N with above-mentioned configuration, the mixture of dinethylformamide is again put into the ultrasonic cleaning acc power and is carried out ultra-sonic dispersion 20 h, ultrasonic cleaning acc power 600 W pass into recirculated water and guarantee that water temperature keeps 25 ° of C in the cleaning machine in the Ultrasonic Cleaners.After ultra-sonic dispersion finishes, can obtain the dispersion soln of double-walled carbon nano-tube.The diameter of the double-walled carbon nano-tube double-walled carbon nano-tube after the dispersion is that 2-10 nm, length are that 1-2 um, tube bank diameter are 10-100 nm, and the complete peak of double-walled carbon nano-tube and the Raman spectrum ratio at defective peak are 5.3.
Embodiment 6
Be analytical pure ethylene glycol and the N of 93:7 with volume ratio, dinethylformamide liquid is packed in the beaker of 500 mL and is put into Ultrasonic Cleaners and carry out ultra-sonic dispersion 10 min, ultrasonic cleaning acc power 600 W pass into recirculated water and guarantee that water temperature keeps 25 ° of C in the cleaning machine in the Ultrasonic Cleaners.Be 0.80 mg mL with calculating concentration
-1Double-walled carbon nano-tube put into finely dispersed ethylene glycol and N, in the mixing solutions of dinethylformamide, the diameter of putting into double-walled carbon nano-tube is that 2-10 nm, length are that 5-20 um, tube bank diameter are 50-200 nm, and the complete peak of double-walled carbon nano-tube and the Raman spectrum ratio at defective peak are 6.3.Double-walled carbon nano-tube, ethylene glycol and N with above-mentioned configuration, the mixture of dinethylformamide is again put into the ultrasonic cleaning acc power and is carried out ultra-sonic dispersion 20 h, ultrasonic cleaning acc power 600 W pass into recirculated water and guarantee that water temperature keeps 25 ° of C in the cleaning machine in the Ultrasonic Cleaners.After ultra-sonic dispersion finishes, can obtain the dispersion soln of double-walled carbon nano-tube.The diameter of the double-walled carbon nano-tube double-walled carbon nano-tube after the dispersion is that 2-10 nm, length are that 1-2 um, tube bank diameter are 10-100 nm, and the complete peak of double-walled carbon nano-tube and the Raman spectrum ratio at defective peak are 5.8.
Embodiment 7
Be analytical pure ethylene glycol and the N of 90:10 with volume ratio, dinethylformamide liquid is packed in the beaker of 500 mL and is put into Ultrasonic Cleaners and carry out ultra-sonic dispersion 18 min, ultrasonic cleaning acc power 600 W pass into recirculated water and guarantee that water temperature keeps 25 ° of C in the cleaning machine in the Ultrasonic Cleaners.Be 1.0 mg mL with calculating concentration
-1Double-walled carbon nano-tube put into finely dispersed ethylene glycol and N, in the mixing solutions of dinethylformamide, the diameter of putting into double-walled carbon nano-tube is that 2-10 nm, length are that 5-20 um, tube bank diameter are 50-200 nm, and the complete peak of double-walled carbon nano-tube and the Raman spectrum ratio at defective peak are 6.3.Double-walled carbon nano-tube, ethylene glycol and N with above-mentioned configuration, the mixture of dinethylformamide is again put into the ultrasonic cleaning acc power and is carried out ultra-sonic dispersion 24 h, ultrasonic cleaning acc power 600 W pass into recirculated water and guarantee that water temperature keeps 25 ° of C in the cleaning machine in the Ultrasonic Cleaners.After ultra-sonic dispersion finishes, can obtain the dispersion soln of double-walled carbon nano-tube.The diameter of the double-walled carbon nano-tube double-walled carbon nano-tube after the dispersion is that 2-10 nm, length are that 1-2 um, tube bank diameter are 10-80 nm, and the complete peak of double-walled carbon nano-tube and the Raman spectrum ratio at defective peak are 5.2.