A kind of organic metal framework coats the preparation method of two-dimentional black phosphorus nanometer sheetTechnical field
The present invention relates to black phosphorus nanometer sheets, and the system of two-dimentional black phosphorus nanometer sheet is coated more particularly, to a kind of organic metal frameworkPreparation Method.
Background technique
?phosphorus belong to one of allotrope of phosphorus, be prepared early in 1914 by American scientist, synthesizeCondition is extremely harsh.With the ?phosphorus often seen, compared with white phosphorus, the thermodynamic stability of block body ?phosphorus is relatively preferable.Document report mentionsOut can be to obtain to obtain ?phosphorus nanometer sheet using the method for mechanical stripping, the distinguishing feature of ?phosphorus nanometer sheet is that its band gap can lead toThe number of plies for crossing it is adjusted, and for variation range in 0.3~2.0eV, this compensates for the deficiency of graphene band gap just.?phosphorus nanometerAnother feature of piece is its biocompatibility, and P elements are elements necessary to life movement, and ?phosphorus can be in physiology itemNatural degradation is phosphate under part.?the unique crystal structure of phosphorus, intra-face anisotropy and biocompatibility make it in electronics devicePart and biological field have a wide range of applications.
For black phosphorus compared with other two-dimensional materials, black phosphorus is poor in aqueous oxygen containing environment stability inferior, because of easy and waterIt is reacted with oxygen, generates the various oxides of phosphorus, so that it is destructurized, so that its physical and chemical performance is influenced, thus howStablize the important ring that black phosphorus is black phosphorus Materials.
Currently, researcher mainly reduces the contact of black phosphorus and oxygen and water by using the method for physics or chemistry, butThese methods more or less have its defect to exist.The method mistake of the ligand of chemical modification titanium or diazonium benzene derivative such as on black phosphorusIn complexity (Angew.Chem.Int.Ed., 2016,55,5003-5007；NatChem.2016,8,597-602.), to experiment itemPart is harsh；In addition, if using the macromolecules such as PLGA package (Nat commun., 2016,7,12967), then can exist destroy it is blackThe two-dimensional structure problem of phosphorus.
Metal-organic framework (Metal Organic Frameworks, MOFs) as novel porous material rise inThe sixties in last century.1999, American scientist O.M.Yaghi reported the MOF- with three-dimensional net structure on Nature5 synthesis and its research of hydrogen storage property, aperture and specific surface area are much larger than traditional molecular sieve, so that this kind of material obtainsThe extensive concern of researchers, opens new era of MOFs research and development.Within subsequent decades, MOFs material is rapidBecome the hot spot that material, chemistry, physical field are studied.The most important architectural characteristic of MOFs material is exactly the hole with superelevationRate (90% or more porosity), superelevation internal surface area (reach 10000m2/ g) and superelevation specific surface area and they thisThe characteristics such as lewis acid and lewis base that body has, so that MOFs material is widely used in point of the storage of gas, gasFrom fields such as, biosensor, catalysis and drug releases.
Summary of the invention
The purpose of the present invention is to provide under the premise of not destroying black phosphorus two-dimensional structure, can be improved black phosphorus in common ringA kind of organic metal framework of border stability inferior coats the preparation method of two-dimentional black phosphorus nanometer sheet.
The present invention the following steps are included:
1) two-dimentional black phosphorus nanometer sheet is prepared；
2) the black phosphorus nanometer sheet of Metal Ions Modification is prepared；
3) the black phosphorus nanometer sheet and organic ligand of Metal Ions Modification are mixed and is dispersed in N,N-dimethylformamide DMFIn, then mixed liquor is transferred to thermostatic crystallization in reaction kettle；
4) reaction kettle is cooled to room temperature, is centrifuged, washs, and obtains organic metal framework and coats two-dimentional black phosphorus nanometer sheet.
In step 1), the specific method for preparing two-dimentional black phosphorus nanometer sheet can are as follows: is removed using ultrasonic wave added liquid phaseBlack phosphorus grinds ontology black phosphorus, is redispersed in PVP solution, Probe Ultrasonic Searching；The mass concentration of the PVP solution can be0.1mg/mL；The time of the Probe Ultrasonic Searching can be 5~10h.
In step 2), the specific method of the black phosphorus nanometer sheet for preparing Metal Ions Modification can are as follows: by metal salinityIt is dispersed in dehydrated alcohol, the type of metal ion is including but not limited to Cu2+, Zn2+, Ni+, Co2+, Mn2+, Fe3+, Sn4+, Ca2+,Al3+, Ti4+, Cr3+One of Deng, the molar concentration of the metal salt can be 8~16mmol/L.
In step 3), the organic ligand is including but not limited to terephthalic acid (TPA), amination terephthalic acid (TPA), dimethylImidazoles, to one of benzenetricarboxylic acid etc.；The temperature of the thermostatic crystallization can be 135~200 DEG C, and the time of thermostatic crystallization can beA few houres were differed by several days.
In step 4), the method for the centrifuge washing is washed repeatedly using ethyl alcohol or methanol, and centrifugal speed can be6000~8000r/min.
The present invention have it is following prominent the utility model has the advantages that
1) black phosphorus of a kind of organic metal framework cladding provided by the invention, has machine frame by forming metal on black phosphorus surfaceThe method of frame, which is realized, is fixed on black phosphorus surface for metal ion, and metal ion reduces the cloud density on black phosphorus surface, andAnd the cladding of MOF reduces the contact with water and oxygen, improves the stability of black phosphorus itself.
2) due to the high porosity of organic metal framework, the organic metal framework cladding black phosphorus being prepared be can be applied toThe storage of gas detection or gas.
Detailed description of the invention
1 Wei of figure ?phosphorus, organic metal framework NH2- MIL-53 (Al) and organic metal framework NH2- MIL-53 (Al) cladding?phosphorus X-ray diffractogram.
Fig. 2 is organic metal framework NH2- MIL-53 (Al) coat ?phosphorus transmission electron microscope picture.
3 Wei of figure ?phosphorus and organic metal framework NH2- MIL-53 (Al) coat ?phosphorus the UV absorption changed over timeSpectrogram.In Fig. 3, a Wei ?phosphorus, b be organic metal framework NH2- MIL-53 (Al) coat ?phosphorus.
Fig. 4 be organic metal framework MIL-53 (Fe) coat ?phosphorus transmission electron microscope picture.
5 Wei of figure ?phosphorus, organic metal framework ZIF-8 and organic metal framework ZIF-8 cladding ?phosphorus X-ray diffractionFigure.
Fig. 6 be organic metal framework ZIF-8 coat ?phosphorus transmission electron microscope picture.
Specific embodiment
It is clearly and completely described below with reference to technical effect of the embodiment to design and generation of the invention.
Embodiment 1
The present embodiment provides a kind of organic metal framework NH2The method that-MIL-53 (Al) coats black phosphorus, including following stepIt is rapid:
(1) 60mg black phosphorus is weighed under oxygen-free environment, is ground in the PVP aqueous solution of 0.1mg/mL；Use 950W probeThe ultrasound 5h in low temperature water-bath；Supernatant is taken after taking dispersion liquid 4000rpm to be centrifuged 10min, the supernatant is with 12000rpmPrecipitating is taken after centrifugation 6min, then precipitating is dispersed in dehydrated alcohol and repeats above-mentioned centrifugation step, finally obtains two-dimentional black phosphorusNanometer sheet (is labeled as BP).
(2) it weighs a certain amount of anhydrous aluminum chloride to be dissolved in dehydrated alcohol, concentration 8mmol/L；It will be in step (1)Two-dimentional black phosphorus nanometer sheet is dispersed in again in the ethanol solution of aluminium chloride, is then stirred overnight.
(3) 15mLN will be dispersed in again after the dispersion liquid vacuum drying in step (2), in dinethylformamide DMF,The amination terephthalic acid (TPA) of 100mg is added, stirs 5h.
(4) above-mentioned solution is transferred in 45mL reaction kettle, 135 DEG C of heated at constant temperature 5h in baking oven, after being cooled to room temperature,It is centrifuged under 8000rpm revolving speed, product can be obtained for washing 3 times (labeled as BP@MIL-53 (Al)).
It takes above-mentioned prepared BP, BP@MIL-53 (Al) to be dispersed in water respectively, respectively takes 100 μ L drops on the glass sheet, veryAfter sky is dry, analyzed using X-ray diffraction spectra, as a result as shown in Figure 1.From figure 1 it will be seen that NH2-MIL-53(Al)There is the characteristic peak of black phosphorus and NH in black phosphorus after cladding2The characteristic peak of-MIL-53 (Al), as a result illustrates organic metal frameFrame has successfully coated two-dimentional black phosphorus nanometer sheet.
It takes above-mentioned prepared BP, BP@MIL-53 (Al) to be dispersed in water respectively, is added drop-wise on micro-grid copper mesh, vacuum is dryAfter dry, structure observation is carried out to it using transmission electron microscope, as a result as shown in Fig. 2, black phosphorus uniformly coated it is a thin layer ofNH2- MIL-53 (Al) so that the smooth in surface itself ?phosphorus become coarse, therefore can successfully judge organic metal frameworkSuccessfully coat.
It takes above-mentioned prepared BP, BP@MIL-53 (Al) to be dispersed in PBS buffer solution respectively, places a period of time respectively, useUltraviolet specrophotometer tests the ultra-violet absorption spectrum of solution, as a result as shown in Figure 3.Shown in Fig. 3, within 9 days time,The absorption of black phosphorus reduces rapidly, and shows black phosphorus fast degradation in PBS solution, and BP@MIL-53 (Al) is even if passing through 30 daysAfterwards, ultraviolet spectra slightly reduces, it was demonstrated that the cladding of organic metal framework is so that BP is still able to maintain preferably in PBS solutionStability.
Embodiment 2
The present embodiment provides a kind of methods of organic metal framework MIL-53 (Fe) cladding black phosphorus, comprising the following steps:
(1) 60mg black phosphorus is weighed under oxygen-free environment, is ground in the PVP aqueous solution of 0.1mg/mL；Use 950W probeThe ultrasound 5h in low temperature water-bath；Supernatant is taken after taking dispersion liquid 4000rpm to be centrifuged 10min, the supernatant is with 12000rpmPrecipitating is taken after centrifugation 6min, then precipitating is dispersed in dehydrated alcohol and repeats above-mentioned centrifugation step, finally obtains two-dimentional black phosphorusNanometer sheet (is labeled as BP).
(2) it weighs a certain amount of anhydrous zinc chloride to be dissolved in dehydrated alcohol, concentration 8mmol/L；It will be in step (1)Two-dimentional black phosphorus nanometer sheet is dispersed in again in the ethanol solution of zinc chloride, is then stirred overnight.
(3) 15mLN will be dispersed in again after the dispersion liquid vacuum drying in step (2), in dinethylformamide DMF,The terephthalic acid (TPA) of 100mg is added, stirs 5h.
(4) above-mentioned solution is transferred in 45mL reaction kettle, 135 DEG C of heated at constant temperature 15h, are cooled to room temperature in baking ovenAfterwards, it is centrifuged under 8000rpm revolving speed, product can be obtained for washing 3 times (labeled as BP@MIL-53 (Fe)).
It takes above-mentioned prepared BP, BP@MIL-53 (Fe) to be dispersed in water respectively, is added drop-wise on micro-grid copper mesh, vacuum is dryAfter dry, structure observation is carried out to it using transmission electron microscope, as a result as shown in figure 4, black phosphorus uniformly coated it is a thin layer ofBP@MIL-53 (Fe), the cladding Ye Shi get of same MIL-53 (Fe) ?the surface of phosphorus become coarse, it was demonstrated that organic metal frameworkSuccess coats.
Embodiment 3
The present embodiment provides a kind of methods of organic metal framework ZIF-8 cladding black phosphorus, comprising the following steps:
(1) 60mg black phosphorus is weighed under oxygen-free environment, is ground in the PVP aqueous solution of 0.1mg/mL；Use 950W probeThe ultrasound 5h in low temperature water-bath；Supernatant is taken after taking dispersion liquid 4000rpm to be centrifuged 10min, the supernatant is with 12000rpmPrecipitating is taken after centrifugation 6min, then precipitating is dispersed in dehydrated alcohol and repeats above-mentioned centrifugation step, finally obtains two-dimentional black phosphorusNanometer sheet (is labeled as BP).
(2) it weighs a certain amount of anhydrous zinc chloride to be dissolved in dehydrated alcohol, concentration 8mmol/L；It will be in step (1)Two-dimentional black phosphorus nanometer sheet is dispersed in again in the ethanol solution of zinc chloride, is then stirred overnight.
(3) 15mLN will be dispersed in again after the dispersion liquid vacuum drying in step (2), in dinethylformamide DMF,The methylimidazole of 100mg is added, stirs 5h.
(4) above-mentioned solution is transferred in 45mL reaction kettle, 135 DEG C of heated at constant temperature 10h, are cooled to room temperature in baking ovenAfterwards, it is centrifuged under 8000rpm revolving speed, product can be obtained for washing 3 times (labeled as BP@ZIF-8).
It takes above-mentioned prepared BP, BP@ZIF-8 to be dispersed in water respectively, respectively takes 100 μ L drops on the glass sheet, vacuum is dryIt after dry, is analyzed using X-ray diffraction spectra, as a result as shown in Figure 1.It is seen from fig 5 that the black phosphorus after ZIF-8 claddingThere is the characteristic peak of black phosphorus and the characteristic peak of ZIF-8, as a result illustrates that organic metal framework has successfully coated two dimensionBlack phosphorus nanometer sheet.
It takes above-mentioned prepared BP, BP@ZIF-8 to be dispersed in water respectively, is added drop-wise on micro-grid copper mesh, after vacuum drying,Structure observation is carried out to it using transmission electron microscope, as a result as shown in fig. 6, black phosphorus has uniformly coated a thin layer of ZIF-8, successfully prove that organic metal framework successfully coats.
Tong Guo of the present invention ?phosphorus surface modified metal ion first, it is raw in surface in situ then by organoligand coordinationLong one layer of uniform organic metal framework layer, one side Jiang Di ?phosphorus and water and oxygen contact, Ti Gao ?phosphorus stability；The high surface area and porosity that another aspect organic metal framework has are expected to open up exhibition ?phosphorus in gas detection and gas storageThe application in field.Organic metal framework Bao Fu provided by the invention ?phosphorus method, and simple process, applied widely, needleAll has good applicability to the corresponding organic metal framework of various metals ion.