阅读说明：本技术 一种尺寸可调的CsPbBr3纺锤型钙钛矿微米颗粒的制备方法 (Size-adjustable CsPbBr3Preparation method of spindle-type perovskite micron particles ) 是由 李红波 英起飞 刘向东 黄岭 于 2020-05-15 设计创作，主要内容包括：本发明公开了一种尺寸可调的CsPbBr<Sub>3</Sub>纺锤型钙钛矿微米颗粒的制备方法,制备过程中,先以5-己炔酸和10-十一碳炔酸为表面配体分别制备得到5-己炔酸CsPbBr<Sub>3</Sub>钙钛矿纳米晶体溶液和10-十一碳炔酸CsPbBr<Sub>3</Sub>钙钛矿纳米晶体溶液,再将5-己炔酸CsPbBr<Sub>3</Sub>钙钛矿纳米晶体溶液和10-十一碳炔酸CsPbBr<Sub>3</Sub>钙钛矿纳米晶体溶液分别按不同体积比混合,最后将各混合后的溶液置于紫外灯光照下反应,得到不同长宽比的CsPbBr3纺锤型钙钛矿微米颗粒。本发明制备方法简单,一次性能够制备得到具有较高发光纯度且发光寿命可调的CsPbBr3纺锤型钙钛矿微米颗粒,通过本发明方法制备得到的纺锤型钙钛矿CsPbBr<Sub>3</Sub>微米颗粒的长宽比可调控,带隙变小,发光半峰宽窄,色纯度高、发光寿命长,具有优异的光电性能。(The invention discloses a CsPbBr with adjustable size 3 The preparation method of the spindle-type perovskite micron particles comprises the steps of firstly respectively preparing 5-hexynoic acid CsPbBr by taking 5-hexynoic acid and 10-undecenoic acid as surface ligands 3 Perovskite nanocrystal solution and 10-undecenoic acid CsPbBr 3 Perovskite nanocrystal solution, adding 5-hexynoic acid CsPbBr 3 Perovskite nanocrystal solution and 10-undecenoic acid CsPbBr 3 And mixing the perovskite nano crystal solutions according to different volume ratios, and finally placing the mixed solutions under the illumination of an ultraviolet lamp for reaction to obtain CsPbBr3 spindle-type perovskite micro particles with different length-width ratios. The preparation method is simple, and the prepared product has high luminous purity and adjustable luminous lifeCsPbBr3 spindle-type perovskite micron particles, and spindle-type perovskite CsPbBr prepared by the method 3 The micron particles have adjustable length-width ratio, small band gap, narrow half-peak width of luminescence, high color purity, long luminescence life and excellent photoelectric property.)

1. Size-adjustable CsPbBr₃The preparation method of the spindle-type perovskite micron particles is characterized in that in the preparation process, 5-hexynoic acid CsPbBr is prepared by respectively taking 5-hexynoic acid and 10-undecenoic acid as surface ligands₃Perovskite nanocrystal solution and 10-undecenoic acid CsPbBr₃Perovskite nanocrystal solution, adding 5-hexynoic acid CsPbBr₃Perovskite nanocrystal solution and 10-undecenoic acid CsPbBr₃Mixing the perovskite nano crystal solutions according to different volume ratios, and finally placing the mixed solutions under the illumination of an ultraviolet lamp for reaction to obtain CsPbBr with different length-width ratios₃Spindle-type perovskite microparticles.

2. The size tunable CsPbBr of claim 1₃The preparation method of the spindle-type perovskite micron particles is characterized in that the 5-hexynoic acid CsPbBr₃Perovskite nanocrystal solution and 10-undecenoic acid CsPbBr₃The volume ratio of the perovskite nanocrystal solution is 2: 8-8: 2.

3. The size tunable CsPbBr of claim 1₃The preparation method of the spindle-type perovskite micron particles is characterized in that the reaction conditions of ultraviolet lamp illumination are as follows: simultaneously, ultraviolet lamps with the wavelengths of 254nm and 365nm are adopted for illumination for 12-36 hours.

4. The size tunable CsPbBr of claim 1₃The preparation method of the spindle-type perovskite micron particles is characterized by comprising the following steps:

(1) heating and stirring cesium salt, octadecene and oleic acid under the protection of nitrogen until the cesium salt, octadecene and oleic acid are completely dissolved to obtain a standby solution;

(2) mixing lead bromide, octadecene, oleylamine and 5-hexynoic acid, stirring at constant temperature under the protection of nitrogen until the lead bromide, octadecene, oleylamine and 5-hexynoic acid are completely dissolved, quickly injecting the standby solution obtained in the step (1) at the temperature of 140-150 ℃, cooling to room temperature after stirring, adding absolute ethyl alcohol for washing, discarding supernatant after centrifugation, dissolving precipitate in cyclohexane, centrifuging again, and collecting supernatant to obtain 5-hexynoic acid CsPbBr₃A perovskite nanocrystal solution;

(3) mixing lead bromide, octadecene, oleylamine and 10-undecaynoic acid, stirring at constant temperature under the protection of nitrogen until the lead bromide, octadecene, oleylamine and 10-undecaynoic acid are completely dissolved, quickly injecting the standby solution obtained in the step (1) at the temperature of 160-170 ℃, cooling to room temperature after stirring, adding absolute ethyl alcohol for washing, centrifuging, discarding supernate, dissolving the precipitate in cyclohexane, centrifuging again, collecting supernate, and obtaining 10-undecaynoic acid CsPbBr₃A perovskite nanocrystal solution;

(4) mixing the 5-hexynoic acid CsPbBr3 perovskite nanocrystal solution and 10-undecyynoic acid CsPbBr₃Perovskite nanocrystalsMixing the solution according to different volume ratios, and placing the mixed solutions under the illumination of a dark box type ultraviolet lamp in a constant temperature environment to perform acetylene bond coupling reaction to obtain CsPbBr with different length-width ratios₃Spindle-type perovskite microparticles.

5. The size tunable CsPbBr of claim 4₃The preparation method of the spindle-type perovskite micron particles is characterized in that the cesium salt is any one of cesium carbonate, cesium bromide or cesium acetate.

6. The size tunable CsPbBr of claim 4₃The preparation method of the spindle-type perovskite micron particles is characterized in that in the step (1), 0.2-0.3 g of cesium salt, 10-20 ml of octadecene and 0.75-1.5 ml of oleic acid are used.

7. The size tunable CsPbBr of claim 4₃The preparation method of the spindle-type perovskite micron particles is characterized in that in the step (2), 0.1-0.2 g of lead bromide, 10-20 ml of octadecene, 1-3 ml of oleylamine and 0.2-0.4 ml of 5-hexynoic acid are contained; taking 0.8-1.2 ml of the solution for later use in the step (1); the volume of the cyclohexane is 5-15 ml.

8. The size tunable CsPbBr of claim 4₃The preparation method of the spindle-type perovskite micron particles is characterized in that in the step (3), 0.1-0.2 g of lead bromide, 10-20 ml of octadecene, 1-3 ml of oleylamine and 0.03-0.06 g of 10-undecydonic acid are used; taking 0.8-1.2 ml of the solution for later use in the step (1); the volume of the cyclohexane is 5-15 ml.

9. The size tunable CsPbBr of claim 4₃The preparation method of the spindle-type perovskite micron particles is characterized in that the constant-temperature stirring temperature is 100-120 ℃.

10. The size tunable CsPbBr of claim 4₃The preparation method of the spindle-type perovskite micron particles is characterized in that in the step (4), 5-hexynoic acid CsPbBr₃Perovskite nanocrystal solution and 10-undecenoic acid CsPbBr₃Mixing the perovskite nano crystal solution according to the volume ratio of 2: 8, 5: 5 or 8: 2 respectively; the conditions of ultraviolet lamp illumination are as follows: and simultaneously, ultraviolet lamps with the wavelengths of 254nm and 365nm are adopted for illumination for 24 hours.

Technical Field

The invention relates to the technical field of preparation of inorganic luminescent materials, and particularly relates to CsPbBr with adjustable size₃Spindle typeA preparation method of perovskite micron particles.

Background

All-inorganic halide perovskite CsPbX₃Since the first report on (X ═ Cl, Br, I) quantum dots, their excellent performance has been continuously explored in 2015, and they have been widely used in the fields of light emitting diodes, solar cells, photodetectors, and the like. CsPbX₃The material has many advantages, firstly, the halogen perovskite CsPbX₃The half-peak width of the luminescence can easily reach below 20nm, and the photoluminescence color purity is ultrahigh. Second, CsPbX₃The exciton Bohr radius of the quantum dot is about 7nm, and theoretically, the crystal grain can show obvious quantum confinement effect only when the grain diameter is smaller than or close to the exciton Bohr radius. Although perovskite CsPbX₃(X ═ Cl, Br, I) has become a new star of materials rising, but it is quite sensitive to water and oxygen, has poor stability in air, and its luminous efficiency drops significantly in a short time of standing, which greatly limits its application in the field of photovoltaics.

It is well known that the size, dimension and morphology of a material have a great influence on its properties, and that they can be manipulated to improve the material properties. At present, to improve perovskite CsPbX₃The stability and the luminous performance in the air are proved by researchers to synthesize perovskite nanocrystals with various shapes such as nano-blocks, nano-sheets, nano-rods and the like to regulate and improve the performance of the material, but the perovskite CsPbX prepared by the prior art₃The size of the material is in the nanometer scale, and the materials have the problems of wide band gap, small radiation recombination efficiency coefficient, low color purity and short luminescence life, thereby seriously influencing the photoelectric property of the material; in addition, the preparation method in the prior art cannot realize continuous and accurate regulation and control of the morphology and the size of the material, so that the regulation and control of the luminescence life and the regulation and control of the luminescence performance are realized, and the CsPbBr with higher luminescence purity and adjustable luminescence life cannot be regulated and controlled at one time according to the luminescence performance requirement of the product₃Perovskite microparticles.

Disclosure of Invention

The purpose of the invention is toThe defects are overcome, and the size-adjustable CsPbBr is provided₃A preparation method of spindle-type perovskite micron particles. The invention takes 5-hexynoic acid and 10-undecaynoic acid as surface ligands, and CsPbBr with different length-width ratios can be prepared by adjusting the volume of crystal solution obtained by the two surface ligands₃Spindle-type perovskite microparticles. The preparation method is simple, continuous and accurate regulation and control of the shape and size of the material are realized, so that regulation and control of the luminescence life and the luminescence performance are realized, and CsPbBr with high luminescence purity and adjustable luminescence life can be prepared at one time₃The spindle-type perovskite micron particles can be suitable for materials with different illumination requirements. The spindle-type perovskite CsPbBr prepared by the method₃The micron particles have the advantages of uniform appearance, good dispersibility, adjustable aspect ratio of the particles, small band gap, narrow luminous half-peak width, high color purity, long luminous service life, excellent photoelectric property and wide application prospect in the fields of screen display, illumination and the like.

The technical scheme of the invention is as follows:

the invention provides CsPbBr with adjustable size₃The preparation method of the spindle-type perovskite micron particles comprises the steps of firstly respectively preparing 5-hexynoic acid CsPbBr by taking 5-hexynoic acid and 10-undecenoic acid as surface ligands₃Perovskite nanocrystal solution and 10-undecenoic acid CsPbBr₃Perovskite nanocrystal solution, adding 5-hexynoic acid CsPbBr₃Perovskite nanocrystal solution and 10-undecenoic acid CsPbBr₃Mixing the perovskite nano crystal solutions according to different volume ratios, and finally placing the mixed solutions under the illumination of an ultraviolet lamp for reaction to obtain CsPbBr with different length-width ratios₃Spindle-type perovskite microparticles. By adjusting 5-hexynoic acid CsPbBr₃Perovskite nanocrystal solution and 10-undecenoic acid CsPbBr₃Volume ratio regulation CsPbBr of perovskite nanocrystal solution₃Aspect ratio of spindle-type perovskite microparticles.

The 5-hexynoic acid CsPbBr₃Perovskite nanocrystal solution and 10-undecenoic acid CsPbBr₃Calcium titaniumThe volume ratio of the mineral nano crystal solution is 2: 8-8: 2.

The reaction conditions of ultraviolet lamp illumination are as follows: simultaneously, ultraviolet lamps with the wavelengths of 254nm and 365nm are adopted for illumination for 12-36 hours.

The preparation method comprises the following steps:

(1) heating and stirring cesium salt, octadecene and oleic acid under the protection of nitrogen until the cesium salt, octadecene and oleic acid are completely dissolved to obtain a standby solution;

(2) mixing lead bromide, octadecene, oleylamine and 5-hexynoic acid, stirring at constant temperature under the protection of nitrogen until the lead bromide, octadecene, oleylamine and 5-hexynoic acid are completely dissolved, quickly injecting the standby solution obtained in the step (1) at the temperature of 140-150 ℃, cooling to room temperature after stirring, adding absolute ethyl alcohol for washing, discarding supernatant after centrifugation, dissolving precipitate in cyclohexane, centrifuging again, and collecting supernatant to obtain 5-hexynoic acid CsPbBr₃A perovskite nanocrystal solution;

(3) mixing lead bromide, octadecene, oleylamine and 10-undecaynoic acid, stirring at constant temperature under the protection of nitrogen until the lead bromide, octadecene, oleylamine and 10-undecaynoic acid are completely dissolved, quickly injecting the standby solution obtained in the step (1) at the temperature of 160-170 ℃, cooling to room temperature after stirring, adding absolute ethyl alcohol for washing, centrifuging, discarding supernate, dissolving the precipitate in cyclohexane, centrifuging again, collecting supernate, and obtaining 10-undecaynoic acid CsPbBr₃A perovskite nanocrystal solution;

(4) the 5-hexynoic acid CsPbBr is added₃Perovskite nanocrystal solution and 10-undecenoic acid CsPbBr₃Mixing perovskite nano crystal solutions according to different volume ratios, and finally placing the mixed solutions in a dark box type ultraviolet lamp for acetylene bond coupling reaction in a constant temperature environment to obtain CsPbBr with different length-width ratios₃Spindle-type perovskite microparticles.

The cesium salt is any one of cesium carbonate, cesium bromide or cesium acetate. Preferably, the cesium salt is cesium carbonate.

In the step (1), 0.2-0.3 g of cesium carbonate, 10-20 ml of octadecene and 0.75-1.5 ml of oleic acid are used.

In the step (2), 0.1-0.2 g of lead bromide, 10-20 ml of octadecene, 1-3 ml of oleylamine and 0.2-0.4 ml of 5-hexynoic acid are used; taking 0.8-1.2 ml of the solution for later use in the step (1); the volume of the cyclohexane is 5-15 ml.

In the step (3), 0.1-0.2 g of lead bromide, 10-20 ml of octadecene, 1-3 ml of oleylamine and 0.03-0.06 g of 10-undecaynoic acid are used; taking 0.8-1.2 ml of the solution for later use in the step (1); the volume of the cyclohexane is 5-15 ml.

The constant-temperature stirring temperature is 100-120 ℃; the centrifugation condition is that the centrifugation is carried out for 5 to 10 minutes at the rotating speed of 8000 to 10000 revolutions per minute.

Preferably, in the step (4), 5-hexynoic acid CsPbBr₃Perovskite nanocrystal solution and 10-undecenoic acid CsPbBr₃Mixing the perovskite nano crystal solution according to the volume ratio of 2: 8, 5: 5 or 8: 2 respectively; the conditions of ultraviolet lamp illumination are as follows: and simultaneously, ultraviolet lamps with the wavelengths of 254nm and 365nm are adopted for illumination for 24 hours.

The invention has the beneficial effects that:

(1) the invention takes 5-hexynoic acid and 10-undecaynoic acid as surface ligands, and CsPbBr with different length-width ratios can be prepared by adjusting the volume of crystal solution obtained by the two surface ligands₃Spindle-type perovskite microparticles. The preparation method is simple, continuous and accurate regulation and control of the shape and size of the material are realized, so that regulation and control of the luminescence life and the luminescence performance are realized, and CsPbBr with high luminescence purity and adjustable luminescence life can be prepared at one time₃The spindle-type perovskite micron particles can be suitable for materials with different illumination requirements. The size-adjustable spindle-type perovskite CsPbBr prepared by the method₃The micron particles have the advantages of uniform appearance, good dispersibility, adjustable aspect ratio of the particles, small band gap, narrow luminous half-peak width, high color purity, long luminous service life, excellent photoelectric property and wide application prospect in the fields of screen display, illumination and the like.

(2) The CsPbBr can be prepared by the preparation method₃Spindle-type perovskite microparticles, and CsPbBr can be regulated and controlled by adjusting the volume ratio of nanocrystal solutions of two different ligands₃The aspect ratio of spindle-type perovskite micron particles realizes the accurate control of the morphology of the micron particles after illumination, and the perovskite CsPbBr is improved₃The luminescent property of the material has the advantages of narrow luminescent half-peak width, high color purity, long service life and the like.

(3) The invention adopts terminal alkynoic acid 5-hexynoic acid and 10-undecaynoic acid as surface ligands, carboxyl groups contained in the two surface ligands can form coordination action on the surface of the perovskite, and the invention has the function of protecting materials and can improve the perovskite CsPbBr₃Stability of (2); and functional group acetylene bonds at the other ends of the two surface ligands can react freely to induce the material to be assembled, and CsPbBr with different length-width ratios can be prepared under the regulation and control of the two acetylenic acid ligands₃Spindle-type perovskite microparticles.

(4) The method adopts an ultraviolet lamp for illumination reaction, the ultraviolet lamp can provide energy to promote the reaction, the method is simple and convenient, a compound CsBr is generated in the process, the compound CsBr can catalyze acetylene bonds to generate coupling reaction more quickly under illumination, the self-assembly of perovskite nanocrystals is facilitated, and CsPbBr with different length-width ratios is successfully obtained₃The spindle-type perovskite material has important significance for expanding the application of the spindle-type perovskite material in the photoelectric field.

(5) The invention adopts two different terminal alkynoic acid ligands to prepare CsPbBr with different length-width ratios₃Spindle-type perovskite micron particles and CsPbBr prepared by only using one terminal alkynoic acid ligand and having no adjustable length-width ratio₃Compared with spindle type perovskite micron particles, the micron particles obtained by the invention have narrower luminous half-peak width and higher luminous color purity; preparation of CsPbBr of different aspect ratios using two terminal alkynoic acids₃The fluorescence lifetime of the spindle-type perovskite micro-particles can be regulated and controlled within a certain interval according to the luminescence requirement, and the lifetime is longer.

Drawings

FIG. 1 shows CsPbBr with aspect ratio of 5.5 in example 1 of the present invention₃Scanning electron microscope image of spindle type perovskite micron particles.

FIG. 2 shows CsPbBr with aspect ratio of 4.0 in example 1 of the present invention₃Scanning electron microscope image of spindle type perovskite micron particles.

FIG. 3 shows CsPbBr with aspect ratio of 2.25 in example 1 of the present invention₃Scanning electron microscope image of spindle type perovskite micron particles.

FIG. 4 shows three aspect ratios CsPbBr in example 1 of the present invention₃XRD pattern of spindle-type perovskite microparticles.

FIG. 5 shows two aspect ratios CsPbBr in example 2 of the present invention₃XRD pattern of spindle-type perovskite microparticles.

FIG. 6 shows two aspect ratios CsPbBr in example 3 of the present invention₃XRD pattern of spindle-type perovskite microparticles.

FIG. 7 shows CsPbBr in comparative example 1 of the present invention₃Scanning electron microscope image of spindle type perovskite micron particles.

FIG. 8 shows CsPbBr in comparative example 1 of the present invention₃XRD pattern of spindle-type perovskite microparticles.

Fig. 9 shows the XRD pattern of the perovskite CsPbBr3 nanoparticles of comparative example 2 of the present invention.

FIG. 10 shows perovskite CsPbBr in comparative example 3 of the present invention₃XRD pattern of nanoparticles.

FIG. 11 shows fluorescence lifetime spectra of materials in cuvettes No. 1, 8 and 9 in test example 1 of the present invention.

FIG. 12 shows fluorescence emission spectra of materials numbered 1, 8 and 9 in test example 2 of the present invention.

Detailed Description