阅读说明：本技术 一种二氧化硅单颗粒包裹锰掺杂纯无机钙钛矿的纳米晶及其制备方法和应用 (Nanocrystalline of manganese-doped pure inorganic perovskite coated by silicon dioxide single particles and preparation method and application thereof ) 是由 陈威威 黄义 唐孝生 于 2020-06-28 设计创作，主要内容包括：本发明涉及一种二氧化硅单颗粒包裹锰掺杂纯无机钙钛矿的纳米晶及其制备方法和应用,属于纳米材料技术领域。本发明的纳米晶具有核壳结构,即使用作为壳的球形二氧化硅单颗粒对单个的锰掺杂纯无机钙钛矿材料的核进行包覆,得到具有良好分散性和光学性能的纳米晶,解决现有技术中由于传统SiO<Sub>2</Sub>包覆方式由于SiO<Sub>2</Sub>体积较大、锰掺杂材料团聚而引起的光学性能较差等问题,在太阳能电池、LED、微激光等领域具有广泛的应用前景。另外本发明提供的一种二氧化硅单颗粒包裹锰掺杂纯无机钙钛矿的纳米晶的制备方法,其制备过程中二氧化硅颗粒的生长可控,同时制备方法简单、容易操作。(The invention relates to a nanocrystalline of manganese-doped pure inorganic perovskite coated by silicon dioxide single particles, a preparation method and application thereof, belonging to the technical field of nano materials. The nanocrystalline has a core-shell structure, namely the spherical silicon dioxide single particle used as the shell coats the core of a single manganese-doped pure inorganic perovskite material to obtain the nanocrystalline with good dispersibility and optical performance, and the problem that the conventional SiO is used in the prior art is solved 2 The coating mode is due to SiO 2 The volume is large, the optical performance is poor due to the agglomeration of the manganese-doped material, and the like, and the method has wide application prospects in the fields of solar cells, LEDs, micro lasers and the like. In addition, the preparation method of the nanocrystalline of the manganese-doped pure inorganic perovskite coated by the single silicon dioxide particles has the advantages of controllable growth of the silicon dioxide particles in the preparation process, simple preparation method and easy operation.)

1. The nanocrystalline of the manganese-doped pure inorganic perovskite material is coated by silicon dioxide single particles and is characterized in that the nanocrystalline is of a core-shell structure, wherein the shell is spherical silicon dioxide particles, and the core is a single manganese-doped pure inorganic perovskite nanocrystalline material.

2. The nanocrystal of claim 1, wherein the pure inorganic perovskite is CsPbX₃Wherein X is Cl or Br.

3. A method for preparing a nanocrystal, as claimed in any one of claims 1 to 2, comprising the steps of:

(1) adding trioctylphosphine into a toluene solution of a manganese-doped pure inorganic perovskite material, and stirring to react for 30 min;

(2) adding tetraethyl silicate continuously, stirring and reacting for 10 min;

(3) and then ammonia water is added to hydrolyze the tetraethyl silicate to obtain the nano-crystalline of the pure inorganic perovskite material doped with manganese and wrapped by silicon dioxide single particles.

4. The production method according to claim 3, wherein the manganese-doped pure inorganic perovskite material is produced by:

(1) dissolving lead chloride, lead bromide and manganese halide in octadecene, adding oleic acid and oleylamine as stabilizing agents, stirring for 20min under nitrogen, heating to 120 ℃, preserving heat for 30min, heating to 170 ℃, preserving heat for 10min, continuing heating to 200 ℃, preserving heat for 10min, adding oleic acid and oleylamine until the solution becomes clear, and obtaining a lead halide precursor;

(2) firstly, adding an oleic acid-cesium precursor into the lead halide precursor in the step (1), reacting for 10s, then placing in an ice water bath for cooling, and purifying to obtain the manganese-doped pure inorganic perovskite material.

5. The preparation method of claim 4, wherein the mass ratio of the lead chloride to the lead bromide to the manganese halide is 66:66:80, and the mass-to-volume ratio of the lead chloride to the oleic acid in the stabilizer to the oleylamine in the stabilizer is 66:1.6:1.6, and mg: mL: mL.

6. The method according to claim 4, wherein the molar ratio of lead in the lead halide precursor to cesium in the oleic acid-cesium precursor is 10: 3.

7. The preparation method according to claim 4, wherein the purification is carried out by: adding n-hexane and ethyl acetate into the mixed solution cooled in the ice-water bath according to the volume ratio of 1:3, centrifuging for 5min at 8000rpm, taking the lower-layer solid part, and repeating the operation twice.

8. The preparation method according to claim 3, wherein the volume-to-mass ratio of the manganese-doped pure inorganic perovskite material, trioctylphosphine, tetraethyl silicate and ammonia water is 15:30:200:10, and mg: μ L: μ L.

9. The production method according to claim 3, wherein the concentration of the manganese-doped pure inorganic perovskite material in the toluene solution of the manganese-doped pure inorganic perovskite material is 5 mg/mL.

10. Use of the nanocrystals according to any one of claims 1 to 2 in solar cells, LEDs or micro lasers.

Technical Field

The invention belongs to the technical field of nano materials, and particularly relates to a nano crystal of manganese-doped pure inorganic perovskite coated by silicon dioxide single particles, and a preparation method and application thereof.

Background

In recent years, all-inorganic perovskite nanocrystals (CsPbX)₃X ═ Cl, Br, I) can be determined by their spectraThe characteristics of high modulation and luminous efficiency, high half-height width and the like show great application value in the fields of solar cells, micro lasers, light emitting diodes and the like. However, since the all-inorganic perovskite nanocrystals contain the toxic element Pb and their crystal structures exhibit instability due to strong ion mobility, further commercial applications of the nanocrystals are greatly limited. In order to reduce the toxicity of perovskite nanocrystals, researchers have been working on reducing or replacing the lead Pb element with non-toxic elements (Ge, Sb, Bi, Sn). However, lead-free perovskite nanocrystals tend to exhibit low luminous efficiency, poor stability, and the like. The perovskite nanocrystalline doped with the transition metal element manganese can endow the perovskite nanocrystalline with novel optical and electrical properties, but the perovskite nanocrystalline formed by manganese doping is easy to deteriorate and show instability when meeting water and oxygen.

Although SiO is present₂Coating perovskite nanocrystals is an important way to improve their stability. However, conventional SiO₂SiO formed by cladding₂The nano-crystalline silicon material is often large in volume, and more nano-crystalline is contained in the nano-crystalline silicon material to be aggregated together, and the aggregated nano-crystalline is very unfavorable for preparing photoelectric devices.

Therefore, there is a need to further study new methods for wrapping manganese-doped all-inorganic perovskite nanocrystals with single silica particles, so as to improve the stability of manganese-doped all-inorganic perovskite nanocrystals while at the same time reducing the coated SiO₂Volume, thereby increasing SiO₂Optical properties of the coated perovskite nanocrystalline material.

Disclosure of Invention

In view of the above, an object of the present invention is to provide a nanocrystal of manganese-doped pure inorganic perovskite coated with single silica particle; the second purpose of the invention is to provide a preparation method of a nanometer crystal of manganese-doped pure inorganic perovskite wrapped by silicon dioxide single particles; the invention also aims to provide application of the nanocrystalline of the manganese-doped pure inorganic perovskite coated by the silicon dioxide single particles in solar cells, LEDs or micro lasers.

In order to achieve the purpose, the invention provides the following technical scheme:

1. a nanocrystalline of a manganese-doped pure inorganic perovskite material wrapped by silicon dioxide single particles is of a core-shell structure, wherein the shell is spherical silicon dioxide particles, and the core is a single manganese-doped pure inorganic perovskite nanocrystalline material.

Preferably, the pure inorganic perovskite is CsPbX₃Wherein X is Cl or Br.

2. The preparation method of the nanocrystalline comprises the following steps:

(1) adding Trioctylphosphine (TOP) into a toluene solution of manganese-doped pure inorganic perovskite nano-crystals, and stirring for reaction for 30 min;

(2) continuously adding tetraethyl silicate (TEOS), and stirring and reacting for 10 min;

(3) and then ammonia water is added to hydrolyze the tetraethyl silicate to obtain the nano-crystalline of the pure inorganic perovskite material doped with manganese and wrapped by silicon dioxide single particles.

Preferably, the manganese-doped pure inorganic perovskite material is prepared according to the following method:

(1) dissolving lead chloride, lead bromide and manganese halide in octadecene, adding Oleic Acid (OA) and oleylamine (OAm) as stabilizing agents, stirring for 20min under nitrogen, heating to 120 ℃, keeping the temperature for 30min, heating to 170 ℃, keeping the temperature for 10min, then continuously heating to 200 ℃, keeping the temperature for 10min, adding oleic acid and oleylamine until the solution becomes clear, and obtaining a lead halide precursor;

(2) firstly, adding an oleic acid-cesium precursor into the lead halide precursor in the step (1), reacting for 10s, then placing in an ice water bath for cooling, and purifying to obtain the manganese-doped pure inorganic perovskite material.

Preferably, the mass ratio of the lead chloride to the lead bromide to the manganese halide is 66:66:80, the mass-to-volume ratio of the lead chloride to the oleic acid in the stabilizer to the oleylamine in the stabilizer is 66:1.6:1.6, and the mass-to-volume ratio of the lead chloride to the oleic acid in the stabilizer to the oleylamine in the stabilizer is mg: mL: mL.

Preferably, the molar ratio of lead in the lead halide precursor to cesium in the oleic acid-cesium precursor is 10: 3.

Preferably, the specific way of purification is: adding n-hexane and ethyl acetate into the mixed solution cooled in the ice-water bath according to the volume ratio of 1:3, centrifuging for 5min at 8000rpm, taking the lower-layer solid part, and repeating the operation twice.

Preferably, the volume-to-mass ratio of the manganese-doped pure inorganic perovskite material to the trioctylphosphine to the tetraethyl silicate to the ammonia water is 15:30:200:10, and the volume-to-mass ratio of mg: muL to muL.

Preferably, the concentration of the manganese-doped pure inorganic perovskite material in the toluene solution of the manganese-doped pure inorganic perovskite material is 5 mg/mL.

3. The application of the nanocrystalline in solar cells, LEDs or micro lasers.

The invention has the beneficial effects that:

1. the invention provides a nanocrystalline of manganese-doped pure inorganic perovskite wrapped by single silicon dioxide particles, which is prepared to obtain a manganese-doped pure inorganic perovskite material, then Trioctylphosphine (TOP) is used for modification to partially replace a ligand (oleic acid/oleylamine) on the surface of the manganese-doped pure inorganic perovskite material and simultaneously prevent the material from contacting with moisture, finally tetraethyl silicate (TEOS) is used as a precursor of silicon, ammonia water is added to hydrolyze the precursor to form spherical silicon dioxide single particles, and the manganese-doped pure inorganic perovskite material is wrapped to finally obtain the nanocrystalline of a core-shell structure of the manganese-doped pure inorganic perovskite wrapped by the single silicon dioxide particles. The prepared nanocrystalline has a core-shell structure formed by wrapping a manganese-doped pure inorganic perovskite material with silicon dioxide single particles, has good dispersibility, excellent optical performance and good stability, and solves the problem that the perovskite nanocrystalline formed by manganese doping is easy to deteriorate and show instability when meeting water and oxygen; conventional SiO₂SiO of coating layer caused by coating mode₂The volume is large, the optical performance is poor due to the agglomeration of the manganese-doped material, and the like, and the method has wide application prospects in the fields of solar cells, LEDs, micro lasers and the like.

2. The invention also provides a preparation method of the nanocrystalline of the manganese-doped pure inorganic perovskite coated by the single silicon dioxide particles, the growth of the silicon dioxide particles is controllable in the preparation process, and the preparation method is simple and easy to operate.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the means of the instrumentalities and combinations particularly pointed out hereinafter.

Drawings

For the purposes of promoting a better understanding of the objects, aspects and advantages of the invention, reference will now be made to the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1 shows the preparation of nanocrystals of silica single-particle-encapsulated manganese-doped pure inorganic perovskite (CsPbMn (BrCl) in example 1₃@SiO₂) A flow chart of (1);

FIG. 2 shows a manganese-doped pure inorganic perovskite material (CsPbMn (BrCl)₃) Transmission electron microscopy images of (a);

FIG. 3 shows CsPbMn (BrCl)₃High resolution transmission electron microscopy images of (a);

FIG. 4 shows a silica single-particle encapsulated manganese-doped pure inorganic perovskite nanocrystal (CsPbMn (BrCl))₃@SiO₂) Transmission electron microscopy images of (a);

FIG. 5 shows CsPbMn (BrCl)₃@SiO₂High resolution transmission electron microscopy images of (a);

FIG. 6 shows CsPbMn (BrCl)₃Material (a) and CsPbMn (BrCl)₃@SiO₂An irradiation pattern of nanocrystals (b) under an ultraviolet lamp;

FIG. 7 shows CsPbMn (BrCl)₃@SiO₂Photoluminescence spectrum and ultraviolet-visible absorption spectrum of the nanocrystal.

Detailed Description

The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention. It should be noted that, in the following embodiments, features in the embodiments may be combined with each other without conflict.