CN108946808B

CN108946808B - All-inorganic cesium-bismuth/antimony halide perovskite nanocrystal and preparation method thereof

Info

Publication number: CN108946808B
Application number: CN201810659534.3A
Authority: CN
Inventors: 匡代彬; 王旭东; 李文倩; 谢瑶
Original assignee: Sun Yat Sen University
Current assignee: Sun Yat Sen University
Priority date: 2018-06-25
Filing date: 2018-06-25
Publication date: 2021-03-30
Anticipated expiration: 2038-06-25
Also published as: CN108946808A

Abstract

The invention provides an all-inorganic cesium-bismuth/antimony halide perovskite nanocrystalline and a preparation method thereof₃M₂X₉Microcrystalline material, then adding Cs₃M₂X₉Carrying out ultrasonic stripping on the microcrystalline material, and finally carrying out centrifugal purification to obtain Cs₃M₂X₉And (4) nanocrystals. By optimizing the material components and the preparation process, the size of the nanocrystalline can be adjusted within the range of 2-100 nm. The method has simple and rapid operation and good reproducibility. Cs prepared by the method₃M₂X₉The nano-crystalline has narrow size distribution and high stability, can be used for manufacturing photoelectric devices, and can be applied to the fields of solar cells, photoelectric detectors, photocatalysis, photoelectrocatalysis and the like.

Description

All-inorganic cesium-bismuth/antimony halide perovskite nanocrystal and preparation method thereof

Technical Field

The invention belongs to the field of preparation of novel inorganic nano materials, and particularly relates to all-inorganic Cs₃M₂X₉Perovskite nanocrystalline and preparation method thereof.

Background

Based on APbX₃(A：Cs、CH₃NH₃(MA); x: lead-based perovskite nanocrystals of Cl, Br, I) have the advantages of large absorption cross section, high fluorescence quantum efficiency, tunable luminescence over the entire ultraviolet/visible light range, and the like, and have attracted much attention in recent years. However, the perovskite nanocrystals contain lead, a toxic element, which greatly limits the development of the perovskite nanocrystals, and in addition, the perovskite nanocrystals have relatively poor stability. Therefore, the synthesis of perovskite nanocrystals with low toxicity and high stability becomes a current research hotspot. Bismuth-or antimony-based perovskite phase materials have been reported in recent years to suffer from certain properties due to their lower toxicity and higher stability than lead-based perovskitesAttention is paid to. But relatively little research has been directed to bismuth or antimony-based perovskite nanocrystals. The existing method for synthesizing the perovskite nano-crystal mainly focuses on a solvent-resistant method and a thermal injection method, and has the disadvantages of complex operation, harsh reaction conditions and relatively poor reproducibility.

Disclosure of Invention

Based on the method, the invention provides a preparation method of the all-inorganic cesium-bismuth/antimony halide perovskite nanocrystal, and the method is simple, convenient and quick to operate and good in reproducibility.

The preparation method of the all-inorganic cesium-bismuth/antimony halide perovskite nanocrystal comprises the following steps:

s1: preparation of Cs₃M₂X₉Microcrystalline material

Preparing Cs by wet method or solid phase synthesis method₃M₂X₉A microcrystalline material.

S2: preparation of Cs₃M₂X₉Nanocrystal

Mixing Cs₃M₂X₉Dispersing the microcrystalline material into an organic solvent, then carrying out ultrasonic stripping, and finally obtaining Cs in the supernatant through centrifugal purification₃M₂X₉And (4) nanocrystals.

Wherein, M is trivalent metal, and X is one or more of Cl, Br and I.

Compared with the prior art, the preparation method of the invention uses Cs₃M₂X₉The microcrystal material is ultrasonically stripped, and Cs with narrow size distribution, low defect density, no toxic Pb element and high stability can be synthesized₃M₂X₉The all-inorganic perovskite nanocrystalline is simple, convenient and quick to operate and good in reproducibility.

Further, M is one or two of Bi and Sb.

Further, in step S1, the wet method is to dissolve the halide metal salt, carbonate or metal oxide containing M element and the cesium-containing raw material in a solvent respectively to obtain two precursor solutions; the two precursor solutions are quickly mixed, stirred to obtain a large amount of precipitate, and the precipitate is dried to obtain Cs₃M₂X₉A microcrystalline material.

Furthermore, the solvent in the wet synthesis is one or a mixture of several of ethanol, methanol, DMF, DMSO, acetonitrile, water, halogen acid and the like.

Further, the solid-phase synthesis method in step S1 is a method in which a halide metal salt containing M element is solid-phase stirred with CsX at room temperature or sintered at 800 ℃ or lower to obtain Cs₃M₂X₉A microcrystalline material.

Further, a dispersant may be added to the organic solvent in step S2.

Further, the organic solvent is one or a mixture of halogenated alkane, aromatic hydrocarbon, alcohol, lipid, aldehyde and organic acid. The organic solvent can well disperse Cs₃M₂X₉Microcrystalline material without the combination of Cs₃M₂X₉The microcrystalline material reacts, changing its structure.

Further, the dispersing agent is one or a mixture of a plurality of solvents such as oleic acid, propionic acid and the like. The use of the dispersing agent can reduce the agglomeration of the nanocrystalline and improve the dispersing performance.

Cs prepared according to the above method₃M₂X₉The nanocrystalline can be used for manufacturing photoelectric devices, and can be applied to the fields of solar cells, photoelectric detectors, photocatalysis, photoelectrocatalysis and the like.

Drawings

FIG. 1 shows Cs₃Bi₂Cl₉XRD pattern of microcrystalline material;

FIG. 2 shows Cs₃Bi₂Cl₉SEM images of microcrystalline material;

FIG. 3 shows Cs₃Bi₂Cl₉A TEM image of the nanocrystal;

FIG. 4 shows Cs₃Bi₂Br₉XRD pattern of microcrystalline material;

FIG. 5 shows Cs₃Bi₂Br₉SEM images of microcrystalline material;

FIG. 6 shows Cs₃Bi₂Br₉A TEM image of the nanocrystal;

FIG. 7 shows Cs₃Bi₂I₉XRD pattern of microcrystalline material;

FIG. 8 shows Cs₃Bi₂I₉SEM images of microcrystalline material;

FIG. 9 shows Cs₃Bi₂I₉A TEM image of the nanocrystal;

FIG. 10 shows Cs₃Bi₂I₉XRD pattern of nanocrystals;

FIG. 11 shows Cs₃Sb₂I₉XRD pattern of microcrystalline material;

FIG. 12 shows Cs₃Sb₂I₉SEM images of microcrystalline material;

FIG. 13 shows Cs₃Sb₂I₉TEM images of the nanocrystals.

Detailed Description

The invention uses an ultrasonic stripping method to prepare Cs₃M₂X₉The nanocrystalline can synthesize the Cs with narrow size distribution and high stability and can be used for manufacturing optoelectronic devices₃M₂X₉The full inorganic perovskite nanocrystalline is simple, convenient and quick to operate and good in reproducibility. The technical solution of the present invention is described in detail below with reference to the accompanying drawings by way of specific embodiments.

Example 1

S1-1: preparation of Cs₃Bi₂Cl₉Microcrystalline material

3mmol CsCl and 2mmol BiCl₃Grinding at normal temperature after mixing to obtain Cs₃Bi₂Cl₉A microcrystalline material.

S2-1: preparation of Cs₃Bi₂Cl₉Nanocrystal

0.2g of Cs is taken₃Bi₂Cl₉The microcrystalline material was dispersed in 20mL chloroform and sonicated at 300W sonication power for 20 minutes (4 seconds sonication, 4 second intervals). After low-speed centrifugation at 500rpm, the lower pellet was discarded. Then centrifuging the supernatant at 3000rpm, discarding the precipitate to obtain Cs in the supernatant₃Bi₂Cl₉And (4) nanocrystals.

Please refer to fig. 1, which illustrates a schematic diagram of a systemCs₃Bi₂Cl₉XRD pattern of microcrystal material, Cs prepared by said invention₃Bi₂Cl₉Characteristic diffraction peak of (A) and ICSD #2067Cs₃Bi₂Cl₉The perfect coincidence of the card information proves that pure Cs is obtained₃Bi₂Cl₉. Please refer to FIG. 2, which shows Cs₃Bi₂Cl₉SEM image of microcrystalline material. FIG. 2 shows that Cs prepared by the present invention₃Bi₂Cl₉The crystallite material size is mainly distributed between 2 and 8 mu m.

Please refer to fig. 3, which shows Cs₃Bi₂Cl₉TEM images of the nanocrystals. FIG. 3 shows Cs prepared by the present invention₃Bi₂Cl₉The size of the nano crystal is mainly distributed between 20 nm and 70 nm.

Example 2

S1-2: preparation of Cs₃Bi₂Br₉Microcrystalline material

1.5mmol of Cs₂CO₃，2mmol BiBr₃Respectively dissolved in 10mL of hydrobromic acid, and stirred for 1 hour at 100 ℃ to be fully dissolved to obtain two precursor solutions. Quickly mixing the two precursor solutions at normal temperature, filtering to obtain a large amount of precipitate, and drying the precipitate in a drying oven to obtain Cs₃Bi₂Br₉A microcrystalline material.

S2-2: preparation of Cs₃Bi₂Br₉Nanocrystal

0.2g of Cs is taken₃Bi₂Br₉The microcrystalline material was dispersed in 20mL chloroform and sonicated at 300W sonication power for 20 minutes (4 seconds sonication, 4 second intervals). Centrifuging at 500rpm, discarding the lower precipitate, and collecting Cs in the supernatant₃Bi₂Br₉And (4) nanocrystals.

Referring to FIG. 4, Cs is shown₃Bi₂Br₉XRD pattern of microcrystal material, Cs prepared by said invention₃Bi₂Br₉Characteristic diffraction peak of (1) and ICSD #1142Cs₃Bi₂Br₉The card information is matched, and the pure Cs is proved to be obtained₃Bi₂Br₉. Please refer to FIG. 5, which shows Cs₃Bi₂Br₉SEM image of microcrystalline material. FIG. 5 shows Cs prepared according to the present invention₃Bi₂Br₉The crystallite material size is mainly distributed between 2 and 7 mu m.

Referring to FIG. 6, Cs is shown₃Bi₂Br₉TEM images of the nanocrystals. FIG. 6 shows Cs prepared according to the present invention₃Bi₂Br₉The nanocrystal size is mainly distributed between 2-5 nm.

Example 3

S1-3: preparation of Cs₃Bi₂I₉Microcrystalline material

Adding 3mmol CsI and 2mmol BiI₃Respectively dissolved in 10mL of hydroiodic acid, and stirred for 1 hour at 100 ℃ to fully dissolve the hydroiodic acid to obtain two precursor solutions. Quickly mixing the two precursor solutions at normal temperature, filtering to obtain a large amount of precipitate, and drying the precipitate in a drying oven to obtain Cs₃Bi₂I₉A microcrystalline material.

S2-3: preparation of Cs₃Bi₂I₉Nanocrystal

0.2g of Cs is taken₃Bi₂I₉The microcrystalline material was dispersed in 20mL chloroform and sonicated at 300W sonication power for 20 minutes (4 seconds sonication, 4 second intervals). Then centrifuging at low speed of 500rpm, discarding the bottom precipitate, and obtaining Cs in the supernatant₃Bi₂I₉And (4) nanocrystals.

Referring to FIG. 7, Cs is shown₃Bi₂I₉XRD pattern of microcrystal material, Cs prepared by said invention₃Bi₂I₉Characteristic diffraction peak and PDF #23-0847Cs₃Bi₂I₉The card information is matched, and the pure Cs is proved to be obtained₃Bi₂I₉. Please refer to FIG. 8, which shows Cs₃Bi₂I₉SEM image of microcrystalline material. FIG. 8 shows Cs prepared by the present invention₃Bi₂I₉The microcrystalline material has 2-5 μm domain and about 500nm thickness.

Please refer to FIG. 9And FIG. 10, the present invention produces Cs of relatively pure structure₃Bi₂I₉Nanocrystalline and of size about 13 nm.

Example 4

S1-4: preparation of Cs₃Sb₂I₉Microcrystalline material

3mmol CsI, 1mmol Sb₂O₃Respectively dissolved in 10mL of hydroiodic acid, and stirred for 1 hour at 100 ℃ to fully dissolve the hydroiodic acid to obtain two precursor solutions. Quickly mixing the two precursor solutions at normal temperature, filtering to obtain a large amount of precipitate, and drying the precipitate in a drying oven to obtain Cs₃Sb₂I₉A microcrystalline material.

S2-4: preparation of Cs₃Sb₂I₉Nanocrystal

0.2g of Cs is taken₃Sb₂I₉The microcrystalline material was dispersed in 20mL chloroform and sonicated at 300W sonication power for 20 minutes (4 seconds sonication, 4 second intervals). Then centrifuging at low speed of 500rpm, discarding the bottom precipitate, and obtaining Cs in the supernatant₃Sb₂I₉And (4) nanocrystals.

Please refer to fig. 11, which shows Cs₃Sb₂I₉XRD pattern of microcrystal material, Cs prepared by said invention₃Sb₂I₉Characteristic diffraction peak of (A) and ICSD #300002Cs₃Sb₂I₉The card information is matched, and the pure Cs is proved to be obtained₃Sb₂I₉. Please refer to FIG. 12, which shows Cs₃Sb₂I₉SEM image of microcrystalline material. FIG. 12 shows Cs prepared according to the present invention₃Sb₂I₉The microcrystalline material has a domain of 1-5 μm and a thickness of about 500 nm. Referring to FIG. 13, Cs prepared by the present invention₃Sb₂I₉The size of the nano crystal is 12-30 nm.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention.

Claims

1. A preparation method of all-inorganic cesium-bismuth/antimony halide perovskite nanocrystals comprises the following steps:

s1: preparation of Cs₃M₂X₉Microcrystalline material

Preparing Cs by wet method or solid phase synthesis method₃M₂X₉A microcrystalline material;

the wet method comprises the steps of respectively dissolving halide metal salt, carbonate or metal oxide containing M element and cesium-containing raw materials in a solvent to obtain two precursor solutions; fully mixing the two precursor solutions to obtain a large amount of precipitate, and drying the precipitate to obtain Cs₃M₂X₉A microcrystalline material;

the solid phase synthesis method is to mix the halide metal salt containing M element with CsX solid phase at normal temperature or sinter at 800 deg.C to obtain Cs₃M₂X₉A microcrystalline material;

s2: preparation of Cs₃M₂X₉Nanocrystal

Mixing Cs₃M₂X₉Dispersing the microcrystalline material into an organic solvent, then carrying out ultrasonic stripping, and finally obtaining Cs in the supernatant through centrifugal purification₃M₂X₉A nanocrystal;

wherein, M is trivalent metal, and X is one or more of Cl, Br and I.

2. The method of claim 1, wherein: and M is one or the mixture of Bi and Sb.

3. The method of claim 1, wherein: the organic solvent is one or a mixture of halogenated alkane, aromatic hydrocarbon, alcohol, lipid, aldehyde and organic acid.