阅读说明：本技术 一种全无机钙钛矿纳米晶及其制备方法和在半导体器件上的应用 (All-inorganic perovskite nanocrystalline, preparation method thereof and application thereof in semiconductor device ) 是由 倪亮 肖也 于 2019-09-18 设计创作，主要内容包括：本发明属于半导体器件材料技术领域,公开一种全无机钙钛矿纳米晶及其制备方法和在半导体器件上的应用。该方法包括步骤：将乙酸铯前驱液和溴化铅前驱液混合,磁力搅拌后超声处理,充分溶解获得混合液,依次滴入油酸和氢溴酸水溶液,继续搅拌,并将溶液温度加热至40℃,随后通过超声使容器壁上前驱体充分反应,制得CsPbBr<Sub>3</Sub>钙钛矿前驱液；静置后分层,把上层清液滤除,向沉淀中滴入二甲基亚砜,继续搅拌,直至溶液呈现亮绿色,然后置于真空干燥箱内,待溶液挥发后,得到产物。该材料在空气中稳定可控、导电性良好、具有较高的光致发光量子产率,可以直接应用于半导体器件,亦可充当光敏剂帮助提高其他材料的光学性能。(The invention belongs to the technical field of semiconductor device materials, and discloses an all-inorganic perovskite nanocrystal, a preparation method thereof and application thereof in a semiconductor device. The method comprises the following steps: mixing cesium acetate precursor solution and lead bromide precursor solution, performing ultrasonic treatment after magnetic stirring, fully dissolving to obtain mixed solution, sequentially dripping oleic acid and hydrobromic acid aqueous solution, continuously stirring, heating the solution to 40 ℃, and then fully reacting the precursors on the container wall by ultrasonic to obtain CsPbBr 3 A perovskite precursor liquid; standing, layering, filtering supernatant, dripping dimethyl sulfoxide into precipitate, stirring until the solution is bright green, and then placing in a vacuum drying oven to obtain the product after the solution is volatilized. The material is stable and controllable in air, good in conductivity and high in photoluminescence quantum yield, can be directly applied to semiconductor devices, and can also be used as a photosensitizer to helpImprove the optical performance of other materials.)

1. A preparation method of all-inorganic perovskite nanocrystals is characterized by comprising the following operation steps: mixing cesium acetate precursor solution and lead bromide precursor solution, performing ultrasonic treatment after magnetic stirring, fully dissolving to obtain mixed solution, sequentially dripping oleic acid and hydrobromic acid aqueous solution, continuously stirring, heating the solution to 40 ℃, and then fully reacting the precursors on the container wall by ultrasonic to obtain CsPbBr ₃A perovskite precursor liquid; reacting CsPbBr ₃And (3) standing the perovskite precursor solution, then layering, filtering supernatant liquor, dripping dimethyl sulfoxide into the precipitate, continuously stirring until the solution is bright green, then placing the solution in a vacuum drying oven, and volatilizing the solution to obtain the all-inorganic perovskite nanocrystalline.

2. The method of claim 1, wherein: the cesium acetate precursor solution is prepared by dispersing cesium acetate crystals in dimethyl sulfoxide, wherein the molar volume ratio of the cesium acetate crystals to the dimethyl sulfoxide is (0.8) m mol: 0.5 ml; the lead bromide precursor solution is prepared by dispersing lead bromide powder in dimethyl sulfoxide, wherein the molar volume ratio of the lead bromide powder to the dimethyl sulfoxide is (0.8-1.6) m mol: 0.5 ml; the mol ratio of the cesium acetate crystals to the lead bromide powder is 0.8 mmol: (0.8 to 1.6) m mol.

3. The method of claim 1, wherein: the speed of the magnetic stirring is 1000-1500 rpm, and the time of ultrasonic treatment is 10-30 min.

4. The method of claim 1, wherein: the volume ratio of the dropping amount of the oleic acid to the mixed solution is 0.5: 1.

5. the method of claim 1, wherein: the volume percentage of hydrobromic acid in the aqueous hydrobromic acid solution is 48%, and the volume ratio of the aqueous hydrobromic acid solution to oleic acid is 0.5: 0.5.

6. the method of claim 1, wherein: and (3) dropwise adding dimethyl sulfoxide into the precipitate, wherein the volume ratio of the dimethyl sulfoxide to the oleic acid is (0.5-1) ml: 0.5 ml.

7. An all-inorganic perovskite nanocrystal prepared by the preparation method of any one of claims 1 to 6.

8. Use of the all-inorganic perovskite nanocrystals according to claim 7 in the preparation of semiconductor devices, characterized in that: the semiconductor device is prepared according to the following steps: dissolving all-inorganic perovskite nanocrystalline in n-hexane or toluene to prepare CsPbBr ₃A perovskite solution; reacting CsPbBr ₃Dropping the perovskite solution on FTO or ITO conductive glass, carrying out spin coating, heating to 50-100 ℃, and plating a gold electrode on the spin-coated perovskite layer to obtain the semiconductor device.

9. Use according to claim 8, characterized in that: the spin coating speed is 2000-4000 rpm, and the time is 20-60 s; the gold plating electrode is a traditional photoetching process.

Technical Field

The invention belongs to the technical field of semiconductor device materials, and particularly relates to an all-inorganic perovskite (CsPbBr) ₃) A nanocrystal, a preparation method thereof and application thereof in a semiconductor device.

Background

Semiconductor devices are electronic devices that have electrical conductivity between a good electrical conductor and an insulator, and that use the special electrical properties of semiconductor materials to perform specific functions, and can be used to generate, control, receive, convert, amplify signals, and perform energy conversion. The importance of semiconductors is enormous, both from a technological and economic point of view. In recent years, metal halide perovskite materials exhibit excellent photoelectric properties, have the characteristics of high crystallinity, high carrier mobility, low exciton confinement energy, high quantum efficiency, wide absorption spectrum, high light absorption coefficient, low energy consumption loss and the like, and are a second focus of materials research field.

The general molecular formula of the metal halide perovskite is ABX3, at present, the metal halide perovskite material is mainly applied to the aspect of solar cells, the metal halide perovskite cells are used in the photovoltaic industry, and the conversion rate of the metal halide perovskite cells reaches 25.2%. It is noted that, although the application effect of pure inorganic metal halide perovskite on solar cells is general, the inorganic perovskite thin film has outstanding performance on photoelectric conversion efficiency. And the forbidden band width (Eg) of the CsPbBr3 perovskite nanocrystal is 2.3eV, so that the CsPbBr3 perovskite nanocrystal has excellent photoelectric property, can respond to most visible light, and has good charge transfer capability and photo-generated electron capability. The smaller the grain size of the pure inorganic perovskite CsPbBr3 is, the larger the surface area, the shorter the photon-generated carrier transfer path, the lower the defect state and the better the photoluminescence quantum yield. In addition, the CsPbBr3 perovskite nano-crystal with small particle size and a two-dimensional semiconductor material can be combined, and the photoelectric property of the two-dimensional material is improved in an auxiliary manner under the role of a photosensitizer.

As CsPbBr3 perovskite per se, it is easy to produce CsPbBr3 perovskite with low quantum yield during synthesis, and this defect tends to directly affect the performance of semiconductor devices made from such low quantum yield perovskites.

Disclosure of Invention

In order to overcome the defects and shortcomings in the prior art, the invention mainly aims to provide a preparation method of all-inorganic perovskite nanocrystals.

The invention further aims to provide the all-inorganic perovskite nanocrystalline prepared by the preparation method.

It is a further object of the present invention to provide the use of the above all inorganic perovskite nanocrystals.

The purpose of the invention is realized by the following technical scheme:

full inorganic calcium titaniumThe preparation method of the mineral nanocrystalline comprises the following operation steps: mixing cesium acetate precursor solution and lead bromide precursor solution, performing ultrasonic treatment after magnetic stirring, fully dissolving to obtain mixed solution, sequentially dripping oleic acid and hydrobromic acid aqueous solution, continuously stirring, heating the solution to 40 ℃, and then fully reacting the precursors on the container wall by ultrasonic to obtain CsPbBr ₃A perovskite precursor liquid; reacting CsPbBr ₃And (3) standing the perovskite precursor solution, then layering, filtering supernatant liquor, dripping dimethyl sulfoxide into the precipitate, continuously stirring until the solution is bright green, then placing the solution in a vacuum drying oven, and volatilizing the solution to obtain the all-inorganic perovskite nanocrystalline.

The cesium acetate precursor solution is prepared by dispersing cesium acetate crystals in dimethyl sulfoxide, wherein the molar volume ratio of the cesium acetate crystals to the dimethyl sulfoxide is (0.8) m mol: 0.5 ml; the lead bromide precursor solution is prepared by dispersing lead bromide powder in dimethyl sulfoxide, wherein the molar volume ratio of the lead bromide powder to the dimethyl sulfoxide is (0.8-1.6) m mol: 0.5 ml; the mol ratio of the cesium acetate crystals to the lead bromide powder is 0.8m mol: (0.8 to 1.6) m mol.

The speed of the magnetic stirring is 1000-1500 rpm, and the time of ultrasonic treatment is 10-30 min.

The volume ratio of the dropping amount of the oleic acid to the mixed solution is 0.5: 1.

the volume percentage of hydrobromic acid in the aqueous hydrobromic acid solution is 48%, and the volume ratio of the aqueous hydrobromic acid solution to oleic acid is 0.5: 0.5.

and (3) dropwise adding dimethyl sulfoxide into the precipitate, wherein the volume ratio of the dimethyl sulfoxide to the oleic acid is (0.5-1) ml: 0.5 ml.

The all-inorganic perovskite nanocrystal prepared by the preparation method.

The application of the all-inorganic perovskite nanocrystal in preparing a semiconductor device is prepared according to the following steps: dissolving all-inorganic perovskite nanocrystalline in n-hexane or toluene to prepare CsPbBr ₃A perovskite solution; reacting CsPbBr ₃Dropping perovskite solution on FTO or ITO conductive glass, spin-coating, addingAnd heating to 50-100 ℃, and plating a gold electrode on the spin-coated perovskite layer to obtain the semiconductor device.

The spin coating speed is 2000-4000 rpm, and the time is 20-60 s; the gold plating electrode is a traditional photoetching process.

Compared with the prior art, the invention has the following advantages and effects:

(1) the preparation raw materials can be synthesized in the air, the perovskite nanocrystalline which stably exists in the air can be prepared, the optical response range is wide, the reasonable energy band width is wide, the electrical conductivity is good, the photo-generated carriers are easy to separate and transfer, and the preparation method can be applied to semiconductor material devices.

(2) The invention has the characteristics of simple control on reaction conditions, easy operation of equipment, low production cost, no pollution and the like in the preparation process, and the reaction temperature and time are easy to control, so that the application of the material in a semiconductor device provides a new reference.

(3) CsPbBr prepared by the invention ₃After the perovskite nanocrystalline is purified, perovskite with low fluorescence quantum yield is abandoned, the prepared material is small in particle size and large in surface area, extremely high fluorescence quantum yield can be provided, and the perovskite prepared in the whole process is high in yield and has the best structural stability.

Drawings

Fig. 1 is an SEM photograph of the all-inorganic perovskite nanocrystals prepared in examples 1 and 2.

Fig. 2 is an X-ray powder diffraction pattern and standard spectrum of the all-inorganic perovskite nanocrystals prepared in examples 1 and 2.

Fig. 3 is an I-V curve of a semiconductor device of the all-inorganic perovskite nanocrystals prepared in examples 1 and 2.

Fig. 4 and 5 are photoluminescence quantum yields of the all-inorganic perovskite nanocrystals prepared in examples 1 and 2, respectively.

Detailed description of the invention

The present invention will be described in further detail with reference to examples, but the embodiments of the present invention are not limited thereto.