Metal halide perovskite single crystal with high plqy and preparation method thereof

Abstract

The application discloses a metal halide perovskite single crystal with high PLQY and a preparation method thereof, and comprises the following steps: mixing SbX3 and diphenyl guanidine hydrohalide to obtain a solute; the molar ratio of SbX3 and diphenyl guanidine hydrohalide is 1:2-5; the solute is added into a transparent glass bottle, and an organic solvent is added into the transparent glass bottle and stirred until the solute is completely dissolved to form a solution; the solution is obtained by a slow solvent evaporation method or a cooling crystallization method operation; and the metal halide perovskite single crystal is obtained. The application proposes that the diphenyl guanidine is used as a cation to form a zero-dimensional non-lead metal halide perovskite, and since the dimension of the obtained halide perovskite structure is zero, compared with one-dimensional, two-dimensional and three-dimensional, the vibration freedom degree can be improved, which is beneficial to obtain a more efficient and lower-dimensional material and is beneficial to the formation of a self-trapped exciton (STE).

Description

TECHNICAL FIELD

[0001] The present application relates to the field of new functional materials, and particularly relates to a metal halide perovskite single crystal with high PLQY and a preparation method thereof. BACKGROUND

[0002] In the past few years, halide-lead perovskites have shown various superior optoelectronic properties, including high photoluminescence quantum yield (PLQY), narrow emission full width at half maximum (FWHM), wide color gamut, and excellent charge transport ability, leading to their extensive research in solar cells, photodetectors, light-emitting diodes, scintillators, lasers, etc. Unfortunately, lead-based perovskites are usually limited by poor moisture and heat stability, as well as the potential toxicity of lead, which severely restricts their practical applications.

[0003] Pb can be replaced by non-toxic multivalent cations, and non-lead metal halides such as CsSnX3, Cs2SnX6, Cs3Bi2X9, Cs3Sb2X9, etc. have been successfully realized. However, almost all of these compounds exhibit low PLQY due to a large number of defects or oxidation of the substituted cations. SUMMARY

[0004] The technical problem solved by the present application is to provide a metal halide perovskite single crystal with high PLQY and a preparation method thereof, so as to solve the problem of low PLQY of non-lead metal halides in the prior art.

[0005] To solve the above technical problems, one technical solution adopted by the present application is to provide a metal halide perovskite single crystal with high PLQY and a preparation method thereof, and the steps are as follows:

[0006] SbX3 and diphenyl guanidine hydrohalide are mixed to obtain a solute; the molar ratio of SbX3 and diphenyl guanidine hydrohalide is 1:2-5;

[0007] The solute is added to a transparent glass bottle, and an organic solvent is added to the transparent glass bottle and stirred until the solute is completely dissolved to form a solution;

[0008] The solution is obtained by slow solvent evaporation or cooling crystallization operation.

[0009] Further, X in SbX3 is a halide.

[0010] Further, X is Cl, Br or I.

[0011] Further, the organic solvent is methanol, ethanol or isopropanol.

[0012] Further, the stirring process is: putting a magnetic stirrer in a transparent glass bottle, stirring for 10-20 min on a magnetic stirrer, so that the solute is completely dissolved.

[0013] Further, the operation steps of the solvent slow evaporation method are:

[0014] Filtering the solution with polytetrafluoroethylene to remove impurities;

[0015] Injecting the filtered solution into a clean transparent glass bottle and sealing it with a cover with small holes; the diameter of the small holes is 0.2-0.8 cm;

[0016] Refrigerating the transparent glass bottle for 100-140 h to wait for the slow evaporation of the solvent, and finally generating a metal halide perovskite single crystal.

[0017] Further, the operation steps of the cooling crystallization method are:

[0018] Putting a high-temperature magnetic stirrer in a transparent glass bottle and sealing the cover, stirring for 15 min on a magnetic heating stirrer, and the heating temperature is 80-140 DEG C;

[0019] Putting the transparent glass bottle into an oven and cooling to room temperature at a cooling rate of 1 DEG C / 15 min, and finally generating a metal halide perovskite single crystal.

[0020] To solve the above technical problems, another technical solution adopted by the present application is to provide a metal halide perovskite single crystal with high PLQY, characterized by: a compound (C 13 H 13 N3)3SbX6 composed of hexahalogen antimony anion and N, N-diphenyl guanidinium cation obtained by the preparation method of any one of the above.

[0021] Further, the X is a halide.

[0022] Further, the X is Cl, Br or I.

[0023] The beneficial effects of the present application are:

[0024] 1. The present application proposes to use diphenyl guanidine as a cation to form a zero-dimensional non-lead metal halide perovskite, since the dimension of the obtained halide perovskite structure is zero, compared with one-dimensional, two-dimensional and three-dimensional, the vibration freedom can be improved, which is beneficial to obtain higher efficiency, lower dimensional material, and is beneficial to the formation of self-trapped excitons (STE).

[0025] 2. The application uses solvent slow evaporation method and cooling crystallization method to synthesize the above-mentioned material, the solvent slow evaporation method is simple in operation and easy to generate large-size single crystal material; the cooling method is convenient and fast, high in efficiency and yield, and convenient for industrialized production; and large-size and large-batch of the above-mentioned luminescent material can be prepared according to requirements.

[0026] 3. The (C 13 H 13 N3)3SbX6 single crystal material prepared by the application has a maximum size of centimeter level, and a PLQY of more than 80%.

[0027] In order to make the above and other objects, features and advantages of the present application more apparent, the following preferred embodiments are specifically described, and the accompanying drawings are described in detail as follows. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the present application or prior art, the following will briefly introduce the drawings needed to be used in the embodiments. Obviously, the drawings in the following description are only five drawings of the present application, and other drawings can be obtained by those skilled in the art without any creative effort.

[0029] Figure 1 is the (C 13 H 13 N3)3SbX6 absorption spectrum of the non-lead metal halide perovskite provided by the application;

[0030] Figure 2 is the photoluminescence spectrum of the non-lead metal halide perovskite (C 13 H 13 N3)3SbX6 material provided by the application;

[0031] Figure 3 is the crystal electron transmission microscope (TEM) of the non-lead metal halide perovskite (C 13 H 13 N3)3SbX6 provided by the application;

[0032] Figure 4 is the crystal powder X-ray diffraction contrast diagram (XRD) of the non-lead metal halide perovskite (C 13 H 13 N3)3SbX6 provided by the application;

[0033] Figure 5 is the crystal structure schematic diagram of the non-lead metal halide perovskite (C 13 H 13 N3)3SbX6 provided by the application. DETAILED DESCRIPTION

[0034] For the purpose of promoting the understanding of the present application, the present application will be described in further detail below with reference to the drawings and specific embodiments. The preferred embodiments of the present application are shown in the drawings. However, the present application can be realized in many different forms and is not limited to the embodiments described in this specification. On the contrary, these embodiments are provided for the purpose of making the disclosure of the present application more thorough and comprehensive.

[0035] It should be noted that, unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. The term "and / or" used in this specification includes any and all combinations of one or more related listed items.

[0036] Please refer to Figure 1 , Figure 1 The present application provides a metal halide perovskite single crystal with high PLQY, which is composed of hexahalogen antimony anion and N,N-diphenyl guanidinium cation, and a compound (C 13 H 13 N3)3SbX6; wherein X is halide or pseudohalide, preferably Cl, Br or I.

[0037] The preparation process of the metal halide perovskite single crystal will be described in detail below, taking Br as X and methanol as an organic solvent as an example.

[0038] The preparation of the metal halide perovskite single crystal can be carried out by solvent slow evaporation method or cooling crystallization method. The preparation process of the solvent slow evaporation method and the preparation process of the cooling crystallization method will be described below.

[0039] Example 1

[0040] One preparation step of the solvent slow evaporation method is:

[0041] Step a. Preparation of metal halide perovskite precursor: (1) Diphenyl guanidinium hydrobromide (C 13 H 13 N3.HBr) and antimony bromide (SbBr3) are mixed in a molar ratio of 2:1, such as 0.2 mmol C 13 H 13 N3.HBr and 0.1 mmol SbBr3 are dissolved in 2 ml of anhydrous methanol, sealed in a transparent glass bottle, and stirred at room temperature for 30 min.

[0042] (2) After complete dissolution, the solution was filtered using a polytetrafluoroethylene (0.45 um) syringe, and the filtered solution was injected into a vial, which was sealed with a paraffin film with a small hole (the process ensured quietness and reduced air flow to prevent the methanol from evaporating too quickly and generating crystals prematurely).

[0043] Step b. Growth of metal halide single crystals: The precursor in step a was injected into a clean glass bottle and sealed, leaving a small hole (about 0.2 cm in diameter) in the plastic glass cover to facilitate gas evaporation; the transparent glass bottle was placed in the refrigerator for 100 h to allow the solvent to evaporate slowly, and vibration and air flow were minimized during the growth process to obtain high-quality (C 13 H 13 N3)3SbBr6 single crystals.

[0044] Example Two

[0045] Another preparation step for the slow solvent evaporation method is:

[0046] Step a. Preparation of metal halide perovskite precursor: (1) Diphenyl guanidinium hydrobromide (C 13 H 13 N3.HBr) and antimony bromide (SbBr3) in a molar ratio of 3:1, such as 0.3 mmol C 13 H 13 N3.HBr (0.0876 g) and 0.1 mmol SbBr3 (0.0361 g) were dissolved in 2 ml of anhydrous methanol, placed in a transparent glass bottle, and sealed, and stirred at room temperature for 30 min.

[0047] (2) After complete dissolution, the solution was filtered using a polytetrafluoroethylene (0.45 um) syringe, and the filtered solution was injected into a vial, which was sealed with a paraffin film with a small hole.

[0048] Step b. Growth of metal halide single crystals: The precursor in step a was injected into a clean glass bottle and sealed, leaving a small hole (about 0.5 cm in diameter) in the plastic glass cover to facilitate gas evaporation; the transparent glass bottle was placed in the refrigerator for 120 h to allow the solvent to evaporate slowly, and vibration and air flow were minimized during the growth process to obtain high-quality (C 13 H 13 N3)3SbBr6 single crystals.

[0049] Example Three

[0050] Another preparation step for the slow solvent evaporation method is:

[0051] Step a. Preparation of metal halide perovskite precursor: (1) Diphenyl guanidinium hydrobromide (C 13H 13 N3.HBr) and antimony bromide (SbBr3) is 5:1, such as 0.5 mmol C 13 H 13 N3.HBr and 0.1 mmol SbBr3 are dissolved in 2 ml of anhydrous methanol, sealed in a transparent glass bottle, and stirred at room temperature for 30 min.

[0052] (2) After complete dissolution, the solution is filtered using a polytetrafluoroethylene (0.45 um) syringe, and the filtered solution is injected into a vial, which is sealed with a paraffin film with small holes.

[0053] Step b. Growth of metal halide single crystal: The precursor in step a is injected into a clean glass bottle, which is tightly sealed, leaving a small hole with a diameter of about 0.8 cm on the plastic glass cover to facilitate the volatilization of gas; the transparent glass bottle is placed in the refrigerator and left for 140 h to allow the solvent to slowly volatilize, and vibration and air flow are minimized during the growth process to obtain high-quality (C 13 H 13 N3)3SbBr6 single crystal.

[0054] Example Four

[0055] A preparation step of the cooling crystallization method is:

[0056] Step a. Preparation of metal halide perovskite precursor: (1) Diphenyl guanidine hydrobromide (C 13 H 13 N3.HBr) and antimony bromide (SbBr3) is 2:1, such as 3 mmol C 13 H 13 N3.HBr and 1 mmol SbBr3 are dissolved in 10 ml of anhydrous methanol, stirred at 80 degrees Celsius for 30 min, and placed in a sealed glass container (due to the boiling point of methanol being only 60 degrees Celsius, the pressure in the bottle increases).

[0057] Step b. Growth of metal halide single crystal: The transparent glass bottle in step a is placed in a temperature-controllable oven, and the temperature is set to decrease by 1 degree Celsius every 15 min until it reaches room temperature, at which time regular (C 13 H 13 N3)3SbBr6 single crystal material.

[0058] Example Five

[0059] A preparation step of the cooling crystallization method is:

[0060] Step a. Preparation of metal halide perovskite precursor: (1) Diphenyl guanidine hydrobromide (C 13 H 13N3.HBr) and antimony bromide (SbBr3) in a molar ratio of 3:1, such as 3mmol C 13 H 13 N3.HBr (0.876g) and 1mmol SbBr3 (0.361g) were dissolved in 10ml anhydrous methanol, stirred at 120 degrees Celsius for 30min, and placed in a fully sealed glass container.

[0061] Step b. Growth of metal halide single crystal: the transparent glass bottle in step a was placed in a temperature controllable oven, and the temperature was set to decrease by 1 degree Celsius every 15min until it dropped to room temperature, at which time regular (C 13 H 13 N3)3SbBr6 single crystal material appeared at the bottom of the cup.

[0062] Example six

[0063] A preparation step of the cooling crystallization method is:

[0064] Step a. Preparation of metal halide perovskite precursor: (1) Diphenyl guanidine hydrobromide (C 13 H 13 N3.HBr) and antimony bromide (SbBr3) in a molar ratio of 5:1, such as 3mmol C 13 H 13 N3.HBr and 1mmol SbBr3 were dissolved in 10ml anhydrous methanol, stirred at 140 degrees Celsius for 30min, and placed in a fully sealed glass container.

[0065] Step b. Growth of metal halide single crystal: the transparent glass bottle in step a was placed in a temperature controllable oven, and the temperature was set to decrease by 1 degree Celsius every 15min until it dropped to room temperature, at which time regular (C 13 H 13 N3)3SbBr6 single crystal material appeared at the bottom of the cup.

[0066] The (C 13 H 13 N3)3SbBr6 single crystal prepared in Example two was subjected to experimental test analysis.

[0067] It exhibits extremely strong yellow light emission under ultraviolet or blue light irradiation, and its absorption spectrum and emission spectrum are shown in FIGS. Figure 1 , 2, with an emission peak at 611nm, a half-peak width of 112nm, and a PLQY of 86.2%, having the characteristics of self-limited exciton emission, and being an excellent optical material.

[0068] Microscopic test analysis was performed, and the TEM image of the (C 13 H 13 N3)3SbBr6 material is shown in FIG.Figure 3 As shown, it is illustrated that the method of the present application can prepare crystals with good crystallinity.

[0069] The powder XRD test of the powder after grinding is compared with the single crystal data fitting, as shown in Figure 4 As shown, it is illustrated that the experimental results of the compound are consistent with the theoretical simulation.

[0070] Single crystal data analysis is performed, and the crystal structure diagram is as shown in Figure 5 As shown.

[0071] In summary, the preparation method of the present application is simple, efficient, and can meet the preparation of batch production and centimeter level single crystal, and the material has excellent optical performance, PLQY>80%, which is used in the field of laser, LED device, etc.

[0072] The above description of each embodiment tends to emphasize the differences between each embodiment, and the same or similar parts can be referred to each other, and for the sake of brevity, the present application will not be described again.

[0073] The above is only an embodiment of the present application, and is not limited to the patent range of the present application. Any equivalent structural transformation using the content of the specification and drawings, or direct or indirect application in other related technical fields, is also included in the patent protection range of the present application.

[0074] The above is only an embodiment of the present application, and is not limited to the patent range of the present application. Any equivalent structural transformation using the content of the specification and drawings, or direct or indirect application in other related technical fields, is also included in the patent protection range of the present application.

Claims

1. A method for preparing a metal halide perovskite single crystal with high PLQY, comprising the steps of: mixing SbX3 and diphenyl guanidine hydrohalide to obtain a solute; the molar ratio of SbX3 and diphenyl guanidine hydrohalide being 1:2-5; adding the solute into a transparent glass bottle, adding an organic solvent into the transparent glass bottle, and stirring until the solute is completely dissolved to form a solution; slowly evaporating the solvent or lowering the temperature to crystallize the solution to obtain a metal halide perovskite single crystal.

2. The SbX3 in the method is a halide.

3. The X is Cl, Br or I.

4. The organic solvent is methanol, ethanol or isopropanol.

5. The stirring process is placing a magnetic stirrer in the transparent glass bottle and stirring for 10-30 min on a magnetic stirrer to completely dissolve the solute.

2. The method of claim 1, wherein the method is characterized by:

6. The slowly evaporating the solvent operation comprises the steps of: filtering the solution with polytetrafluoroethylene to remove impurities; pouring the filtered solution into a clean transparent glass bottle and sealing with a cap having a small hole; the small hole having a diameter of 0.2-0.8 cm; and placing the transparent glass bottle in a refrigerator for 100-140 h to slowly evaporate the solvent to obtain a metal halide perovskite single crystal.

3. The method of claim 2, wherein the method is characterized by:

7. The lowering the temperature to crystallize operation comprises the steps of: placing a high-temperature magnetic stirrer in the transparent glass bottle and sealing the cap, and stirring for 15 min on a magnetic heating stirrer at a temperature of 80-140 °C; and placing the transparent glass bottle in an oven and lowering the temperature to room temperature at a rate of 1 °C / 15 min to obtain a metal halide perovskite single crystal.

4. The method of claim 3, wherein the method is characterized by:

8. The X is a halide.

5. The method of claim 4, wherein the method is characterized by:

9. The X is Cl, Br or I. ​ ​ ​ 6. The method of claim 4, wherein the method is characterized by: ​ ​ ​ 7. A metal halide perovskite single crystal with high PLQY, the steps of which are: obtaining a compound (C) consisting of hexahalostibine anions and N,N-diphenylguanidinium cations by the method of any one of claims 5 or 6. 13 H 13 N3)3SbX6; ​ 8. The metal halide perovskite single crystal with high PLQY according to claim 7, characterized in that: ​

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