CN116812964A - Preparation method of copper-based perovskite powder - Google Patents

Abstract

The invention provides a preparation method of copper-based perovskite powder, which belongs to the technical field of photoelectric functional materials. In the present invention, CsX powder and CuX powder are mixed and then a polar solvent is added for grinding. After drying, copper-based perovskite powder is obtained; the X is Cl, Br or I. The preparation method provided by the invention solves the problem that uneven local reactions easily lead to impurities in the product when copper-based perovskite is prepared by conventional grinding methods. The copper-based perovskite obtained by the preparation method of the invention has less impurities and the product is pure. , and the preparation method is simple, the raw material utilization rate is high, and mass production can be carried out.

Description

Preparation method of copper-based perovskite powder

Technical Field

The invention relates to the technical field of photoelectric functional materials, in particular to a preparation method of copper-based perovskite powder.

Background

The limitations of current lead halide perovskites have hindered their further commercialization, mainly due to the toxicity of the lead atoms, the potential for contamination of groundwater by water solubility of the lead atoms, and the chemical instability of the perovskite structure under high temperature, oxygen, moisture and even light. Researchers are currently looking for other elements to replace lead atoms to develop new, low cost, non-toxic and environmentally friendly perovskite materials that can be used in a variety of applications with excellent performance and long term stability.

The metal Cu is a candidate for replacing Pb in the metal halide family due to the outstanding photoelectric property, abundant resources, low price, environmental protection, no toxicity and the like. Copper-based perovskite attracts a great deal of attention from many researchers because of its excellent photoelectric properties as lead-based perovskite materials.

The current method for synthesizing copper-based perovskite mainly comprises a hot injection method, an antisolvent method, a grinding method and the like. Compared with the high-temperature preparation of the heat injection method and the small-amount synthesis of the anti-solvent method, the grinding method or the ball milling process has the advantages of large-scale preparation at room temperature, environmental protection and the like. However, in the preparation process of the grinding method and the ball milling process, the partial reaction is uneven, so that the product is easy to have impurities and even does not emit light. There is therefore a need to find better preparation processes in order to obtain high quality copper-based perovskite materials.

Disclosure of Invention

In view of the above, the present invention aims to provide a method for preparing copper-based perovskite powder, which has the advantages of less impurities and high fluorescence quantum yield.

In order to achieve the above object, the present invention provides the following technical solutions: a preparation method of copper-based perovskite powder comprises mixing CsX powder with CuX powder, adding polar solvent, grinding, and drying to obtain copper-based perovskite powder; and X is Cl, br or I.

Preferably, the molar ratio of CsX to CuX is (3-6): 4-6.

Preferably, the polar solvent is added in an amount that allows the mixed powder of CsX powder and CuX powder to be fully infiltrated.

Preferably, the polar solvent is water, absolute ethanol, methanol, dimethyl sulfoxide or dimethylformamide, more preferably absolute ethanol.

Preferably, the milling time is 5-10min.

The beneficial technical effects are as follows: the invention provides a preparation method of copper-based perovskite powder, which has the following advantages compared with the prior art:

1. the method solves the problem that impurities are easy to occur in the product due to uneven local reaction when the copper-based perovskite is prepared by the conventional grinding method, and the copper-based perovskite prepared by the method has few impurities and is pure.

2. The copper-based perovskite obtained by the preparation method provided by the invention has better luminous performance.

3. The preparation method provided by the invention is simple, has high raw material utilization rate, and can be used for mass production.

Drawings

FIG. 1 shows Cs obtained in example 1 ₃ Cu ₂ Cl ₅ Fluorescent pattern under 254nm ultraviolet lamp irradiation;

FIG. 2 shows Cs obtained in example 1 ₃ Cu ₂ Cl ₅ An XRD pattern of (b);

FIG. 3 shows Cs obtained in example 1 ₃ Cu ₂ Cl ₅ Scanning electron microscope images of (2);

FIG. 4 shows Cs of example 1 ₃ Cu ₂ Cl ₅ An excitation spectrum and an emission spectrum of (a);

FIG. 5 is a CsCu obtained in example 2 ₂ Cl ₃ Fluorescent pattern under 254nm ultraviolet lamp irradiation;

FIG. 6 is a CsCu obtained in example 2 ₂ Cl ₃ Is a XRD pattern of (C).

Fig. 7 is an XRD pattern of the sample obtained in comparative example 1.

Detailed Description

For a better understanding of the present invention, the following examples are further illustrated, but are not limited to the following examples.

Example 1 to example 6

And mixing CsX powder with CuX powder, adding 3ml of absolute ethyl alcohol, grinding for 5 minutes in a mortar, and drying to obtain the copper-based perovskite material.

The proportions of the raw materials in examples 1 to 6 are shown in Table 1.

Table 1 example 1 to example 6 ratios of raw materials

	Sample name	X	CsX(mmol)	CuX(mmol)
					Example 1	Cs 3 Cu 2 Cl 5	Cl	0.6	0.4
Example 2	CsCu 2 Cl 3	Cl	0.3	0.6
					Example 3	Cs 3 Cu 2 Br 5	Br	0.6	0.4
Example 4	CsCu 2 Br 3	Br	0.3	0.6
					Example 5	Cs 3 Cu 2 I 5	I	0.6	0.4
Example 6	CsCu 2 I 3	I	0.3	0.6

Cs obtained in example 1 ₃ Cu ₂ Cl ₅ As can be seen from FIG. 1, cs is irradiated under 254nm UV lamp ₃ Cu ₂ Cl ₅ Green fluorescence can be emitted.

For Cs obtained in example 1 ₃ Cu ₂ Cl ₅ As can be seen from FIG. 2, XRD characterization is performed, and diffraction peaks and Cs of the obtained sample ₃ Cu ₂ Cl ₅ The diffraction peaks of the standard PDF card of the crystal correspond to each other one by one, so that the prepared sample is Cs ₃ Cu ₂ Cl ₅ The crystal is pure, and the sample is free of impurities.

For Cs obtained in example 1 ₃ Cu ₂ Cl ₅ Scanning electron microscopy was performed and as can be seen from fig. 3, the sample size was on the order of microns.

From FIG. 4, cs of example 1 ₃ Cu ₂ Cl ₅ The excitation spectrum and the emission spectrum of the sample can be seen that the strongest peak position of the excitation spectrum of the sample is 307nm, that is, the strongest fluorescence emission can be obtained by ultraviolet light excitation of 307 nm. The emission peak has the strongest peak position of 532nm and is in the green light area.

CsCu obtained in example 2 ₂ Cl ₃ Irradiation under 254nm UV lamp, as can be seen in FIG. 5, csCu ₂ Cl ₃ Green fluorescence can be emitted.

For CsCu obtained in example 2 ₂ Cl ₃ As can be seen from FIG. 6, the diffraction peaks of the obtained samples were compared with CsCu by XRD characterization ₂ Cl ₃ The diffraction peaks of the standard PDF card of the crystal correspond to each other one by one, so that the prepared sample is CsCu ₂ Cl ₃ The crystal is pure, and the sample is free of impurities.

Comparative example 1

The same as in example 1 was repeated except that absolute ethanol was replaced with n-hexane.

XRD characterization of the sample obtained in comparative example 1, as can be seen from FIG. 7, the diffraction peaks of the obtained sample were compared with Cs ₃ Cu ₂ Cl ₅ The diffraction peak of the standard PDF card of the crystal corresponds well, so the prepared sample is Cs ₃ Cu ₂ Cl ₅ Crystals, but XRD contains peaks of impurities, i.e. samples other than Cs are prepared ₃ Cu ₂ Cl ₅ Crystals with CsCu present ₂ Cl ₃ Crystals and unreacted CsCl.

Example 7

The difference is that the absolute ethanol is replaced by methanol as in example 1.

XRD characterization of the resulting sample was performed, and the result was similar to that of example 1, and the prepared sample was Cs ₃ Cu ₂ Cl ₅ The crystal is pure, and the sample is free of impurities.

Example 8

The difference is that the absolute ethanol is replaced by dimethyl sulfoxide as in example 2.

XRD characterization of the obtained sample was performed, and the result was similar to example 2, and the prepared sample was CsCu ₂ Cl ₃ The crystal is pure, and the sample is free of impurities.

Example 9

The difference is that the absolute ethanol is replaced by dimethylformamide as in example 2.

XRD characterization of the obtained sample was performed, and the result was similar to example 2, and the prepared sample was CsCu ₂ Cl ₃ The crystal is pure, and the sample is free of impurities.

The foregoing is merely a preferred embodiment of the present invention and it should be noted that modifications and adaptations to those skilled in the art may be made without departing from the principles of the present invention, which are intended to be comprehended within the scope of the present invention.

Claims (5)

1. The preparation method of the copper-based perovskite powder is characterized in that CsX powder and CuX powder are mixed and then added with a polar solvent for grinding, and the copper-based perovskite powder is obtained after drying; and X is Cl, br or I.

2. The method of claim 1, wherein the molar ratio of CsX to CuX is (3-6): 4-6.

3. The method according to claim 1, wherein the polar solvent is added in an amount such that the mixed powder of CsX powder and CuX powder is fully infiltrated.

4. A method of preparation according to claim 1 or 3, wherein the polar solvent is water, absolute ethanol, methanol, dimethyl sulfoxide or dimethylformamide.

5. The method of claim 1, wherein the milling time is 5-10 minutes.