CN112898967B - A low-temperature solution synthesis process of a novel long-persistence perovskite crystal - Google Patents

Abstract

The invention discloses a low-temperature solution method synthesis process of a novel long-afterglow perovskite crystal, which comprises the following steps: 1) Putting cesium chloride, silver chloride, indium chloride, manganese chloride, ethylene diamine tetraacetic acid and concentrated hydrochloric acid into a polytetrafluoroethylene inner container, and then sealing the polytetrafluoroethylene inner container in a stainless steel high-pressure kettle; 2) Putting a stainless steel high-pressure autoclave into a muffle furnace, heating to 180 ℃ within 1h, keeping for 12h, slowly cooling the muffle furnace to 80 ℃ within 24-106 h, and finally naturally cooling to room temperature; 3) Opening the reaction kettle, discarding the upper liquid, placing the bottom crystal on absorbent paper, washing the single crystal for 3-5 times by using isopropanol, and adsorbing the isopropanol on the surface by using filter paper to obtain the perovskite long afterglow crystal; the invention avoids the high-temperature calcination process faced by the long-lasting long-afterglow material, realizes the long-afterglow performance of the single crystal material, and provides possibility for the application of the long-afterglow material in the fields of noctilucent jewels and the like.

Description

A low-temperature solution synthesis process of a novel long-persistence perovskite crystal

technical field

The invention relates to the technical field of material science, in particular to a low-temperature solution method synthesis process of a novel long-afterglow perovskite crystal.

Background technique

Long afterglow material is a light-storage luminescent material that can continue to emit light for hours or even weeks after the excitation source is removed. The long-lasting luminescent mechanism mainly involves the interaction of two active centers in the material, including the luminescent center and the trap center. The trap center can store light energy under the excitation of the excitation light source, and transfer the energy to the luminescent center under the action of thermal disturbance after the excitation stops, thus producing continuous luminescence. The depth of the center of the trap determines the length of the afterglow, and its density determines the brightness of the afterglow. Therefore, the controllable design of the trap centers is the key to the controllable preparation of long-afterglow materials.

The traditional long afterglow materials are mostly oxides or sulfur oxides, while the trap centers are mostly oxygen vacancies or some kind of metal ions with variable valence, which have higher formation energy. In order to obtain such traps, long-term high-temperature calcination under reducing atmosphere is usually required. For example, the typical green long afterglow material SrAl ₂ O ₄ : Eu ²⁺ , Dy ³⁺ needs to be calcined at 1400°C for 15 hours in a hydrogen atmosphere, which increases the cost of material synthesis due to safety and industrial energy consumption. Although the recently developed silicate matrix (such as CdSiO ₃ ) requires a lower calcination temperature (900°C), the toxicity of cadmium is a defect that cannot be ignored. In addition, the high-temperature calcination process will introduce inevitable sintering aggregation, which will cause the precursors such as nanomaterials to lose their morphology, and hinder the application of long-afterglow materials in biological cells. Therefore, it is a major challenge to develop a non-toxic long-lasting material system and its low-temperature synthesis process.

Contents of the invention

The invention provides a low-temperature solution synthesis process of a novel long-afterglow perovskite crystal.

The scheme of the present invention is:

A low-temperature solution synthesis process for a novel long-lasting perovskite crystal, comprising the following steps:

1) Put cesium chloride, silver chloride, indium chloride, manganese chloride, disodium edetate and concentrated hydrochloric acid into the polytetrafluoroethylene liner according to the stoichiometric ratio, and then put the polytetrafluoroethylene The liner is sealed in a stainless steel autoclave;

2) Put the stainless steel autoclave into the muffle furnace, heat it to 180°C within 1h, and keep it for 12h, slowly cool the muffle furnace to 80°C within 24-106h, and finally cool it naturally to room temperature;

3) Open the reactor, discard the upper liquid, place the bottom crystal on absorbent paper, and rinse the single crystal with isopropanol for 3 to 5 times, then use filter paper to absorb the isopropanol on the surface to obtain perovskite long afterglow crystals .

As a preferred technical solution, the step 1) concentrated hydrochloric acid is hydrochloric acid with a concentration of 36-38%.

As _a preferred technical solution, in the step ₁ ), cesium chloride _{, silver} chloride, indium chloride, manganese chloride, ethylenediaminetetra Put disodium acetate and concentrated hydrochloric acid into the polytetrafluoroethylene liner, where 0.05≤X≤0.3, 0.05≤Y≤0.3.

As a preferred technical solution, the X is 0.2, the Y is 0.2, and the concentrated hydrochloric acid is 12 mL.

As a preferred technical proposal, the manganese element contained in the manganese chloride is different from the sodium element contained in the disodium ethylenediaminetetraacetic acid, and the perovskite long afterglow crystals with different afterglow decay times can be obtained.

As a preferred technical solution, the feed ratio of the manganese element contained in the manganese chloride to the sodium element contained in the disodium edetate is 6:1-36.

As a preferred technical solution, the total mass of cesium chloride, silver chloride, indium chloride, manganese chloride and disodium edetate is 0.7315g.

As a preferred technical solution, the indium chloride is 1 mmol.

Owing to having adopted above-mentioned technical scheme, a kind of low-temperature solution synthesis process of novel long afterglow perovskite crystal comprises the following steps: 1) according to stoichiometric dosage ratio, cesium chloride, silver chloride, indium chloride, manganese chloride, Put disodium edetate and concentrated hydrochloric acid into the polytetrafluoroethylene liner, and then seal the polytetrafluoroethylene liner in a stainless steel autoclave;

2) Put the stainless steel autoclave into the muffle furnace, heat it to 180°C within 1h, and keep it for 12h, slowly cool the muffle furnace to 80°C within 24-106h, and finally cool it naturally to room temperature;

3) Open the reactor, discard the upper liquid, place the bottom crystal on absorbent paper, and rinse the single crystal with isopropanol for 3 to 5 times, then use filter paper to absorb the isopropanol on the surface to obtain perovskite long afterglow crystals .

The invention has the advantages that the perovskite long afterglow crystal color obtained in the invention is lavender, has high transparency and distinct crystal planes. Under the excitation of 365nm ultraviolet light, it shows yellow light, 400-800nm, and after turning off the light source, it shows red afterglow, 620nm, and the time can last for more than 1 hour;

The invention avoids the long-standing high-temperature calcination process faced by long-lasting materials, realizes the long-lasting performance of single crystal materials, and provides the possibility for the application of long-lasting materials in luminous gemstones and other fields;

(1) The crystal material obtained by this process has the characteristics of ultraviolet absorption and can be excited by sunlight. After the excitation is stopped, it has a long red afterglow of more than one hour, and the synthesis yield is more than 70%, and it can be stored in a container with a cover for more than one year;

(2) The synthesis temperature of the process of the present invention is 180°C, which can effectively reduce industrial energy consumption and production costs, while the synthesis of other traditional long afterglow materials requires high-temperature calcination above 900°C.

(3) The present invention relates to solution method synthesis, which avoids high-temperature sintering, and can adjust the size and shape of crystals through surfactants, etc., which provides the possibility for the development of nano-scale long-lasting crystals.

(4) The afterglow of the crystal involved in the present invention is pure red, and the spectrum does not drift with time.

Description of drawings

Figure 1 is a schematic diagram of the reaction of Cs ₂ Na _0.2 Ag _0.8 InCl ₆ :20% Mn perovskite long afterglow crystal; the column in the figure is a hydrothermal kettle, which is the reaction vessel for the reaction;

Figure 2 is the UV-Vis absorption spectrum, photoexcitation spectrum and photoemission spectrum of Cs ₂ Na _0.2 Ag _0.8 InCl ₆ :20% Mn perovskite long afterglow crystal;

Figure 3 is the long afterglow decay curve measured after the Cs ₂ Na _0.2 Ag _0.8 InCl ₆ :20% Mn perovskite long afterglow crystal was irradiated with 345nm ultraviolet light for 5 minutes and the excitation was stopped. The emission wavelength was monitored at 620nm; After that, the luminous intensity is still more than 10 times higher than the background noise;

Figure 4 shows the Cs ₂ Na _0.2 Ag _0.8 InCl ₆ : 20% Mn perovskite long afterglow crystals irradiated with 345nm ultraviolet light for 10 minutes, and after stopping the excitation, at 1 minute, 3 minutes, 5 minutes, 10 minutes and 30 minutes Measured red afterglow emission spectrum.

Detailed ways

In order to make up for the above deficiencies, the present invention provides a low-temperature solution synthesis process of a novel long-persistence perovskite crystal to solve the above-mentioned problems in the background technology.

A low-temperature solution synthesis process for a novel long-lasting perovskite crystal, specifically comprising the following steps:

1) Put cesium chloride, silver chloride, indium chloride, manganese chloride, disodium edetate and concentrated hydrochloric acid into a 25mL polytetrafluoroethylene liner, and then put the polytetrafluoroethylene liner Sealed in a stainless steel autoclave;

2) Put the stainless steel autoclave into the muffle furnace, heat it to 180°C within 1h, and keep it for 12h, slowly cool the muffle furnace to 80°C within 24-106h, and finally cool it naturally to room temperature;

3) Open the reactor, discard the upper liquid, place the bottom crystal on absorbent paper, and rinse the single crystal with isopropanol for 3 to 5 times, then use filter paper to absorb the isopropanol on the surface to obtain perovskite long afterglow crystals (Feeding is based on the ratio of InCl ₃ to 1mmoL, concentrated hydrochloric acid is 12mL, and the specification of the polytetrafluoroethylene liner is 25mL. The system can also be expanded in equal proportions to obtain long-lasting crystals. For example, the feeding is based on InCl ₃ is 4mmoL Proportionally input, the concentrated hydrochloric acid is 48mL, and the specification of the polytetrafluoroethylene liner is 100mL).

The step 1) concentrated hydrochloric acid is hydrochloric acid with a concentration of 36-38%.

The consumption of concentrated hydrochloric acid in described step 1) is 12mL.

The manganese element contained in the manganese chloride is different from the sodium element contained in the disodium ethylenediaminetetraacetic acid, so that crystals with different afterglow decay times can be obtained.

The feeding ratio of the manganese element contained in the manganese chloride to the sodium element contained in the disodium edetate is 6:1-36.

The total mass of cesium chloride, silver chloride, indium chloride, manganese chloride and disodium edetate is 0.7315g.

The indium chloride is 1 mmol.

In order to make the technical means, creative features, goals and effects achieved by the present invention easy to understand, the present invention will be further described below in conjunction with specific embodiments.

Example 1:

1) Put cesium chloride, silver chloride, indium chloride, manganese chloride, edetate disodium and concentrated hydrochloric acid into the polytetrafluoroethylene liner according to the chemical dosage ratio, and then put the polytetrafluoroethylene The liner is sealed in a stainless steel autoclave;

2) Put the stainless steel autoclave into the muffle furnace, heat it to 180°C within 1h, and keep it for 12h, slowly cool the muffle furnace to 80°C within 24 hours, and finally cool it naturally to room temperature;

3) Open the reactor, discard the upper liquid, place the bottom crystal on absorbent paper, and rinse the single crystal with isopropanol for 3 to 5 times, then use filter paper to absorb the isopropanol on the surface to obtain perovskite long afterglow crystals .

The step 1) concentrated hydrochloric acid is hydrochloric acid with a concentration of 36-38%.

In the step 1), cesium chloride, silver chloride, indium chloride, manganese chloride, disodium edetate and concentrated hydrochloric acid are mixed according to the stoichiometric ratio Cs ₂ Na _X Ag _1-X InCl ₆ : Y Mn Put it into a polytetrafluoroethylene liner, where X is 0.05 and Y is 0.05.

The concentrated hydrochloric acid is 12mL.

The manganese element contained in the manganese chloride is different from the sodium element contained in the disodium ethylenediaminetetraacetic acid, and the perovskite long afterglow crystal with different afterglow decay time can be obtained.

The feeding ratio of the manganese element contained in the manganese chloride to the sodium element contained in the disodium edetate is 1:1.

The indium chloride is 1 mmol.

Example 2:

1) Put cesium chloride, silver chloride, indium chloride, manganese chloride, disodium edetate and concentrated hydrochloric acid into the polytetrafluoroethylene liner according to the chemical dosage ratio, and then put the polytetrafluoroethylene The liner is sealed in a stainless steel autoclave;

2) Put the stainless steel autoclave into the muffle furnace, heat it to 180°C within 1h, and keep it for 12h, slowly cool the muffle furnace to 80°C within 106h, and finally cool it naturally to room temperature;

3) Open the reactor, discard the upper liquid, place the bottom crystal on absorbent paper, and rinse the single crystal with isopropanol for 3 to 5 times, then use filter paper to absorb the isopropanol on the surface to obtain perovskite long afterglow crystals .

The step 1) concentrated hydrochloric acid is hydrochloric acid with a concentration of 36-38%.

In the step 1), cesium chloride, silver chloride, indium chloride, manganese chloride, disodium edetate and concentrated hydrochloric acid are mixed according to the stoichiometric ratio Cs ₂ Na _X Ag _1-X InCl ₆ : Y Mn Put it into a polytetrafluoroethylene liner, where X is 0.3 and Y is 0.3.

The concentrated hydrochloric acid is 12mL.

The manganese element contained in the manganese chloride is different from the sodium element contained in the disodium ethylenediaminetetraacetic acid, and the perovskite long afterglow crystal with different afterglow decay time can be obtained.

The feeding ratio of the manganese element contained in the manganese chloride to the sodium element contained in the disodium edetate is 1:1.

The indium chloride is 1mmol

Example 3:

1) Put cesium chloride, silver chloride, indium chloride, manganese chloride, disodium edetate and concentrated hydrochloric acid into the polytetrafluoroethylene liner according to the stoichiometric ratio, and then put the polytetrafluoroethylene The liner is sealed in a stainless steel autoclave;

2) Put the stainless steel autoclave into the muffle furnace, heat it to 180°C within 1h, and keep it for 12h, slowly cool the muffle furnace to 80°C within 48h, and finally cool it naturally to room temperature; (as shown in Figure 1 Show);

3) Open the reactor, discard the upper liquid, place the bottom crystal on absorbent paper, and rinse the single crystal with isopropanol for 3 to 5 times, then use filter paper to absorb the isopropanol on the surface to obtain perovskite long afterglow crystals .

The step 1) concentrated hydrochloric acid is hydrochloric acid with a concentration of 36-38%.

In the step 1), cesium chloride, silver chloride, indium chloride, manganese chloride, disodium edetate and concentrated hydrochloric acid are mixed according to the stoichiometric ratio Cs ₂ Na _X Ag _1-X InCl ₆ : Y Mn Put it into a polytetrafluoroethylene liner, where X is 0.2 and Y is 0.2.

The consumption of concentrated hydrochloric acid in described step 1) is 12mL.

The total mass of cesium chloride, silver chloride, indium chloride, manganese chloride and disodium edetate is 0.7315g.

The indium chloride is 1 mmol.

The obtained Cs ₂ Na _0.2 Ag _0.8 InCl ₆ : 20% Mn perovskite long afterglow crystal was tested:

The crystal material obtained in the embodiment has the characteristics of ultraviolet absorption and can be excited by sunlight (see FIG. 2 ). After the excitation is stopped, there is a long red afterglow of more than one hour (see Figure 3), the synthetic yield is more than 70%, and it can be stored in a container with a cover for more than one year.

The synthesis temperature of the process of the invention is 180°C, which can effectively reduce industrial energy consumption and production cost, while the synthesis of other traditional long afterglow materials requires high-temperature calcination above 900°C.

The invention relates to solution method synthesis, avoids high-temperature sintering, can adjust the size and shape of crystals through surfactants, etc., and provides the possibility for the development of nano-scale long afterglow crystals.

The afterglow of the crystal involved in the present invention is pure red, and the spectrum does not drift with time (see FIG. 4 ).

The basic principles, main features and advantages of the present invention have been shown and described above. Those skilled in the industry should understand that the present invention is not limited by the above-mentioned embodiments, and what described in the above-mentioned embodiments and the description only illustrates the principles of the present invention, and the present invention will also have other functions without departing from the spirit and scope of the present invention. Variations and improvements all fall within the scope of the claimed invention. The protection scope of the present invention is defined by the appended claims and their equivalents.

Claims (7)

1. A low-temperature solution method synthesis process of a novel long-afterglow perovskite crystal is characterized by comprising the following steps:

1) In a stoichiometric ratio of Cs ₂ Na _X Ag _1-X InCl ₆ Putting cesium chloride, silver chloride, indium chloride, manganese chloride, ethylene diamine tetraacetic acid and concentrated hydrochloric acid into a polytetrafluoroethylene inner container, wherein X is more than or equal to 0.05 and less than or equal to 0.3, and Y is more than or equal to 0.05 and less than or equal to 0.3; then sealing the polytetrafluoroethylene inner container in a stainless steel autoclave;

2) Putting a stainless steel high-pressure autoclave into a muffle furnace, heating to 180 ℃ within 1h, keeping for 12h, slowly cooling the muffle furnace to 80 ℃ within 24-106 h, and finally naturally cooling to room temperature;

3) Opening the reaction kettle, discarding the upper liquid, placing the bottom crystal on absorbent paper, washing the single crystal for 3-5 times by using isopropanol, and adsorbing the isopropanol on the surface by using filter paper to obtain the perovskite long afterglow crystal.

2. The low-temperature solution synthesis process of a novel long-afterglow perovskite crystal according to claim 1, which is characterized in that: the concentrated hydrochloric acid in the step 1) is hydrochloric acid with the concentration of 36-38%.

3. The low-temperature solution synthesis process of a novel long-afterglow perovskite crystal as claimed in claim 1, which is characterized in that: the X is 0.2, the Y is 0.2, and the concentrated hydrochloric acid is 12mL.

4. The low-temperature solution synthesis process of a novel long-afterglow perovskite crystal as claimed in claim 1, which is characterized in that: the feeding ratio of manganese element contained in the manganese chloride to sodium element contained in the ethylene diamine tetraacetic acid is different, and the perovskite long afterglow crystals with different afterglow decay time can be obtained.

5. The low-temperature solution synthesis process of a novel long-afterglow perovskite crystal according to claim 1, which is characterized in that: the feed ratio of the manganese element contained in the manganese chloride to the sodium element contained in the ethylene diamine tetraacetic acid disodium is 6:1 to 36.

6. The low-temperature solution synthesis process of a novel long-afterglow perovskite crystal as claimed in claim 1, which is characterized in that: the mass of cesium chloride, silver chloride, indium chloride, manganese chloride and disodium ethylenediaminetetraacetate totaled 0.7315g.

7. The low-temperature solution synthesis process of a novel long-afterglow perovskite crystal as claimed in claim 1, which is characterized in that: the indium chloride is 1mmol.

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