阅读说明：本技术 一种稀土近红外荧光粉及其制备方法及其应用 (Rare earth near-infrared fluorescent powder, and preparation method and application thereof ) 是由 王静 甘伟江 楼孙棋 曹鲁豫 于 2021-08-25 设计创作，主要内容包括：本发明公开了一种稀土近红外荧光粉及其制备方法和应用,属于发光材料技术领域。本发明的稀土近红外荧光粉化学式为：Cs-(2)AgIn-(1-x-)-(y)Sb-(x)Yb-(y)Cl-(6),其中,式中x,y分别为掺杂离子Sb～(3+),Yb～(3+)相对基质离子In～(3+)占的摩尔百分含量,取值范围：0.005≤x≤1.00,0.05≤y≤1.00,以无铅双钙钛矿Cs-(2)AgInCl-(6)作为基质材料,发光中心分别为三价Sb～(3+)和Yb～(3+)离子,在250～450nm近紫外光的激发下,三价Sb～(3+)离子在该基质中产生峰位位于670nm橘红光,Yb～(3+)离子产生峰位位于994nm近红外光,具有紫外至可见光区宽谱带激发和强近红外发射的优点,可广泛应用于近红外LED和硅基太阳能电池的光转换材料领域。(The invention discloses rare earth near-infrared fluorescent powder and a preparation method and application thereof, belonging to the technical field of luminescent materials. The rare earth near-infrared fluorescent powder has the chemical formula as follows: cs 2 AgIn 1‑x‑ y Sb x Yb y Cl 6 Wherein x and y are doped ions Sb respectively 3+ ，Yb 3+ Counter matrix ion In 3+ The weight percentage of the compound is as follows: x is more than or equal to 0.005 and less than or equal to 1.00, y is more than or equal to 0.05 and less than or equal to 1.00, and lead-free double perovskite Cs 2 AgInCl 6 As a host material, the luminescent centers are trivalent Sb respectively 3+ And Yb 3+ Ions, under the excitation of near ultraviolet light of 250-450 nm, trivalent Sb 3+ The ions generate orange light Yb with peak position at 670nm in the matrix 3+ The ion generation peak position is located in near infrared light of 994nm, has the advantages of broadband excitation and strong near infrared emission in the ultraviolet to visible light region, and can be widely applied to the field of light conversion materials of near infrared LEDs and silicon-based solar cells.)

1. The rare earth near-infrared fluorescent powder is characterized in that the chemical formula of the rare earth near-infrared fluorescent powder is as follows: cs₂AgIn_1-x-ySb_xYb_yCl₆Wherein x and y are doped ions Sb respectively³⁺，Yb³⁺Counter matrix ion In³⁺The weight percentage of the compound is as follows: x is more than or equal to 0.005 and less than or equal to 1.00, and y is more than or equal to 0.05 and less than or equal to 1.00.

2. The rare earth near-infrared phosphor of claim 1, wherein the rare earth near-infrared phosphor has a chemical formula of: cs₂AgIn_1-x-ySb_xYb_yCl₆Wherein x and y are doped ions Sb respectively³⁺，Yb³⁺Counter matrix ion In³⁺The weight percentage of the catalyst is that x is 0.01 and y is 0.2-0.8.

3. The rare earth near-infrared phosphor of claim 2, wherein the rare earth near-infrared phosphor has a chemical formula of: cs₂AgIn_1-x-ySb_xYb_yCl₆Wherein x and y are doped ions Sb respectively³⁺，Yb³⁺Counter matrix ion In³⁺The weight percentage of the catalyst is that x is 0.01 and y is 0.4-0.8.

4. The rare earth near-infrared phosphor of claim 1, wherein the rare earth near-infrared phosphor has a chemical formula of: cs₂AgIn_1-x-ySb_xYb_yCl₆Wherein x and y are doped ions Sb respectively³⁺，Yb³⁺Counter matrix ion In³⁺The content of x is 0.005-0.05, and y is 0.8.

5. A method for preparing the rare earth near-infrared phosphor of any one of claims 1 to 4, characterized by comprising the following steps:

s1, mixing an Ag-containing compound, an In-containing compound, an Sb-containing compound and a Yb-containing compound, adding hydrochloric acid with the mass concentration of 36-38%, and fully dissolving to form a mixed solution;

s2, adding a compound containing Cs into the mixed solution to initiate precipitation, continuing to react for 2-24h at 30-100 ℃, and purifying and drying to obtain the rare earth near-infrared fluorescent powder.

6. The method of claim 4, wherein the purification in S2 is ethanol washing purification.

7. Use of the rare earth near-infrared phosphor of any one of claims 1 to 3 in a near-infrared LED and a silicon-based solar cell.

8. The application of claim 7, wherein the rare earth near-infrared fluorescent powder is used as a light conversion material, and the excitation spectrum of the rare earth near-infrared fluorescent powder is 250-450 nm.

9. A near-infrared LED device, characterized in that the light conversion material of the near-infrared LED device is the rare earth near-infrared phosphor of any one of claims 1 to 4.

10. A silicon-based solar cell, characterized in that the light conversion material of the silicon-based solar cell is the rare earth near-infrared phosphor powder of any one of claims 1 to 4.

Technical Field

The invention relates to the technical field of luminescent materials, in particular to rare earth near-infrared fluorescent powder and a preparation method and application thereof.

Background

The near infrared light source has great application potential in the fields of photoelectron, food detection, anti-counterfeiting technology and biology due to invisibility and unique interaction with certain biomolecules, oil, water, sugar and the like, thereby attracting wide attention. At present, the application of the traditional halogen lamp with the near-infrared light source is hindered due to the defects of low luminous efficiency, high working temperature, long response time and the like, so that an efficient and sustainable near-infrared material for the light source is urgently needed. With the general application and development of LED technology, the light conversion near-infrared fluorescent powder material for the LED has adjustable fluorescence spectrum, high radiation flux, simple preparation method, low price and good durability, and is the current hot research direction.

In recent years, energy demand is increasing, and petrochemical energy resources are decreasing, so that people gradually look to renewable energy supply technology. Solar energy has the advantages of cleanness, environmental protection, no pollution, inexhaustibility, sustainable regeneration and the like, and is a potential novel clean energy for replacing the traditional energy, so that the solar photoelectric conversion technology is an important way for solving the energy problem, and the current silicon solar cell is the most mature and widely used. The most efficient place for a silicon solar cell to absorb solar energy is its band gap (E)_g1.12eV and lambda is approximately equal to 1000nm), and the solar spectral energy is mainly concentrated in the visible light region, so that the solar energy utilization efficiency is low, the thermal effect of the cell is severe, and finally the photoelectric conversion efficiency of the silicon-based solar cell is low, and the photoelectric energy conversion efficiency of the crystalline silicon-based solar cell industrially produced at present is only about 15%.

Among them, although rare earth doped lead-halogen perovskites have been widely reported to be used as potential near-infrared LEDs and solar energy light conversion layer materials, their further practical application is limited due to their poor stability to light, humidity, heat and other environments and their toxicity to lead. Lead-free perovskite materials have been the focus of research in recent years and made significant progress due to a series of unique optical properties, such as low toxicity and good material stability, compared to lead-halo perovskites. However, most of the lead-free perovskite materials emit light in the visible light region, so that the lead-free perovskite materials with high-efficiency near-infrared light emitting performance are extremely challenging.

CN107887466A discloses a rare earth doped inorganic perovskite quantum dot composite silicon solar cell and a preparation method thereof, the rare earth doped inorganic perovskite quantum dot composite silicon solar cell is composed of a silicon solar cell panel and a rare earth ion doped inorganic perovskite quantum dot film which is spin-coated or deposited on the light receiving surface of the silicon solar cell panel, and the doped ion in the inorganic perovskite is Yb³⁺、Ce³⁺、Sm³⁺、Tb³⁺、Eu³⁺、Dy³⁺、Nd³⁺、Gd³⁺、Er³⁺More than one of them, the inorganic perovskite quantum dots are CsPbCl_x1Br_y1I _z1Or Cs₂SnClx₂Bry₂Iz₂. Compared with the preparation method of the external and low-temperature reaction conditions, the preparation method of the rare earth doped inorganic perovskite quantum dot material needs inert atmosphere protection, high-temperature and other complex reaction conditions, and is not suitable for large-scale industrial preparation; and the composition of the material is not consistent with that of the rare earth near-infrared fluorescent powder material provided by the invention.

Disclosure of Invention

The invention aims to solve the technical problems that the existing rare earth near-infrared fluorescent powder light conversion material has weak absorption in the ultraviolet to visible light region and low light conversion efficiency for converting the rare earth near-infrared fluorescent powder into infrared light, and provides rare earth near-infrared fluorescent powder which is prepared by Sb³⁺，Yb³⁺Doping to lead-free double perovskite Cs₂AgInCl₆In (1), trivalent Sb is formed³⁺，Yb³⁺The ion luminescence center has wide absorption spectrum from ultraviolet to visible light, can realize stronger near-infrared emission, and provides a goodA different light conversion material.

The invention also aims to provide a preparation method of the rare earth near-infrared fluorescent powder

The invention further aims to provide application of the rare earth near-infrared fluorescent powder in a near-infrared LED and a silicon-based solar cell.

It is yet another object of the present invention to provide a near infrared LED device.

It is a further object of the present invention to provide a silicon-based solar cell.

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

a rare earth near-infrared fluorescent powder has a chemical formula as follows: cs₂AgIn_{1-x- y}Sb_xYb_yCl₆Wherein x and y are doped ions Sb respectively³⁺，Yb³⁺Counter matrix ion In³⁺The weight percentage of the compound is as follows: x is more than or equal to 0.005 and less than or equal to 1.00, and y is more than or equal to 0.05 and less than or equal to 1.00.

The substrate material of the rare earth near-infrared fluorescent material is lead-free double perovskite Cs₂AgInCl₆Since the lead-based perovskite has the structure of APbX₃(A ═ Cs/MA, etc., X ═ Cl/Br/I), lead ions are the constituent of the material, and one silver and one indium ion are used to replace two lead ions to form the matrix Cs₂AgInCl₆. The lead-based perovskite is easy to decompose under the external light, humidity and heat environment conditions, so that the performance is reduced, lead ions are dissociated, and the environment pollution is caused. The luminescent centers of the materials are trivalent Sb respectively³⁺，Yb³⁺Ions, under the excitation of near ultraviolet light of 250-450 nm, trivalent Sb³⁺The ions generate orange light Yb with peak position at 670nm in the matrix³⁺The ion generation peak position is located in near infrared light of 994nm, has the advantages of broadband excitation and strong near infrared emission in the ultraviolet to visible light region, and can be potentially applied to the field of light conversion materials of near infrared LEDs and silicon-based solar cells.

Yb is mainly used as rare earth light conversion material for silicon-based solar cells³⁺Ion infrared emission, whose emission is at about 1000nm, closely matches the forbidden band width of single crystal silicon, but Yb³⁺The ions have weak absorption in the ultraviolet to visible light region, and the rare earth near infrared fluorescent material has Sb³⁺Ion to Yb³⁺Due to the energy transfer of ions, the material can more effectively absorb ultraviolet and visible light within the range of 250-450 nm and convert the ultraviolet and visible light into infrared light with the wavelength of about 1000nm matched with a silicon-based solar cell, and has extremely high light conversion efficiency.

Preferably, the rare earth near-infrared phosphor has a chemical formula: cs₂AgIn_1-x-ySb_xYb_yCl₆Wherein x and y are doped ions Sb respectively³⁺，Yb³⁺Counter matrix ion In³⁺The weight percentage of the catalyst is that x is 0.01 and y is 0.2-0.8.

Further preferably, the rare earth near-infrared phosphor has a chemical formula: cs₂AgIn_1-x-ySb_xYb_yCl₆Wherein x and y are doped ions Sb respectively³⁺，Yb³⁺Counter matrix ion In³⁺The weight percentage of the catalyst is that x is 0.01 and y is 0.4-0.8.

Preferably, the rare earth near-infrared phosphor has a chemical formula: cs₂AgIn_1-x-ySb_xYb_yCl₆Wherein x and y are doped ions Sb respectively³⁺，Yb³⁺Counter matrix ion In³⁺The content of x is 0.005-0.05, and y is 0.8.

The invention also specifically protects a preparation method of the rare earth near-infrared fluorescent powder, which comprises the following steps:

s1, mixing an Ag-containing compound, an In-containing compound, an Sb-containing compound and a Yb-containing compound, adding hydrochloric acid with the mass concentration of 36-38%, and fully dissolving to form a mixed solution;

s2, adding a compound containing Cs into the mixed solution to initiate precipitation, continuing to react for 2-24 hours at the temperature of 30-100 ℃, and purifying and drying to obtain the rare earth near-infrared fluorescent powder.

Among them, it should be noted that:

the Ag-containing compound of the present invention may be: an oxide, carbonate, hydroxide, nitrate or chloride containing Ag, preferably a chloride containing Ag;

the In-containing compound of the present invention may be: an In-containing oxide, carbonate, hydroxide, nitrate or chloride, preferably an In-containing chloride;

the Sb-containing compound of the present invention may be: an oxide, carbonate, hydroxide, nitrate or chloride containing Sb, preferably a chloride containing Sb;

the Yb-containing compounds of the present invention may be: an Yb-containing oxide, carbonate, hydroxide, nitrate or chloride, preferably an Yb-containing chloride;

the Cs-containing compounds of the present invention may be: an oxide, carbonate, hydroxide, nitrate or chloride containing Cs, preferably a chloride containing Cs.

The compound is preferably chloride which can provide cations and anions required by the reaction, and can be better prepared into a pure phase.

And S2, reacting at 30-100 ℃ to generate nucleation growth and saturated recrystallization, wherein the reaction can be carried out at normal temperature, but the reaction temperature exceeds 100 ℃, and the high temperature can generate impurity phases to reduce the luminous intensity.

In the step S1, the full dissolution is performed by stirring and dissolving at 30-100 ℃, the compound containing Ag, In, Sb and Yb is dissolved by hydrochloric acid with the mass percentage concentration of 36-38%, and the 36-38% hydrochloric acid can be selected to better dissolve the precursor compound and provide the chloride ions required by the reaction.

The purification and drying step S2 is mainly to carry out solid-liquid separation on the product after the reaction, wash the solid product to remove the residual reactant after the reaction, and can use organic solvents with higher polarity such as methanol, ethanol, isopropanol, toluene and the like to wash the product, and then keep the temperature at 50-100 ℃ for 1-24 h until the product is completely dried, so as to obtain the purified rare earth near-infrared fluorescent powder material.

Preferably, the purification in S2 is an ethanol rinse purification.

Wherein the ethanol washing purification can be ethanol washing for 1-5 times.

The application of the rare earth near-infrared fluorescent powder in a near-infrared LED and a silicon-based solar cell is also within the protection scope of the invention.

Preferably, the rare earth near-infrared fluorescent powder is used as a light conversion material in the application, and the excitation spectrum of the rare earth near-infrared fluorescent powder is 250-450 nm.

The invention also specifically protects the near-infrared LED equipment, and the light conversion material of the near-infrared LED equipment is the rare earth near-infrared fluorescent powder.

The invention also specifically protects a silicon-based solar cell, and the light conversion material of the silicon-based solar cell is the rare earth near-infrared fluorescent powder.

Compared with the prior art, the invention has the beneficial effects that:

(1) the rare earth near-infrared fluorescent powder is a dual-emission fluorescent material, has a very wide excitation spectrum, can effectively absorb ultraviolet light and part of visible light within the range of 250-450 nm, and is suitable for the current commercial ultraviolet LED chips.

(2) The rare earth near-infrared fluorescent powder light conversion material has stronger near-infrared light emission, the main emission peak is 994nm, the energy of the light emission peak is matched with the forbidden bandwidth of silicon, the photoelectric conversion efficiency of a silicon-based solar cell can be effectively improved, and the rare earth near-infrared fluorescent powder light conversion material is a potential rare earth light conversion material for the silicon-based solar cell.

(3) The rare earth near-infrared fluorescent powder can reach 42.18% of quantum efficiency of absorption conversion of ultraviolet light and partial visible light.

(4) The preparation process method of the rare earth near-infrared fluorescent material is simple, easy to realize, low in cost and low in toxicity, and can be applied to large-scale industrialization.

Drawings

Figure 1 is the XRD patterns of examples 1, 2, 3, 4 and comparative examples 1, 2.

FIG. 2 is a graph of emission spectra of 1, 2, 3, 4 and comparative example 1.

FIG. 3 is a graph showing emission spectra of 4, 5, 6, 7 and comparative example 2.

Fig. 4 is an excitation and emission spectrum of the luminescent material of example 1.

Fig. 5 is an excitation and emission spectrum of the luminescent material of example 4.

Detailed Description

The present invention will be further described with reference to specific embodiments, but the present invention is not limited to the examples in any way. The starting reagents employed in the examples of the present invention are, unless otherwise specified, those that are conventionally purchased.

Example 1

A rare earth near-infrared fluorescent powder has a chemical formula as follows: cs₂AgIn_0.94Sb_0.01Yb_0.05Cl₆。

Cs₂AgIn_0.94Sb_0.01Yb_0.05Cl₆The preparation method of the fluorescent powder comprises the following steps:

s1, weighing 1mmol of silver chloride (AgCl) and 0.94mmol of indium chloride (InCl)₃) 0.01mmol of antimony chloride (SbCl)₃) 0.05mmol of ytterbium trichloride hexahydrate (YbCl)₃·6H₂O), the purity of the raw materials is more than 99.9%, the weighed raw materials are poured into a 10ml glass bottle, then 5ml of hydrochloric acid (36-38%) is added, the glass bottle is placed on a heating table, the constant temperature of 80 ℃ is kept for heating for 1 hour, and the raw materials are stirred to be dissolved;

s2, after the dissolution is finished, 2mmol of cesium chloride (CsCl) is added to initiate white precipitation, the constant temperature heating is continued for 2 hours, and the temperature is naturally reduced to the room temperature. And after the temperature is reduced to the room temperature, taking out the solid in the glass bottle, washing the solid for 3 times by using ethanol, putting the washed solid into an oven, and baking the solid for 8 hours at the temperature of 80 ℃ until the solid is completely dried to prepare the rare earth near-infrared fluorescent powder.

Example 2

A rare earth near-infrared fluorescent powder has a chemical formula as follows: cs₂AgIn_0.79Sb_0.01Yb_0.2Cl₆。

Cs₂AgIn_0.79Sb_0.01Yb_0.2Cl₆The preparation method of the fluorescent powder comprises the following steps:

s1, weighing 1mmol of silver chloride (AgCl) and 0.79mmol of indium chloride (InCl)₃) 0.01mmol of antimony chloride (SbCl)₃) 0.2mmol of ytterbium trichloride hexahydrate (YbCl)₃·6H₂O), the purity of the raw materials is more than 99.9%, the weighed raw materials are poured into a 10ml glass bottle, then 10ml hydrochloric acid (36-38%) is added, the glass bottle is placed on a heating table, the constant temperature of 80 ℃ is kept for heating for 1 hour, and the raw materials are stirred to be dissolved;

s2, after the dissolution is finished, 2mmol of cesium chloride (CsCl) is added to initiate white precipitation, the constant temperature heating is continued for 2 hours, and the temperature is naturally reduced to the room temperature. And after the temperature is reduced to the room temperature, taking out the solid in the glass bottle, washing the solid for 3 times by using ethanol, putting the washed solid into an oven, and baking the solid for 8 hours at the temperature of 80 ℃ until the solid is completely dried to prepare the rare earth near-infrared fluorescent powder.

Example 3

A rare earth near-infrared fluorescent powder has a chemical formula as follows: cs₂AgIn_0.59Sb_0.01Yb_0.40Cl₆。

Cs₂AgIn_0.59Sb_0.01Yb_0.40Cl₆The preparation method of the fluorescent powder comprises the following steps:

s1, weighing 1mmol of silver chloride (AgCl) and 0.59mmol of indium chloride (InCl)₃) 0.01mmol of antimony chloride (SbCl)₃) 0.4mmol of ytterbium trichloride hexahydrate (YbCl)₃·6H₂O), the purity of the raw materials is more than 99.9%, the weighed raw materials are poured into a 10ml glass bottle, then 10ml hydrochloric acid (36-38%) is added, the glass bottle is placed on a heating table, the constant temperature of 80 ℃ is kept for heating for 1 hour, and the raw materials are stirred to be dissolved;

s2, after the dissolution is finished, 2mmol of cesium chloride (CsCl) is added to initiate white precipitation, the constant temperature heating is continued for 2 hours, and the temperature is naturally reduced to the room temperature. And after the temperature is reduced to the room temperature, taking out the solid in the glass bottle, washing the solid for 3 times by using ethanol, putting the washed solid into an oven, and baking the solid for 8 hours at the temperature of 80 ℃ until the solid is completely dried to prepare the rare earth near-infrared fluorescent powder.

Example 4

A rare earth near-infrared fluorescent powder has a chemical formula as follows: cs₂AgIn_0.19Sb_0.01Yb_0.8Cl₆。

Cs₂AgIn_0.19Sb_0.01Yb_0.8Cl₆The preparation method of the fluorescent powder comprises the following steps:

s1, weighing 1mmol of silver chloride (AgCl) and 0.19mmol of indium chloride (InCl)₃) 0.01mmol of antimony chloride (SbCl)₃) 0.8mmol of ytterbium trichloride hexahydrate (YbCl)₃·6H₂O), the purity of the raw materials is more than 99.9%, the weighed raw materials are poured into a 10ml glass bottle, then 10ml hydrochloric acid (36-38%) is added, the glass bottle is placed on a heating table, the constant temperature of 80 ℃ is kept for heating for 1 hour, and the raw materials are stirred to be dissolved;

s2, after the dissolution is finished, 2mmol of cesium chloride (CsCl) is added to initiate white precipitation, the constant temperature heating is continued for 2 hours, and the temperature is naturally reduced to the room temperature. And after the temperature is reduced to the room temperature, taking out the solid in the glass bottle, washing the solid for 3 times by using ethanol, putting the washed solid into an oven, and baking the solid for 8 hours at the temperature of 80 ℃ until the solid is completely dried to prepare the rare earth near-infrared fluorescent powder.

Example 5

A rare earth near-infrared fluorescent powder has a chemical formula as follows: cs₂AgIn_0.195Sb_0.005Yb_0.8Cl₆。

Cs₂AgIn_0.195Sb_0.005Yb_0.8Cl₆The preparation method of the fluorescent powder comprises the following steps:

s1, weighing 1mmol of silver chloride (AgCl) and 0.195mmol of indium chloride (InCl)₃) 0.005mmol of antimony chloride (SbCl)₃) 0.8mmol of ytterbium trichloride hexahydrate (YbCl)₃·6H₂O), the purity of the raw materials is more than 99.9%, the weighed raw materials are poured into a 10ml glass bottle, then 5ml of hydrochloric acid (36-38%) is added, the glass bottle is placed on a heating table, the constant temperature of 80 ℃ is kept for heating for 1 hour, and the raw materials are stirred to be dissolved;

s2, after the dissolution is finished, 2mmol of cesium chloride (CsCl) is added to initiate white precipitation, the constant temperature heating is continued for 2 hours, and the temperature is naturally reduced to the room temperature. And after the temperature is reduced to the room temperature, taking out the solid in the glass bottle, washing the solid for 3 times by using ethanol, putting the washed solid into an oven, and baking the solid for 8 hours at the temperature of 80 ℃ until the solid is completely dried to prepare the rare earth near-infrared fluorescent powder.

Example 6

A rare earth near-infrared fluorescent powder has a chemical formula as follows: cs₂AgIn_0.17Sb_0.03Yb_0.8Cl₆。

Cs₂AgIn_0.17Sb_0.03Yb_0.8Cl₆The preparation method of the fluorescent powder comprises the following steps:

s1, weighing 1mmol of silver chloride (AgCl) and 0.17mmol of indium chloride (InCl)₃) 0.03mmol of antimony chloride (SbCl)₃) 0.8mmol of ytterbium trichloride hexahydrate (YbCl)₃·6H₂O), the purity of the raw materials is more than 99.9%, the weighed raw materials are poured into a 10ml glass bottle, then 5ml of hydrochloric acid (36-38%) is added, the glass bottle is placed on a heating table, the constant temperature of 80 ℃ is kept for heating for 1 hour, and the raw materials are stirred to be dissolved;

s2, after the dissolution is finished, 2mmol of cesium chloride (CsCl) is added to initiate white precipitation, the constant temperature heating is continued for 2 hours, and the temperature is naturally reduced to the room temperature. And after the temperature is reduced to the room temperature, taking out the solid in the glass bottle, washing the solid for 3 times by using ethanol, putting the washed solid into an oven, and baking the solid for 8 hours at the temperature of 80 ℃ until the solid is completely dried to prepare the rare earth near-infrared fluorescent powder.

Example 7

A rare earth near-infrared fluorescent powder has a chemical formula as follows: cs₂AgIn_0.15Sb_0.05Yb_0.8Cl₆。

Cs₂AgIn_0.15Sb_0.05Yb_0.8Cl₆The preparation method of the fluorescent powder comprises the following steps:

s1, weighing 1mmol of silver chloride (AgCl) and 0.15mmol of indium chloride (InCl) respectively₃) 0.05mmol of antimony chloride (SbCl)₃) 0.8mmol of ytterbium trichloride hexahydrate (YbCl)₃·6H₂O), the purity of the above raw materials are allPouring the weighed raw materials into a 10ml glass bottle at the concentration of more than 99.9 percent, then adding 5ml hydrochloric acid (36-38 percent), placing the glass bottle on a heating table, heating at the constant temperature of 80 ℃ for 1 hour, and stirring to be dissolved;

s2, after the dissolution is finished, 2mmol of cesium chloride (CsCl) is added to initiate white precipitation, the constant temperature heating is continued for 2 hours, and the temperature is naturally reduced to the room temperature. And after the temperature is reduced to the room temperature, taking out the solid in the glass bottle, washing the solid for 3 times by using ethanol, putting the washed solid into an oven, and baking the solid for 8 hours at the temperature of 80 ℃ until the solid is completely dried to prepare the rare earth near-infrared fluorescent powder.

Comparative example 1

Cs (volatile organic Compounds)₂AgInCl₆The preparation method of the fluorescent powder comprises the following steps:

1mmol of silver chloride (AgCl) and 1mmol of indium chloride (InCl) were weighed out separately₃) The purity of the raw materials is over 99.9 percent. The weighed raw materials are poured into a 10ml glass bottle, then 5ml hydrochloric acid (36-38%) is added, and the glass bottle is placed on a heating table to be heated for 1 hour at a constant temperature of 80 ℃ and stirred to be dissolved. After the dissolution is completed, 2mmol of cesium chloride (CsCl) is added to induce white precipitation, the mixture is continuously heated at the constant temperature for 2 hours, and the temperature is naturally reduced to the room temperature. After cooling to room temperature, the solid in the glass bottle was removed and rinsed 3 times with ethanol. The rinsed solid material was placed in an oven and baked at 80 ℃ for 8 hours to complete dryness.

Comparative example 2

Cs (volatile organic Compounds)₂AgIn_0.2Yb_0.8Cl₆The preparation method of the fluorescent powder comprises the following steps:

s1, weighing 1mmol of silver chloride (AgCl) and 0.2mmol of indium chloride (InCl)₃) 0.8mmol of ytterbium trichloride hexahydrate (YbCl)₃·6H₂O), the purity of the raw materials is more than 99.9%, the weighed raw materials are poured into a 10ml glass bottle, then 5ml of hydrochloric acid (36-38%) is added, the glass bottle is placed on a heating table, the constant temperature of 80 ℃ is kept for heating for 1 hour, and the raw materials are stirred to be dissolved;

s2, after the dissolution is finished, 2mmol of cesium chloride (CsCl) is added to initiate white precipitation, the constant temperature heating is continued for 2 hours, and the temperature is naturally reduced to the room temperature. And after the temperature is reduced to the room temperature, taking out the solid in the glass bottle, washing the solid for 3 times by using ethanol, and putting the washed solid into an oven to be baked for 8 hours at 80 ℃ until the solid is completely dried to prepare the fluorescent powder.

Result detection

FIG. 1 shows XRD patterns of examples 1-4 and comparative examples 1-2, and it can be seen from FIG. 1 that the rare earth infrared phosphor materials before and after doping of the invention have good consistency with the XRD diffraction pattern of ICSD standard card 244519, which indicates that the materials are pure phase.

FIG. 2 shows the emission spectra of examples 1-4 and comparative example 1. As can be seen from FIG. 2, the near infrared emission intensity of the rare earth near infrared phosphor of the present invention at 994nm is much higher than that of the matrix Cs₂AgInCl₆And (3) fluorescent powder.

FIG. 3 shows emission spectra of examples 4 to 7 and comparative example 2, and it can be seen from FIG. 3 that Sb according to the present invention³⁺,Yb³⁺The near-infrared emission intensity of the co-doped rare earth near-infrared fluorescent powder at 994nm is far higher than that of singly doped Yb³⁺And when x is 0.01 and y is 0.8, the luminescence of the sample is strongest.

FIG. 4 shows the excitation and emission spectra of the luminescent material of example 1, and it can be seen from FIG. 4 that the obtained rare earth near-infrared phosphor has near-infrared emission at 994nm, and the excitation spectrum shows broadband absorption from 250nm to 450nm, indicating that the material can meet the requirements of near-ultraviolet excitation.

FIG. 5 shows the excitation and emission spectra of the luminescent material of example 4. from FIG. 5, the obtained rare earth near-infrared phosphor has near-infrared emission at 994nm, and the excitation spectrum shows broadband absorption from 250nm to 450nm, indicating that the material can meet the requirements of near-ultraviolet excitation.

The near infrared luminous efficiency detection is to carry out luminous intensity correction and luminous efficiency test by an Edinburgh transient steady state fluorescence (FLS1000) spectrometer.

The luminescence quantum efficiency values of the examples and the comparative examples were measured, and the specific measurement results are shown in table 1 below:

TABLE 1

As can be seen from the data in Table 1, the codoped Sb of the present invention³⁺，Yb³⁺The ionic rare earth near-infrared fluorescent powder has stronger near-infrared light emission, the near-infrared light emission intensity can reach 3696254.22(a.u.), the near-infrared light emission efficiency can reach 42.18 percent, and the Cs in the comparative example 1₂AgInCl₆Phosphor and comparative example 2 doped only Yb³⁺The fluorescent powder can not reach the near-infrared luminous intensity of the invention, and the near-infrared luminous efficiency is quite weak.

It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.