阅读说明：本技术 一种多相复合钼酸盐氟氧化物纳米荧光材料的制备方法 (Preparation method of multiphase composite molybdate oxyfluoride nano fluorescent material ) 是由 彭玲玲 曹仕秀 强琴平 陈文波 韩涛 于 2020-12-03 设计创作，主要内容包括：一种多相复合钼酸盐氟氧化物纳米荧光材料K_3HF_2MoO_2F_4:Mn~(4+)的制备方法,具体是取(NH_4)_6Mo_7O_(24)·4H_2O和KHF_2溶解在质量浓度为40%的HF溶液中震荡至完全溶解形成溶液A,再将KMnO_4溶解在质量浓度为40%的HF酸溶液中震荡至完全溶解形成溶液B,将溶液A和溶液B混合后磁力搅拌20min,边搅拌边滴加无水乙醇,直至深紫色溶液褪色,逐渐形成粉色沉淀,且沉淀不再增加,停止搅拌,静置5~10min,过滤、洗涤,干燥。本发明制备的K_3HF_2MoO_2F_4:Mn~(4+)为十字交叉的片状结构,颗粒均匀,具有92%以上的量子产率,具有优异的发光性能,发光温度可达到90℃,在潮湿环境中具有优异的稳定性、L90值达到5500h以上,本发明采用的原料便宜、易得,制备方法简单,制备成本低,产率高,可有效应用于工业规模生产。(Multiphase composite molybdate oxyfluoride nano fluorescent material K 3 HF 2 MoO 2 F 4 :Mn 4+ The preparation method comprises the step of taking (NH) 4 ) 6 Mo 7 O 24 ·4H 2 O and KHF 2 Dissolving in 40% HF solution, shaking to dissolve completely to form solution A, and adding KMnO 4 Dissolving in HF acid solution with the mass concentration of 40%, shaking until the solution is completely dissolved to form solution B, mixing the solution A and the solution B, magnetically stirring for 20min, dropwise adding absolute ethyl alcohol while stirring until the dark purple solution fades to gradually form pink precipitate, stopping stirring until the precipitate is not increased, standing for 5-10 min, filteringWashing and drying. K prepared by the invention 3 HF 2 MoO 2 F 4 :Mn 4+ The material has a cross flaky structure, uniform particles, quantum yield of more than 92 percent, excellent luminescence property, luminescence temperature of 90 ℃, excellent stability in a humid environment, and L90 value of more than 5500 h.)

1. A preparation method of a multiphase composite molybdate oxyfluoride nano fluorescent material adopts a non-aqueous precipitation method for preparation, and is characterized in that: the multiphase composite molybdate oxyfluoride nano fluorescent material is K₃HF₂MoO₂F₄: Mn⁴⁺Specifically, taking (NH)₄)₆Mo₇O₂₄·4H₂O and KHF₂Dissolving in 40% HF solution, shaking to dissolve completely to form solution A, and adding KMnO₄Dissolving in an HF acid solution with the mass concentration of 40%, shaking until the solution is completely dissolved to form a solution B, mixing the solution A and the solution B, magnetically stirring for 20min, dropwise adding absolute ethyl alcohol while stirring until the dark purple solution fades to gradually form pink precipitates, stopping stirring until the precipitates are not increased any more, standing for 5-10 min, filtering, washing and drying.

2. The method for preparing the multiphase complex molybdate oxyfluoride nanometer fluorescent material as claimed in claim 1, wherein the method comprises the following steps: said (NH)₄)₆Mo₇O₂₄·4H₂O and KMnO₄The molar ratio of the used amount of the compound is 1: 0.05-0.2.

3. As claimed in claim 1 or2, the preparation method of the multiphase composite molybdate oxyfluoride nanometer fluorescent material is characterized by comprising the following steps: said (NH)₄)₆Mo₇O₂₄·4H₂O and KHF₂The molar weight ratio of K to Mo in the amount of (A) is 1: 3-11.

Technical Field

The invention relates to the technical field of luminescent materials, in particular to a preparation method of a multiphase composite molybdate oxyfluoride nano fluorescent material.

Background

Mn in recent years⁴⁺The red fluorescent powder doped with fluoride narrow-band emission has attracted wide attention due to the outstanding advantages of high luminous efficiency, good thermal stability, high color purity, capability of liquid phase synthesis and the like, and the spectral peak of the red fluorescent powder is narrower than that of commercial nitride red fluorescent powder, so that the red fluorescent powder has wide commercial prospect in the application of wide-color-gamut liquid crystal display backlight sources. However, the hygroscopicity problem is not solved, the stability is seriously influenced, and the application is limited, the research on the material is more and more due to the advantage of the stability of the oxyfluoride fluorescent powder at present, and the development of the red fluorescent material which has high stability and high color purity and can be effectively excited by near ultraviolet and blue light is very important.

Molybdate system fluorescent powder is mostly a self-activated luminescent material, has good thermal stability and chemical stability, narrow half-peak width of an emission peak, high color purity and low synthesis temperature, has strong absorption in near ultraviolet and blue light regions, and shows potential commercial prospect. The composite molybdate fluorescent powder is the fluorescent powder with improved luminescence performance by partially replacing cations or anions of a molybdate matrix and adjusting the coordination environment of a luminescence center lattice. For example, MoO₄ ^2-Quilt WO₄ ^2-、PO₄ ^3-、SO₄ ^2-、BO₃ ^3-Isosubstituted, isogroup elements such as Mg²⁺、Ca²⁺、Sr²⁺、Ba²⁺Etc. and Y³⁺、Gd³⁺、La³⁺Exchange of other elements, Mg²⁺、Ca²⁺With Zn²⁺The interchange of (c), etc.

Document "Red-Emitting K₃HF₂WO₂F₄:Mn⁴⁺for Application in Water-White Phosphor-Converted LEDs-Optical Properties and Magnetic research Characterization "reported the use of K₂MnF₆、KF、K₂MoO₄Preparing novel fluorescent powder K in HF solution by precipitation method₃HF₂MO₂F₄:Mn⁴⁺(M ═ Mo, W) comprises [ HF ═₂]^-And octahedra [ MO ]₂F₄]^2-The fluorescent powder material is a high-efficiency luminescent material, has nearly the same quantum yield under the substitution of low manganese, and stably exists for a long time in a humid environment. However, this document uses expensive K₂MnF₆(complicated preparation process, low yield and expensive selling price) and K₂MoO₄(Aladdin price 25.9/g) is used as raw material, and the specific method is mastered by German scientists, and in order to break through the technical monopoly, the same K needs to be prepared₃HF₂MO₂F₄:Mn⁴⁺A new approach to materials.

Disclosure of Invention

The invention aims to provide a preparation method of a multiphase composite molybdate oxyfluoride nano fluorescent material.

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

a preparation method of a multiphase composite molybdate oxyfluoride nano fluorescent material adopts a non-aqueous precipitation method for preparation, and is characterized in that: the multiphase composite molybdate oxyfluoride nano fluorescent material is K₃HF₂MoO₂F₄: Mn⁴⁺Specifically, taking (NH)₄)₆Mo₇O₂₄·4H₂O and KHF₂Dissolving in 40% HF solution, shaking to dissolve completely to form solution A, and adding KMnO₄Dissolving in 40% HF acid solution, shaking to dissolve completely to obtain solution B, mixing solution A and solution B, magnetically stirring for 20min, adding anhydrous ethanol dropwise while stirring, and standingAnd (3) fading the dark purple solution to gradually form pink precipitates, stopping stirring, standing for 5-10 min, filtering, washing and drying, wherein the precipitates are not increased any more.

K prepared by the invention₃HF₂MoO₂F₄:Mn⁴⁺The content ratio of the medium Mn element to the Mo element is 0.07at% to 10.8 at%.

The specific reaction process is as follows:

(NH₄)₆Mo₇O₂₄·4H₂O +KHF₂+ KMnO₄+HF→K₃HF₂MoO₂F₄:Mn⁴⁺。

in the present invention with (NH)₄)₆Mo₇O₂₄·4H₂O is molybdenum source and KMnO₄Is a source of manganese, potassium, KHF₂Is prepared from potassium source, fluorine source, HF solution as solvent, fluorine source and reducer, and absolute alcohol as precipitant through dissolving (NH)₄)₆Mo₇O₂₄·4H₂O、KHF₂Mixing and dissolving in HF, KMnO₄Separately dissolved in HF, and then mixed and stirred to react, and then precipitated by using absolute ethyl alcohol.

The prepared product is easy to have poor appearance, form indistinguishable agglomerates, have poor dispersibility and cannot form HF simultaneously₂]^-And [ MoO ]₂F₄]^2-And combined together to form a multiphase composite matrix, but formed as a single [ HF ]₂]^-Or [ MoO ]₂F₄]^2-Anions, or Mn forming a plurality of different matrices⁴⁺The phosphors are mixed together without forming a multi-phase complex K₃HF₂MoO₂F₄:Mn⁴⁺。

In the present invention, HF is used as KMnO₄The reducing agent of (1), KMnO is added in the reaction process₄Mn in (1)⁷⁺Reduction to Mn⁴⁺。

Further, the above (NH)₄)₆Mo₇O₂₄·4H₂O and KMnO₄The molar ratio of the used amount of the compound is 1: 0.05-0.2.

Further, the above (NH)₄)₆Mo₇O₂₄·4H₂O and KHF₂The molar weight ratio of K to Mo in the amount of (A) is 1: 3-11.

Due to K₃HF₂MoO₂F₄:Mn⁴⁺Is a fluorescent material which is easy to dissolve in water, therefore, the invention adopts HF as a solvent in the whole course, and adopts non-aqueous precipitation to reduce K₃HF₂MoO₂F₄:Mn⁴⁺Thereby increasing K₃HF₂MoO₂F₄:Mn⁴⁺The yield of (a).

The invention has the following technical effects:

k prepared by the invention₃HF₂MoO₂F₄:Mn⁴⁺The material is in a cross-shaped flaky structure, the particles are uniform, the quantum yield is more than 92%, the luminescent performance is excellent, the luminescent temperature can reach 90 ℃, the stability is excellent in a humid environment with the humidity of 80%, and the L90 value reaches more than 5200 h.

Drawings

FIG. 1: k prepared by the invention₃HF₂MO₂F₄:Mn⁴⁺XRD pattern of (a).

FIG. 2: k prepared by the invention₃HF₂MO₂F₄:Mn⁴⁺Scanning electron micrograph (c).

FIG. 3: k prepared by the invention₃HF₂MO₂F₄:Mn⁴⁺Excitation spectrum of (1).

FIG. 4: k prepared by the invention₃HF₂MO₂F₄:Mn⁴⁺The emission spectrum of (a).

Detailed Description

The present invention is described in detail below by way of examples, it should be noted that the following examples are only for illustrating the present invention and should not be construed as limiting the scope of the present invention, and those skilled in the art can make some insubstantial modifications and adaptations to the present invention based on the above-described disclosure.

Example 1

K₃HF₂MoO₂F₄:Mn⁴⁺The preparation method comprises the following steps:

to obtain (NH)₄)₆Mo₇O₂₄·4H₂O and KHF₂Dissolving in HF solution with mass concentration of 40% and shaking until completely dissolving to form solution A, (NH)₄)₆Mo₇O₂₄·4H₂O and KHF₂The molar weight ratio of K to Mo in the dosage of (1: 3), and then KMnO₄Dissolving in 40% HF acid solution, shaking to dissolve completely to form solution B, (NH)₄)₆Mo₇O₂₄·4H₂O and KMnO₄The molar ratio of the used amount of the solution A to the used amount of the solution B is 1:0.05, the solution A and the solution B are mixed and then are magnetically stirred for 20min, absolute ethyl alcohol is dropwise added while stirring until the dark purple solution fades, pink precipitates are gradually formed, the precipitates are not increased any more, the stirring is stopped, the solution is kept stand for 5min, supernatant liquid is poured out, the absolute ethyl alcohol is added, the precipitates are repeatedly washed for three times, then are filtered, and the solution is placed in a vacuum drying oven at 60 ℃ to be dried for 3 h.

Example 2

K₃HF₂MoO₂F₄:Mn⁴⁺The preparation method comprises the following steps:

to obtain (NH)₄)₆Mo₇O₂₄·4H₂O and KHF₂Dissolving in HF solution with mass concentration of 40% and shaking until completely dissolving to form solution A, (NH)₄)₆Mo₇O₂₄·4H₂O and KHF₂The molar weight ratio of K to Mo in the dosage of (1: 11), and then KMnO₄Dissolving in 40% HF acid solution, shaking to dissolve completely to form solution B, (NH)₄)₆Mo₇O₂₄·4H₂O and KMnO₄The molar ratio of the used amount of the solution A to the used amount of the solution B is 1: 0.2, and the solution A and the solution B are mixed and stirred by magnetic force for 20mAnd in, dropwise adding absolute ethyl alcohol while stirring until the dark purple solution fades, gradually forming pink precipitate, stopping stirring, standing for 10min, pouring out supernatant, adding absolute ethyl alcohol, repeatedly washing and precipitating for three times, performing suction filtration, and drying in a vacuum drying oven at 60 ℃ for 3 h.

Example 3

K₃HF₂MoO₂F₄:Mn⁴⁺The preparation method comprises the following steps:

to obtain (NH)₄)₆Mo₇O₂₄·4H₂O and KHF₂Dissolving in HF solution with mass concentration of 40% and shaking until completely dissolving to form solution A, (NH)₄)₆Mo₇O₂₄·4H₂O and KHF₂The molar weight ratio of K to Mo in the dosage of (1: 8), and then KMnO₄Dissolving in 40% HF acid solution, shaking to dissolve completely to form solution B, (NH)₄)₆Mo₇O₂₄·4H₂O and KMnO₄The molar ratio of the used amount of the solution A to the used amount of the solution B is 1:0.1, the solution A and the solution B are mixed and then are magnetically stirred for 20min, absolute ethyl alcohol is dropwise added while stirring until the dark purple solution fades, pink precipitates are gradually formed, the precipitates are not increased any more, the stirring is stopped, the solution is kept stand for 8min, supernatant liquid is poured out, the absolute ethyl alcohol is added, the precipitates are repeatedly washed for three times, then the suction filtration is carried out, and the solution is placed in a vacuum drying oven at 60 ℃ for drying for 3 h.

(NH) used in the present invention₄)₆Mo₇O₂₄·4H₂O is a molybdenum source (the purity is 99.9 percent, the price of the alatin is 3.25 yuan/g), and the price of the O and the raw materials is low and easy to obtain.

K cannot be prepared by various methods tried in the preparation process₃HF₂MoO₂F₄:Mn⁴⁺For example, KF is used instead of KHF₂When the potassium source and the fluorine source were reacted, they were found not to form K₃HF₂MoO₂F₄:Mn⁴⁺But directly form the KHF alone₂A phosphor as a matrix.

K prepared by the invention₃HF₂MoO₂F₄:Mn⁴⁺The XRD pattern of the phosphor is shown in FIG. 1, which shows that K is prepared by the invention₃HF₂MoO₂F₄:Mn⁴⁺A phosphor. K prepared by the invention₃HF₂MoO₂F₄:Mn⁴⁺The phosphor can be excited by near ultraviolet light-visible light, especially at about 475nm, has obvious red emission at 630nm, has a quantum rate of more than 92 percent, and has excellent luminescence property. L90 reached 5600h in dry environment, K was measured in an environment with 80% humidity₃HF₂MoO₂F₄:Mn⁴⁺It is known that the emission stability of the phosphor is 5200h or more in L90 (L90 means that the luminous flux of the phosphor is attenuated to 90% of the original luminous flux).