CN109158062B

CN109158062B - Silica colloid composite rare earth core-shell microspheres and preparation method thereof

Info

Publication number: CN109158062B
Application number: CN201811094377.2A
Authority: CN
Inventors: 龙泽荣; 冉文生; 沈仕林; 袁辉; 李漫江
Original assignee: Xinjiang Uygur Autonomous Region Product Quality Supervision and Inspection Research Institute
Current assignee: China Merchants Xinjiang Quality Inspection Technology Research Institute Co.,Ltd.
Priority date: 2018-09-19
Filing date: 2018-09-19
Publication date: 2021-08-03
Anticipated expiration: 2038-09-19
Also published as: CN109158062A

Abstract

本发明公开了一种二氧化硅胶体复合稀土核‑壳型微球的制备方法，其特征在于所述方法包括以下步骤：(1)纳米二氧化硅核的合成：将无水乙醇、正硅酸烷基酯、氨水和水按照体积比100:5‑15:5‑10:20‑30混合，得到纳米二氧化硅颗粒，洗涤至中性后，分散至无水乙醇中，得到纳米二氧化硅分散液，其浓度为0.2g/mL‑0.8g/mL；(2)采用浸渍‑水热法的稀土核‑壳型微球的合成：将至少两种稀土金属的水溶性盐混合，之后与步骤(1)的纳米二氧化硅分散液研磨直至产生颗粒状混合物，高温干燥，得到产物。本发明还涉及二氧化硅胶体复合稀土核‑壳型微球及其用途。

The invention discloses a preparation method of silica colloid composite rare earth core-shell microspheres, which is characterized in that the method comprises the following steps: (1) Synthesis of nano-silica cores: The acid alkyl ester, ammonia water and water are mixed according to the volume ratio of 100:5-15:5-10:20-30 to obtain nano-silicon dioxide particles, washed to neutrality, and dispersed into absolute ethanol to obtain nano-dioxide Silicon dispersion liquid, the concentration of which is 0.2g/mL-0.8g/mL; (2) Synthesis of rare earth core-shell microspheres by dipping-hydrothermal method: mixing at least two water-soluble salts of rare earth metals, and then Grinding with the nano-silica dispersion in step (1) until a granular mixture is produced, and drying at high temperature to obtain a product. The invention also relates to silica colloid composite rare earth core-shell microspheres and uses thereof.

Description

Silicon dioxide colloid composite rare earth core-shell microsphere and preparation method thereof

Technical Field

The invention relates to a silica colloid composite rare earth core-shell microsphere and a preparation method thereof.

Background

The colloidal rare earth fluorescent microsphere has wide application in photoelectric materials, drug delivery, heterogeneous catalysis, biological labeling and photochemical induction. Monodisperse silica colloidal spheres have a spherical configuration and a narrow size distribution, and are therefore very convenient to modify. The rare earth oxide is very expensive, so that the core-shell structure is formed by modifying a small amount of rare earth oxide on the surface of cheap silicon dioxide serving as a core, the use amount of rare earth is greatly reduced, and the material price is reduced. The composition, size and shell thickness of the core-shell structure can be controllably synthesized, so that the material is endowed with magnetism, mechanical property, thermodynamic stability, electrical property, photochemistry, catalytic property and the like, and the combination of functions and the improvement of performance can be realized according to the requirements of people. At present, the preparation method of loading rare earth on silica gel microspheres mainly comprises a sol-gel method, a coordination method, a homogeneous precipitation method and the like. The materials synthesized by the above methods all need to be carried out in solution, and thus there are problems of large amount of reagents, incomplete modification, time-consuming separation, and the like.

Therefore, there is still a need to develop new methods to meet the market demand.

Disclosure of Invention

The invention provides a preparation method of a silica colloid composite rare earth core-shell microsphere, which is characterized by comprising the following steps:

(1) and (3) synthesis of a nano silicon dioxide core: mixing anhydrous ethanol, alkyl orthosilicate (such as ethyl orthosilicate), ammonia water and water according to a volume ratio of 100:5-15:5-10:20-30 to obtain nano silicon dioxide particles, washing the nano silicon dioxide particles to be neutral, and dispersing the nano silicon dioxide particles into the anhydrous ethanol to obtain nano silicon dioxide dispersion liquid, wherein the concentration of the nano silicon dioxide dispersion liquid is 0.2g/mL-0.8g/mL, preferably 0.3g/mL-0.6g/mL, and more preferably 0.3g/mL-0.5 g/mL;

(2) the synthesis of the rare earth core-shell microsphere by adopting a dipping-hydrothermal method comprises the following steps: mixing water-soluble salts of at least two rare earth metals, dissolving the water-soluble salts in a small amount of water to the extent that the water-soluble salts are just completely dissolved, grinding the mixture with the nano silicon dioxide dispersion liquid in the step (1) until a granular mixture is generated, and drying the mixture at high temperature to obtain a product.

The invention also relates to a silica colloid composite rare earth core-shell microsphere prepared by the method; wherein the microspheres are made of SiO₂Nanoparticle cores and the SiO₂The surface of the core is coated with a layer of rare earth ion layer which is Gd formed by two rare earth elements ₂O₃:M³⁺Rare earth ionA layer, the rare earth element M being selected from one of: tb, Ru, Tb, Dy, Sm, Yb, Er, Ho or Eu, preferably Gd₂O₃:Eu ³⁺A rare earth ion layer.

The invention also relates to the application of the silica colloid composite rare earth core-shell microsphere in preparing a nano imprinted microsphere of a new identification and fluorescent quantitative pesticide.

The invention adopts the dipping-hydrothermal synthesis method to prepare the silicon dioxide composite rare earth core-shell type microsphere, and the synthesis method has the characteristics of simple operation, material saving, small environmental pollution, rapidness, no need of separation and clean product.

Drawings

FIG. 1Sol-gel method for preparing SiO₂@Gd₂O₃:Eu³⁺TEM analysis image of microspheres

FIG. 2 preparation of SiO by urea precipitation₂@Gd₂O₃:Eu³⁺TEM analysis of microspheres

FIG. 3 is SiO according to the present invention₂@Gd₂O₃:Eu³⁺TEM analysis image of microspheres

FIG. 4 shows SiO of the present invention₂@Gd₂O₃:Eu³⁺Infrared analysis map of microsphere

FIG. 5 shows SiO of the present invention₂@Gd₂O₃:Eu³⁺Fluorescence analysis of microspheres (e)_x257 nm; the sample was dispersed in absolute ethanol at a concentration of 0.15 mg/mL); the top right corner is the cathodoluminescence image of the sample powder.

Detailed Description

In one embodiment of the present invention, the absolute ethanol mass concentration is 95% and the ammonia water mass concentration is 25%.

In one embodiment of the invention, wherein one of the at least two rare earth metals is Gd, the at least one other metal M is selected from Gd, Eu, Tb, Y, Sm or Er.

In one embodiment of the invention, two rare earth metals are preferred, wherein the molar ratio of Gd to M is 4.5-4:1, preferably 4.2-4: 1.

In one embodiment of the invention, wherein the molar ratio of Gd to silica in the nanosilica dispersion is in the range of 1:20-60, preferably 1:25-50, more preferably 1: 25-35.

In one embodiment of the invention, the water-soluble salt of a rare earth metal is a chloride salt, a sulfate salt, a nitrate salt, preferably a nitrate salt.

In one embodiment of the present invention, wherein the grinding in step (2) is performed so that the raw material mixture is formed from emulsion → semi-paste → dough → granular; drying the obtained granular mixture at the temperature of 105-120 ℃ for more than 3 hours to obtain a product;

wherein the addition amount of water and the water-soluble salt of a rare earth metal in terms of moles and the drying temperature satisfy the following relational expression:

the addition amount of the water-soluble salt of the rare earth metal is more than or equal to 3.65 (T/298.15)/the addition amount of water is less than or equal to 5.05,

preferably 4.2. ltoreq. addition of water-soluble salts of rare earth metals (T/298.15)/water addition of 4.9 or less,

wherein T is the drying temperature in step (2), and is 400K-420K, preferably 408K-420K.

Without being bound by any theory, under the condition that the above relation is satisfied in the step (2), the clean silica colloid composite rare earth core-shell type microsphere without a separate separation step is obtained.

In one embodiment of the invention, the product of the invention is prepared as follows:

synthesis of SiO with uniform particle size₂Nanoparticles as the nanosilica core: adding 100.0mL of 95% ethanol, 5-15mL of 25% ammonia water and 20-30mL of high-purity water into a 250.0mL single-neck round-bottom flask, performing ultrasonic treatment for 5min, and magnetically stirring for 10min to uniformly mix the above solutions. Then 5-10mL of ethyl orthosilicate was added quickly. The mixture is magnetically stirred for 17 hours at 30 ℃ quickly and uniformly. And (3) centrifugally collecting the synthesized silicon dioxide, washing the product with absolute ethyl alcohol for multiple times, centrifuging until the supernatant centrifugate reaches neutrality, dispersing the silicon dioxide particles into the absolute ethyl alcohol to obtain nano silicon dioxide dispersion liquid with the concentration of 0.2g/mL-0.8g/mL, and placing the nano silicon dioxide dispersion liquid in a refrigerator at 4 ℃ for later use.

Adopting a dipping-hydrothermal method to synthesize the rare earth core-shell microsphere: mixing M (NO)₃)₃(e.g., Eu (NO)₃)₃·6H₂O and Gd (NO)₃)₃·6H₂Dissolving O in a small amount of distilled water, and fully shaking until the O is just dissolved. Adding the nano silicon dioxide dispersion liquid into an agate mortar for grinding, and after fully grinding, fully grinding the mixture to obtain a semi-paste mixture, wherein the mixture is in an emulsion state → a paste state → a dough state → a particle state, and when the mixture is in the emulsion state → the paste state, fully grinding is needed to uniformly mix the mixture, and then placing the mixture in a ventilated place until the mixture is semi-paste; when the paste is semi-pasty → dough, the paste is continuously and fully ground in the clockwise direction until the dough is shaped; dough → particles, the grinding step is to grind the sample to particles collectively, and finally the particle mixture is dried at high temperature, for example, 105 ℃ and 120 ℃, preferably 110 ℃ and 120 ℃ for more than 3 hours to obtain the product. For example, the granular mixture may be placed in an oven (where a glass dish containing KOH is placed in advance to absorb the NO and NO produced₂) And (5) drying.

The invention also relates to a silica colloid composite rare earth core-shell microsphere, wherein the microsphere is made of SiO₂Nanoparticle cores and the SiO₂A layer of rare earth ion layer coated on the surface of the core, wherein the rare earth ion layer is formed by two rare earth elementsGd of (2) ₂O₃:M³⁺A rare earth ion layer, the rare earth element M being selected from one of: tb, Ru, Tb, Dy, Sm, Yb, Er, Ho or Eu, preferably Gd₂O₃:Eu ³⁺。

The particle size of the microspheres is 50-80nm, preferably 60-75nm, which is more easily dispersed in a solution medium to form a stable microemulsion.

The invention also relates to the application of the silica colloid composite rare earth core-shell microsphere in preparing a nano-imprinted microsphere of a new identification and fluorescent quantitative pesticide, wherein the nano-imprinted microsphere is formed by forming a pesticide molecularly imprinted polymer layer on the microsphere.

In the present invention, unless otherwise specified, the operation is carried out under normal temperature and pressure conditions.

In the present invention, all parts and percentages are by mass unless otherwise specified.

In the present invention, the substances used are all known substances, and are commercially available or synthesized by known methods.

In the present invention, the apparatus or equipment used is conventional apparatus or equipment known in the art, and is commercially available.

The present invention will be described in detail with reference to examples, which are provided only for understanding the technical aspects of the present invention and are not intended to limit the scope of the present invention.

The instruments and reagents used in the present invention are as follows:

HYS-A cathodoluminescence apparatus (Hengyuan Huajiaoke, Beijing); ZEISS SUPRA 55VP transmission electron microscopy (German Zeiss); prestige-21 fourier transform infrared spectrometer (shimadzu, japan); model F4600 fluorescence spectrometer (HITACHI, japan).

Gd(NO₃)₃·6H₂O(≥95％)、M(NO₃)₃·6H₂O(≥95％)(M＝Eu³⁺、Tb³⁺、Y³⁺Sm³⁺Or Er³⁺) All purchased from Shanghai Merlin Biochemical reagent, Inc.; tetraethoxysilane (more than or equal to 95 percent) is purchased from Tianjin optical complex fine chemical research institute; KOH (more than or equal to 99 percent) purchased from Fuyu fine chemical industry in TianjinLimit company; anhydrous ethanol (AR) was purchased from Tianjin Baishi chemical Co. Distilled water was obtained from MiLi-Q pure water system, USA.

Examples

(1) Synthesizing a nano silicon dioxide core: 100.0mL of 95% ethanol, 6.0mL of 25% ammonia water, and 20.0mL of high purity water were added to a 250.0mL single-neck round-bottom flask, sonicated for 5min, and magnetically stirred for 10min to mix the above solutions uniformly. Then 8.0mL of ethyl orthosilicate was added quickly. Magnetic stirring was rapidly and uniformly carried out at 30 ℃ for 17 h. The synthesized silicon dioxide is collected by centrifugation, and the product is washed by absolute ethyl alcohol for many times and centrifuged. Dispersing the silicon dioxide particles into absolute ethyl alcohol until the upper layer centrifugate is neutral to obtain nano silicon dioxide dispersion liquid with the concentration of 0.3g/mL, and placing the nano silicon dioxide dispersion liquid in a refrigerator at the temperature of 4 ℃ for later use.

(2) Preparation of SiO by dipping-hydrothermal synthesis method₂Loaded Gd₂O₃:M(M＝Eu³⁺、Tb³⁺、Y³⁺Or Sm³⁺、Er³⁺) Microspheres

0.12mmol M(NO₃)₃(e.g., Eu (NO)₃)₃·6H₂O, 0.0535g) and 0.48mmol Gd (NO)₃)₃˙6H₂O (0.217g) was dissolved in 3mL of distilled water; adding nano silicon dioxide dispersion liquid containing 1.5g of silicon dioxide into an agate mortar, grinding, fully grinding, and taking about 3 hours for the whole process from a rice paste state to a dough state and finally to a granular state. Finally, the mortar was placed in a 110 ℃ oven and dried for 3h (in the oven, a glass dish containing KOH was placed in advance to absorb the NO and NO produced₂) And putting the mixture into a drying dish to cool the mixture to constant weight to obtain the silicon dioxide colloid composite rare earth core-shell microsphere with the particle size of about 70 nm.

Characterization of materials

TEM analysis

FIGS. 1-3 are transmission electron micrographs of products prepared by the sol-gel method, urea precipitation method and the immersion-hydrothermal synthesis method of the present invention, respectively.

For SiO synthesized by the experimental method of the invention₂-Gd₂O₃:Eu³⁺Materials and methods using prior art sol-gel methods (see in particularSee G.Z.Li, et al, Sol-gel contamination and phosphor properties of SiO₂@Gd₂O₃:Eu³⁺core-shell particles.J.Nanosci.Nanotechnol.,2006,6,1416-³⁺-doped SiO₂-Gd₂O₃prepared by the sol-gel process: Structural and optical properties.J.Sol-gel.Sci.Technol,2015,76,260-270) and urea precipitation (see in particular G.X.Liu, et al, Synthesis and characterization of SiO ₂/Gd₂O₃Eu core-shell luminescent materials J.Coll.Inter.Sci.,2004,278,133-138) synthesized₂-Gd₂O₃:Eu³⁺The material is subjected to Transmission Electron Microscope (TEM) morphology comparison. As shown in fig. 1-3, spherical structures are obtained with all three methods. In FIG. 1, the microspheres prepared by the sol-gel method (citric acid-polyethylene glycol) have strong adhesion phenomenon. FIG. 2 shows the preparation of urea by precipitation, but the product is washed with water and ethanol several times, and after centrifugation, white floc still appears in the centrifugate. The floccules can be observed in the electron microscope picture, and a part of Eu is probably supposed to be³⁺Conversion to Eu (OH)₃. FIG. 3 shows that the microspheres obtained by the experimental method of the present invention have good dispersibility, uniform particle size and very clean product.

IR analysis

FIG. 4 shows a diagram of a SiO solution prepared by the immersion-hydrothermal synthesis method of the present invention₂-Gd₂O₃:Eu³⁺IR spectrum of (a). As can be seen in FIG. 4, 3430cm^-1Stretching vibration of Si-OH groups on the surface of the material and-OH groups for absorbing water; 1097cm^-1Designated as antisymmetric stretching vibration of the Si-O-Si group, 802cm^-1Then it is the stretching vibration peak of the group. 540cm^-1The vicinity is usually designated as Gd-O bond because Gd and SiO₂The cores are bonded by chemical bonds.

3. Fluorescence analysis

FIG. 5 shows the preparation of SiO by the immersion-hydrothermal synthesis method of the present invention ₂-Gd₂O₃:Eu³⁺Fluorescence spectrum of (e)_x257 nm; the sample was dispersed in absolute ethanol at a concentration of 0.15 mg/mL); the upper right corner is as followsCathodoluminescence of the finished powder.

FIG. 5 shows the preparation of SiO by the immersion-hydrothermal synthesis method of the present invention₂-Gd₂O₃:Eu³⁺A fluorescence spectrum of (a). When the excitation wavelength is 257nm, the strongest emission peak is near 610nm, and the mark is Eu³⁺Is/are as follows⁵D₀→⁷F₂The transition peak of (2). This is Eu³⁺At Gd₂O₃Characteristic fluorescence in the lattice of the oxide matrix in the iso-cubic phase. The upper right corner of fig. 3 shows that the sample powder emits pink red fluorescence under excitation of Cathode Rays (CR).

Therefore, the SiO with good luminous performance is synthesized by the dipping-hydrothermal method₂-Gd₂O₃:Eu³⁺A fluorescent powder. TEM analysis shows that the synthesized sample has homogeneous grain size distribution, high dispersivity and very smooth surface and thus has core-shell structure. Fluorescence spectrum and cathode ray excitation spectrum show that the material has excellent fluorescence performance. Therefore, the silica colloid composite rare earth core-shell microsphere is used for preparing nano imprinting microspheres for new identification and fluorescent quantitative pesticides, such as carbamate pesticides, such as metolcarb, aldicarb, carbofuran, isoprocarb, pirimicarb, methomyl, and the like. Compared with the traditional sol-gel method and the precipitation method, the synthesis method has the characteristics of simple operation, material saving, small environmental pollution, no need of separation and clean product.

Claims

1.一种二氧化硅胶体复合稀土核-壳型微球的制备方法，其特征在于所述方法包括以下步骤：1. a preparation method of silica colloid composite rare earth core-shell microspheres, is characterized in that described method comprises the following steps:

(1)纳米二氧化硅核的合成：将无水乙醇、正硅酸烷基酯、氨水和水按照体积比100:5-15:5-10:20-30混合，得到纳米二氧化硅颗粒，洗涤至中性后，分散至无水乙醇中，得到纳米二氧化硅分散液，其浓度为0.2g/mL-0.8g/mL；(1) Synthesis of nano-silica core: mix absolute ethanol, alkyl orthosilicate, ammonia water and water in a volume ratio of 100:5-15:5-10:20-30 to obtain nano-silica particles , after washing to neutrality, disperse into absolute ethanol to obtain nano-silica dispersion liquid, and its concentration is 0.2g/mL-0.8g/mL;

(2)采用浸渍-水热法的稀土核-壳型微球的合成：将两种稀土金属的水溶性盐混合，并溶于少量水至其恰好溶解完的程度，之后与步骤(1)的纳米二氧化硅分散液研磨直至产生颗粒状混合物，高温干燥，得到产物；(2) Synthesis of Rare Earth Core-Shell Microspheres by Impregnation-Hydrothermal Method: Mix two water-soluble salts of rare earth metals, dissolve them in a small amount of water to the extent that they are just dissolved, and then perform the same procedure as in step (1) The nano-silicon dioxide dispersion is ground until a granular mixture is produced, and the product is dried at high temperature to obtain the product;

其中两种稀土金属中的一种为Gd，另一种金属M选自Eu、Tb、Y、Sm或Er。One of the two rare earth metals is Gd, and the other metal M is selected from Eu, Tb, Y, Sm or Er.

2.权利要求1所述的制备方法，其中无水乙醇质量浓度为95％，氨水质量浓度为25％。2. The preparation method of claim 1, wherein the absolute ethanol mass concentration is 95%, and the ammonia water mass concentration is 25%.

3.权利要求1所述的制备方法，其中正硅酸烷基酯为正硅酸乙酯。3. The preparation method of claim 1, wherein the alkyl orthosilicate is ethyl orthosilicate.

4.权利要求1所述的制备方法，其中纳米二氧化硅分散液浓度为0.3g/mL-0.6g/mL。4. The preparation method of claim 1, wherein the nano-silica dispersion concentration is 0.3g/mL-0.6g/mL.

5.权利要求4所述的制备方法，其中纳米二氧化硅分散液浓度为0.3g/mL-0.5g/mL。5. The preparation method of claim 4, wherein the nano-silica dispersion concentration is 0.3g/mL-0.5g/mL.

6.权利要求1所述的制备方法，其中两种稀土金属Gd与M的摩尔比为4.5-4:1。6. The preparation method of claim 1, wherein the molar ratio of the two rare earth metals Gd and M is 4.5-4:1.

7.权利要求6所述的制备方法，其中两种稀土金属Gd与M的摩尔比为4.2-4:1。7. The preparation method of claim 6, wherein the molar ratio of the two rare earth metals Gd and M is 4.2-4:1.

8.权利要求1所述的制备方法，其中Gd的水溶性盐与纳米二氧化硅分散液中的二氧化硅的摩尔比为1:20-60。8. The preparation method of claim 1, wherein the molar ratio of the water-soluble salt of Gd to the silicon dioxide in the nano-silica dispersion liquid is 1:20-60.

9.权利要求8所述的制备方法，其中Gd的水溶性盐与纳米二氧化硅分散液中的二氧化硅的摩尔比为1:25-35。9. The preparation method of claim 8, wherein the molar ratio of the water-soluble salt of Gd to the silicon dioxide in the nano-silica dispersion liquid is 1:25-35.

10.权利要求1所述的制备方法，其中稀土金属的水溶性盐为氯化物盐、硫酸盐、硝酸盐。10. The preparation method of claim 1, wherein the water-soluble salts of rare earth metals are chloride salts, sulfate salts, and nitrate salts.

11.权利要求1所述的制备方法，其中步骤(2)中的研磨,使得原料混合物由乳液状→半糊状→面团状→颗粒状；所得颗粒状混合物于105-120℃下干燥3小时以上，得到产物；11. The preparation method according to claim 1, wherein the grinding in step (2) makes the raw material mixture from emulsion → semi-paste → dough → granular; the obtained granular mixture is dried at 105-120° C. for 3 hours Above, the product is obtained;

其中以摩尔计的水和稀土金属的水溶性盐的加入量与干燥温度满足以下关系式：Wherein, the addition amount of water and the water-soluble salt of rare earth metal in moles and the drying temperature satisfy the following relational formula:

3.65≤稀土金属的水溶性盐的加入量*(T/298.15)/水的加入量≤5.05，3.65≤addition amount of water-soluble salt of rare earth metal*(T/298.15)/addition amount of water≤5.05,

其中T为步骤(2)中的干燥温度，其为403K-420K。Wherein T is the drying temperature in step (2), which is 403K-420K.

12.一种二氧化硅胶体复合稀土核-壳型微球，其由权利要求1-11任一项的方法制备；其中所述微球由SiO₂纳米颗粒核以及所述SiO₂核表面包覆的一层稀土离子层构成，所述稀土离子层为两种稀土元素形成的Gd₂O₃:M³⁺稀土离子层，所述稀土元素M选自以下的一种：Eu、Tb、Y、Sm或Er。12. A silica colloid composite rare earth core-shell microsphere, prepared by the method of any one of claims 1-11; wherein the microsphere is surrounded by a SiO ₂ nanoparticle core and a surface of the SiO ₂ core The rare earth ion layer is composed of a rare earth ion layer coated with a rare earth ion layer, and the rare earth ion layer is a Gd ₂ O ₃ :M ³⁺ rare earth ion layer formed by two rare earth elements, and the rare earth element M is selected from the following one: Eu, Tb, Y , Sm or Er.

13.权利要求12所述的二氧化硅胶体复合稀土核-壳型微球，其中Gd₂O₃:M³⁺稀土离子层为Gd₂O₃:Eu³⁺稀土离子层。13. The silica colloid composite rare earth core-shell microspheres according to claim 12, wherein the Gd ₂ O ₃ :M ³⁺ rare earth ion layer is a Gd ₂ O ₃ :Eu ³⁺ rare earth ion layer.

14.权利要求12所述的二氧化硅胶体复合稀土核-壳型微球，其中所述微球的粒径为50-80纳米。14. The silica colloid composite rare earth core-shell microspheres of claim 12, wherein the particle size of the microspheres is 50-80 nanometers.

15.权利要求12所述的二氧化硅胶体复合稀土核-壳型微球用作制备新识别和荧光定量农药的纳米印迹微球的用途。15. The use of the silica colloid composite rare earth core-shell microspheres of claim 12 as nano-imprinted microspheres for the preparation of new identification and fluorescence quantitative pesticides.