Monodisperse carbon-containing ZrO2 microsphere structure color pigment, coating and preparation method of monodisperse carbon-containing ZrO2 microsphere structure color pigment

Abstract

The invention provides a monodisperse carbon-containing ZrO2 microsphere structure color pigment, a coating and a preparation method thereof, and belongs to the field of new materials. Monodisperse amorphous ZrO2 microspheres are controllably prepared by adopting a metal alkoxide hydrolysis method and regulating and controlling a hydrolysis kinetic process, and are subjected to heat treatment in an oxygen-deficient, inert or reducing atmosphere after being dried, so as to obtain the carbon-containing ZrO2 microsphere structural color pigment. The morphology of the microspheres is kept complete, the particle size is adjustable (150-700 nm), and the polydispersity index is low (PDilt; 0.05) of the method. The pigment is colored based on Mie scattering, has low angle dependence, and due to the uniform distribution of carbon and high color saturation, the color can be regulated and controlled through the particle size of the microspheres. The prepared structural color coating has the characteristics of ultraviolet radiation resistance, acid and alkali resistance and high-temperature resistance, can be used in the fields of high-temperature coatings, anti-counterfeiting marks, display, special material surface coloring and the like, and opens up a new way for application of the structural color pigment in an extreme environment.

Description

Technical Field

[0001] The present invention belongs to the field of new materials, and particularly relates to a monodisperse carbon-containing ZrO2 microsphere structural color pigment, a coating and a preparation method thereof. Background Art

[0002] Structural color results from the interference, diffraction, scattering and reflection of light by special micro-nano structures. Compared with traditional chemical dyes or pigments, it has the advantages of environmental protection and non-fading, and shows broad application prospects in the fields of display, anti-counterfeiting and encryption, optical sensing, decorative coatings, etc.

[0003] Preparing photonic crystals based on microsphere self-assembly is an important way to artificially generate structural color. Among them, inorganic microspheres with high refractive index and good stability have become ideal building blocks for constructing photonic crystals. However, structural color has strict requirements for the monodispersity and particle size range of microspheres (particle size deviation < 5%, and the size is between 150 and 700 nm). The controllable preparation of inorganic microspheres faces many challenges, resulting in limited types of microsphere materials and difficulty in meeting the application requirements of structural color in extreme or harsh environments. Therefore, developing new inorganic microsphere materials with strong weather resistance is of great significance for expanding the application space of structural color.

[0004] ZrO2 has a high refractive index, and also has the advantages of good thermal stability and high chemical inertness. It can remain stable in harsh environments such as high temperature and strong corrosion, and is an ideal material for constructing structural color. Although the synthesis research of ZrO2 microspheres has continued for many years, its applications are mainly concentrated in the fields of structural ceramics and catalyst carriers. The microspheres prepared by existing processes generally have a large particle size (> 1 μm) and a wide particle size distribution, and cannot meet the requirements for constructing photonic crystals. For example:

[0005] Chinese Patent Application CN 118833856 A prepared ZrO2 microspheres with a particle size of 1 - 500 μm by the microemulsion method. Chinese Patent Applications CN 111498900 A and CN 103288130 A respectively obtained ZrO2 microspheres with particle sizes of 4.9 - 1050 μm and 1.5 - 4 μm by the polymer template method. Chinese Patent ZL 01142023.5, Chinese Patent Applications CN 110862106 A and CN108147456 A all used zirconium oxychloride as the zirconium source and prepared ZrO2 microspheres with particle sizes of 1 - 10 μm, 2 - 4 μm and 0.3 - 2 μm (PDI is 0.214 - 0.637), respectively. Chinese Patent Application CN 110217818 A used potassium hexafluorozirconate as the zirconium source and prepared smaller-sized ZrO2 spheres (particle size 150 - 300 nm) by the hydrothermal method, but the sphericity was low and the particle size distribution was wide. All of the above do not meet the particle size requirements of structural color for monodisperse microspheres.

[0006] There are also some journal reports on the hydrolysis of metal alkoxides as zirconium sources, such as zirconium butoxide or zirconium propoxide, to prepare ZrO2 microspheres. Reports on the preparation of ZrO2 microspheres by the hydrolysis of zirconium propoxide are as follows: J. Sol-Gel Sci. Technol., 1997, 8, 207-211 (particle size 0.7-2.6 μm, particle size deviation 7%-23%); J. Am. Ceram. Soc., 2005, 88(3): 707-13 (particle size range 1.68-1.74 μm); J. Colloid Interface Sci., 2015, 448, 582–592 (range 0.8-4.2 μm, particle size deviation 5-10%). The ZrO2 microspheres prepared by the hydrolysis of zirconium butoxide also have relatively large sizes. For example: J. Am. Ceram. Soc, 1989, 12, 31, 421-26 (ZrO2 microspheres with a size of 1.62-1.18 μm, size standard deviation 10-22%); Cera. Intern., 1987, 13(1): 35-40. (average particle size 1.07 μm); Eur. J. Inorg. Chem. 2020, 4435–4441 (particle size about 0.8 μm).

[0007] Based on the above reports, it is still extremely difficult to synthesize monodisperse ZrO2 microspheres with controllable particle sizes that meet the requirements of structural color. This is closely related to the crystal growth kinetics characteristics and the limitations of conventional synthesis methods. The reason is that the synthesis of monodisperse microspheres requires precise regulation of reaction parameters, effective separation of the nucleation and particle aggregation growth processes, and inhibition of the generation of new aggregated microspheres during subsequent reactions. In actual reactions, crystal nucleation and growth often occur simultaneously, and the precursor concentration continuously changes during the reaction. Therefore, it is very difficult to achieve uniform particle size and precise regulation of microspheres.

[0008] So far, there has been no report on constructing structural color using monodisperse ZrO2 microspheres. A small amount of research on the structural color of ZrO2 materials is limited to ZrO2 thin films (Rare Met, 2023, 42, 3304–3310; ACS Appl. Mater. Interfaces, 2015, 7, 3641-3646) and inverse opal structures prepared using other microspheres as templates (Science of Sintering, 2020, 52, 299-306; Crystals, 2016, 6, 76). Their processes are complex and the color saturation is low, making it difficult to adapt to complex application scenarios such as display technologies. Summary of the Invention

[0009] Aiming at the deficiencies of the prior art, the present invention provides a monodisperse carbon-containing ZrO₂ microsphere structural color pigment and its preparation method. The main purpose is to solve the problems of too fast hydrolysis reaction rate of alkoxide and difficulty in precisely adjusting the particle size of microspheres by regulating the nucleation and aggregation growth kinetic processes of ZrO₂ microspheres, controllably prepare monodisperse ZrO₂ microspheres, and apply them to the field of structural color to expand the application space of structural color in extreme environments.

[0010] To achieve this purpose, the present invention adopts the following technical solutions:

[0011] Step 1: Weigh a certain amount of zirconium alkoxide, organic acid and absolute ethanol, and add them into sample bottles respectively. After stirring evenly at a certain temperature, obtain solution A for standby.

[0012] Step 2: Prepare an alcoholic solution of water. Add a certain amount of water into absolute ethanol, and add a certain amount of strong electrolyte salt as a charge regulator and a dispersant respectively, stir evenly, and heat to a certain temperature, denoted as solution B for standby.

[0013] Step 3: Prepare monodisperse amorphous ZrO₂ microspheres. At room temperature, take out solutions A and B respectively. Under continuous stirring, quickly pour solution A into solution B, continue to stir for a certain time, and then stand for aging at a certain temperature. After the obtained sample is centrifuged, washed with alcohol and dried, the obtained white product is monodisperse amorphous ZrO₂ microspheres.

[0014] Step 4: Prepare a carbon-containing ZrO₂ microsphere structural color pigment. Place the product obtained in Step 3 in a crucible, and heat-treat it in an oxygen-deficient, inert or reducing atmosphere at a certain temperature for 1 - 3 h, and naturally cool to room temperature. The obtained products of different colors are carbon-containing ZrO₂ microsphere structural color pigments.

[0015] Step 5: Preparation of a ZrO₂ microsphere structural color coating. Take a certain amount of the structural color pigment obtained in Step 4, grind it into powder, disperse it in deionized water, adjust the pH value of the dispersion, add a dispersant, and ultrasonically disperse it to form a stable structural color pigment dispersion. Take an appropriate amount of the dispersion and drop it on a substrate, and naturally dry it at room temperature to obtain a ZrO₂ microsphere structural color coating.

[0016] Step 6: Coating weather resistance test. Place the structural color coating in Step 5 at a high temperature for heat treatment for a certain time to test its thermal stability; prepare strong acid and strong base solutions with a certain concentration, immerse the structural color coating for a certain time to test its chemical stability; use an ultraviolet lamp box to test its anti-ultraviolet radiation performance.

[0017] Preferably, the zirconium source in Step 1 is zirconium n-butoxide, with a concentration of 0.05 - 0.1 g / mL; the organic acid is capric acid, with a concentration of 0.01 - 0.02 g / mL; the solvent is absolute ethanol; the temperature of solution A is 0 - 50 °C.

[0018] Preferably, in step 2, the electrolyte is an alkali metal chloride with a concentration of 0.1 - 0.3 M; the volume ratio of the zirconium source to water is 2:1 - 3:1; the temperature of solution B is 40 - 60 °C; the surfactant is PVP with a concentration of 1 - 2 mg / mL.

[0019] Preferably, in step 3, the stirring time is 60 - 1200 s, the aging temperature is 40 - 60 °C, and the aging time is 1 - 5 h.

[0020] Preferably, in step 4, the heat treatment temperature is 400 - 600 °C and the time is 2 - 5 h.

[0021] Preferably, in step 5, the dispersion medium is deionized water, the pH regulator is NaOH, the pH value is 9 - 11, the mass fraction of ZrO2 microspheres is 10 - 15%, and the mass fraction of ammonium polyacrylate is 0.05 - 0.1%.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. Carbon-containing ZrO2 microspheres with adjustable and uniform particle sizes (particle size 150 - 700 nm, PDI < 0.05) can be controllably prepared. The particle size parameters meet the requirements of structural color, and the refractive index reaches 1.85. Based on the principle of crystallization kinetics, the present invention precisely regulates the nucleation and aggregation processes of ZrO2 polycrystalline microspheres, effectively solving the problems of difficult precise regulation of particle size and uneven particle size distribution during the synthesis of ZrO2 microspheres. On this basis, by heat treatment, the organic matter in the system is in-situ carbonized, and carbon-containing ZrO2 microspheres with uniform size are successfully prepared.

[0024] 2. The present invention first uses monodisperse carbon-containing ZrO2 microspheres to construct structural color. Its color-forming mechanism is based on Mie scattering, without the need for long-range ordered structure, and the microsphere assembly is simple and easy. Uniformly distributed carbon can absorb stray light, thus significantly increasing the saturation of the structural color. In addition, the structural color pigment and coating have low-angle dependence, and their colors sequentially present various colors such as purple, blue, green, yellow, and brownish red as the microsphere size increases.

[0025] 3. The structural color of the carbon-containing ZrO2 microspheres prepared by the present invention has good thermal stability and chemical stability. After tests such as high temperature, ultraviolet aging, and strong acid and strong base corrosion, the structural color coating of ZrO2 microspheres does not show problems such as fading, color change, and dissolution, demonstrating stability under extreme conditions.

[0026] The monodisperse carbon-containing ZrO2 microsphere pigments and coatings developed by the present invention can be used in fields such as anti-counterfeiting, display, sensing, catalysis, and structural color decoration, which is of great significance for promoting the application of structural color in extreme environments such as high temperature, anti-ultraviolet, anti-acid and anti-base, and special occasions such as biomedicine. Description of the Drawings

[0027] Figure 1 It is the XRD pattern of Example 1.

[0028] Figure 2 They are the physical picture and reflection spectrum of Example 1.

[0029] Figure 3 They are the SEM and EDS pictures of Example 1.

[0030] Figure 4 They are the physical pictures of Examples 2 - 5.

[0031] Figure 5 They are the reflection spectra of Examples 2 - 5.

[0032] Figure 6 They are the SEM pictures of Examples 2 - 5.

[0033] Figure 7 They are the physical picture and reflection spectrum of Example 6

[0034] Figure 8 They are the physical pictures and reflection spectra of Example 7 before and after high - temperature treatment, ultraviolet aging, and strong acid / strong base corrosion. Detailed Implementation Modes

[0035] The following examples are used to illustrate the detailed implementation modes of the present invention. However, the following examples are only used to explain the present invention in detail and do not limit the scope of the present invention in any way.

[0036] Example 1:

[0037] Green sample

[0038] a. Prepare the precursor solution. At 2°C, a certain amount of capric acid and zirconium butoxide are added to anhydrous ethanol. The concentration of capric acid is 0.01 g / mL, and the concentration of zirconium butoxide is 0.07 g / mL. After stirring evenly, it is denoted as Solution A. Prepare a 0.1 M aqueous KCl solution. A certain amount of 0.1 M aqueous KCl solution and PVP are added to anhydrous ethanol, and it is denoted as Solution B. The volume ratio of the KCl aqueous solution to ethanol is 1:130, and the concentration of PVP is 1.25 mg / mL. Stir evenly and keep the temperature at 60°C.

[0039] b. Prepare monodisperse amorphous ZrO₂ microspheres. At room temperature, a certain amount of Solutions A and B (volume ratio A:B = 1:5) are taken respectively. Under continuous stirring, Solution A is quickly poured into Solution B. After 240 s, stop stirring and transfer the solution to an oven at 60°C for aging for 5 h.

[0040] c. The product was collected by centrifugation, washed three times with absolute ethanol, centrifuged again, and dried to obtain a solid powder. The obtained solid powder was placed in a crucible and heated in a muffle furnace at a heating rate of 3 °C / min to 500 °C, held for 3 h, and then naturally cooled to room temperature to obtain carbon-containing ZrO2 microspheres with an average particle size of 388 nm, which belonged to the tetragonal phase. The XRD was as shown in Figure 1 shown. The color of the sample was green, as shown in Figure 2 a. In its reflection spectrum, the two main peaks were located at 520 nm and 700 nm respectively, as shown in Figure 2 b. It could be seen from the SEM that the ZrO2 microspheres were regularly arranged, showing a face-centered cubic packing, and the size was about 388 nm, as shown in Figure 3 a; EDS showed that carbon was evenly distributed in it, as shown in Figure 3 b.

[0041] Example 2:

[0042] The difference from Example 1 was that in step a, when preparing solution B, the volume ratio of the KCl aqueous solution to ethanol was 1:110, and the remaining steps were the same as those in Example 1. The color of the sample was purple, as shown in Figure 4 a. In its reflection spectrum, the two main peaks were located at 460 nm and 620 nm respectively, as shown in Figure 5 a. It could be seen from the SEM that the ZrO2 microspheres were regularly arranged, showing a face-centered cubic packing, and the size was about 338 nm, as shown in Figure 6 a.

[0043] Example 3:

[0044] The difference from Example 1 was that in step c, the stirring time was 14 s and aging was not required, and the remaining steps were the same as those in Example 1. The color of the sample was blue, as shown in Figure 4 a. In its reflection spectrum, the two main peaks were located at 470 nm and 710 nm respectively, as shown in Figure 5 b. It could be seen from the SEM that the ZrO2 microspheres were regularly arranged, showing a face-centered cubic packing, and the size was about 253 nm, as shown in Figure 6 b.

[0045] Example 4:

[0046] The difference from Example 1 was that in step a, when preparing solution B, the volume ratio of the KCl aqueous solution to ethanol was 1:180, and the remaining steps were the same as those in Example 1. The color of the sample was yellow, as shown in Figure 4 a. In its reflection spectrum, the two main peaks were located at 490 nm and 660 nm respectively, as shown in Figure 5 c. In the SEM image, the ZrO2 microspheres were regularly arranged, showing a face-centered cubic packing, and the size was about 620 nm, as shown in Figure 6 c.

[0047] Example 5:

[0048] The difference from Example 1 is that in step a, when preparing solution B, the volume ratio of the KCl aqueous solution to ethanol is 1:200, and the remaining steps are the same as those in Example 1. The color of the sample is brownish red, as shown in Figure 4 Figure d. The two main peaks of its reflection spectrum are located at 520 nm and 640 nm respectively, as shown in Figure 5 Figure d. The SEM image shows that the size of ZrO2 is about 632 nm, the microspheres are arranged regularly, presenting face-centered cubic packing, as shown in Figure 6 Figure d.

[0049] Example 6:

[0050] a. Weigh an appropriate amount of the carbon-containing ZrO2 microspheres obtained in Example 1 (particle size about 388 nm), grind them thoroughly and disperse them in deionized water. Adjust the pH to 11 with NaOH, and then add ammonium polyacrylate and disperse it evenly by ultrasonic treatment. Among them, the mass fraction of ZrO2 microspheres is 15%, and the mass fraction of ammonium polyacrylate is 0.075%.

[0051] b. Measure 15 μL of the above dispersion liquid, drop it on a clean glass slide of 1.2×1.2 cm, and let the solvent evaporate at room temperature to obtain a green structural color coating. The physical picture is as shown in Figure 7 Figure a, and the reflection spectrum is as shown in Figure 7 Figure b.

[0052] Example 7:

[0053] a. The difference from Example 6 is that the particle size of ZrO2 microspheres is 362 nm, the amount of the dispersion liquid is 30 μL, and the substrate is a quartz of 2×2 cm. Figure 8 Figure a is a picture of the initial state of the structural color coating.

[0054] b. Place the ZrO2 microsphere structural color coating in a muffle furnace, heat it to 500 °C at a rate of 3 °C / min, keep it for 3 h, and the photo of the coating after natural cooling is as shown in Figure 8 Figure b.

[0055] c. Place the ZrO2 microsphere structural color coating in an ultraviolet aging chamber, the temperature is 40 °C, the ultraviolet light intensity at 365 nm is 1190 W / m 2 , and the ultraviolet aging time is 95 h. The picture of the structural color after ultraviolet aging is as shown in Figure 8 Figure c.

[0056] d. Prepare a 3M H2SO4 solution, immerse the ZrO2 microsphere structural color coating in the 3M H2SO4 solution for 24 h, and the picture of the structural color coating after strong acid corrosion is as shown in Figure 8 Figure d.

[0057] e. Prepare a 3M NaOH solution, immerse the ZrO₂ microsphere structural color coating in the 3M NaOH solution for 24 h. The picture of the structural color coating after strong alkali corrosion is shown as Figure 8 shown in e.

[0058] f. The reflection spectra of the coating before and after testing are shown as Figure 8 shown in f. After heat treatment, ultraviolet radiation, and immersion in strong acid / strong alkali, the ZrO₂ microsphere structural color coating did not show problems such as fading and color change, and the reflection spectrum did not change significantly.

[0059] In summary, the present invention discloses a preparation method of a monodisperse carbon-containing ZrO₂ microsphere structural color pigment. By using the metal alkoxide hydrolysis method and based on the principle of crystallization kinetics, the nucleation and aggregation growth processes are regulated to controllably prepare a series of monodisperse amorphous ZrO₂ microspheres with adjustable particle sizes and uniform sizes. In the subsequent heat treatment process, by using the decomposition of organic precursors, a carbon-containing ZrO₂ microsphere structural color pigment is obtained, and the surface charge amount of the carbon-containing ZrO₂ microspheres is further regulated to prepare a uniform structural color coating with good weather resistance. The synthesis method provided by the present invention is simple and easy to implement, has strong repeatability, effectively improves the monodispersity of ZrO₂ microspheres, and the lowest PDI can reach 0.017. Moreover, by regulating reaction parameters such as reaction time, temperature, and water dosage, the particle size can be conveniently adjusted. The particle size range of the carbon-containing ZrO₂ microspheres is 150-700 nm, and PDI < 0.05, meeting the color rendering requirements of structural colors. As the particle size of the microspheres increases, various colors such as purple, blue, green, yellow, and brownish red can be presented respectively. This structural color has characteristics such as low-angle dependence and high color saturation, and has broad application prospects in the fields of anti-counterfeiting, coatings, surface coloring of materials, and structural colors in extreme environments.

[0060] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, various changes and modifications can be made to the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A monodisperse carbon-containing ZrO2 microsphere structural color pigment, coating and preparation method thereof, characterized in that: The carbon-containing ZrO₂ microsphere structural color pigment has a microsphere size range of 150 - 700 nm, a PDI < 0.05, and the carbon is evenly distributed therein. The structural color has low-angle dependence and changes with the particle size, presenting purple, blue, green, orange, and red colors respectively. The coating can adhere to various substrates and maintain color stability under conditions such as high temperature, ultraviolet radiation, and strong acid and strong base corrosion.

2. The preparation method according to claim 1, characterized in that, Specifically, it includes the following steps: Step 1: Prepare the zirconium source solution. Weigh a certain amount of zirconium alkoxide, organic acid, and anhydrous ethanol, and add them to sample bottles respectively. After stirring evenly at a certain temperature, obtain solution A for standby. Step 2: Prepare the alcoholic solution of water. Dissolve a certain amount of water in ethanol, add a certain amount of strong electrolyte salt as a charge regulator and a small amount of dispersant respectively, stir evenly, and heat to a certain temperature, denoted as solution B for standby. Step 3: Prepare monodisperse amorphous ZrO₂ microspheres. At room temperature, take out solutions A and B respectively. Under continuous stirring, quickly pour solution A into solution B, continue stirring for a certain time, and then stand for aging at a certain temperature. After the obtained sample is centrifuged, washed with alcohol, and dried, the obtained white product is monodisperse amorphous ZrO₂ microspheres. Step 4: Prepare the carbon-containing ZrO₂ microsphere structural color pigment. Place the product obtained in Step 3 in a crucible and heat-treat it in an oxygen-deficient, inert, or reducing atmosphere at a certain temperature for 1 - 3 h, and then naturally cool to room temperature. The obtained products of different colors are the carbon-containing ZrO₂ microsphere structural color pigments. Step 5: Preparation of the ZrO₂ microsphere structural color coating. Take a certain amount of the structural color pigment obtained in Step 4, grind it into powder, disperse it in deionized water, adjust the pH value of the dispersion, add a dispersant, and after ultrasonic dispersion, form a stable structural color pigment dispersion. Take an appropriate amount of the dispersion and drop it on a substrate, and let it dry naturally at room temperature to obtain the ZrO₂ microsphere structural color coating. Step 6: Coating weather resistance test. Place the structural color coating in Step 5 under high temperature for heat treatment for a certain time to test its thermal stability; prepare strong acid and strong base solutions with a certain concentration, immerse the structural color coating for a certain time to test its chemical stability; Use an ultraviolet lamp box to test its anti-ultraviolet aging performance.

3. The method according to claim 1, characterized in that In Step 1, the zirconium source can be one or several of zirconium n-butoxide, zirconium n-propoxide, zirconium isopropoxide, zirconium ethoxide, and zirconium tert-butoxide. The zirconium source concentration in solution A is 0.01 - 0.5 g / mL. The solvents used can be one or several of anhydrous methanol, anhydrous ethanol, anhydrous propanol, anhydrous isopropanol, and anhydrous n-butanol. The organic acids used can be one or several of capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, and arachidic acid. The concentration is 0.001 - 0.05 g / mL. The temperature range of solution A is -10 - 70 °C.

4. The method according to claim 1, wherein In Step 2, the strong electrolyte is one or several of alkali metal halides, alkaline earth metal halides, nitrates, and sulfates, with a concentration of 0 - 1 M. The volume ratio of the zirconium source to water is 1:4 - 10:1; the temperature range of solution B is -10 - 70 °C. The surfactant used is one or more of sodium dodecyl sulfate, cetyltrimethylammonium bromide, polyethylene glycol, polyvinyl alcohol, polyvinylpyrrolidone (PVP), sorbitan fatty acid ester, cellulose and its derivatives, and the concentration is 0 to 10 mg / mL.

5. The method according to claim 1, wherein In step 3, the stirring time is 0 to 30 min; the aging temperature is 10 to 70 °C, and the time is 0 to 24 h.

6. The method according to claim 1, characterized in that, In step 4, the heat treatment temperature is 300 to 1000 °C, and the time is 1 to 5 h; the furnace used can be a tube furnace under the protection of inert and reducing gases (such as nitrogen, argon, hydrogen, etc.), or a muffle furnace in an oxygen-deficient environment.

7. The method according to claim 1, characterized in that In step 5, the mass fraction of the structural color pigment dispersion is: 1% to 40%; the dispersion medium can be one or more of water, methanol, ethanol, ethylene glycol, formamide, N,N-dimethylformamide, dimethyl sulfoxide; the pH regulator can be one or more of sodium hydroxide, potassium hydroxide, calcium hydroxide, ammonia water, hydrochloric acid, sulfuric acid, nitric acid, acetic acid; the pH value range is 3 to 14; the dispersant can be one or more of ammonium polyacrylate, polyethylene glycol, polyvinyl alcohol, polyvinylpyrrolidone, sorbitan fatty acid ester, cellulose and its derivatives; the mass fraction of the dispersant is 0 to 5%; the substrate can be glass, polymer, wood, ceramic or metal.

8. The method according to claim 1, characterized in that In step 6, the high temperature is 300 - 600 °C, and the time is 1 - 5 h; the strong acid is one or more of HCl, H2SO4, and HNO3, with a concentration of 3 - 5 M, and the soaking time is 24 - 48 h; the strong base is NaOH or KOH, with a concentration of 1 - 5 M, and the soaking time is 24 - 48 h; the ultraviolet light intensity is 1000 - 1500 W / m 2 , the radiation temperature is 30 - 50 °C, and the radiation duration is 50 - 200 h.

9. Use of the monodisperse carbon-containing ZrO2 microspheres and coatings according to claim 1, characterized in that, It is applied to fields such as anti-counterfeiting, display, sensing, catalysis, and structural color decoration, and is especially suitable for extreme harsh environments such as high temperature, ultraviolet resistance, acid and alkali resistance, or special occasions such as biomedicine.

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