Bismuth oxybromide / aluminum oxide composite functional ceramic and preparation method thereof

Abstract

The invention belongs to the technical field of porous material synthesis and inorganic nonmetal-based composite material preparation, and particularly relates to bismuth oxybromide / aluminum oxide composite functional ceramic and a preparation method thereof. The bismuth oxybromide / aluminum oxide composite functional ceramic is obtained by taking porous aluminum oxide ceramic as a carrier and carrying bismuth oxybromide micro / nano powder through secondary low-temperature sintering. Through multi-material and multi-scale compounding, the coupling of adsorbability and photocatalysis is realized, so that the continuous and dynamic purification of sewage is met, for example, the direct degradation rate to rhodamine B under the water flow velocity of 0.1 mm / s reaches 71% or above, and the highest direct degradation rate can reach 96%. The bismuth oxybromide / aluminum oxide composite functional ceramic does not need to be dissolved in sewage, dynamic and continuous catalytic degradation of the sewage can be realized when the sewage flows through the bismuth oxybromide / aluminum oxide composite functional ceramic, and the bismuth oxybromide / aluminum oxide composite functional ceramic is environment-friendly.

Description

Technical Field

[0001] The present invention belongs to the technical field of synthesis of porous materials and preparation of inorganic non-metallic matrix composites, and particularly relates to a bismuth oxybromide / aluminum oxide composite functional ceramic and a preparation method thereof. Background Art

[0002] Traditional nano-photocatalysts have advantages such as a large specific surface area, strong adsorption, and high catalytic activity. In particular, bismuth oxybromide (Bi x O y Br z ) is an excellent semiconductor material due to its special layered structure, non-toxicity, high stability, and easy adjustment of band gap width. However, it is easily deactivated by external environmental pollution, resulting in a short service life.

[0003] Based on this, in the prior art, composite bismuth oxyhalide catalysts have been developed. For example, in the Chinese invention patent CN202310946355.9, a catalyst with a composite bismuth oxyhalide catalyst loaded with active metal components was prepared. The degradation rate of the dye Rhodamine B was 60% to 71% in 30 minutes, and the degradation rate of the dye Rhodamine B could only reach more than 90% in 60 minutes. It takes a long time to degrade pollutants to achieve better effects, and it cannot perform instant degradation and cannot purify sewage under continuous flow conditions. Summary of the Invention

[0004] Based on this, the present application provides a bismuth oxybromide / aluminum oxide composite functional ceramic and a preparation method thereof to solve the technical problems in the prior art that the composite bismuth oxyhalide catalyst takes a long time to degrade pollutants to achieve better effects, cannot perform instant degradation, and cannot purify sewage under continuous flow conditions.

[0005] The technical solution of the present application to solve the above technical problems is as follows:

[0006] A preparation method of a bismuth oxybromide / aluminum oxide composite functional ceramic material, comprising the following steps:

[0007] S10. Add a binder, an open pore forming agent, and a plasticizing auxiliary agent to deionized water, and mix evenly to obtain a mixed suspension A;

[0008] S20. Mix the mixed suspension A with grinding balls and aluminum oxide powder, and ball mill to obtain a ceramic slurry B;

[0009] S30. After the ceramic slurry B is frozen and solidified, vacuum dry to obtain a ceramic green body, and then sinter the ceramic green body and naturally cool it to obtain an aluminum oxide porous ceramic;

[0010] S40. Disperse bismuth oxybromide into deionized water to obtain a bismuth oxybromide suspension C with a concentration of 10 to 40 mg / l for standby.

[0011] S50. Uniformly coat the bismuth oxybromide suspension C on the surface of the porous alumina ceramic. After drying, a bismuth oxybromide / alumina composite ceramic green body is obtained.

[0012] S60. Under an inert atmosphere, secondarily sinter the bismuth oxybromide / alumina ceramic green body to obtain the bismuth oxybromide / alumina composite functional ceramic material.

[0013] Preferably, in the preparation method of the above bismuth oxybromide / alumina composite functional ceramic material, in step S10, the addition ratio of the binder, open pore forming agent, plasticizing aid and deionized water is (0.1 g to 0.25 g):(0.8 g to 3.0 g):(0.75 ml to 1.7 ml):(13 ml to 17 ml).

[0014] Preferably, in the preparation method of the above bismuth oxybromide / alumina composite functional ceramic material, in step S10, the binder includes at least one of polyvinyl alcohol, sodium carboxymethyl cellulose, and polyacrylamide.

[0015] Preferably, in the preparation method of the above bismuth oxybromide / alumina composite functional ceramic material, in step S10, the open pore forming agent includes at least one of starch, sawdust, rice husk, and carbon powder.

[0016] Preferably, in the preparation method of the above bismuth oxybromide / alumina composite functional ceramic material, in step S10, the plasticizing aid includes at least one of glycerol, polyethylene glycol, and hydroxyethyl methyl cellulose.

[0017] Preferably, in the preparation method of the above bismuth oxybromide / alumina composite functional ceramic material, in step S20, the addition ratio of the mixed suspension A, grinding balls and alumina powder is (14 ml to 20 ml):(25 g to 45 g):(14.5 g to 24.5 g).

[0018] Preferably, in the preparation method of the above bismuth oxybromide / alumina composite functional ceramic material, in step S30, the sintering temperature is 1100 to 1600 °C, and the sintering time ≥ 1 h.

[0019] Preferably, in the preparation method of the above bismuth oxybromide / alumina composite functional ceramic material, in step S30, the freezing and curing temperature is below -10 °C, and the vacuum drying temperature is -30 to 5 °C.

[0020] Preferably, in the preparation method of the above-mentioned bismuth oxybromide / aluminum oxide composite functional ceramic material, in step S60, the secondary sintering temperature is 400 to 580 °C, and the secondary sintering time is 1 ± 0.5 h.

[0021] A bismuth oxybromide / aluminum oxide composite functional ceramic material is prepared by using the preparation method of the bismuth oxybromide / aluminum oxide composite functional ceramic material described in any one of the above.

[0022] Compared with the prior art, the present application has at least the following advantages:

[0023] (1) The present invention prepares porous alumina ceramics by using an open pore forming agent-assisted freeze-drying method. The porous ceramics have the characteristics of layered through holes, closed pores and open pores. The layered through holes formed by freeze-drying enable liquids to effectively flow from top to bottom; during the sintering process, the open pore forming agent volatilizes to provide open pores for the porous ceramics, providing sites for the loading of functional micro / nano photocatalysts.

[0024] (2) The porous ceramics prepared by the present invention have a uniform microstructure, high compressive strength, large specific surface area, excellent chemical stability, high-temperature stability, mechanical strength and adsorption, and the preparation process has almost "zero" pollution to the environment.

[0025] (3) The present invention selects alumina porous ceramics as the carrier and loads bismuth oxybromide micro / nano powder to prepare a bismuth oxybromide / aluminum oxide composite functional ceramic capable of sewage purification under continuous flow conditions. The preferred bismuth oxybromide / aluminum oxide composite functional ceramic has a direct degradation rate of rhodamine B of more than 71%, an average of 82%, and a maximum of 96% under continuous flow conditions. Description of the Drawings

[0026] Figure 1 It is a schematic diagram, a top view and a side view of the bismuth oxybromide / aluminum oxide composite functional ceramic prepared in Example 2 of the present invention, where: (a) schematic diagram, (b) side view, (c) top view.

[0027] Figure 2 It is the direct purification effect of the bismuth oxybromide / aluminum oxide composite functional ceramic prepared by the present invention on rhodamine B at a flow rate of 0.1 mm / s.

[0028] Figure 3 It is the XRD pattern of the bismuth oxybromide / aluminum oxide composite functional ceramic prepared by the present invention. Detailed Embodiments

[0029] To facilitate the understanding of this application, the following will provide a more comprehensive description of this application with reference to the relevant attached drawings. The preferred embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of this application more thorough and comprehensive.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this application belongs. The terms used in the description herein are for the purpose of describing specific embodiments only and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0031] In a specific embodiment of this application, please refer to Figures 1 to 3 In a specific embodiment of this application,

[0032] A preparation method of a bismuth oxybromide / aluminum oxide composite functional ceramic material, comprising the following steps:

[0033] S10. Add a binder, an open pore forming agent, and a plasticizing aid to deionized water, mix evenly to obtain a mixed suspension A;

[0034] In one embodiment, the addition ratio of the binder, the open pore forming agent, the plasticizing aid to deionized water is (0.1 g to 0.25 g):(0.8 g to 3.0 g):(0.75 ml to 1.7 ml):(13 ml to 17 ml).

[0035] In one embodiment, the binder includes at least one of polyvinyl alcohol, sodium carboxymethyl cellulose, and polyacrylamide. In this application, polyvinyl alcohol is preferably used. In addition to acting as a binder to enhance the strength of the green body and improve the dispersion of the powder, polyvinyl alcohol also has the function of a plasticizing aid, playing a role in improving plasticity, reducing internal stress, and regulating the rheological properties of the slurry.

[0036] Further, the open pore forming agent includes at least one of starch, sawdust, rice husk, and carbon powder. As a natural polymer, starch will be decomposed or eluted during high-temperature treatment or hydrolysis, thereby forming pores in the material. Therefore, the pore forming agent in this application is preferably starch.

[0037] The plasticizing aid includes at least one of glycerol, polyethylene glycol, and hydroxyethyl methyl cellulose.

[0038] S20. Mix the mixed suspension A with grinding balls and aluminum oxide powder, and ball mill to obtain a ceramic slurry B;

[0039] In one embodiment, the addition ratio of the mixed suspension A, grinding balls and alumina powder is (14 ml to 20 ml):(25 g to 45 g):(14.5 g to 24.5 g). In this application, the D50 characteristic value of the alumina powder is 500 nm, and the diameter d of the grinding balls is 1 cm.

[0040] Specifically, pour 14 ml to 20 ml of the mixed suspension A into a ball mill tank containing 25 to 45 g of grinding balls and 10.5 to 24.5 g of alumina powder, and ball mill for 3 to 5 h to obtain a ceramic slurry B with the solid and liquid phases fully and evenly mixed.

[0041] S30. After freeze-curing the ceramic slurry B, perform vacuum drying to obtain a ceramic green body, and then sinter the ceramic green body and naturally cool it to obtain alumina porous ceramics; in a preferred embodiment, the sintering temperature is 1100 to 1600 °C, and the sintering time is ≥1 h. Further, the freeze-curing temperature is below -10 °C, and the vacuum drying temperature is -30 to 5 °C.

[0042] For example, pour the evenly mixed ceramic slurry B into a PVC mold, freeze-cure it below -10 °C, then perform vacuum drying at -30 to 5 °C to obtain a ceramic green body, and then sinter the ceramic green body at 1100 to 1600 °C for ≥1 h and naturally cool it to obtain alumina porous ceramics.

[0043] S40. Disperse bismuth oxybromide into deionized water to obtain a bismuth oxybromide suspension C with a concentration of 10 to 40 mg / l for standby;

[0044] S50. Uniformly coat the bismuth oxybromide suspension C on the surface of the alumina porous ceramics, and after drying, obtain a bismuth oxybromide / alumina composite ceramic green body;

[0045] S60. Under an inert atmosphere, secondarily sinter the bismuth oxybromide / alumina ceramic green body to obtain the bismuth oxybromide / alumina composite functional ceramic material.

[0046] The inert gas can be, for example, N2, Ar, etc. In a preferred embodiment, the secondary sintering temperature is 400 to 580 °C, and the secondary sintering time is 1 ± 0.5 h.

[0047] For example, uniformly coat the bismuth oxybromide suspension C on the surface of the alumina porous ceramics, dry it at 20 to 70 °C to obtain a bismuth oxybromide / alumina ceramic green body. Then, under an inert gas atmosphere, sinter the bismuth oxybromide / alumina ceramic green body at 400 to 580 °C for 1 ± 0.5 h to obtain the bismuth oxybromide / alumina composite functional ceramic material. Please refer to Figure 1 , the schematic diagram, top view, and side view of the bismuth oxybromide / alumina composite functional ceramic prepared by the present invention.

[0048] The present invention uses porous alumina ceramics as a carrier, and loads bismuth oxybromide micro / nano powders by secondary low-temperature sintering to obtain a bismuth oxybromide / alumina composite functional ceramic. Through the multi-material and multi-scale composite, the coupling of adsorption and photocatalysis is realized, so as to meet the continuous and dynamic purification of sewage. For example, the direct degradation rate of Rhodamine B reaches more than 71% at a water flow rate of 0.1 mm / s, and can reach up to 96%. And compared with traditional catalysts that need to be dissolved in sewage (liquid to be treated) for catalytic degradation, the catalyst may be difficult to remove in water, causing certain potential environmental pollution hazards. The bismuth oxybromide / alumina composite functional ceramic of the present invention does not need to be dissolved in sewage, and the sewage can achieve dynamic and continuous catalytic degradation when flowing through and permeating the bismuth oxybromide / alumina composite functional ceramic, which is environmentally friendly.

[0049] In another specific embodiment of the present application, a bismuth oxybromide / alumina composite functional ceramic material is prepared by using the preparation method of the bismuth oxybromide / alumina composite functional ceramic material described in any one of the above.

[0050] It should be noted that the process temperature and process time involved in the above embodiments are both a temperature or time adopted in the experimental process. Those skilled in the art can make reasonable adjustments within the error range based on the process temperature and process time provided by the present invention, and should be included in the protection scope of the present invention; the binder, open pore forming agent, and plasticizing auxiliary agent are preferred embodiments of the present invention, and can be used alone or in combination, or other alternative solutions can also be selected.

[0051] To make the purpose, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below through experimental examples.

[0052] 1. Experimental materials

[0053] The raw materials and preparations involved in the present invention are all standard products that can be purchased on the market and can be directly used without purification.

[0054] 2. Preparation of bismuth oxybromide / alumina composite functional ceramic material

[0055] 2.1 Example 1

[0056] Dissolve 0.35 g of polyvinyl alcohol in 30 ml of water, then add 3.14 g of starch and 1.5 ml of glycerol to obtain a mixed suspension A for standby. Take 16 ml of the mixed suspension A and pour it into a ball milling tank containing 35 g of alumina grinding balls and 17.5 g of alumina powder, and ball mill for 4 h to obtain a ceramic slurry B with the solid and liquid phases fully and uniformly mixed. Pour the uniformly mixed ceramic slurry B into a PVC mold, freeze and solidify it at -30°C, and then carry out vacuum drying at -30°C to obtain a ceramic green body. Sinter the ceramic green body at 1400°C for 2 h, and naturally cool it to obtain alumina porous ceramics. Disperse bismuth oxybromide into deionized water to obtain a bismuth oxybromide suspension C with a concentration of 30 mg / ml. Coat the bismuth oxybromide suspension C on the surface of the alumina porous ceramics, and dry it at 60°C to obtain a bismuth oxybromide / alumina ceramic green body. Under a N2 atmosphere, sinter the bismuth oxybromide / alumina ceramic green body at 505°C for 1 h to obtain a bismuth oxybromide / alumina composite functional ceramic material.

[0057] 2.2 Example 2

[0058] Dissolve 0.3 g of polyvinyl alcohol in 28 ml of water, then add 1.76 g of starch and 2.0 ml of glycerol to obtain a mixed suspension A for standby. Take 15 ml of the mixed suspension A and pour it into a ball milling tank containing 35 g of alumina grinding balls and 14.5 g of alumina powder, and ball mill for 4 h to obtain a ceramic slurry B with the solid and liquid phases fully and uniformly mixed. Pour the uniformly mixed ceramic slurry B into a PVC mold, freeze and solidify it at -30°C, and then carry out vacuum drying at -10°C to obtain a ceramic green body. Sinter the ceramic green body at 1200°C for 4 h, and naturally cool it to obtain alumina porous ceramics. Disperse bismuth oxybromide into deionized water to obtain a bismuth oxybromide suspension C with a concentration of 40 mg / ml. Coat the bismuth oxybromide suspension C on the surface of the alumina porous ceramics, and dry it at 50°C to obtain a bismuth oxybromide / alumina ceramic green body. Under a N2 atmosphere, sinter the bismuth oxybromide / alumina ceramic green body at 510°C for 1 h to obtain a bismuth oxybromide / alumina composite functional ceramic material.

[0059] 2.3 Example 3

[0060] Dissolve 0.5 g of polyvinyl alcohol in 30 ml of water, then add 5.26 g of starch and 2.5 ml of glycerol to obtain a mixed suspension A for standby. Take 16.5 ml of the mixed suspension A and pour it into a ball milling tank containing 35 g of alumina grinding balls and 24.5 g of alumina powder, and ball mill for 4 h to obtain a ceramic slurry B with fully mixed solid and liquid phases. Pour the well-mixed ceramic slurry B into a PVC mold, freeze and solidify it at -40°C, and then conduct vacuum drying at 0°C to obtain a ceramic green body. Sinter the ceramic green body at 1300°C for 3 h, and naturally cool it to obtain alumina porous ceramics. Disperse bismuth oxybromide in deionized water to obtain a bismuth oxybromide suspension C with a concentration of 20 mg / ml. Coat the bismuth oxybromide suspension C on the surface of the alumina porous ceramics, and after drying at 60°C, obtain a bismuth oxybromide / alumina ceramic green body. Under a N2 atmosphere, sinter the bismuth oxybromide / alumina ceramic green body at 505°C for 1 h to obtain a bismuth oxybromide / alumina composite functional ceramic material.

[0061] 2.4 Example 4

[0062] Dissolve 0.36 g of polyvinyl alcohol in 34 ml of water, then add 5.5 g of starch and 3.1 ml of glycerol to obtain a mixed suspension A for standby. Take 19 ml of the mixed suspension A and pour it into a ball milling tank containing 35 g of alumina grinding balls and 17.5 g of alumina powder, and ball mill for 4 h to obtain a ceramic slurry B with fully mixed solid and liquid phases. Pour the well-mixed ceramic slurry B into a PVC mold, freeze and solidify it at -40°C, and then conduct vacuum drying at -5°C to obtain a ceramic green body. Sinter the ceramic green body at 1400°C for 2 h, and naturally cool it to obtain alumina porous ceramics. Disperse bismuth oxybromide in deionized water to obtain a bismuth oxybromide suspension C with a concentration of 10 mg / ml. Coat the bismuth oxybromide suspension C on the surface of the alumina porous ceramics, and after drying at 60°C, obtain a bismuth oxybromide / alumina ceramic green body. Under a N2 atmosphere, sinter the bismuth oxybromide / alumina ceramic green body at 460°C for 1 h to obtain a bismuth oxybromide / alumina composite functional ceramic material.

[0063] 2.5 Example 5

[0064] Dissolve 0.32 g of polyvinyl alcohol in 26 ml of water, then add 1.5 g of starch and 1.5 ml of glycerol to obtain a mixed suspension A for standby. Take 14 ml of the mixed suspension A and pour it into a ball milling tank containing 35 g of alumina grinding balls and 15.5 g of alumina powder, and ball mill for 4 h to obtain a ceramic slurry B with the solid and liquid phases fully and uniformly mixed. Pour the uniformly mixed ceramic slurry B into a PVC mold, freeze and solidify it at -40 °C, and then carry out vacuum drying at -10 °C to obtain a ceramic green body. Sinter the ceramic green body at 1350 °C for 2.5 h, and naturally cool it to obtain alumina porous ceramics. Disperse bismuth oxybromide into deionized water to obtain a bismuth oxybromide suspension C with a concentration of 30 mg / ml. Coat the bismuth oxybromide suspension C on the surface of the alumina porous ceramics, and after drying at 50 °C, obtain a bismuth oxybromide / alumina ceramic green body. Under a N2 atmosphere, sinter the bismuth oxybromide / alumina ceramic green body at 530 °C for 1 h to obtain a bismuth oxybromide / alumina composite functional ceramic material.

[0065] 2.6 Example 6

[0066] Dissolve 0.42 g of polyvinyl alcohol in 30 ml of water, then add 3.5 g of starch and 1.5 ml of glycerol to obtain a mixed suspension A for standby. Take 16 ml of the mixed suspension A and pour it into a ball milling tank containing 35 g of alumina grinding balls and 20.5 g of alumina powder, and ball mill for 4 h to obtain a ceramic slurry B with the solid and liquid phases fully and uniformly mixed. Pour the uniformly mixed ceramic slurry B into a PVC mold, freeze and solidify it at -30 °C, and then carry out vacuum drying at 3 °C to obtain a ceramic green body. Sinter the ceramic green body at 1400 °C for 2 h, and naturally cool it to obtain alumina porous ceramics. Disperse bismuth oxybromide into deionized water to obtain a bismuth oxybromide suspension C with a concentration of 20 mg / ml. Coat the bismuth oxybromide suspension C on the surface of the alumina porous ceramics, and after drying at 70 °C, obtain a bismuth oxybromide / alumina ceramic green body. Under a N2 atmosphere, sinter the bismuth oxybromide / alumina ceramic green body at 555 °C for 1 h to obtain a bismuth oxybromide / alumina composite functional ceramic material.

[0067] 3. Analysis of the photocatalytic degradation efficiency of bismuth oxybromide / alumina composite functional ceramic materials on rhodamine B

[0068] The degradation performance tests were carried out on the above six composite functional ceramic material samples, and Rhodamine B was selected as the object of photocatalytic degradation. It should be noted that for the convenience of experimental comparison, the above composite functional ceramic materials were all prepared into samples with a thickness of 5 mm and a diameter of 15 mm, placed in a transparent pipe with an inner diameter of 15 mm, and a Rhodamine B solution with a concentration of 10 mg / ml was injected into the pipe, allowing it to flow through the composite functional ceramic material at a flow rate of 0.01 mm / s. The photocatalytic degradation performance tests were respectively carried out on the samples in the six groups of examples. The light source was a 300 W xenon lamp with a wavelength λ≥420 nm. The results of the photocatalytic degradation efficiency of Rhodamine B are as Figure 2 shown; the XRD patterns of the six material samples are as Figure 3 shown.

[0069] From Figure 2 it can be seen that Rhodamine B has a large peak in the wavelength range of 500 - 600 nm, which indicates that Rhodamine B can absorb a large amount of light with wavelengths of 500 - 600 nm. Especially at a wavelength of about 550 nm, it is the maximum absorption wavelength of Rhodamine B. It can be seen from the figure that under the continuous flow state, the direct degradation rate of the bismuth oxybromide / aluminum oxide composite functional ceramics prepared in the six examples for Rhodamine B is above 71%, with an average of 82%. Especially for the sample of Example 2, the direct degradation rate of Rhodamine B is as high as 96%, and the degradation effect is excellent.

[0070] The above embodiments only represent several implementation manners of the present application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the appended claims.

Claims

1. A preparation method of a bismuth oxybromide / aluminum oxide composite functional ceramic material, characterized in that, It includes the following steps: S10. Add a binder, an open-pore forming agent, and a plasticizing auxiliary agent into deionized water, and mix evenly to obtain a mixed suspension A; S20. Mix and ball-mill the mixed suspension A with grinding balls and alumina powder to obtain a ceramic slurry B; S30. After the ceramic slurry B is frozen and solidified, vacuum-dry it to obtain a ceramic green body, and then sinter the ceramic green body and cool it naturally to obtain porous alumina ceramics; S40. Disperse bismuth oxybromide into deionized water to obtain a bismuth oxybromide suspension C with a concentration of 10 to 40 mg / l for standby; S50. Uniformly coat the bismuth oxybromide suspension C on the surface of the porous alumina ceramics, and after drying, obtain a bismuth oxybromide / alumina composite ceramic green body; S60. Under an inert atmosphere, secondarily sinter the bismuth oxybromide / alumina ceramic green body to obtain the bismuth oxybromide / alumina composite functional ceramic material.

2. The preparation method of the bismuth oxybromide / aluminum oxide composite functional ceramic material according to claim 1, wherein, In step S10, the addition ratio of the binder, the open-pore forming agent, the plasticizing auxiliary agent to deionized water is (0.10 g to 0.25 g):(0.8 g to 3.0 g):(0.75 ml to 1.7 ml):(13 ml to 17 ml).

3. The preparation method of the bismuth oxybromide / aluminum oxide composite functional ceramic material according to claim 1, wherein, In step S10, the binder includes at least one of polyvinyl alcohol, sodium carboxymethyl cellulose, and polyacrylamide.

4. The preparation method of the bismuth oxybromide / aluminum oxide composite functional ceramic material according to claim 1, wherein In step S10, the open-pore forming agent includes at least one of starch, sawdust, rice husk, and carbon powder.

5. The preparation method of the bismuth oxybromide / aluminum oxide composite functional ceramic material according to claim 1, characterized in that, In step S10, the plasticizing auxiliary agent includes at least one of glycerol, polyethylene glycol, and hydroxyethyl methyl cellulose.

6. The preparation method of the bismuth oxybromide / aluminum oxide composite functional ceramic material according to claim 1, characterized in that, In step S20, the addition ratio of the mixed suspension A, the grinding balls, and the alumina powder is (14 ml to 20 ml):(25 g to 45 g):(14.5 g to 24.5 g).

7. The preparation method of the bismuth oxybromide / aluminum oxide composite functional ceramic material according to claim 1, characterized in that, In step S30, the sintering temperature is 1100 to 1600 °C, and the sintering time ≥ 1 h.

8. The preparation method of the bismuth oxybromide / aluminum oxide composite functional ceramic material according to claim 1, characterized in that In step S30, the freezing and solidifying temperature is below -10 °C, and the vacuum drying temperature is -30 to 5 °C.

9. The preparation method of the bismuth oxybromide / aluminum oxide composite functional ceramic material according to claim 1, characterized in that, In step S60, the secondary sintering temperature is 400 to 580 °C, and the secondary sintering time is 1 ± 0.5 h.

10. A bismuth oxybromide / aluminum oxide composite functional ceramic material, characterized in that, It is prepared by using the preparation method of the bismuth oxybromide / alumina composite functional ceramic material according to any one of claims 1 to 9.

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