A method for electron beam irradiation-induced synthesis of titanium dioxide

Abstract

The application provides a method for synthesizing titanium dioxide by electron beam irradiation and belongs to the technical field of titanium dioxide material preparation. In a closed container, tetrabutyl titanate without dilution by an external solvent is subjected to electron beam irradiation, and the obtained irradiation product is sequentially subjected to centrifugation, drying and grinding to obtain an amorphous organic titanium precursor; the obtained amorphous organic titanium precursor is subjected to heat treatment to obtain anatase titanium dioxide. The preparation method does not need an external hydrolysis agent, a precipitating agent, a reducing agent or a surfactant, utilizes high-energy electron beam irradiation to induce tetrabutyl titanate to combine, and then utilizes subsequent heat treatment to prepare anatase titanium dioxide with an anatase crystal phase, so that the overall process flow is simple, the conditions are mild, the irradiation dose is controllable, a complex sol-gel formula or a strong reducing agent is not needed, a new process route is provided for electron beam assisted preparation of titanium dioxide, and the like.

Description

Technical Field

[0001] This invention relates to the field of titanium dioxide material preparation technology, and in particular to a method for electron beam irradiation-induced synthesis of titanium dioxide. Background Technology

[0002] Titanium dioxide (TiO2) is an important wide-bandgap semiconductor material. It is chemically stable, non-toxic, and inexpensive, and has wide applications in photocatalysis, solar cells, energy storage electrodes, gas sensors, and anti-corrosion coatings. Titanium dioxide exists in three main crystal forms: anatase, rutile, and brookite. Among these, the anatase phase typically exhibits higher photocatalytic activity and has therefore attracted widespread attention.

[0003] Currently, anatase titanium dioxide is commonly prepared via sol-gel, hydrothermal, precipitation, aldolothermic, or high-temperature calcination methods. Some existing methods suffer from problems such as complex system composition, long reaction times, and the need for high-pressure equipment or subsequent high-temperature treatment. Tetrabutyl titanate is one of the most commonly used organotitanium precursors for titanium dioxide preparation; however, the traditional tetrabutyl titanate sol-gel route typically requires the addition of water, alcohol, acid, alkali, complexing agents, or surfactants to control the hydrolysis rate and particle morphology, resulting in a complex system composition, a narrow process window, and the need for subsequent heat treatment at a certain temperature to obtain crystalline titanium dioxide. Given the current state of research on titanium dioxide preparation, further research is necessary. Summary of the Invention

[0004] The purpose of this invention is to provide a method for electron beam irradiation-induced synthesis of titanium dioxide, which solves the problems of harsh conditions and difficulty in controlling defect concentration in existing titanium dioxide preparation methods.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a method for electron beam irradiation-induced synthesis of titanium dioxide, comprising the following steps: Tetrabutyl titanate was irradiated with an electron beam in a sealed container to obtain the irradiated product. The irradiated product was centrifuged, dried, and ground sequentially to obtain an amorphous organic titanium precursor. The amorphous organic titanium precursor was heat-treated to obtain anatase titanium dioxide. The tetrabutyl titanate is tetrabutyl titanate that has not been diluted with an external solvent.

[0006] Preferably, the energy of the electron beam is 1-2 MeV.

[0007] Preferably, the total absorbed dose of the irradiation is 50-1000 kGy, the irradiation temperature is 25-30℃, and the irradiation dose rate is 1.43-28.6 kGy / min.

[0008] Preferably, the thickness of the liquid layer of tetrabutyl titanate in the direction of electron beam incidence is 0.5-2 mm.

[0009] Preferably, the centrifugation speed is 6000-10000 rpm and the time is 10-20 min.

[0010] Preferably, the drying is carried out under a protective atmosphere, at a temperature of 40-80°C, for a time of 8-24 hours.

[0011] Preferably, the grinding time is 5-10 min.

[0012] Preferably, the heating rate of the heat treatment is 1-20℃ / min, the temperature of the heat treatment is 300-800℃, and the time is 0.5-5 h.

[0013] The beneficial effects of this invention are: This invention uses undiluted tetrabutyl titanate as both a solvent and a titanium source. The tetrabutyl titanate is irradiated with an electron beam to obtain an irradiated product. This irradiated product is then subjected to centrifugation, drying, and heat treatment to obtain anatase titanium dioxide. This method eliminates the need for external hydrolysants, precipitants, reducing agents, or surfactants. It utilizes high-energy electron beam irradiation to induce the combination of tetrabutyl titanate and subsequent heat treatment to prepare anatase-phase titanium dioxide. The overall process is simple, with mild conditions and controllable irradiation dosage. It does not require complex sol-gel formulations or strong reducing agents, providing a novel process route for electron beam-assisted titanium dioxide preparation. Attached Figure Description

[0014] Figure 1 The XRD patterns are of the titanium dioxide prepared in Examples 1-3; Figure 2 Thermogravimetric-differential scanning calorimetry (TGC) curve of the amorphous organic titanium precursor in Example 1; Figure 3 Thermogravimetric-differential scanning calorimetry (TGC) curve of the amorphous organic titanium precursor in Example 2; Figure 4 The thermogravimetric-differential scanning calorimetry curve of the amorphous organic titanium precursor in Example 3 is shown. Detailed Implementation

[0015] This invention provides a method for electron beam irradiation-induced synthesis of titanium dioxide, characterized by comprising the following steps: Tetrabutyl titanate was irradiated with an electron beam in a sealed container to obtain the irradiated product. The irradiated product was centrifuged, dried, and ground sequentially to obtain an amorphous organic titanium precursor. The amorphous organic titanium precursor was heat-treated to obtain anatase titanium dioxide. The tetrabutyl titanate is tetrabutyl titanate that has not been diluted with an external solvent.

[0016] In this invention, unless otherwise specified, all raw materials required for preparation are commercially available products well known to those skilled in the art.

[0017] In this invention, tetrabutyl titanate is preferably placed in a sealed container and the air is vented. After being irradiated with an electron beam, the color of tetrabutyl titanate changes, and the irradiated product is obtained.

[0018] In this invention, the tetrabutyl titanate is undiluted pure tetrabutyl titanate, and no water, alcohol solvents, acids or surfactants are added before irradiation. The system composition is simple and the process route is concise. The mass fraction of the tetrabutyl titanate is preferably 96.0-100%, and more preferably greater than 99.0%.

[0019] In this invention, the energy of the electron beam is preferably 1-2 MeV, more preferably 1.8 MeV; the total absorbed dose of the irradiation is preferably 50-1000 kGy, more preferably 200 kGy, and the total absorbed dose is accumulated in a continuous irradiation manner to reach the total absorbed dose, with the sample moving at a uniform speed in the irradiation field to complete the entire irradiation process; the irradiation temperature is preferably 25-30℃, more preferably 25℃; the irradiation dose rate is preferably 1.43-28.6 kGy / min, more preferably 14.3 kGy / min.

[0020] In this invention, the thickness of the tetrabutyl titanate liquid layer in the electron beam incident direction is preferably 0.5-2 mm, and more preferably 1 mm.

[0021] The present invention preferably involves solid-liquid separation of the above-mentioned irradiation product, followed by drying and grinding of the resulting precipitate to obtain an amorphous organic titanium precursor.

[0022] In this invention, the solid-liquid separation method is preferably centrifugation, the centrifugation speed is preferably 6000-10000 rpm, more preferably 8000 rpm, and the time is preferably 10-20 min, more preferably 12 min.

[0023] In this invention, the drying is preferably carried out under a protective atmosphere, which preferably includes a vacuum atmosphere or an inert gas atmosphere, and more preferably under an argon atmosphere; the drying temperature is preferably 40-80℃, more preferably 60℃, and the drying time is preferably 8-24 h, more preferably 18 h; the low-temperature drying product of this invention can maintain an amorphous state, and can be converted into anatase titanium dioxide by subsequent heat treatment at a lower temperature, thereby reducing the crystallization temperature and process complexity.

[0024] In this invention, the grinding time is preferably 5-10 min, and more preferably 8 min.

[0025] The present invention preferably involves heat-treating the above-mentioned amorphous organic titanium precursor. During the heat treatment process, the amorphous organic titanium precursor undergoes severe weight loss, accompanied by a sharp exothermic peak, and the corresponding butyl organic group undergoes rapid thermal decomposition to obtain anatase titanium dioxide.

[0026] In this invention, the heating rate of the heat treatment is preferably 1-20℃ / min, more preferably 10℃ / min; the temperature of the heat treatment is preferably 300-800℃, more preferably 400-800℃, and the time is preferably 0.5-5 h, more preferably 1.5 h.

[0027] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0028] The tetrabutyl titanate used in Examples 1-3 was undiluted pure tetrabutyl titanate, with no water, alcohol solvents, acids or surfactants added before irradiation, and a mass fraction greater than 99.0%.

[0029] Example 1

[0030] 10 mL of tetrabutyl titanate was placed in an aluminum bag, sealed, and the air was removed. It was then irradiated by continuous irradiation with an electron beam of 1.8 MeV. The liquid layer thickness of tetrabutyl titanate in the direction of electron beam incident was 1 mm. The total absorbed dose was 200 kGy, the irradiation temperature was 25℃, and the irradiation dose rate was 14.3 kGy / min. The irradiated product was obtained. The irradiated product was centrifuged at 8000 rpm for 10 min, and the green precipitate was collected. The green precipitate was dried in a tube furnace at 60°C for 18 h and then manually ground in a mortar for 8 min to obtain an amorphous organic titanium precursor. Amorphous organic titanium precursor was heat-treated to 400℃ for 40 min at a rate of 10℃ / min under argon atmosphere to obtain titanium dioxide.

[0031] Example 2

[0032] The only difference from Example 1 is: The amorphous organic titanium precursor was heat-treated at 800℃ for 1.5h under an argon atmosphere at a rate of 10℃ / min. With all other parameters unchanged, titanium dioxide was obtained.

[0033] Example 3

[0034] The only difference from Example 1 is: The total absorbed dose from irradiation is 500 kGy; The amorphous organic titanium precursor was heat-treated at 800℃ for 1.5h under an argon atmosphere at a rate of 10℃ / min. With all other parameters unchanged, titanium dioxide was obtained.

[0035] Characterization and performance testing

[0036] 1. Figure 1 The images show the XRD patterns of titanium dioxide prepared in Examples 1-3, indicating that anatase titanium dioxide was prepared in all three examples.

[0037] 2. Figures 2-4 The thermogravimetric-differential scanning calorimetry curves of the amorphous organic titanium precursors in Examples 1-3 are shown respectively. It can be seen that tetrabutyl titanate can be converted into anatase titanium dioxide by heat treatment at a relatively low temperature after high-energy electron beam irradiation.

[0038] As can be seen from the above, this invention provides a method for electron beam irradiation-induced synthesis of titanium dioxide, which directly uses tetrabutyl titanate itself, without the addition of external solvent dilution, as both solvent and titanium source. No additional hydrolysate, surfactant, or other additives are required, resulting in a simple system composition that avoids the pollution and costs introduced by complex formulations and unnecessary reagents. This invention uses high-energy electron beam irradiation to induce the synthesis of anatase titanium dioxide by combining tetrabutyl titanate with subsequent heat treatment. The overall process is simple, the conditions are mild, and the irradiation dose is controllable, providing a novel, green, and efficient route for the preparation of anatase titanium dioxide.

[0039] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for electron beam irradiation-induced synthesis of titanium dioxide, characterized in that, Includes the following steps: Tetrabutyl titanate was irradiated with an electron beam in a sealed container to obtain the irradiated product. The irradiated product was centrifuged, dried, and ground sequentially to obtain an amorphous organic titanium precursor. The amorphous organic titanium precursor was heat-treated to obtain anatase titanium dioxide. The tetrabutyl titanate is tetrabutyl titanate that has not been diluted with an external solvent.

2. The method according to claim 1, characterized in that, The energy of the electron beam is 1-2 MeV.

3. The method according to claim 2, characterized in that, The total absorbed dose of the irradiation is 50-1000 kGy, the irradiation temperature is 25-30℃, and the irradiation dose rate is 1.43-28.6 kGy / min.

4. The method according to claim 1, characterized in that, The thickness of the tetrabutyl titanate liquid layer in the direction of electron beam incidence is 0.5-2 mm.

5. The method according to claim 1, characterized in that, The centrifugation speed is 6000-10000 rpm, and the time is 10-20 min.

6. The method according to claim 5, characterized in that, The drying is carried out under a protective atmosphere at a temperature of 40-80°C for 8-24 hours.

7. The method according to claim 6, characterized in that, The grinding time is 5-10 minutes.

8. The method according to claim 1 or 7, characterized in that, The heating rate of the heat treatment is 1-20℃ / min, the temperature of the heat treatment is 300-800℃, and the time is 0.5-5 h.

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