Preparation method of nano titanium dioxide with controllable crystal face

Abstract

The invention relates to the technical field of semiconductor photocatalytic materials, in particular to a preparation method of crystal face controllable nano titanium dioxide, which comprises the following steps: establishing an anatase type TiO2 model; one or more external atom sources selected from a C atom source, an N atom source, a Fe atom source, a Co atom source, a Ni atom source, a Cu atom source, a Zn atom source, a Mo atom source, a Sn atom source and a W atom source are introduced into crystal lattices of the TiO2 model according to the doping proportions of the different external atom sources, the specific positions of the different external atom sources in the crystal lattices and the like. Foreign atoms are introduced into TiO2 crystal lattices and surfaces, the crystal lattice structure, electron cloud distribution, the surface dangling bond state and vacancy defects of the TiO2 crystal lattices are changed, the surface energy of the {101} crystal face and the {001} crystal face is regulated and controlled fundamentally, and accurate regulation and control of the exposure proportion of the crystal faces can be achieved without depending on a traditional fluorine ion additive.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor photocatalytic materials, and more particularly to a preparation method of nanometer titanium dioxide with controllable crystal faces. BACKGROUND

[0002] Anatase titanium dioxide (TiO2) can absorb ultraviolet light to generate free radicals with high chemical activity, and has the characteristics of low cost, safety and stability, and has broad application prospects in pollution control, hydrogen production, CO2 reduction and organic synthesis; TiO2 is tetragonal, and common crystal faces are {101} and {001}, wherein the surface energy of the {001} crystal face is 0.90 J / m 2 , and the surface energy of the {101} crystal face is 0.44 J / m 2 . According to the Wuff rule, the ground state geometry of a cluster requires that the surface energy or surface area is minimized, so the growth rate of TiO2 along the

[001] direction is faster than that along the

[101] direction, resulting in that the exposed face of TiO2 is mainly the low-energy {101} crystal face, and under normal circumstances, the exposure ratio of the {001} crystal face is not more than 10%. However, it has been found that the active site ratio of the {001} crystal face is higher, and increasing the exposure ratio of the {001} crystal face can improve the photocatalytic activity of TiO2. Meanwhile, the {001} crystal face can form a {001} / {101} crystal face heterojunction to promote the separation of photo-generated electrons and holes, and further improve the photocatalytic efficiency, so it is an important research direction to prepare TiO2 with a high exposure ratio of the {001} crystal face. However, the existing technology commonly uses fluorine ion treatment to prepare TiO2 with a high exposure ratio of the {001} crystal face. Because fluorine ions can be adsorbed on the surface of the {001} crystal face, the surface energy of the {001} crystal face is reduced, and the growth rate of TiO2 along the

[001] direction is slowed down, so that the {001} crystal face can be exposed up to 90%. However, this method has the following disadvantages: 1. Fluorine ions are corrosive and toxic, and can pollute and damage the environment; 2. The surface energy of the {001} crystal face after adsorbing fluorine ions is a fixed value, so the growth rate along the

[001] direction is also a fixed value, and it is difficult to control the exposure ratio of the {001} / {101} crystal face, and the optimal crystal face heterojunction cannot be achieved; 3. The prepared TiO2 is an ultraviolet-responsive TiO2, which has no absorption of visible light and low light energy utilization rate. SUMMARY

[0003] The present application provides a preparation method of nanometer titanium dioxide with controllable crystal faces.

[0004] To achieve the above objectives, the present invention specifically adopts the following technical solution: This invention proposes a method for preparing nano-titanium dioxide with controllable crystal planes. Without using fluorine additives, it introduces external atoms to regulate the lattice structure and surface energy, achieving controllable exposure ratios of {101} and {001} crystal planes and enabling visible light photocatalysis. The method specifically includes the following steps: (1) Establish an anatase TiO2 model containing 108 titanium atoms and 216 oxygen atoms. Introduce one or more foreign atomic sources selected from C, N, Fe, Co, Ni, Cu, Zn, Mo, Sn and W into the TiO2 model lattice. Calculate the surface energy of the {001} and {101} crystal planes and the exposure ratio of the {101} crystal plane to the {001} crystal plane in the lattice, based on the doping ratio of different foreign atomic sources and their specific positions in the lattice. This will determine the theoretical doping parameters required to achieve the exposure ratio of the {101} crystal plane to the {001} crystal plane. The proportion of foreign atomic sources corresponding to the expected {101} crystal plane / {001} crystal plane exposure ratio and their positions in the TiO2 lattice can be obtained by calculation, without having to conduct a large number of experiments to obtain the desired {101} crystal plane / {001} crystal plane exposure ratio. (2) Add the titanium source, precipitant and foreign atom source to deionized water according to the theoretical doping parameters determined in step (1), stir evenly to generate a white hydrated precipitate, wash the precipitate and add a solvent to form a transparent liquid with "titanium-foreign atom" complex molecules; (3) Add crystal growth regulator to transparent liquid, stir evenly and carry out hydrothermal reaction (under hydrothermal conditions, complex molecules crystallize to generate an aqueous solution of nano TiO2 crystals. The role of crystal growth regulator is to control the crystallization process so that the number and position of foreign atoms in TiO2 crystals are the same as the calculation results) to obtain nano titanium dioxide with controllable exposure ratio of {101} crystal face / {001} crystal face and visible light catalytic ability. The molar ratio of each foreign atomic source to titanium atoms is 0.1% to 20%. The amount of precipitant used is 100% to 400% of the molar amount of the titanium source; The amount of solvent used is 50% to 200% of the molar amount of the titanium source; The amount of crystal growth regulator used is 0.1% to 20% of the molar amount of titanium source.

[0005] As a preferred technical solution of the present invention, the specific types of external atomic sources and their corresponding raw materials in step (1) are as follows: The C atom source is one or more of glucose and fructose; The N atom source is one or more of guanidine hydrochloride and guanidine nitrate; The Fe atom source is one or more of ferrous sulfate, ferric sulfate, ferric chloride, ferrous nitrate, and ferric nitrate. The Co atom source is one or more of cobalt sulfate, cobalt chloride, and cobalt nitrate; The Ni atom source is one or more of nickel sulfate and nickel nitrate; The Cu atom source is one or more of copper sulfate, copper nitrate, and copper chloride; The Zn atom source is one or more of zinc sulfate and zinc chloride; The Mo atom source is one or more of sodium molybdate, ammonium molybdate, and potassium molybdate. The Sn atom source is stannous chloride; The W atom source is one or more of sodium tungstate, ammonium tungstate, and potassium tungstate.

[0006] As a preferred technical solution of the present invention, the titanium source in step (2) is one or more of titanium oxysulfate, titanium sulfate, titanium tetrachloride, and titanium trichloride.

[0007] As a preferred technical solution of the present invention, the precipitant in step (2) is one or more of ammonia, sodium hydroxide, sodium carbonate, and sodium bicarbonate.

[0008] As a preferred technical solution of the present invention, the solvent in step (2) is one or more of hydrogen peroxide, sodium peroxide, and potassium peroxide.

[0009] As a preferred technical solution of the present invention, the crystal growth regulator in step (3) is one or more of hydrazine hydrate, sodium borohydride, sodium peroxide, and peracetic acid, and its addition amount is 0.1% to 20% of the molar amount of titanium atoms.

[0010] As a preferred technical solution of the present invention, the temperature of the hydrothermal reaction in step (3) is 80℃~200℃ and the hydrothermal time is 4h~72h.

[0011] As a preferred technical solution of the present invention, the calculation in step (1) adopts density functional theory and combines Wulff rule to predict the exposure ratio of {101} crystal plane / {001} crystal plane, thereby determining the theoretical doping parameters required to achieve the exposure ratio of {101} crystal plane / {001} crystal plane. Density functional theory specifically involves the following steps: Model construction: The anatase TiO2 model (Ti4O8) was called from the Materials Studio's built-in model library to build a 3×3×3 supercell (Ti108 O 216 ); Calculation parameter settings: The electron exchange correlation is described by the PBE functional (Perdew-Burke-Ernzerhof) under the generalized gradient approximation (GGA). The plane wave cutoff energy is set to 400–500 eV. The convergence criterion for the self-consistent field of the K-point network in the calculation is set to energy less than 2 × 10⁻⁶ eV. -5 The system has a maximum stress of less than 0.1 GPa and a maximum displacement of less than 0.002 Å. The self-consistent field cyclic convergence criterion for system energy is set to 1×10⁻⁵ eV, and the ion stress optimization convergence criterion is set to 0.01 eV·Å. -1 ; Surface energy calculation: Slab models (5-7 atomic layers thick) of the {001} and {101} crystal planes were constructed respectively. A vacuum layer with a thickness of 15 Å was added in the Z-axis direction to eliminate periodic boundary interference. The surface energy y is calculated as: y = E slab -n×E bulk / 2A; E slab E represents the total energy (eV) of the slab model, where n is the sum of the number of Ti and O atoms in the slab model. bulk denoted as the average energy of a single TiO2 atom (eV / atom), and A is the surface area of ​​the crystal plane (A). Crystal plane exposure ratio: Based on Wulff's rule, the equilibrium morphology of a crystal is determined by minimizing the product of the surface energy and area of ​​each crystal plane; for the {101} and {001} crystal planes of anatase TiO2, their exposed area ratio satisfies: (1-0.3693k) 2 / [(1-0.3693k) 2 +k(2-0.3693k)]; k is the surface energy ratio of the {001} crystal plane and the {101} crystal plane; The beneficial effects of this invention are as follows: This invention introduces foreign atoms into the TiO2 lattice and surface, altering its lattice structure, electron cloud distribution, surface dangling bond state, and vacancy defects. This fundamentally controls the surface energy of the {101} and {001} crystal planes, achieving precise control of the crystal plane exposure ratio without relying on traditional fluoride ion additives. Specifically, since the surface energy of the {101} and {001} crystal planes is adjustable, the growth rate of the crystal orientation is controllable, allowing for flexible adjustment of the composition ratio of the {101} / {001} crystal plane heterojunction on the synthesized TiO2 crystal surface. Furthermore, the introduction of foreign atoms and the vacancy defects generated during charge balancing effectively expand the light absorption range of TiO2, enabling it to possess visible light response capabilities and significantly improving light energy utilization. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of a TEM image of the original, unmodified TiO2 in Example 1; Figure 2 This is a schematic diagram of an HRTEM image of TiO2 when Mo:Ti = 10% in Example 1; Figure 3 This is a schematic diagram of a TEM image of the original unmodified TiO2 in Example 2; Figure 4 This is a schematic diagram of the HRTEM image of TiO2 when W:Ti=5% in Example 2; Figure 5 This is a graph showing the visible light catalytic purification performance of TiO2 after introducing 10% Mo atoms in Example 1; Figure 6 This is a graph showing the visible light catalytic purification performance of TiO2 after introducing 5% W atoms in Example 2. Detailed Implementation

[0013] This invention proposes a method for preparing nano-titanium dioxide with controllable crystal planes. Without using fluorine additives, it introduces external atoms to regulate the lattice structure and surface energy, achieving controllable exposure ratios of {101} and {001} crystal planes and enabling visible light photocatalysis. The method specifically includes the following steps: (1) Establish an anatase TiO2 model containing 108 titanium atoms and 216 oxygen atoms. Introduce one or more foreign atomic sources selected from C, N, Fe, Co, Ni, Cu, Zn, Mo, Sn and W into the TiO2 model lattice. Calculate the surface energy of the {001} and {101} crystal planes and the exposure ratio of the {101} crystal plane to the {001} crystal plane in the lattice, based on the doping ratio of different foreign atomic sources and their specific positions in the lattice. This will determine the theoretical doping parameters required to achieve the exposure ratio of the {101} crystal plane to the {001} crystal plane. The proportion of foreign atomic sources corresponding to the expected {101} crystal plane / {001} crystal plane exposure ratio and their positions in the TiO2 lattice can be obtained by calculation, without having to conduct a large number of experiments to obtain the desired {101} crystal plane / {001} crystal plane exposure ratio. (2) Add the titanium source, precipitant and foreign atom source to deionized water according to the theoretical doping parameters determined in step (1), stir evenly to generate a white hydrated precipitate, wash the precipitate and add a solvent to form a transparent liquid with "titanium-foreign atom" complex molecules; (3) Add a crystal growth regulator to a transparent liquid, stir evenly, and then carry out a hydrothermal reaction (under hydrothermal conditions, complex molecules crystallize to generate an aqueous solution of nano-TiO2 crystals. The role of the crystal growth regulator is to control the crystallization process so that the number and position of foreign atoms in the TiO2 crystal are the same as the calculation results), and obtain nano-titanium dioxide with controllable exposure ratio of {101} crystal face / {001} crystal face and visible light catalytic ability; in the process of regulating crystallization, regulate the process of metal ions entering the TiO2 lattice to ensure that the actual sites are consistent with the calculation results; The final result is a TiO2 crystal with controllable {101} and {001} exposure ratio obtained without the use of fluorine additives, while also possessing visible light photocatalytic ability. The molar ratio of each foreign atomic source to titanium atoms is 0.1% to 20%. The amount of precipitant used is 100% to 400% of the molar amount of the titanium source; The amount of solvent used is 50% to 200% of the molar amount of the titanium source; The amount of crystal growth regulator used is 0.1% to 20% of the molar amount of titanium source.

[0014] As a preferred technical solution of the present invention, the specific types of external atomic sources and their corresponding raw materials in step (1) are as follows: The C atom source is one or more of glucose and fructose; The N atom source is one or more of guanidine hydrochloride and guanidine nitrate; The Fe atom source is one or more of ferrous sulfate, ferric sulfate, ferric chloride, ferrous nitrate, and ferric nitrate. The Co atom source is one or more of cobalt sulfate, cobalt chloride, and cobalt nitrate; The Ni atom source is one or more of nickel sulfate and nickel nitrate; The Cu atom source is one or more of copper sulfate, copper nitrate, and copper chloride; The Zn atom source is one or more of zinc sulfate and zinc chloride; The Mo atom source is one or more of sodium molybdate, ammonium molybdate, and potassium molybdate. The Sn atom source is stannous chloride; The W atom source is one or more of sodium tungstate, ammonium tungstate, and potassium tungstate.

[0015] In step (2), the titanium source is one or more of titanium oxysulfate, titanium sulfate, titanium tetrachloride, and titanium trichloride.

[0016] The precipitant mentioned in step (2) is one or more of ammonia, sodium hydroxide, sodium carbonate, and sodium bicarbonate.

[0017] The solvent mentioned in step (2) is one or more of hydrogen peroxide, sodium peroxide, and potassium peroxide.

[0018] In step (3), the crystal growth regulator is one or more of hydrazine hydrate, sodium borohydride, sodium peroxide, and peracetic acid, and its addition amount is 0.1% to 20% of the molar amount of titanium atoms.

[0019] In step (3), the temperature of the hydrothermal reaction is 80℃~200℃ and the hydrothermal time is 4h~72h.

[0020] In step (1), the calculation is performed using density functional theory and combined with Wulff's rule to predict the exposure ratio of the {101} crystal plane / {001} crystal plane, thereby determining the theoretical doping parameters required to achieve the exposure ratio of the {101} crystal plane / {001} crystal plane. Density functional theory specifically involves the following steps: Model construction: The anatase TiO2 model (Ti4O8) was called from the Materials Studio's built-in model library to build a 3×3×3 supercell (Ti 108 O 216 ); Calculation parameter settings: The electron exchange correlation is described by the PBE functional (Perdew-Burke-Ernzerhof) under the generalized gradient approximation (GGA). The plane wave cutoff energy is set to 400–500 eV. The convergence criterion for the self-consistent field of the K-point network in the calculation is set to energy less than 2 × 10⁻⁶ eV. -5 The system has a maximum stress of less than 0.1 GPa and a maximum displacement of less than 0.002 Å. The self-consistent field cyclic convergence criterion for system energy is set to 1×10⁻⁵ eV, and the ion stress optimization convergence criterion is set to 0.01 eV·Å. -1 ; Surface energy calculation: Slab models (5-7 atomic layers thick) of the {001} and {101} crystal planes were constructed respectively. A vacuum layer with a thickness of 15 Å was added in the Z-axis direction to eliminate periodic boundary interference. The surface energy y is calculated as: y = E slab -n×E bulk / 2A; E slab E represents the total energy (eV) of the slab model, where n is the sum of the number of Ti and O atoms in the slab model. bulk denoted as the average energy of a single TiO2 atom (eV / atom), and A is the surface area of ​​the crystal plane (A). Crystal plane exposure ratio: Based on Wulff's rule, the equilibrium morphology of a crystal is determined by minimizing the product of the surface energy and area of ​​each crystal plane; for the {101} and {001} crystal planes of anatase TiO2, their exposed area ratio satisfies: (1-0.3693k) 2 / [(1-0.3693k) 2 +k(2-0.3693k)]; k is the surface energy ratio of the {001} crystal plane and the {101} crystal plane; This invention introduces foreign atoms into the TiO2 lattice and surface, altering its lattice structure, electron cloud distribution, surface dangling bond state, and vacancy defects. This fundamentally controls the surface energy of the {101} and {001} crystal planes, achieving precise control of the crystal plane exposure ratio without relying on traditional fluoride ion additives. Specifically, since the surface energy of the {101} and {001} crystal planes is adjustable, the growth rate of the crystal orientation is controllable, allowing for flexible adjustment of the composition ratio of the {101} / {001} crystal plane heterojunction on the synthesized TiO2 crystal surface. Furthermore, the introduction of foreign atoms and the vacancy defects generated during charge balancing effectively expand the light absorption range of TiO2, enabling it to possess visible light response capabilities and significantly improving light energy utilization. Example 1

[0021] (1) An anatase TiO2 model containing 108 titanium atoms and 216 oxygen atoms was established. Mo atom sources were introduced into it, with the number of Mo atoms being 10% of the molar ratio of titanium atoms. The exposure rate of the {001} crystal plane was calculated to be 34%, and the exposure rate of the {101} crystal plane was 66%. (2) Add the titanium source, precipitant, and foreign atom source to deionized water in a certain proportion, stir evenly to obtain a white precipitate, wash the white precipitate clean, and then add a solvent to obtain a transparent liquid with "titanium-foreign atom" complex molecules; the titanium source is titanium oxysulfate and titanium sulfate, the precipitant is ammonia and sodium hydroxide, the Mo atom source is sodium molybdate, and the solvent is sodium peroxide; the amount of precipitant added is 200% of the molar amount of titanium source; the molar ratio of Mo atoms to titanium atoms is 10%; the proportion of solvent is 150% of the molar amount of titanium source; (3) Add a crystal growth regulator to a transparent liquid at a ratio of 5% of the molar ratio of the titanium source, stir until homogeneous, and then perform hydrothermal treatment at a temperature of 120°C for 12 hours. The crystal growth regulator is hydrazine hydrate, and the amount of crystal growth regulator is 2% of the molar weight of titanium atoms. After implementation of Example 1, refer to Figure 1 , Figure 2 As shown: Figure 1 TEM image of the original unmodified TiO2, Figure 2The HRTEM image of TiO2 with Mo:Ti=10% shows that the original TiO2 morphology is spindle-shaped, mainly exposing the {101} crystal plane. After the introduction of Mo atoms, the aspect ratio of the particles becomes smaller, and the exposure ratio of the {001} crystal plane at both ends increases. Figure 5 It can be seen from the visible light photocatalytic purification performance of TiO2 and Mo10-TiO2 for benzene and phenol. As shown in the figure, the visible light photocatalytic purification performance of TiO2 is significantly increased after introducing 10% Mo atoms. Example 2

[0022] (1) A TiO2 model containing 108 titanium atoms and 216 oxygen atoms was established. W atoms were introduced into it, with the number of W atoms being 5% of the molar ratio of titanium atoms. The exposure rate of the {001} crystal plane was calculated to be 23%, and the exposure rate of the {101} crystal plane was 77%. (2) Add the titanium source, precipitant, and foreign atom source to deionized water in a certain proportion, stir evenly to obtain a white precipitate, wash the white precipitate clean, and then add a solvent to obtain a transparent liquid with "titanium-foreign atom" complex molecules; the titanium source is titanium tetrachloride, the precipitant is sodium hydroxide, the W atom source is sodium tungstate and ammonium tungstate, and the solvent is hydrogen peroxide; the amount of precipitant added is 230% of the molar amount of titanium source; the molar ratio of W atom source to titanium atom is 3%; and the proportion of solvent is 120% of the molar amount of titanium source. (3) Add a crystal growth regulator to the transparent liquid at a ratio of 10% of the molar ratio of the titanium source, stir evenly, and then perform hydrothermal treatment at a temperature of 150°C for 20 hours. The crystal growth regulator is hydrazine hydrate, and the amount of crystal growth regulator is 5% of the molar weight of titanium atoms. After implementation of Example 2, refer to Figure 3 , 4 As shown: Figure 3 This is an HRTEM image of the original unmodified TiO2. Figure 4 The image shows an HRTEM image of TiO2 with W:Ti=5%. It can be seen that the original TiO2 morphology is spindle-shaped, mainly exposing the {101} crystal plane. After the introduction of W atoms, the aspect ratio of the particles becomes smaller, and the exposure ratio of the {001} crystal plane at both ends increases. Figure 6 As can be seen from the figure, the visible light photocatalytic purification performance of TiO2 and W5-TiO2 for benzene and phenol is significantly increased after introducing 5% W atoms.

[0023] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0024] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for preparing a nanometer titanium dioxide with controllable crystal plane, characterized in that, The method comprises the following steps: (1) establishing a model of anatase TiO2, introducing one or more foreign atom sources selected from a C atom source, an N atom source, an Fe atom source, a Co atom source, a Ni atom source, a Cu atom source, a Zn atom source, a Mo atom source, a Sn atom source and a W atom source into the crystal lattice of the TiO2 model, calculating the surface energy of the {001} crystal face and the {101} crystal face in the crystal lattice and the exposure ratio of the {101} crystal face / {001} crystal face in the crystal lattice according to the doping ratio of different foreign atom sources and the specific position of the foreign atom sources in the crystal lattice, and determining the theoretical doping parameters required to achieve the exposure ratio of the {101} crystal face / {001} crystal face; (2) adding a titanium source, a precipitating agent and the foreign atom source into deionized water according to the theoretical doping parameters determined in step (1), stirring uniformly to generate a white hydrated precipitate, washing the precipitate and then adding a dissolving agent to form a transparent liquid of "titanium-foreign atom" complex molecules; (3) adding a crystallization growth regulator to the transparent liquid, stirring uniformly and then performing a hydrothermal reaction to obtain nanometer titanium dioxide with a controllable exposure ratio of the {101} crystal face / {001} crystal face and visible light catalytic ability; wherein the molar ratio of each foreign atom source to titanium atom is 0.1% to 20%; the amount of the precipitating agent is 100% to 400% of the molar amount of the titanium source; the amount of the dissolving agent is 50% to 200% of the molar amount of the titanium source; the amount of the crystallization growth regulator is 0.1% to 20% of the molar amount of the titanium source.

2. The method according to claim 1, wherein the method is characterized by, The anatase TiO2 model in step (1) comprises 108 titanium atoms and 216 oxygen atoms.

3. The method according to claim 1, wherein the method is characterized by, The specific types of the foreign atom sources in step (1) and the corresponding raw materials are as follows: the C atom source is one or more of glucose and fructose; the N atom source is one or more of guanidine hydrochloride and guanidine nitrate; the Fe atom source is one or more of ferrous sulfate, iron sulfate, iron chloride, ferrous nitrate and iron nitrate; the Co atom source is one or more of cobalt sulfate, cobalt chloride and cobalt nitrate; the Ni atom source is one or more of nickel sulfate and nickel nitrate; the Cu atom source is one or more of copper sulfate, copper nitrate and copper chloride; the Zn atom source is one or more of zinc sulfate and zinc chloride; the Mo atom source is one or more of sodium molybdate, ammonium molybdate and potassium molybdate; the Sn atom source is stannous chloride; the W atom source is one or more of sodium tungstate, ammonium tungstate and potassium tungstate.

4. The method according to claim 1, wherein the method is characterized by, The titanium source in step (2) is one or more of titanyl sulfate, titanium sulfate, titanium tetrachloride and titanium trichloride.

5. The method according to claim 1, wherein the method is characterized by: The precipitating agent in step (2) is one or more of ammonia, sodium hydroxide, sodium carbonate and sodium bicarbonate.

6. The method according to claim 1, wherein the method is characterized by, The dissolving agent in step (2) is one or more of hydrogen peroxide, sodium peroxide and potassium peroxide.

7. The method according to claim 1, wherein the method is characterized by, The crystallization growth regulator in step (3) is one or more of hydrazine hydrate, sodium borohydride, sodium peroxide and peroxoacetic acid, and the addition amount is 0.1% to 20% of the molar amount of titanium atoms.

8. The method according to claim 1, wherein the method is characterized by, The temperature of the hydrothermal reaction in step (3) is 80°C to 200°C, and the hydrothermal time is 4h to 72h.

9. The method according to claim 1, wherein the method is characterized by, The calculation in step (1) employs density functional theory, and the {101} facet / {001} facet exposure ratio is predicted by combining Wulff rule, so as to determine the theoretical doping parameter required to achieve the exposure ratio of the {101} facet / {001} facet.

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