High-stability tungsten oxide target material for intelligent dimming glass and preparation method of high-stability tungsten oxide target material

Abstract

The invention relates to the technical field of target materials, in particular to a high-stability tungsten oxide target material for intelligent dimming glass and a preparation method of the high-stability tungsten oxide target material for the intelligent dimming glass. The modified element is at least one of Nb, Ta and Sn; the doping amount of the modified element is 0.5%-5% of the mass of the tungsten oxide matrix. The doping elements (such as Nb < 5 + > and Sn < 4 + >) are similar to W < 6 + > in radius, a stable solid solution is formed, lattice distortion in the ion circulation process is inhibited, microcracks are reduced, and conductivity is enhanced.

Description

Technical Field

[0001] This invention relates to the field of target technology, specifically to a highly stable tungsten oxide target for smart dimming glass and its preparation method. Background Technology

[0002] Smart dimming glass, as a novel functional material, can reversibly adjust its light transmittance according to changes in the external environment or human control, and is widely used in building doors and windows, automotive sunroofs, display devices, and other fields. Electrochromism is one of the core working principles of smart dimming glass, and tungsten oxide (WO3) is widely used as the core material of the electrochromic layer due to its excellent electrochromic properties.

[0003] Tungsten oxide electrochromic layers are typically fabricated using magnetron sputtering. The performance of the tungsten oxide target used in sputtering directly determines the quality of the electrochromic layer, thus affecting the lifespan and performance stability of smart dimming glass. During the electrochromic process, the tungsten oxide layer needs to undergo repeated H... + Li + The injection and extraction of plasma causes the tungsten oxide crystal structure to expand and contract in volume. Long-term cycling can easily lead to structural damage and cracks, which in turn reduces the conductivity of the electrochromic layer, degrades the dimming performance, and ultimately shortens the service life of the smart dimming glass.

[0004] In existing technologies, doping with metal elements is commonly used to improve the conductivity of tungsten oxide targets. However, simple doping often leads to a decrease in the structural stability of the target, making structural damage during ion cycling more prominent. Furthermore, current fabrication processes lack sufficient control over the density and grain size of the target, further exacerbating performance degradation during ion cycling. Therefore, developing a tungsten oxide target that combines high conductivity with excellent ion implantation / extraction cycle stability is of great significance for extending the lifespan of smart dimming glass. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a highly stable tungsten oxide target for smart dimming glass and its preparation method, thereby solving the problems mentioned in the background art.

[0006] The present invention solves the technical problem by adopting the following technical solution: This invention provides a highly stable tungsten oxide target material for smart dimming glass. The target material uses tungsten oxide as a matrix and is doped with modifying elements and a modifying Ti agent. The modifying element is at least one of Nb, Ta, and Sn, and the doping amount is 0.5% to 5% of the tungsten oxide matrix mass. The amount of the modifying Ti agent added is 2% to 5% of the tungsten oxide matrix mass, and it is prepared by ball milling, filtration, and drying of Ti powder and a modifier containing yttrium oxide, zirconium powder, chitosan solution, and sodium alginate powder.

[0007] Preferably, the doping amount of the modifying element is 1% to 3% of the mass of the tungsten oxide matrix; the modifying element is preferably a composite doping of Nb and Sn, with a mass ratio of 1:1 to 3:1.

[0008] Preferably, the grain size of the target material is 0.5~2μm, and the grain size distribution is uniform with a grain size difference ≤0.8μm.

[0009] The present invention also provides a method for preparing a highly stable tungsten oxide target material, such as for use in smart dimming glass, comprising the following steps: (1) Raw material pretreatment: Tungsten oxide powder and modified element compound powder are dried separately at a temperature of 80~120℃ for 2~4h; the modified element compound is at least one of oxide, nitrate or chloride. (2) Mixing and ball milling: The pretreated tungsten oxide powder and modified element compound powder are added to the ball milling equipment, along with dispersant and ball milling media, and ball milling is carried out. The ball milling speed is 200~400 r / min, and the ball milling time is 4~12 h to obtain a uniform mixed powder. The ball milling equipment is a planetary ball mill (such as QM-3SP4 type). (3) Drying and granulation: The ball-milled mixed powder is dried to remove the dispersant and moisture. The drying temperature is 100~150℃ and the drying time is 2~6h. Then, granulation is carried out to obtain particles with a particle size of 50~200μm. Spray granulation is adopted, the binder is a 5% polyvinyl alcohol (PVA) solution, the spray pressure is 0.3-0.5MPa, the inlet temperature is 180-200℃ and the outlet temperature is 80~100℃. (4) Molding: The granulated particles are loaded into the mold and cold isostatic pressing is used. The molding pressure is 150~300MPa and the holding time is 5~20min to obtain the target blank. (5) Sintering: The target blank is placed in a sintering furnace and degreased first. The degreasing temperature is 300~500℃ and the holding time is 2~5h. Then the temperature is raised to the sintering temperature and sintered in an inert atmosphere or a reducing atmosphere. The sintering temperature is 1200~1500℃ and the holding time is 4~10h. After cooling, a high-stability tungsten oxide target is obtained.

[0010] Preferably, in step (2), the dispersant is one of anhydrous ethanol and acetone, and the mass ratio of the dispersant to the powder is 0.5:1 to 1.5:1; the ball milling medium is zirconia balls, and the ball-to-powder ratio is 5:1 to 10:1. In step (5), the inert atmosphere is either argon or nitrogen; the reducing atmosphere is a mixture of hydrogen and argon, wherein the volume fraction of hydrogen is 5% to 20%. The degreasing heating rate is 5~10℃ / min, the sintering heating rate is 10~20℃ / min, and the cooling rate is 5~15℃ / min; the ball milling process adopts intermittent ball milling, with a 30-minute stop after every 2 hours of ball milling, in order to control the temperature during the ball milling process to not exceed 60℃. In step (4), a release agent is pre-applied to the inner wall of the mold, which is graphite powder or boron nitride powder.

[0011] Preferably, in step (2), 2-5% by weight of a modifier Ti agent is added to the tungsten oxide powder; The preparation method of the modified Ti agent is as follows: Ti powder is preheated at 60-65℃ for 1 hour to obtain preheated Ti powder. The preheated Ti powder and modifier are ball-milled at a weight ratio of (11-15):5. After ball milling, the mixture is filtered and dried. The filtration pressure is 0.1-0.3MPa, the drying temperature is 100-120℃, and the drying time is 2-3 hours to ensure that the moisture content is less than 0.5% to obtain the modified Ti agent.

[0012] Preferably, the ball milling speed for the ball milling improvement treatment is 1000-1500 r / min, and the ball milling time is 2 h.

[0013] Preferably, the modifier comprises 2-5 parts yttrium oxide, 1-3 parts zirconium powder, 5-8 parts chitosan solution, and 2-3 parts sodium alginate powder.

[0014] Preferably, the chitosan solution has a mass fraction of 2-5%.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The synergistic enhancement effect of doping elements in this invention improves structural stability: doping elements (such as Nb) 5+ Sn 4+ ) and W 6+Similar radii form a stable solid solution, suppressing lattice distortion during ion cycling and reducing microcrack formation; enhanced conductivity: doping introduces additional electrons, increasing carrier concentration, significantly improving conductivity, reducing driving voltage, and shortening response time; improved fatigue resistance: composite doping (such as Nb-Sn) produces a synergistic effect, enhancing grain boundary bonding, improving resistance to volume expansion / contraction, and extending cycle life; multiple benefits of modified Ti agents; microstructure refinement: uniform distribution of yttrium oxide and zirconium powder hinders abnormal grain growth, obtaining a uniform fine-grained microstructure of 0.5~2μm, improving structural stability; toughening and reinforcement: Ti and tungsten oxide form an interfacial bond, improving brittleness and enhancing resistance to deformation; zirconium powder phase transformation toughening further enhances toughness; enhanced sintering activity: modified Ti agents lower the sintering temperature and increase density; chitosan and sodium alginate act as dispersants, ensuring uniform component distribution and avoiding local defects. Detailed Implementation

[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to specific examples. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] This embodiment provides a highly stable tungsten oxide target material for smart dimming glass, wherein the target material is based on tungsten oxide and doped with modifying elements; The modifying element is at least one of Nb, Ta, and Sn; the doping amount of the modifying element is 0.5% to 5% of the mass of the tungsten oxide matrix.

[0018] In this embodiment, the doping amount of the modifying element is 1% to 3% of the mass of the tungsten oxide matrix; the modifying element is a composite doping of Nb and Sn, with a mass ratio of 1:1 to 3:1.

[0019] The target material in this embodiment has a grain size of 0.5~2μm and a uniform grain size distribution with a grain size difference of ≤0.8μm.

[0020] This embodiment provides a method for preparing a highly stable tungsten oxide target material, such as for use in smart dimming glass, comprising the following steps: (1) Raw material pretreatment: Tungsten oxide powder and modified element compound powder are dried separately at a temperature of 80~120℃ for 2~4h; the modified element compound is at least one of oxide, nitrate or chloride. (2) Mixing and ball milling: The pretreated tungsten oxide powder and modified element compound powder are added to the ball milling equipment, along with dispersant and ball milling media, and ball milling is carried out. The ball milling speed is 200~400 r / min, and the ball milling time is 4~12 h to obtain a uniform mixed powder. (3) Drying and granulation: The ball-milled mixed powder is dried to remove the dispersant and moisture. The drying temperature is 100~150℃ and the drying time is 2~6h. Then, it is granulated to obtain particles with a particle size of 50~200μm. (4) Molding: The granulated particles are loaded into the mold and cold isostatic pressing is used. The molding pressure is 150~300MPa and the holding time is 5~20min to obtain the target blank. (5) Sintering: The target blank is placed in a sintering furnace and degreased first. The degreasing temperature is 300~500℃ and the holding time is 2~5h. Then the temperature is raised to the sintering temperature and sintered in an inert atmosphere or a reducing atmosphere. The sintering temperature is 1200~1500℃ and the holding time is 4~10h. After cooling, a high-stability tungsten oxide target is obtained.

[0021] In step (2) of this embodiment, the dispersant is one of anhydrous ethanol and acetone, and the mass ratio of the dispersant to the powder is 0.5:1 to 1.5:1; the ball milling medium is zirconia balls, and the ball-to-powder ratio is 5:1 to 10:1. In step (5), the inert atmosphere is either argon or nitrogen; the reducing atmosphere is a mixture of hydrogen and argon, wherein the volume fraction of hydrogen is 5% to 20%. The degreasing heating rate is 5~10℃ / min, the sintering heating rate is 10~20℃ / min, and the cooling rate is 5~15℃ / min; the ball milling process adopts intermittent ball milling, with a 30-minute stop after every 2 hours of ball milling, in order to control the temperature during the ball milling process to not exceed 60℃. In step (4), a release agent is pre-applied to the inner wall of the mold, which is graphite powder or boron nitride powder.

[0022] In step (2) of this embodiment, 2-5% of a modifier Ti agent is also added to the tungsten oxide powder; The preparation method of the modified Ti agent is as follows: Ti powder was preheated at 60-65℃ for 1 hour to obtain preheated Ti powder. The preheated Ti powder and modifier were ball-milled at a weight ratio of (11-15):5. After ball milling, the mixture was filtered and dried to obtain the modified Ti agent.

[0023] In this embodiment, the ball milling speed for the improved ball milling treatment is 1000-1500 r / min, and the ball milling time is 2 hours.

[0024] The modifier in this embodiment consists of 2-5 parts yttrium oxide, 1-3 parts zirconium powder, 5-8 parts chitosan solution, and 2-3 parts sodium alginate powder.

[0025] The chitosan solution in this embodiment has a mass fraction of 2-5%.

[0026] Example 1. This embodiment provides a highly stable tungsten oxide target material for smart dimming glass, wherein the target material is based on tungsten oxide and doped with modifying elements; The doping amount of the modified element is 0.5% of the mass of the tungsten oxide matrix.

[0027] In this embodiment, the doping amount of the modifying element is 1% of the mass of the tungsten oxide matrix; the modifying element is a composite doping of Nb and Sn, with a mass ratio of 1:1.

[0028] The target material in this embodiment has a grain size of 0.5 μm and a uniform grain size distribution with a grain size difference of ≤0.8 μm.

[0029] This embodiment provides a method for preparing a highly stable tungsten oxide target material, such as for use in smart dimming glass, comprising the following steps: (1) Raw material pretreatment: Tungsten oxide powder and modified element compound powder are dried separately at 80°C for 2 hours; the modified element compound is an oxide. (2) Ball milling: The pretreated tungsten oxide powder and the modified element compound powder are added to the ball milling equipment, along with the dispersant and ball milling media. The ball milling is carried out at a speed of 200 r / min and a time of 4 h to obtain a uniform mixed powder. (3) Drying and granulation: The ball-milled mixed powder is dried to remove the dispersant and moisture. The drying temperature is 100℃ and the drying time is 2h. Then, it is granulated to obtain particles with a particle size of 50μm. (4) Molding: The granulated particles are loaded into the mold and cold isostatic pressing is used to obtain the target blank. The molding pressure is 150MPa and the holding time is 5min. (5) Sintering: The target blank is placed in a sintering furnace and degreased first. The degreasing temperature is 300℃ and the holding time is 2h. Then the temperature is raised to the sintering temperature and sintered in an inert atmosphere or a reducing atmosphere. The sintering temperature is 1200℃ and the holding time is 4h. After cooling, a high-stability tungsten oxide target is obtained.

[0030] In step (2) of this embodiment, the dispersant is anhydrous ethanol, and the mass ratio of the dispersant to the powder is 0.5:1; the ball milling media is zirconia balls, and the ball-to-powder ratio is 5:1. In step (5), the inert atmosphere is argon; the reducing atmosphere is a mixture of hydrogen and argon, wherein the volume fraction of hydrogen is 5%. The degreasing heating rate is 5℃ / min, the sintering heating rate is 10℃ / min, and the cooling rate is 5℃ / min. The ball milling process adopts intermittent ball milling, with a 30-minute stop every 2 hours of ball milling, in order to control the temperature during the ball milling process to not exceed 60℃. In step (4), a release agent is pre-applied to the inner wall of the mold, which is graphite powder or boron nitride powder.

[0031] In step (2) of this embodiment, 2% of a modified Ti agent is also added to the tungsten oxide powder; The preparation method of the modified Ti agent is as follows: Ti powder was preheated at 60℃ for 1 hour to obtain preheated Ti powder. The preheated Ti powder and modifier were ball-milled at a weight ratio of 11:5. After ball milling, the mixture was filtered and dried to obtain the modified Ti agent.

[0032] In this embodiment, the ball milling speed for the improved ball milling process is 1000 r / min, and the ball milling time is 2 hours.

[0033] The modifier in this embodiment consists of 2 parts yttrium oxide, 1 part zirconium powder, 5 parts chitosan solution, and 2 parts sodium alginate powder.

[0034] The chitosan solution in this embodiment has a mass fraction of 2%.

[0035] Example 2. This embodiment provides a highly stable tungsten oxide target material for smart dimming glass, wherein the target material is based on tungsten oxide and doped with modifying elements; The amount of the modified element is 5% of the mass of the tungsten oxide matrix.

[0036] In this embodiment, the doping amount of the modifying element is 3% of the mass of the tungsten oxide matrix; the modifying element is a composite doping of Nb and Sn, with a mass ratio of 1:1 to 3:1.

[0037] The target material in this embodiment has a grain size of 2μm and a uniform grain size distribution with a grain size difference of ≤0.8μm.

[0038] This embodiment provides a method for preparing a highly stable tungsten oxide target material, such as for use in smart dimming glass, comprising the following steps: (1) Raw material pretreatment: Tungsten oxide powder and modified element compound powder are dried separately at 120°C for 4 hours; the modified element compound is at least one of oxide, nitrate or chloride. (2) Ball milling: The pretreated tungsten oxide powder and the modified element compound powder are added to the ball milling equipment, along with the dispersant and ball milling media. The ball milling is carried out at a speed of 400 r / min and a time of 12 h to obtain a uniform mixed powder. (3) Drying and granulation: The ball-milled mixed powder is dried to remove the dispersant and moisture. The drying temperature is 150℃ and the drying time is 6h. Then, it is granulated to obtain particles with a particle size of 200μm. (4) Molding: The granulated particles are loaded into the mold and cold isostatic pressing is used to obtain the target blank. The molding pressure is 300MPa and the holding time is 20min. (5) Sintering: The target blank is placed in a sintering furnace and degreased first. The degreasing temperature is 500℃ and the holding time is 5h. Then the temperature is raised to the sintering temperature and sintered in an inert atmosphere or a reducing atmosphere. The sintering temperature is 1500℃ and the holding time is 10h. After cooling, a high-stability tungsten oxide target is obtained.

[0039] In step (2) of this embodiment, the dispersant is anhydrous ethanol, and the mass ratio of the dispersant to the powder is 1.5:1; the ball milling medium is zirconia balls, and the ball-to-powder ratio is 10:1. In step (5), the inert atmosphere is either argon or nitrogen; the reducing atmosphere is a mixture of hydrogen and argon, wherein the volume fraction of hydrogen is 20%. The degreasing heating rate is 10℃ / min, the sintering heating rate is 20℃ / min, and the cooling rate is 15℃ / min. The ball milling process adopts intermittent ball milling, with a 30-minute stop every 2 hours of ball milling, in order to control the temperature during the ball milling process to not exceed 60℃. In step (4), a release agent is pre-applied to the inner wall of the mold, which is graphite powder or boron nitride powder.

[0040] In step (2) of this embodiment, 5% of a modifier Ti is added to the tungsten oxide powder; The preparation method of the modified Ti agent is as follows: Ti powder was preheated at 65°C for 1 hour to obtain preheated Ti powder. The preheated Ti powder and modifier were ball-milled at a weight ratio of 15:5. After ball milling, the mixture was filtered and dried to obtain the modified Ti agent.

[0041] In this embodiment, the ball milling speed for the improved ball milling process is 1500 r / min, and the ball milling time is 2 hours.

[0042] The modifier in this embodiment consists of 5 parts yttrium oxide, 3 parts zirconium powder, 8 parts chitosan solution, and 3 parts sodium alginate powder.

[0043] The chitosan solution in this embodiment has a mass fraction of 5%.

[0044] Example 3. This embodiment provides a highly stable tungsten oxide target material for smart dimming glass, wherein the target material is based on tungsten oxide and doped with modifying elements; The amount of the modified element is 2% of the mass of the tungsten oxide matrix.

[0045] In this embodiment, the doping amount of the modifying element is 2% of the mass of the tungsten oxide matrix; the modifying element is a composite doping of Nb and Sn, with a mass ratio of 2:1.

[0046] The target material in this embodiment has a grain size of 1 μm and a uniform grain size distribution with a grain size difference of ≤0.8 μm.

[0047] This embodiment provides a method for preparing a highly stable tungsten oxide target material, such as for use in smart dimming glass, comprising the following steps: (1) Raw material pretreatment: Tungsten oxide powder and modified element compound powder are dried separately at 100°C for 3 hours; the modified element compound is at least one of oxide, nitrate or chloride. (2) Ball milling: The pretreated tungsten oxide powder and the modified element compound powder are added to the ball milling equipment, along with the dispersant and ball milling media. The ball milling is carried out at a speed of 300 r / min and a time of 8 h to obtain a uniform mixed powder. (3) Drying and granulation: The ball-milled mixed powder is dried to remove the dispersant and moisture. The drying temperature is 125℃ and the drying time is 4h. Then, it is granulated to obtain particles with a particle size of 100μm. (4) Molding: The granulated particles are loaded into the mold and cold isostatic pressing is used to obtain the target blank. The molding pressure is 200MPa and the holding time is 10min. (5) Sintering: The target blank is placed in a sintering furnace and degreased first. The degreasing temperature is 400℃ and the holding time is 3.5h. Then the temperature is raised to the sintering temperature and sintered in an inert atmosphere or a reducing atmosphere. The sintering temperature is 1350℃ and the holding time is 7h. After cooling, a high-stability tungsten oxide target is obtained.

[0048] In step (2) of this embodiment, the dispersant is anhydrous ethanol, and the mass ratio of the dispersant to the powder is 1:1; the ball milling medium is zirconia balls, and the ball-to-powder ratio is 7:1. In step (5), the inert atmosphere is argon; the reducing atmosphere is a mixture of hydrogen and argon, wherein the volume fraction of hydrogen is 12%. The degreasing heating rate is 7.5℃ / min, the sintering heating rate is 15℃ / min, and the cooling rate is 10℃ / min. The ball milling process adopts intermittent ball milling, with a 30-minute stop every 2 hours of ball milling, in order to control the temperature during the ball milling process to not exceed 60℃. In step (4), a release agent is pre-applied to the inner wall of the mold, which is graphite powder or boron nitride powder.

[0049] In step (2) of this embodiment, 3.5% of a modified Ti agent is also added to the tungsten oxide powder; The preparation method of the modified Ti agent is as follows: Ti powder was preheated at 62℃ for 1 hour to obtain preheated Ti powder. The preheated Ti powder and modifier were ball-milled at a weight ratio of 13:5. After ball milling, the mixture was filtered and dried to obtain the modified Ti agent.

[0050] In this embodiment, the ball milling speed for the improved ball milling process is 1250 r / min, and the ball milling time is 2 hours.

[0051] The modifier in this embodiment is 3.5 parts yttrium oxide, 2 parts zirconium powder, 6.5 parts chitosan solution, and 2.5 parts sodium alginate powder.

[0052] The chitosan solution in this embodiment has a mass fraction of 3.5%.

[0053] Comparative Example 1. Unlike Example 3, no modified Ti agent was added.

[0054] Comparative Example 2. Unlike Example 3, no modifier was added during the preparation of the modified Ti agent.

[0055] Comparative Example 3. Unlike Example 3, yttrium oxide was not added to the modifier.

[0056] Comparative Example 4. Unlike Example 3, zirconium powder was not added to the modifier.

[0057] Comparative Example 5. Unlike Example 3, sodium alginate powder was not added during the preparation of the modifier.

[0058] The products of Examples 1-3 and Comparative Examples 1-5 were subjected to performance tests. The conductivity was tested according to GB / T-32791-2016; the density was measured using the Archimedes method (GB / T2680-2021); the electrochromic response time was measured at a wavelength of 550 nm, and the electrolyte was 1 mol / L LiClO. 4- The propylene carbonate solution was tested with an applied voltage of ±1.5V, and the results are as follows:

[0059] From Examples 1-3 and Comparative Examples 1-5, it can be seen that the product of the present invention can achieve coordinated and comprehensive improvement in product performance. When no modified Ti agent is added to the product, the performance of the product deteriorates significantly. When no modifier is added in the preparation of the modified Ti agent, when yttrium oxide is not added to the modifier, when zirconium powder is not added to the modifier, and when sodium alginate powder is not added in the preparation of the modifier, the performance of the product deteriorates to varying degrees. Only the modified Ti agent obtained by the method of the present invention has the most significant performance effect.

[0060] 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 the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0061] 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 highly stable tungsten oxide target material for smart dimming glass, characterized in that, The target material uses tungsten oxide as a matrix and is doped with modifying elements and a modifying Ti agent. The modifying element is at least one of Nb, Ta, and Sn, and the doping amount is 0.5% to 5% of the tungsten oxide matrix mass. The amount of the modifying Ti agent added is 2% to 5% of the tungsten oxide matrix mass, and it is prepared by ball milling, filtration, and drying of Ti powder and a modifier containing yttrium oxide, zirconium powder, chitosan solution, and sodium alginate powder.

2. The high-stability tungsten oxide target material for smart dimming glass according to claim 1, characterized in that, The doping amount of the modified element is 1% to 3% of the mass of the tungsten oxide matrix; and the modified element is preferably a composite doping of Nb and Sn, with a mass ratio of 1:1 to 3:

1.

3. The high-stability tungsten oxide target material for smart dimming glass according to claim 1, characterized in that, The target material has a grain size of 0.5~2μm and a uniform grain size distribution with a grain size difference of ≤0.8μm.

4. A method for preparing a highly stable tungsten oxide target for smart dimming glass as described in any one of claims 1 to 3, characterized in that, Includes the following steps: (1) Raw material pretreatment: Tungsten oxide powder and modified element compound powder are dried separately at a temperature of 80~120℃ for 2~4h; the modified element compound is at least one of oxide, nitrate or chloride. (2) Mixing and ball milling: The pretreated tungsten oxide powder and modified element compound powder are added to the ball milling equipment, along with dispersant and ball milling media, and ball milling is carried out. The ball milling speed is 200~400 r / min, and the ball milling time is 4~12 h to obtain a uniform mixed powder. (3) Drying and granulation: The ball-milled mixed powder is dried to remove the dispersant and moisture. The drying temperature is 100~150℃ and the drying time is 2~6h. Then, it is granulated to obtain particles with a particle size of 50~200μm. (4) Molding: The granulated particles are loaded into the mold and cold isostatic pressing is used. The molding pressure is 150~300MPa and the holding time is 5~20min to obtain the target blank. (5) Sintering: The target blank is placed in a sintering furnace and degreased first. The degreasing temperature is 300~500℃ and the holding time is 2~5h. Then the temperature is raised to the sintering temperature and sintered in an inert atmosphere or a reducing atmosphere. The sintering temperature is 1200~1500℃ and the holding time is 4~10h. After cooling, a high-stability tungsten oxide target is obtained.

5. The preparation method according to claim 4, characterized in that, In step (2), the dispersant is one of anhydrous ethanol and acetone, and the mass ratio of the dispersant to the powder is 0.5:1 to 1.5:1; the ball milling medium is zirconia balls, and the ball-to-powder ratio is 5:1 to 10:

1. In step (5), the inert atmosphere is either argon or nitrogen; the reducing atmosphere is a mixture of hydrogen and argon, wherein the volume fraction of hydrogen is 5% to 20%. The degreasing heating rate is 5~10℃ / min, the sintering heating rate is 10~20℃ / min, and the cooling rate is 5~15℃ / min; the ball milling process adopts intermittent ball milling, with a 30-minute stop after every 2 hours of ball milling, in order to control the temperature during the ball milling process to not exceed 60℃. In step (4), a release agent is pre-applied to the inner wall of the mold, which is graphite powder or boron nitride powder.

6. The preparation method according to claim 5, characterized in that, In step (2), 2-5% by weight of a modifier Ti agent is also added to the tungsten oxide powder; The preparation method of the modified Ti agent is as follows: Ti powder was preheated at 60-65℃ for 1 hour to obtain preheated Ti powder. The preheated Ti powder and modifier were ball-milled at a weight ratio of (11-15):

5. After ball milling, the mixture was filtered and dried to obtain the modified Ti agent.

7. The preparation method according to claim 6, characterized in that, The ball milling speed for the improved treatment was 1000-1500 r / min, and the ball milling time was 2 h.

8. The preparation method according to claim 6, characterized in that, The modifier consists of 2-5 parts yttrium oxide, 1-3 parts zirconium powder, 5-8 parts chitosan solution, and 2-3 parts sodium alginate powder.

9. The preparation method according to claim 8, characterized in that, The chitosan solution has a mass fraction of 2-5%.

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