Highly distorted surface nanocrystalline TiO x Modified layer and method for producing the same

Abstract

The application relates to a high-distortion-state surface nanocrystallization TiOx modification layer and a preparation method thereof, and belongs to the field of material engineering. The outermost layer of the high-distortion-state surface nanocrystallization TiOx modification layer is high-distortion-state amorphous; the middle layer is a rutile TiO2 layer; and the innermost layer is a self-nanocrystallization titanium alloy. The preparation method comprises the following steps: forming a nanocrystalline layer on the surface of a substrate through ball milling, taking the substrate with the nanocrystalline layer as an anode plate, taking a stainless steel plate as a cathode plate, and performing electrochemical oxidation in an electrolyte to obtain a substrate with two modification layers; and performing chemical reduction on the substrate with the two modification layers to prepare the high-distortion-state surface nanocrystallization TiOx modification layer which is well combined with the substrate and has high visible light response. The high-distortion-state surface nanocrystallization TiOx modification layer has good degradation ability of organic dyes under visible light, and also has good sterilization effect in low-concentration biological wastewater.

Description

Technical Field

[0001] This invention relates to a high-distortion surface nano-modified TiOx layer and its preparation method, belonging to the field of materials engineering. Background Technology

[0002] TiO2 possesses advantages such as being biologically non-toxic, chemically stable, and causing no secondary pollution, leading to its widespread research in photocatalytic wastewater treatment. However, TiO2 has a relatively wide band gap (≥3.0 eV), corresponding to a narrow light absorption wavelength range. It can only absorb ultraviolet light with wavelengths less than 387 nm, failing to utilize the visible light portion, which accounts for approximately 50% of sunlight. Furthermore, the photogenerated electron-hole pairs generated after TiO2 absorbs sunlight are prone to recombination in the bulk phase, resulting in low photocatalytic efficiency. Surface-distorted TiO2 is a self-doped photocatalyst that has been extensively studied in recent years. Its core is crystalline titanium dioxide, while the outer shell contains a large amount of Ti. 3+ and V o 2- The amorphous structure of TiO2, with its functionalized outer shell that transforms white TiO2 into a darker color, results in a surface-distorted structure that absorbs up to 85% of sunlight. Under visible light irradiation, its degradation rate of organic pollutants is four times that of ordinary white TiO2. The excellent broad-spectrum absorption, stable physicochemical properties, and low electron-hole recombination rate enable the surface-distorted structure TiO2 to meet the requirements for efficient solar energy utilization. However, TiO2 typically exists as suspended particles in solution during reactions, which significantly affects the absorption of light by TiO2 particles and the depth of light irradiation. Furthermore, suspended particles tend to aggregate in aqueous solutions, making post-reaction recovery difficult. These unfavorable factors severely limit the practical application of TiO2 suspension systems. Summary of the Invention

[0003] To address the aforementioned problems, this invention proposes a high-distortion surface nano-modified TiOx layer and its preparation method. Using ordinary titanium alloy sheet as the substrate, this invention employs a three-step process—surface nano-sizing, electrochemical oxidation (micro-arc oxidation, anodic oxidation), and chemical reduction—to prepare a high-distortion surface nano-modified TiOx layer that exhibits good bonding with the substrate and high visible light response. This high-distortion surface nano-modified TiOx layer demonstrates excellent ability to degrade organic dyes under visible light and also exhibits good bactericidal effects in low-concentration biological wastewater.

[0004] The present invention discloses a high-distortion surface nano-sized TiOx modified layer, the structure of which is as follows: the innermost layer is closer to the substrate, the outermost layer is farther from the substrate, and an intermediate layer is disposed between the innermost layer and the outermost layer; wherein, the outermost layer of the high-distortion surface nano-sized TiOx modified layer is a high-distortion amorphous material; the intermediate layer of the high-distortion surface nano-sized TiOx modified layer is rutile phase TiO2; and the innermost layer of the high-distortion surface nano-sized TiOx modified layer is a self-nanosized titanium alloy.

[0005] Among them, the highly distorted surface nano-TiOx modified layer has a thickness of x<2.

[0006] The substrate is a common titanium alloy substrate.

[0007] The outermost layer has a thickness of 1-5 micrometers, the middle layer has a thickness of 1-25 micrometers, and the innermost layer has a thickness of 1-30 μm.

[0008] The outermost highly distorted amorphous layer exhibits a color or gradient color among light gray, yellowish brown, dark blue, and black, depending on the degree of O reduction in TiOx.

[0009] The method for preparing the high-distortion surface nano-sized TiOx modified layer of the present invention includes the following steps:

[0010] S1: Surface nanofiberization

[0011] (1) Clean the surface of the substrate to remove impurities and obtain a clean substrate;

[0012] (2) The clean substrate is ball-milled in an inert gas or vacuum environment at a ball milling speed of 850-900 rpm for 30-120 min to form a nanocrystalline layer with a thickness of 1-30 μm on the substrate surface.

[0013] In step S1(1), the substrate is selected from titanium alloy plates, and the thickness δ of the substrate is preferably 0.3-5mm.

[0014] In step S1(1), impurity removal is achieved by sanding to remove the surface acidified film, and cleaning is achieved by ultrasonic cleaning with acetone to remove surface dirt.

[0015] In step S1(1), ball milling is performed in a ball mill with an inverted figure-eight motion path, preferably dry ball milling. The ball mill used is a SPEX ball mill, and the ball-to-material ratio is (6-7):1 by mass. The particle size of the ball milling media is [missing information]. The milling media are one or more of the following: iron-based microspheres, iron-based spheres, iron-based regular geometric shapes, iron-based irregular geometric shapes, titanium-based microspheres, titanium-based spheres, titanium-based regular geometric shapes, titanium-based irregular geometric shapes, cemented carbide microspheres, cemented carbide spheres, cemented carbide regular geometric shapes, and cemented carbide irregular geometric shapes.

[0016] In step S1(2), the inert gas is selected from Ar, He, Ne or N2.

[0017] S2: Electrochemical oxidation

[0018] (1) The substrate forming the nanocrystalline layer is used as the anode plate and the stainless steel plate is used as the cathode plate. The anode plate and the cathode plate are arranged in parallel face to face and immersed in the electrolyte. The horizontal distance between the cathode plate and the anode plate is 40-60 mm.

[0019] In step S2(1), the electrolyte in the electrolyte solution is selected from one or more of phosphate, hydrogen phosphate, and silicate, and the concentration of the electrolyte in the electrolyte solution is 10-20 g / L.

[0020] (2) Start the electrochemical oxidation power supply

[0021] Electrochemical oxidation power sources include micro-arc oxidation power sources or anodic oxidation power sources.

[0022] The micro-arc oxidation power supply has a control voltage of 300-400V and a current density of 8-12A / dm³. 2 The oxidation process was continued for 20-40 minutes. After the oxidation process was completed, the anode plate was removed, cleaned and dried, and a layer of white TiO2 was formed on the surface of the nanocrystalline layer of the substrate. After testing, the white TiO2 was found to be rutile phase TiO2; a substrate with two modified layers was obtained.

[0023] The anodizing power supply has a controlled voltage of 50-300V and a current density of 0.5-5A / dm³. 3 The oxidation process was continued for 5-30 minutes. After the oxidation process was completed, the anode plate was removed, cleaned and dried. A layer of grayish-white TiO2 was formed on the surface of the nanocrystalline layer of the substrate. After testing, the grayish-white TiO2 was found to be rutile phase TiO2. A substrate with two modified layers was obtained.

[0024] In step S2(2), the cleaning is performed using ultrasonic cleaning with acetone.

[0025] S3: Chemical reduction

[0026] (1) Place the two modified layers of substrate horizontally and spread a layer of ammonium salt powder evenly on the surface. Place it horizontally in the heating zone of the plasma CVD furnace near the plasma source (PE source) so that the surface of the two modified layers of substrate is parallel to the gas flow direction in the plasma CVD furnace and seal it.

[0027] In step S3(1), the thickness of the uniformly coated ammonium salt powder is 0.1-1 mm. The ammonium salt powder is selected from ammonium salt substances that can be decomposed into N2 and H2 by heat, and more specifically, one or more of (NH4)2CO3, CH3COONH4, and NH4Cl.

[0028] (2) Argon gas is continuously introduced into the sealed plasma CVD furnace to remove impurity gases in the sealed plasma CVD furnace. Argon gas is continuously introduced at a gas flow rate of 0.1-0.2 L / min, and the pressure of the sealed plasma CVD furnace is continuously controlled to be kept at <200 Pa.

[0029] (3) Heat the ammonium salt powder to 160-350℃ at a heating rate of 5-10℃ / min, so that the ammonium salt powder decomposes into H2, N2 and H2O;

[0030] Adjust the RF power supply to 300-600W to ionize the decomposed H2 and N2 plasmas. After the glow discharge stabilizes, keep it at that temperature for 0.5-8 hours.

[0031] (4) After the heat preservation is completed, the flow rate of argon gas is maintained until the furnace temperature of the heating furnace drops to room temperature, and the matrix of the nano-modified TiOx layer with high distortion surface is obtained.

[0032] In step S3, the degree of reduction of O in TiOx is determined by the holding time in step S3(3).

[0033] The present invention discloses a high-distortion surface nano-sized TiOx modified layer and its preparation method, the beneficial effects of which are as follows:

[0034] This invention uses ordinary titanium alloy sheet as a template and prepares the TiOx modified layer through three steps: surface self-nanoization, electrochemical oxidation, and plasma chemical reduction. The resulting highly distorted surface nano-modified TiOx layer has a dense and continuous gradient structure, with an outermost layer of highly distorted amorphous material, a middle layer of rutile TiO2, and an inner layer of self-nanosized titanium alloy. Compared with the white TiO2 coating prepared by ordinary electrochemical oxidation, it has a darker color and exhibits good ability to degrade organic pollutants under visible light irradiation. The substrate used in this invention is ordinary titanium alloy sheet, which is inexpensive and readily available. The equipment used is mature and stable, and the process is simple and easy to industrialize. In addition to degrading organic pollutants, the prepared highly distorted surface nano-modified TiOx modified layer also exhibits good bactericidal effects in biological wastewater.

[0035] In the ball milling process, this invention utilizes a ball mill to achieve an infinite motion path, allowing the grinding media to impact the titanium alloy surface in more random directions. This generates dislocation motions in random directions on the titanium alloy surface. Through the continuous accumulation of dislocation motions, the coarse grains on the titanium alloy surface are gradually refined into nanocrystals. By controlling the ball mill speed and milling time, the surface grain size and nanocrystalline layer thickness can be controlled.

[0036] The present invention controls parameters such as holding time, heating temperature, and plasma source power during the plasma chemical reduction process, enabling H2 and N2 to respectively complete the synergistic effect of oxygen atom reduction and nitrogen atom doping, thereby achieving the formation of highly distorted amorphous states. Attached Figure Description

[0037] Figure 1 A schematic diagram of a nano-TiOx modified layer structure with high distortion surface;

[0038] Figure 2 (a) is a macroscopic photograph of the surface of the original untreated titanium sheet in Example 1;

[0039] Figure 2 (b) is a macroscopic photograph of the surface of the titanium sheet after surface nano-sizing treatment in Example 1;

[0040] Figure 2 (c) is a macroscopic photograph of the surface of the titanium sheet after surface nano-treatment and micro-arc oxidation in Example 1;

[0041] Figure 2 (d) is a macroscopic photograph of the surface of the titanium sheet after surface nano-treatment, micro-arc oxidation, and chemical reduction treatment in Example 1.

[0042] Figure 3 This is a scanning electron microscope image of the surface of a nano-sized TiOx modified layer with high distortion surface in Example 1;

[0043] Figure 4 This is a cross-sectional scanning electron microscope image of a nano-sized TiOx modified layer with a highly distorted surface, as described in Example 1.

[0044] Figure 5 This is a transmission electron microscope image of the TiOx microstructure at the outermost layer of a highly distorted surface nano-modified TiOx layer, as observed in Example 1.

[0045] Figure 6 This is the X-ray diffraction pattern of the nano-sized TiOx modified layer with high distortion surface obtained in Example 1;

[0046] Figure 7This is the UV-Vis diffuse reflectance image of the highly distorted surface nano-sized TiOx modified layer prepared in Example 1;

[0047] Figure 8 The graphs show the degradation curves of Rhodamine-B solution under UV + Visible irradiation for the ordinary white TiO2 modified layer and the highly distorted surface nano-TiOx modified layer prepared in Test Example 1.

[0048] Figure 9 The graphs show the degradation curves of Rhodamine-B solution under visible light irradiation for the ordinary white TiO2 modified layer and the highly distorted surface nano-TiOx modified layer prepared in Test Example 2. Detailed Implementation

[0049] The present invention will be further described in detail below with reference to the embodiments.

[0050] Example 1

[0051] The δ3mm industrial pure titanium sheet produced by Shaanxi Baotai Group Co., Ltd. was wire-cut into 5mm×5mm titanium sheets using electrical discharge machining. A macroscopic photograph of the surface is shown below. Figure 2 (a) and then use 240 repeatedly. # 600 # 1200 # The surface of the titanium sheet was sanded to remove the surface acid film, and finally ultrasonically cleaned three times with acetone to remove surface dirt; the cleaned titanium sheet was then attached to the side wall of a 0.2-liter WC grinding jar, and 60 pieces were placed on it. GCr15 steel balls were loaded into a 0.2-liter WC grinding jar and sealed with Ar gas. The Ar-sealed grinding jar was then fixed on a SPEX-8000M ball mill and continuously ground at 875 rpm for 90 minutes. This process produced a titanium nanocrystalline layer with a thickness of 30 μm on the surface of the titanium sheet. Macroscopic images of the surface are shown below. Figure 2 (b);

[0052] The prepared nanocrystalline titanium sheet was fixed with a titanium alloy fixture and used as the anode plate. An 80mm×100mm×3mm stainless steel plate was used as the cathode plate. The anode and cathode plates were then completely immersed in a 15g / L Na3PO4 electrolyte and arranged in parallel face-to-face with a distance of 50mm between them. The micro-arc oxidation power supply was started and the voltage was controlled at 350V and the current density at 10A / dm³. 2 After continuous oxidation treatment for 30 minutes, the power was turned off and the sample was removed. After ultrasonic cleaning with acetone and drying, a titanium sheet with a white TiO2 modified layer was obtained. A macroscopic photograph of its surface is shown below. Figure 2 (c);

[0053] After uniformly coating the surface of the titanium sheet with a 0.3 mm thick layer of (NH4)2CO3 white powder, the sheet is placed horizontally in the heating zone of the PECVD furnace near the PE source, with its surface parallel to the gas flow direction. The furnace body is then sealed. Argon gas is continuously introduced into the sealed furnace chamber at a flow rate of 1 L / min for 10 min to remove impurity gases from the furnace chamber. After venting, argon gas was continuously introduced at a rate of 0.1 L / min, and the furnace was slowly heated to 200°C at a rate of 6°C / min to allow (NH4)2CO3 to slowly decompose into H2, N2, and H2O. Once (NH4)2CO3 began to decompose slowly, the radio frequency power supply was turned on and the power was adjusted to 450W to ionize H2 and N2 plasmas. After the glow discharge stabilized, the furnace was held at this temperature for 3 hours. Throughout the process, the furnace pressure was maintained below 200 Pa by controlling the tail valve. After the holding period, the radio frequency power supply was turned off, but the gas flow rate was kept constant. Once the furnace temperature dropped to room temperature, the gas supply was turned off, the tail valve was opened, and the titanium sheet with the highly distorted surface nano-modified TiOx layer was removed. The schematic diagram of the highly distorted surface nano-modified TiOx layer structure is shown below. Figure 1 ,from Figure 1 It can be seen that the structure of the nano-sized TiOx modified layer with high distortion surface is composed of high distortion amorphous phase, rutile phase TiO2, self-nanosized titanium alloy, and ordinary titanium alloy matrix from the outside to the inside.

[0054] The prepared highly distorted surface nano-modified TiOx layer appears nearly black, and its macroscopic surface photograph is shown below. Figure 2 (d), from Figure 2 It can be seen that after the original titanium substrate was treated with surface nano-sizing, the surface became rough and uneven. After micro-arc oxidation, it turned white, and after plasma chemical reduction, it turned nearly black.

[0055] The prepared high-distortion surface nano-modified TiOx layer was observed, and its surface scanning electron microscope image is shown below. Figure 3 ,from Figure 3 It can be seen that the surface of the nano-sized TiOx modified layer with high distortion is covered with honeycomb-like pores; cross-sectional scanning electron microscope images are shown below. Figure 4 ,from Figure 4 It can be seen that the thickness of the nano-modified TiOx layer with high distortion surface is 30-35 μm; the transmission electron microscopy image of the TiOx microstructure at the outermost layer of the nano-modified TiOx layer with high distortion surface is shown in the figure. Figure 5 ,from Figure 5 It can be seen that the TiO2 particles on the outermost surface of the nano-sized TiOx modified layer with high distortion exhibit an obvious high distortion amorphous structure;

[0056] X-ray diffraction pattern of the nano-sized TiOx modified layer on the highly distorted surface is shown below. Figure 6 ,from Figure 6 It can be seen that the main components of the nano-sized TiOx modified layer with high distortion surface are TiO2 and titanium.

[0057] Example 2

[0058] The specific implementation method is the same as in Example 1, except that the different heat preservation time results in different product appearance colors, which affects the absorbance performance of the product in the visible spectrum region. Specifically, after (NH4)2CO3 begins to slowly decompose, the radio frequency power supply is turned on and the power is adjusted to 450W to ionize H2 and N2 plasma. After the glow discharge stabilizes, the heat preservation is continued for 1 hour. Throughout the process, the furnace pressure is controlled by the tail valve to always maintain <200Pa. After the heat preservation is completed, the radio frequency power supply is turned off, but the gas flow rate is kept constant. After the furnace temperature drops to room temperature, the gas source is turned off, the tail valve is opened, and the titanium sheet with the nano-modified TiOx layer with high distortion surface is taken out. Its appearance color is dark gray.

[0059] Example 3

[0060] The specific implementation method is the same as in Example 1, except that the different heating temperatures result in different product appearance colors, which affect the absorbance of the product in the visible spectrum. Specifically, after the exhaust is completed, argon gas is continuously introduced at a rate of 0.1 L / min, and the furnace body is slowly heated to 350°C at a heating rate of 6°C / min so that (NH4)2CO3 can be rapidly decomposed into H2, N2, and H2O. After (NH4)2CO3 begins to decompose, the radio frequency power supply is turned on and the power is adjusted to 450W to ionize H2 and N2 plasma. After the glow discharge stabilizes, the temperature is maintained for another 1 hour. Throughout the process, the furnace pressure is controlled by the tail valve to always maintain <200Pa. After the temperature maintenance is completed, the radio frequency power supply is turned off, but the gas flow rate is kept constant. After the furnace temperature drops to room temperature, the gas source is turned off, the tail valve is opened, and the titanium sheet with the nano-modified TiOx layer with a high distortion surface is taken out. Its appearance color is nearly black.

[0061] Example 4

[0062] The specific implementation method is the same as in Example 1, except that the different radio frequency power supply and power adjustment result in different product appearance colors, which affect the absorbance performance of the product in the visible spectrum region. Specifically, after (NH4)2CO3 begins to slowly decompose, the radio frequency power supply is turned on and the power is adjusted to 350W to ionize H2 and N2 plasma. After the glow discharge stabilizes, the temperature is maintained for 3 hours. Throughout the process, the furnace pressure is controlled by the tail valve to always maintain <200Pa. After the temperature maintenance is completed, the radio frequency power supply is turned off, but the gas flow rate is kept constant. After the furnace temperature drops to room temperature, the gas source is turned off, the tail valve is opened, and the titanium sheet with the nano-modified TiOx layer with high distortion surface is taken out. Its appearance color is close to gray.

[0063] Example 5

[0064] The specific implementation method is the same as in Example 1, the difference being that the ammonium salt used is different, resulting in different decomposition temperatures for producing H2 and N2, which affects the absorbance of the product in the visible spectrum. After ultrasonic cleaning with acetone and drying, a titanium sheet with a white TiO2 modified layer is obtained. After uniformly coating the surface of the prepared white TiO2 modified titanium sheet with 0.3 mm thick NH4Cl white powder, it is placed horizontally in the heating zone of the PECVD furnace near the PE source, with its surface parallel to the gas flow direction, and then the furnace body is sealed. Argon gas is continuously introduced into the sealed furnace chamber at a flow rate of 1 L / min for 10 min to remove impurity gases from the furnace chamber. After the exhaust is completed, argon gas is continuously introduced at a rate of 0.1 L / min, and the furnace body is slowly heated to 150°C at a heating rate of 6°C / min so that NH4Cl can be slowly decomposed into H2, N2 and H2O. After NH4Cl begins to decompose slowly, the radio frequency power supply is turned on and the power is adjusted to 450W to ionize H2 and N2 plasma. After the glow discharge stabilizes, the furnace is held at this temperature for another 3 hours. Throughout the process, the furnace pressure is controlled by the tail valve to remain below 200Pa. After the holding period, the radio frequency power supply is turned off, but the gas flow rate is kept constant. After the furnace temperature drops to room temperature, the gas source is turned off, the tail valve is opened, and the titanium sheet with the nano-modified TiOx layer on the highly distorted surface is removed. Its appearance color is close to gray-black.

[0065] Example 6

[0066] The specific implementation method is the same as in Example 1, except that the oxidation method used is anodic oxidation. The prepared nanocrystalline titanium sheet is used as the anode plate, and a stainless steel plate as the cathode plate, both immersed in a 15 g / L Na3PO4 electrolyte and arranged in parallel face-to-face with a distance of 50 mm between them. At 100 V, the current density is increased to 3 A / dm³ at a rate of 0.5 A / min. 3 The sample was oxidized for 15 minutes while maintaining a constant current density, after which the power was turned off and the sample was removed. After ultrasonic cleaning with acetone and drying, a titanium sheet with a grayish-white TiO2 modified layer on the surface was obtained.

[0067] Test Example 1

[0068] 1. Take two 150ml quartz cups, clean them with ultrasonication, and fill each cup with 100ml of Rhodamine-B solution (concentration: 10mg / l). Use a UV-Vis spectrophotometer to measure the absorbance C0 of the solution at this time.

[0069] 2. Take raw titanium alloy sheet, ordinary white TiO2 modified titanium sheet, and high distortion surface nano-modified TiOx modified titanium sheet, and add them into three quartz cups respectively, and label the cups as A, B, and C;

[0070] 3. Place the three quartz beakers under a 30W xenon lamp and start timing. Every hour, take 20 ml of Rhodamine-B solution and measure its absorbance using a UV-Vis spectrophotometer. Record the absorbance as C. A1 C A2 ...C A5 C B1 C B2 ...C B5 C C1 C C2 ...C C5 After each test, the sample solution was poured back into the original quartz cup to continue photocatalytic degradation treatment.

[0071] 4. Test the absorbance C of Rhodamine-B solution after irradiation with a xenon lamp for different durations. t :C A1 C A2 ...C A5 C B1 C B2 ...C B5 C C1 C C2 ...C C5 The absorbance of the original solution is C0, and then according to the formula:

[0072]

[0073] The degradation rate of the solution after different xenon lamp irradiation times (ultraviolet light + visible light irradiation) can be calculated and plotted. Figure 8 ;

[0074] 5. By Figure 8 It is known that the raw titanium alloy titanium sheet has no ability to degrade organic dyes under xenon lamp irradiation, while the titanium sheet with nano-modified TiOx layer on a highly distorted surface has a strong photocatalytic ability to degrade organic dyes under xenon lamp irradiation, and its ability to degrade organic dyes is 2-3 times that of ordinary white titanium oxide modified layer with the same surface area.

[0075] Test Example 2

[0076] The test method is the same as in Test Example 1, except that the xenon lamp source uses a filter to block the ultraviolet light portion with wavelengths below 380nm, retaining only the visible light portion with wavelengths in the range of 380-800nm. The test results are as follows. Figure 9 As shown. By Figure 9 It can be seen that the raw titanium alloy sheet does not have the ability to degrade organic pollutants under visible light irradiation, while the titanium sheet with the highly distorted surface nano-modified TiOx layer has a certain photocatalytic degradation ability under visible light irradiation, whereas the ordinary white titanium oxide modified layer does not have the ability to photocatalytically degrade organic dyes. The UV-Vis diffuse reflectance diagram of the highly distorted surface nano-modified TiOx layer is shown below. Figure 7,from Figure 7 It can be seen that the nano-sized TiOx with high distortion surface has obvious absorption in the ultraviolet spectral region (wavelength <380 nm) and also has obvious absorption in the visible spectral region (380-800 nm), while the ordinary white TiO2 modified layer only has certain absorption in the ultraviolet spectral region and no absorption in the visible spectral region.

Claims

1. A method for preparing a nano-sized TiOx modified layer with high distortion surface, characterized in that, Includes the following steps: S1: Surface nanofiberization (1) Clean the surface of the titanium alloy substrate to obtain a clean substrate; (2) In an inert gas or vacuum environment, a clean substrate is ball-milled to form a nanocrystalline layer with a thickness of 1-30 μm on the surface of the substrate. S2: Electrochemical oxidation (1) The substrate forming the nanocrystalline layer is used as the anode plate and the stainless steel plate is used as the cathode plate. The anode plate and the cathode plate are arranged in parallel face to face and immersed in the electrolyte. The horizontal distance between the cathode plate and the anode plate is 40-60 mm. (2) Start the electrochemical oxidation power supply The electrochemical oxidation power source is either a micro-arc oxidation power source or an anodic oxidation power source. The method for electrochemical oxidation using the micro-arc oxidation power source is as follows: the voltage is controlled at 300-400V, and the current density is 8-12A / dm³. 2 The oxidation process is continued for 20-40 minutes. After the oxidation process is completed, the anode plate is removed, cleaned and dried. A layer of white TiO2 is formed on the surface of the nanocrystalline layer of the substrate. After testing, the white TiO2 is identified as rutile phase TiO2. A substrate with two modified layers is obtained. The method for electrochemical oxidation using the aforementioned anodic oxidation power supply is as follows: the voltage is controlled at 50-300V, and the current density is 0.5-5A / dm³. 3 The oxidation process is continued for 5-30 minutes. After the oxidation process is completed, the anode plate is removed, cleaned and dried. A layer of grayish-white TiO2 is formed on the surface of the nanocrystalline layer of the substrate. After testing, the grayish-white TiO2 is identified as rutile phase TiO2. A substrate with two modified layers is obtained. S3: Chemical reduction (1) The substrate with two modified layers is placed horizontally, and a layer of ammonium salt powder is evenly spread on the surface. The substrate is placed horizontally in the heating zone of the plasma CVD furnace near the plasma source, so that the surface of the substrate with two modified layers is parallel to the gas flow direction in the plasma CVD furnace and sealed. (2) Argon gas is continuously introduced into the sealed plasma CVD furnace to remove impurity gases in the sealed plasma CVD furnace. Argon gas is continuously introduced at a gas flow rate of 0.1-0.2 L / min, and the pressure of the sealed plasma CVD furnace is continuously controlled to be kept at <200 Pa. (3) Heat the ammonium salt powder to 160-350℃ at a heating rate of 5-10℃ / min to decompose it into H2, N2 and H2O; adjust the power of the radio frequency power supply to 300-600W to ionize the decomposed H2 and N2 plasma; after the glow is stable, keep it at the temperature for 0.5-8h. (4) After the heat preservation is completed, argon gas is continued to be introduced until the furnace temperature of the heating furnace drops to room temperature, and a matrix with a nano-modified TiOx layer with a highly distorted surface is obtained.

2. The method for preparing a nano-sized TiOx modified layer with high distortion surface according to claim 1, characterized in that, In step S1(1), ball milling is performed in a ball mill with an inverted figure-eight motion path, with a ball milling speed of 850-900 rpm and a ball milling time of 30-120 min.

3. The method for preparing a high-distortion surface nano-modified TiOx layer according to claim 1, characterized in that, The ball milling is a dry ball milling process, with a ball-to-material ratio of (6-7):1 by mass. The particle size of the ball milling media is φ6mm-φ8mm, and the ball milling media is one or more of the following: iron-based microspheres, iron-based regular geometric shapes, iron-based irregular geometric shapes, titanium-based microspheres, titanium-based regular geometric shapes, titanium-based irregular geometric shapes, cemented carbide microspheres, cemented carbide regular geometric shapes, and cemented carbide irregular geometric shapes.

4. The method for preparing a nano-sized TiOx modified layer with high distortion surface according to claim 1, characterized in that, In step S1(2), the inert gas is selected from Ar, He, Ne or N2.

5. The method for preparing a nano-sized TiOx modified layer with high distortion surface according to claim 1, characterized in that, In step S2(1), the electrolyte in the electrolyte solution is selected from one or more of phosphate, hydrogen phosphate, and silicate, and the concentration of the electrolyte in the electrolyte solution is 10-20 g / L.

6. The method for preparing a high-distortion surface nano-modified TiOx layer according to claim 1, characterized in that, In step S3(1), the thickness of the uniformly coated ammonium salt powder is 0.1-1 mm; the ammonium salt powder is selected from ammonium salt substances that decompose into N2 and H2 when heated.

7. A high-distortion surface nano-modified TiOx layer prepared according to claim 1, characterized in that, The structure of the highly distorted surface nano-sized TiOx modified layer is as follows: the innermost layer is closer to the substrate, the outermost layer is farther from the substrate, and an intermediate layer is provided between the innermost and outermost layers; wherein, the outermost layer of the highly distorted surface nano-sized TiOx modified layer is a highly distorted amorphous material; the intermediate layer of the highly distorted surface nano-sized TiOx modified layer is rutile phase TiO2; and the innermost layer of the highly distorted surface nano-sized TiOx modified layer is a self-nanosized titanium alloy.

8. The high-distortion surface nano-modified TiOx layer according to claim 7, characterized in that, The highly distorted surface nano-TiOx modified layer has a thickness of x<2; the substrate is a titanium alloy substrate.

9. The high-distortion surface nano-modified TiOx layer according to claim 7, characterized in that, The outermost layer has a thickness of 1-5 μm, the middle layer has a thickness of 1-25 μm, and the innermost layer has a thickness of 1-30 μm.

10. The high-distortion surface nano-modified TiOx layer according to claim 7, characterized in that, The outermost layer is a highly distorted amorphous material, which, depending on the degree of O reduction in TiOx, exhibits one of the following colors or a gradient: light gray, yellowish brown, dark blue, or black.

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