CN101191248B - Method for preparing titanium dioxide nano tube array on titanium-substrate material surface - Google Patents

Abstract

The invention discloses a method for preparing a titanium dioxide nanotube array layer on the surface of a titanium base material. The titanium base material is subjected to electrochemical anodic oxidation treatment in an electrolyte solution containing HF acid after surface pretreatment, and the mixed electrolyte solution is composed of phosphoric acid Ammonium dihydrogen is 1-3mol/L, hydrofluoric acid is 0.2-0.4mol/L, and the surface structure of amorphous titanium dioxide nanotubes is obtained; the subsequent heat treatment conditions are in an air atmosphere, the heating rate is 3°C/min, and the temperature is kept at 450°C for 3 hours, and then cooled to room temperature with the furnace to obtain anatase titanium dioxide nanotube array layer. The electrolyte system of the method of the invention can control the oxidation and corrosion to reach a balance within a relatively long time range, thereby better controlling the morphology of the titanium dioxide nanotubes. The method of the invention is easy to operate and low in cost, and the prepared titanium dioxide nanotube arrays are oriented and regularly arranged, and the amorphous titanium dioxide nanotubes are produced in a direction perpendicular to the substrate, with a tube diameter of 80-100 nm, a wall thickness of 18-21 nm, and a tube length of 0.7 ~2.0μm, large specific surface area.

Description

Method for preparing titanium dioxide nanotube array layer on the surface of titanium base material

technical field

The invention belongs to the field of nanometer materials, in particular to a method for preparing a titanium dioxide nanotube array layer on the surface of pure titanium or titanium alloy.

Background technique

Titanium and titanium alloys are light in weight, high in strength and good in corrosion resistance, and have been widely used in aerospace, machinery manufacturing, biomedical materials and other fields. However, when it is used, it is often necessary to modify its surface. The purpose is to obtain a surface with better performance, such as laser melting TiN and TiC to improve its hardness and wear resistance; to improve the titanium surface by depositing a coating. Excellent corrosion resistance, high temperature resistance and wear resistance; the microstructure of titanium surface can be changed by surface nanometerization, and the mechanical properties can be improved.

Titanium dioxide is an important inorganic functional material. Nano-titanium dioxide has small crystal size and unique nano-size effect, humidity sensitivity, gas sensitivity, dielectric effect, photoelectric conversion, photochromic and superior photocatalysis, good biocompatibility and corrosion resistance. It is widely used in the fields of sensors, dielectric materials, photocatalysis, solar cells, self-cleaning materials and biological materials. Therefore, preparing a layer of nano-titanium dioxide on the surface of titanium and titanium alloys can better improve their functional properties.

Titanium dioxide nanotubes are a form of nanoscale titanium dioxide. The methods for preparing nanotube arrays on the surface of titanium and titanium alloys include template method and anodic oxidation method. In the template method, a porous and ordered alumina template or a polymer template must first be prepared, and then titania nanotubes are prepared by a sol-gel method or an electrochemical deposition method. The main disadvantage of this method is that the process is complicated and the preparation The morphology of titania nanotubes is dependent on the template. The anodic oxidation method is relatively simple and can directly form nanotube arrays on the titanium surface. However, the currently reported methods usually have the disadvantages of high electrolyte cost and inconvenient process operation. Chinese patent application 200510125502.8 uses simple HF acid as the electrolyte, which has a single system, rapid pH drop, short time for oxidation and corrosion to reach equilibrium, and it is difficult to increase the length of nanotubes and control the shape of nanotubes.

Contents of the invention

The basic idea of the present invention is to use titanium or titanium alloy as the anode, titanium, platinum or graphite as the cathode, select in an appropriate electrolyte, apply a voltage, titanium can form a titanium dioxide film on the surface through oxidation, and obtain nano The morphology of the tube is then crystallized by heat treatment to crystallize the surface nano-TiO2. Specifically, it can be described as:

A method for preparing a titanium dioxide nanotube array layer on the surface of a titanium base material, the titanium base material is subjected to electrochemical anodic oxidation treatment in an electrolyte solution containing HF acid after surface pretreatment, and the titanium base material after the electrochemical anodic oxidation treatment After heat treatment, the anatase titanium dioxide nanotube array is obtained, and the following steps are used to obtain the titanium dioxide nanotube array layer:

1) After the titanium substrate is polished step by step, it is cleaned in acetone and distilled water in sequence; the cleaned titanium substrate is acid-etched in a mixed solution containing 6.0mol/L nitric acid and 1-3mol/L hydrofluoric acid to no Bubbles are generated, then rinse the surface of the substrate with distilled water, dry it quickly and then dry it in air at room temperature to obtain the etched titanium substrate;

2) Put the etched titanium substrate obtained from 1) into a mixed electrolyte solution with the following components: ammonium dihydrogen phosphate 1-3 mol/L, hydrofluoric acid 0.2-0.4 mol/L; carry out constant-voltage anodic oxidation, The specific electrolysis parameters are: voltage 20V, electrode spacing 2-5cm, electrolytic cell temperature kept at room temperature; 3), heat treatment of the product with the surface structure of amorphous titanium dioxide nanotubes obtained in 2): under air atmosphere, the heating rate 3°C/min, 450°C for 3 hours, and then cooled to room temperature with the furnace; finally, an anatase titanium dioxide nanotube array layer was prepared on the surface of the pure titanium substrate.

The electrolyte system of the method of the invention can control the oxidation and corrosion to reach a balance within a relatively long time range, thereby better controlling the morphology of the titanium dioxide nanotubes. The method of the invention is easy to operate and low in cost, and the prepared titanium dioxide nanotube arrays are oriented and regularly arranged, and the amorphous titanium dioxide nanotubes are produced in a direction perpendicular to the substrate, with a tube diameter of 80-100 nm, a wall thickness of 18-21 nm, and a tube length of 0.7 ~2.0μm, large specific surface area.

Detailed ways

A method for preparing a titanium dioxide nanotube array coating on the surface of pure titanium or titanium alloy according to the present invention, the steps are as follows: 1) cutting pure titanium (general impurity component content is not more than 0.5%) or titanium alloy into pieces, followed by 280#, 400#, and 1000# water-resistant silicon carbide sandpaper, and then ultrasonically cleaned in acetone and distilled water; 2) acid-etched in a mixed solution containing 6.0mol/L nitric acid and a small amount of hydrofluoric acid until no bubbles are generated, Then rinse the surface of the sample with distilled water, then quickly dry the etched sample with a hair dryer, and place it in the air for at least 1 hour before anodizing; 3) Prepare a mixed electrolyte, the specific components include: ammonium dihydrogen phosphate 1～ 3mol/L, hydrofluoric acid 0.2-0.4mol/L; appropriate amount of inorganic or organic additives can also be added; 4) electrolysis voltage 20V, electrode distance 2-5cm, electrolytic cell temperature kept at room temperature, anodic oxidation treatment, During the treatment process, the electrolyte should be kept stirring continuously; 5) heat treatment is carried out in air atmosphere, the heating rate is 3 ℃/min, from room temperature to 450 ℃ for a period of time, and then cooled to room temperature with the furnace.

The present invention will be further described below in conjunction with embodiment.

Example 1:

A thin titanium dioxide nanotube array layer was prepared on a pure titanium sheet with a diameter of 15 mm and a thickness of 1.5 mm.

(1) Polish a thin titanium sheet with a diameter of 15mm and a thickness of 1.5mm with 280#, 600#, and 1000# water-resistant silicon carbide sandpaper in sequence, and then ultrasonically clean it in acetone and distilled water for 10 minutes;

(2) Etch in a mixed solution containing 6.0 mol/L nitric acid and 1 mol/L hydrofluoric acid until no bubbles are generated, then rinse the surface of the sample with distilled water, then quickly dry the sample after etching, and place it in the air for at least 1 Carry out (4) operation after hours.

(3) Prepare 100 mL of mixed electrolyte solution, including ammonium dihydrogen phosphate with a concentration of 1 mol/L and hydrofluoric acid with a concentration of 0.4 mol/L.

(4) The voltage is 20V, the distance between the electrodes is 4cm, the temperature of the electrolytic cell is kept at room temperature, and the anodic oxidation treatment is performed for 60 minutes, and the electrolyte should be kept stirring continuously during the treatment.

(5) Carry out heat treatment in an air atmosphere with a heating rate of 3°C/min, from room temperature to 450°C for 3 hours, and then cool to room temperature with the furnace.

Test results: Titanium dioxide nanotubes are regularly grown on the surface of pure titanium, and the prepared titanium dioxide nanotube arrays are oriented and regularly arranged, and the amorphous titanium dioxide nanotubes are produced in the direction perpendicular to the substrate with a uniform diameter of about 100nm and a wall thickness of 20 ～21nm, tube length 800nm～1000nm.

Example 2:

A thick titanium dioxide nanotube array layer was prepared on a pure titanium sheet with a diameter of 15 mm and a thickness of 1.5 mm.

(1) Cut a pure titanium rod with a diameter of 15mm into 1.5mm thick slices, polish it with 280#, 600#, 1000# water-resistant silicon carbide sandpaper in turn, and then ultrasonically clean it in acetone and distilled water for 10 minutes.

(2) Etch in a mixed solution containing 6.0 mol/L nitric acid and 3 mol/L hydrofluoric acid until no bubbles are generated, then rinse the surface of the sample with distilled water, then quickly dry the sample after etching, and place it in the air for at least 1 Carry out (4) operation after hours.

(3) Prepare 100 mL of mixed electrolyte solution, including ammonium dihydrogen phosphate with a concentration of 1 mol/L and hydrofluoric acid with a concentration of 0.3 mol/L.

(4) The voltage is 20V, the distance between the electrodes is 4cm, the temperature of the electrolytic cell is kept at room temperature, and the anodic oxidation treatment is performed for 360 minutes, and the electrolyte should be kept stirring continuously during the treatment.

(5) Carry out heat treatment in an air atmosphere with a heating rate of 3°C/min, from room temperature to 450°C for 3 hours, and then cool to room temperature with the furnace.

Test results: Titanium dioxide nanotubes regularly grow on the surface of pure titanium, the tube diameter is about 100nm, the wall thickness is 20-21nm, and the tube length is 1.7-1.9μm.

Example 3:

A thin and small-diameter titanium dioxide nanotube array layer was prepared on a pure titanium sheet with a diameter of 15 mm and a thickness of 1.5 mm.

(1) (2) steps are the same as in Example 2.

(3) Prepare 100 mL of mixed electrolyte solution, including 10 mL of 30% hydrogen peroxide, 1 mol/L ammonium dihydrogen phosphate and 0.3 mol/L hydrofluoric acid.

(4) The voltage is 20V, the distance between the electrodes is 4cm, the temperature of the electrolytic cell is kept at room temperature, and the anodic oxidation treatment is performed for 60 minutes, and the electrolyte should be kept stirring continuously during the treatment.

(5) Carry out heat treatment in an air atmosphere with a heating rate of 3°C/min, from room temperature to 450°C for 3 hours, and then cool to room temperature with the furnace.

Test results: Titanium dioxide nanotubes regularly grow on the surface of pure titanium, the tube diameter is about 80nm, the tube wall is 18-19nm, the tube length is 0.7-0.8μm, and the surface is rougher than that of Examples 1 and 2.

Example 4:

A thick and small-diameter titanium dioxide nanotube array layer was prepared on a pure titanium sheet with a diameter of 15 mm and a thickness of 1.5 mm.

(1) (2) steps are the same as in Example 2.

(3) Prepare 100 mL of mixed electrolyte solution, including 70 mL of absolute ethanol, ammonium dihydrogen phosphate at a concentration of 1 mol/L and hydrofluoric acid at a concentration of 0.25 mol/L.

(4) The voltage is 20V, the distance between the electrodes is 4cm, the temperature of the electrolytic cell is kept at room temperature, and the anodic oxidation treatment is performed for 360 minutes, and the electrolyte should be kept stirring continuously during the treatment.

(5) Carry out heat treatment in an air atmosphere with a heating rate of 3°C/min, from room temperature to 450°C for 3 hours, and then cool to room temperature with the furnace.

Test results: Titanium dioxide nanotubes regularly grow on the surface of pure titanium, the tube diameter is about 80nm, the tube wall is 18-19nm, and the tube length is 1.8-1.9μm.

Example 5:

A thin titanium dioxide nanotube array layer was prepared on a pure titanium sheet with a diameter of 10 mm and a thickness of 1.5 mm.

(1) (2) steps are with embodiment 1.

(3) Prepare 100 mL of mixed electrolyte solution, including ammonium dihydrogen phosphate with a concentration of 1 mol/L and hydrofluoric acid with a concentration of 0.25 mol/L.

(4) The voltage is 20V, the distance between the electrodes is 4cm, the temperature of the electrolytic cell is kept at room temperature, and the anodic oxidation treatment is performed for 60 minutes, and the electrolyte should be kept stirring continuously during the treatment.

(5) Carry out heat treatment in an air atmosphere with a heating rate of 3°C/min, from room temperature to 450°C for 3 hours, and then cool to room temperature with the furnace.

Test results: Titanium dioxide nanotubes regularly grow on the surface of pure titanium, the tube diameter is about 100nm, and the tube length is 0.8-1.0μm.

Embodiment 6:

A thick titanium dioxide nanotube array layer was prepared on a pure titanium sheet with a diameter of 10 mm and a thickness of 1.5 mm.

(1) (2) steps are the same as in Example 2.

(3) Prepare 100 mL of mixed electrolyte solution, including ammonium dihydrogen phosphate with a concentration of 1 mol/L and hydrofluoric acid with a concentration of 0.2 mol/L.

(4) The voltage is 20V, the distance between the electrodes is 4cm, the temperature of the electrolytic cell is kept at room temperature, and the anodic oxidation treatment is performed for 360 minutes, and the electrolyte should be kept stirring continuously during the treatment.

(5) Carry out heat treatment in an air atmosphere with a heating rate of 3°C/min, from room temperature to 450°C for 3 hours, and then cool to room temperature with the furnace.

Test results: Titanium dioxide nanotubes regularly grow on the surface of pure titanium, the tube diameter is about 100nm, and the tube length is 1.8-2.0μm.

Embodiment 7:

A thin titanium dioxide nanotube array layer was prepared on a titanium alloy sheet (Ti6Al4V) with a diameter of 15 mm and a thickness of 1.5 mm.

(1) (2) The steps are the same as those in Example 2, with titanium alloy rods replacing pure titanium rods.

(3) Prepare 100 mL of mixed electrolyte solution, including ammonium dihydrogen phosphate with a concentration of 1 mol/L and hydrofluoric acid with a concentration of 0.35 mol/L.

(4) The voltage is 20V, the distance between the electrodes is 4cm, the temperature of the electrolytic cell is kept at room temperature, and the anodic oxidation treatment is performed for 120 minutes, and the electrolyte should be kept stirring continuously during the treatment.

(5) Carry out heat treatment in an air atmosphere with a heating rate of 3°C/min, from room temperature to 450°C for 3 hours, and then cool to room temperature with the furnace.

Test results: Titanium dioxide nanotubes regularly grow on the surface of pure titanium, the tube diameter is about 100nm, and the tube length is 700nm-800nm.

Embodiment 8:

A thick titanium dioxide nanotube array layer was prepared on a titanium alloy sheet with a diameter of 15 mm and a thickness of 1.5 mm.

(1) (2) steps are the same as in Example 7.

(3) Prepare 100 mL of mixed electrolyte solution, including ammonium dihydrogen phosphate with a concentration of 1 mol/L and hydrofluoric acid with a concentration of 0.3 mol/L.

(4) The voltage is 20V, the distance between the electrodes is 4cm, the temperature of the electrolytic cell is kept at room temperature, and the anodic oxidation treatment is performed for 720 minutes, and the electrolyte should be kept stirring continuously during the treatment.

(5) Carry out heat treatment in an air atmosphere with a heating rate of 3°C/min, from room temperature to 450°C for 3 hours, and then cool to room temperature with the furnace.

Test results: Titanium dioxide nanotubes regularly grow on the surface of pure titanium, the tube diameter is about 100nm, and the tube length is 1.9-2.0μm.

Embodiment 9:

A thin titanium dioxide nanotube array layer was prepared on a titanium alloy sheet with a diameter of 8 mm and a thickness of 1.5 mm.

(1) (2) steps are the same as in Example 7.

(3) Prepare 100 mL of mixed electrolyte solution, including ammonium dihydrogen phosphate with a concentration of 3 mol/L and hydrofluoric acid with a concentration of 0.2 mol/L.

(4) The voltage is 20V, the distance between the electrodes is 4cm, the temperature of the electrolytic cell is kept at room temperature, and the anodic oxidation treatment is performed for 60 minutes, and the electrolyte should be kept stirring continuously during the treatment.

(5) Carry out heat treatment in an air atmosphere with a heating rate of 3°C/min, from room temperature to 450°C for 3 hours, and then cool to room temperature with the furnace.

Test results: Titanium dioxide nanotubes regularly grow on the surface of pure titanium, the diameter of which is about 90-100nm, and the tube length is 0.9-1.1μm.

The titanium dioxide nanotube array prepared by the method of the present invention has regular appearance and regular arrangement, and the amorphous titanium dioxide nanotubes have uniform diameters in the direction perpendicular to the substrate, and have special physical and chemical properties of nano titanium dioxide, which can be applied to catalytic chemistry , biomedical materials, optical materials and daily industry and other fields.

Claims (4)

1. A method for preparing a titanium dioxide nanotube array layer on the surface of a titanium base material, the titanium base material is subjected to electrochemical anodizing treatment in an electrolyte solution containing HF acid after surface pretreatment, and after the electrochemical anodizing treatment The titanium base material is subjected to heat treatment again to obtain anatase titanium dioxide nanotube array, it is characterized in that, adopt following steps to obtain titanium dioxide nanotube array layer: 1) After the titanium substrate is polished step by step, it is cleaned in acetone and distilled water in sequence; the cleaned titanium substrate is acid-etched in a mixed solution containing 6.0mol/L nitric acid and a small amount of hydrofluoric acid until no bubbles are generated, and then Rinse the surface of the substrate with distilled water, dry it quickly and then dry it in the air at room temperature to obtain the etched titanium substrate; 2) Put the etched titanium substrate obtained from 1) into a mixed electrolyte solution with the following components: ammonium dihydrogen phosphate 1-3 mol/L, hydrofluoric acid 0.2-0.4 mol/L; carry out constant-voltage anodic oxidation, The specific electrolysis parameters are: voltage 20V, electrode spacing 2-5cm, electrolytic cell temperature kept at room temperature; 3), heat treatment is carried out to the product with the surface structure of amorphous titania nanotubes obtained in 2): under the air atmosphere, the heating rate is 3 ℃/min, 450 ℃ for 3 hours, then cool to room temperature with the furnace; finally in pure An anatase titanium dioxide nanotube array layer is prepared on the surface of the titanium substrate. The titanium dioxide nanotubes are produced in a direction perpendicular to the substrate, with a diameter of 80-100 nm and a tube length of 0.7-2.0 μm. 2. The method for preparing a titanium dioxide nanotube array layer on the surface of a titanium base material according to claim 1, wherein the titanium base material is pure titanium or a titanium alloy. 3. The method for preparing a titanium dioxide nanotube array layer on the surface of a titanium base material according to claim 1, wherein absolute ethanol is added to the mixed electrolyte. 4. The method for preparing a titanium dioxide nanotube array layer on the surface of a titanium base material according to claim 1, wherein hydrogen peroxide is added to the mixed electrolyte.