CN110745911A

CN110745911A - Preparation method of titanium suboxide electrode

Info

Publication number: CN110745911A
Application number: CN201911062522.3A
Authority: CN
Inventors: 杨学兵; 郭炜; 陈威
Original assignee: Institute of Applied Physics of Jiangxi Academy of Sciences
Current assignee: Institute of Applied Physics of Jiangxi Academy of Sciences
Priority date: 2019-11-03
Filing date: 2019-11-03
Publication date: 2020-02-04

Abstract

A method for preparing a titanium suboxide electrode adopts a deposition method to prepare TiO on the surface of a titanium substrate₂A layer; then reducing the TiO₂Reduction of the layer to Ti₄O₇Layer of Ti to obtain Ti₄O₇And an electrode. The method comprises the steps of cleaning the surface of a titanium sheet, and TiO₂Preparation of the layer, Ti₄O₇Preparation of the layer. The preparation method has the advantages of simple process steps, high process controllability and high process stability, and controls the preparation process by adjusting process parameters. The electrochemical oxidation activity of the prepared titanium dioxide electrode is tested by degrading simulated organic wastewater, and the test result shows that the prepared titanium dioxide electrode has higher electrochemical oxidation activity.

Description

Preparation method of titanium suboxide electrode

Technical Field

The invention relates to a preparation method of a titanium suboxide electrode, belonging to the technical field of electrochemistry.

Background

The sewage containing organic matters is difficult to naturally degrade into harmless inorganic matters, the ecological environment can be seriously damaged when the wastewater polluted by harmful organic matters is discharged into the nature, the organic matters in the sewage need to be effectively degraded for protecting the ecological environment, and an efficient organic matter degradation method is a development trend of organic wastewater treatment. The electrochemical oxidation method is a method for degrading organic matters, the organic matters are oxidized and degraded on the surface of an anode, the efficiency of degrading the organic matters by the electrochemical oxidation method is related to that of an anode material, and the efficiency of degrading the organic matters by the anode material with higher electrochemical activity is higher.

Titanium (Ti) suboxide₄O₇Is an anode material of an electrochemical oxidation method, has higher conductivity and oxygen evolution potential, and enables Ti to be generated₄O₇The electrochemical oxidation activity of (2) is higher. Further, Ti₄O₇Has better corrosion resistance, which makes Ti₄O₇The electrode has a long service life, therefore, Ti₄O₇Is an ideal electrochemical oxidation anode material.

In the preparation of Ti₄O₇In the electrode process, TiO generally needs to be prepared first₂Pulverizing, and adding TiO₂Reduction of the powder to Ti₄O₇Powdering and then pulverizing Ti₄O₇Powdering to Ti₄O₇And (3) a layer. Ti₄O₇The preparation process of the electrode has more steps and low process stability. Simplified Ti₄O₇The electrode is prepared by Ti₄O₇The trend in electrode development.

Disclosure of Invention

The object of the present invention is to simplify Ti₄O₇The preparation process of the electrode improves the process stability, and provides a preparation method of the titanium suboxide electrode.

The technical scheme of the invention is that the method for preparing the titanium suboxide electrode adopts a microwave plasma deposition method to prepare TiO on the surface of a titanium substrate₂A layer; then reducing TiO by microwave plasma₂Reduction of the layer to Ti₄O₇Layer of Ti to obtain Ti₄O₇And an electrode.

A method for preparing a titanium suboxide electrode comprises the following steps:

(1) and cleaning the surface of the titanium sheet. Cutting a titanium sheet, grinding the surface of abrasive paper for 5min, putting the titanium sheet into absolute ethyl alcohol, ultrasonically cleaning for 30min, and then vacuum-drying the titanium sheet for 2h at 50 ℃;

（2）TiO₂preparation of the layer. Preparing TiO on the surface of a titanium substrate by adopting a deposition method₂Putting the titanium sheet into a reaction chamber, and vacuumizing to 10Pa by using a mechanical vacuum pump; introducing reaction gas, wherein the reaction gas comprises argon, oxygen and a titanium source, and the titanium source is carried into the reaction chamber by the argon; the microwave power is 300-400W, the argon flow is 400-600mL/min, the oxygen flow is 30-50mL/min, the titanium source vapor flow is 1-3mL/min, the air pressure is 20-30kPa, the deposition time is 3-4h, and TiO is prepared on the surface of the titanium substrate₂A layer;

（3）Ti₄O₇preparation of the layer. Reduction of TiO₂Reduction of the layer to Ti₄O₇The reaction chamber is unchanged, the reaction chamber is pumped to 10Pa by using a mechanical vacuum pump, and then reaction gas is introduced, wherein the reaction gas is hydrogen, the hydrogen flow is 130-150mL/min, and the air pressure is 14-16 kPa; the microwave power is 600-700W, the reaction time is 25-35min, and TiO is added₂Reduction of the layer to Ti₄O₇Layer of Ti to obtain Ti₄O₇And an electrode.

The reduction method is a microwave plasma reduction method.

The deposition method is a microwave plasma deposition method.

The titanium source is titanium tetrachloride.

The invention has the beneficial effects that the TiO in the invention₂Process for producing layer and Ti₄O₇The preparation process of the layer is carried out in the same reaction chamber, the process steps are not complex, the preparation process is controlled by adjusting the process parameters, and the process controllability and the process stability are higher.

Drawings

FIG. 1 is a schematic flow chart of a method for preparing a titanium suboxide electrode according to the present invention;

FIG. 2 shows Ti prepared in example 1₄O₇Graph of electrochemical oxidative degradation of phenol by electrodes.

Detailed Description

The specific embodiment of the present invention is shown in the flow chart of fig. 1.

Example 1

Cutting a titanium sheet, grinding the titanium sheet on sand paper for 5min, putting the titanium sheet into absolute ethyl alcohol, ultrasonically cleaning the titanium sheet for 30min, and then drying the titanium sheet for 2h in vacuum at 50 ℃.

Preparing TiO on the surface of a titanium substrate by adopting a microwave plasma deposition method₂And (3) a layer. Firstly, putting a titanium sheet into a reaction chamber, then vacuumizing to 10Pa by using a mechanical vacuum pump, and then introducing reaction gases, wherein the reaction gases comprise argon, oxygen and titanium tetrachloride vapor; the titanium tetrachloride vapor is carried into the reaction chamber by argon, the flow of the argon is 400mL/min, the flow of the oxygen is 30mL/min, the flow of the titanium tetrachloride vapor is 1mL/min, the air pressure is adjusted to be 20kPa, the microwave power is 300W, and the deposition time is 4 h.

To produce TiO₂After the layer, TiO is reduced by microwave plasma₂Reduction of the layer to Ti₄O₇Keeping the reaction chamber unchanged, vacuumizing to 10Pa by using a mechanical pump, introducing reaction gas, adjusting the pressure of the reaction gas to 14kPa, the microwave power to 600W, and the reduction time to 35min, and reacting TiO with hydrogen gas, wherein the hydrogen gas flow is 130mL/min, the microwave power to 600W, and the reduction time to 35min₂Reduction of the layer to Ti₄O₇Layer of Ti to obtain Ti₄O₇And an electrode.

Preparing phenol solution, using the phenol solution as simulated wastewater for testing Ti₄O₇Electrochemical oxidative degradation activity of the electrode.

The concentration of phenol in the phenol solution was 100mg/L, and the concentration of sodium sulfate was 14.2 g/L. The chemical oxygen demand of the phenol solution was measured every 30min, with the high and low chemical oxygen demand corresponding to the high and low phenol concentration. When the current density is 1.2mA/cm²In the time, the curve of the change of the chemical oxygen demand with time is shown in figure 2, the initial chemical oxygen demand is 215mg/L, the chemical oxygen demand after 180min is 42mg/L, and the removal rate of phenol is 80.5%, which indicates that the electrochemical oxidation activity of the prepared titanium suboxide electrode is higher.

Example 2

Preparing TiO on the surface of a titanium substrate by adopting a microwave plasma deposition method₂And (3) a layer. Firstly, putting a titanium sheet into a reaction chamber, then utilizing a mechanical vacuum pump to pump vacuum to 10Pa,and introducing reaction gases, wherein the reaction gases comprise argon, oxygen and titanium tetrachloride vapor, the titanium tetrachloride vapor is carried into the reaction chamber by the argon, the flow of the argon is 500mL/min, the flow of the oxygen is 40mL/min, the flow of the titanium tetrachloride vapor is 2mL/min, the air pressure is adjusted to be 25kPa, the microwave power is 350W, and the deposition time is 3.5 h.

To produce TiO₂After the layer, TiO is reduced by microwave plasma₂Reduction of the layer to Ti₄O₇Keeping the reaction chamber unchanged, vacuumizing to 10Pa by using a mechanical pump, introducing reaction gas, adjusting the pressure of the reaction gas to 15kPa, the microwave power to 650W, and the reduction time to 30min, wherein the reaction gas is hydrogen, the hydrogen flow is 140mL/min, and the TiO is subjected to reaction₂Reduction of the layer to Ti₄O₇Layer of Ti to obtain Ti₄O₇And an electrode.

The concentration of phenol in the phenol solution was 100mg/L, and the concentration of sodium sulfate was 14.2 g/L. The chemical oxygen demand of the phenol solution was measured every 30min, with the high and low chemical oxygen demand corresponding to the high and low phenol concentration. When the current density is 1.2mA/cm²In the process, the initial chemical oxygen consumption is 215mg/L, the chemical oxygen demand after 180min is 38mg/L, and the removal rate of phenol is 82.3%, which shows that the electrochemical oxidation activity of the prepared titanium suboxide electrode is higher.

Example 3

Cutting a titanium sheet, grinding the titanium sheet on sand paper for 5min, putting the titanium sheet into absolute ethyl alcohol, ultrasonically cleaning the titanium sheet for 30min, and then drying the titanium sheet for 2h in vacuum at 50 ℃. Preparing TiO on the surface of a titanium substrate by adopting a microwave plasma deposition method₂And (3) a layer. Firstly, putting a titanium sheet into a reaction chamber, then, vacuumizing to 10Pa by using a mechanical vacuum pump, and then, introducing reaction gas, wherein the reaction gas comprises argon, oxygen and titanium tetrachloride vapor, the titanium tetrachloride vapor is carried into the reaction chamber by the argon, the flow of the argon is 600mL/min, the flow of the oxygen is 50mL/min, the flow of the titanium tetrachloride vapor is 3mL/min, the air pressure is adjusted to be 30kPa, the microwave power is 400W, and the deposition time is 3 h.

To produce TiO₂After the layer, TiO is reduced by microwave plasma₂Reduction of the layer to Ti₄O₇Keeping the reaction chamber unchanged, vacuumizing to 10Pa by using a mechanical pump, introducing reaction gas, adjusting the pressure of the reaction gas to 16kPa, the microwave power to 700W, and the reduction time to 25min, and reacting TiO with hydrogen gas, wherein the hydrogen gas flow is 150mL/min, the microwave power is 700W, and₂reduction of the layer to Ti₄O₇Layer of Ti to obtain Ti₄O₇And an electrode.

The concentration of phenol in the phenol solution was 100mg/L, and the concentration of sodium sulfate was 14.2 g/L. The chemical oxygen demand of the phenol solution was measured every 30min, with the high and low chemical oxygen demand corresponding to the high and low phenol concentration. When the current density is 1.2mA/cm²When the electrochemical oxidation activity of the prepared titanium dioxide electrode is high, the initial chemical oxygen consumption is 215mg/L, the chemical oxygen demand after 180min is 44mg/L, and the removal rate of phenol is 79.5%.

Claims

1. The preparation method of the titanium suboxide electrode is characterized in that the method adopts a microwave plasma deposition method to prepare TiO on the surface of a titanium substrate₂A layer; then reducing TiO by microwave plasma₂Reduction of the layer to Ti₄O₇Layer of Ti to obtain Ti₄O₇And an electrode.

2. The method of claim 1, wherein the method comprises the steps of:

(1) cleaning the surface of a titanium sheet, cutting the titanium sheet, grinding the cut titanium sheet on the surface of abrasive paper for 5min, putting the titanium sheet into absolute ethyl alcohol, ultrasonically cleaning for 30min, and then drying the titanium sheet at 50 ℃ for 2h in vacuum;

（2）TiO₂preparing a layer, namely preparing TiO on the surface of a titanium substrate by adopting a deposition method₂Putting a titanium sheet into a reaction chamber, and vacuumizing to 10Pa by using a vacuum pump; introducing a reaction gas including argonOxygen and a titanium source; reacting for 3-4h under the conditions of proper microwave power, argon flow, oxygen flow, titanium source vapor flow and air pressure to prepare TiO on the surface of the titanium substrate₂A layer;

（3）Ti₄O₇preparation of the layer by reduction of TiO₂Reduction of the layer to Ti₄O₇The reaction chamber is unchanged, the reaction chamber is pumped to 10Pa by using a mechanical vacuum pump, then reaction gas is introduced, the reaction gas is hydrogen, and the reaction is carried out for 25-35min under the conditions of proper microwave power, hydrogen flow and air pressure; adding TiO into the mixture₂Reduction of the layer to Ti₄O₇Layer of Ti to obtain Ti₄O₇And an electrode.

3. The method for producing a titanium suboxide electrode according to claim 2, wherein the titanium source in the step (2) is titanium tetrachloride; the titanium source was carried into the reaction chamber by argon gas.

4. The method as claimed in claim 2, wherein the microwave power in step (2) is 300-400W.

5. The method as claimed in claim 2, wherein the microwave power in step (3) is 600-700W.

6. The method for preparing a titanium dioxide electrode according to claim 2, wherein the deposition method in the step (2) is a microwave plasma deposition method.

7. The method for preparing a titanium monoxide electrode as claimed in claim 2, wherein the reduction method in the step (3) is a microwave plasma reduction method.

8. The method as claimed in claim 2, wherein the flow rate of argon gas in step (2) is 400-600mL/min, the flow rate of oxygen gas is 30-50mL/min, the flow rate of titanium source vapor is 1-3mL/min, and the pressure is 20-30 kPa.

9. The method as claimed in claim 2, wherein the flow rate of hydrogen in step (3) is 150mL/min, and the pressure is 14-16 kPa.