CN102888588B - Preparation method for super-amphiphobic metal surface - Google Patents

Abstract

The invention proposes a method for preparing a superamphiphobic metal surface, which belongs to the field of metal substrate surface treatment, including pretreatment of the metal substrate, attaching carbon particles to the metal substrate, depositing tetraethoxysilane on the metal substrate, and placing the metal substrate on the metal substrate. Annealing in a muffle furnace, followed by the step of depositing polyperfluoroalkylsiloxane, the resulting surface has superamphiphobic properties. The superamphiphobic surface is superphobic to aqueous solutions with a pH value of 0-14 and various oil droplets, and the contact angle to water is 171°C, and the rolling angle is less than 1°C. The contact angles of lubricating oil, edible oil, crude oil and other oil droplets are all greater than 150°, and the rolling angles are generally less than 10°. The superamphiphobic metal material prepared by the method has high stability, can maintain stable performance within several months, and can be widely used in scientific research, medicine, biology and other important fields.

Description

A kind of superamphiphobic metal surface and preparation method thereof

technical field

The invention belongs to the technical field of surface treatment of metal substrates, and in particular relates to a method for preparing superhydrophobic and superoleophobic metals, which produces an oily liquid on the surface of the metal that is compatible with water, aqueous solutions of different pH values, and edible oils, lubricating oils, and crude oils. The preparation method of the super-amphiphobic surface solves the existing technical problem of high cost for preparing the super-amphiphobic surface.

Background technique

The special wettability of the surface is an important characteristic of the solid surface. There are two main factors affecting the wettability of the solid surface: one is the surface chemical composition (surface free energy), and the other is the surface microstructure (roughness). With the in-depth study of special wetting surfaces in nature, the preparation methods of special wetting surfaces are emerging. In recent years, the preparation of superhydrophobic surfaces has received more and more attention, and many literatures have reported the preparation of surfaces with special wettability by different methods. In these literatures, the literature on superhydrophobicity accounts for the majority, and there are few reports on superoleophobic surfaces. A superamphiphobic surface refers to a surface with a contact angle of both water and oil greater than 150°. It has a very broad application prospect in industrial and agricultural production and people's daily life. For example, superamphiphobic surfaces are beneficial for self-cleaning in oily environments and removal of underwater biological pollution. Moreover, superamphiphobic metals are widely used in navigation, aerospace, pipeline transportation and many other fields. How to prepare superamphiphobic metal surfaces, especially superamphiphobic metal aluminum surfaces, has become a research hotspot.

Contents of the invention

The invention provides a method for preparing a superamphiphobic metal surface, which is used to realize the hydrophobic and oleophobic properties of the metal surface. The method has simple preparation process, strong superamphiphobic property, low preparation cost, convenient implementation, and can be popularized on a large scale. The superamphiphobic metal surface of the present invention has both superhydrophobic and superoleophobic properties in the air, and has a surface contact angle of >150° for edible oil, lubricating oil, crude oil, etc., and has low adhesion to oil droplets. The superamphiphobic metal of the present invention can be applied to navigation, aerospace, pipeline transportation and many other fields, and also has important uses in daily life.

The present invention proposes a method for preparing a superamphiphobic metal surface, which specifically includes the following steps:

The first step is metal substrate pretreatment.

In the second step, carbon particles are attached to one side of the sheet metal substrate treated in the first step.

In the third step, continue to deposit tetraethoxysilane on the side where the carbon particles are attached on the metal substrate.

The fourth step is to place the sheet metal substrate treated in the third step in a muffle furnace, burn it at 600~1000°C for 2~4 hours, and take it out for later use;

The fifth step is to place the sheet metal substrate treated in the fourth step in a vacuum desiccator at room temperature again, place polyperfluoroalkylsiloxane in the vacuum desiccator, and place it in vacuum for more than 12 hours to make the polyperfluoroalkylsiloxane Fluoroalkylsiloxanes are vapor deposited on the surface of metal substrates.

In the sixth step, the polyperfluoroalkylsiloxane placed in the fifth step is taken out, and the metal substrate is placed in a desiccator at room temperature for more than 24 hours, and then taken out to obtain a superamphiphobic metal surface.

The advantages of the present invention are:

1. A superamphiphobic metal surface proposed by the present invention has a simple preparation method, readily available raw materials, and low cost.

2. A superamphiphobic metal surface proposed by the present invention, the contact angle of the metal surface to water is greater than 170°, and has low adhesion.

3. A superamphiphobic metal surface proposed by the present invention, the contact angle of the metal surface to oil is greater than 150°, and has low adhesion.

4. A superamphiphobic metal surface proposed by the present invention, the metal substrate is pollution-free and recyclable.

5. The superamphiphobic metal surface proposed by the present invention can achieve the effect of anti-fouling and anti-corrosion, and has the function of self-cleaning at the same time.

Description of drawings

Fig. 1: the flow chart of preparing a kind of super amphiphobic metal substrate that the present invention proposes;

Fig. 2: Low magnification electron micrograph (SEM) of a metal substrate not processed by the method of the present invention;

Figure 3: A high-magnification electron micrograph (SEM) of a metal substrate not treated by the method of the present invention;

Figure 4: A low magnification electron microscope photo (SEM) of the surface of the metal substrate obtained after being treated by the method of the present invention;

Figure 5: A high-power electron microscope photo (SEM) of the surface of the metal substrate obtained after the method of the present invention;

Fig. 6: is the schematic diagram of the contact angle to water of the metal substrate not treated by the method of the present invention;

Fig. 7: is the schematic diagram of the contact angle to water of the metal substrate treated by the method of the present invention;

Fig. 8: is the schematic diagram of the contact angle of the metal substrate treated by the method of the present invention to oil;

Fig. 9: is the digital photograph of the contact angle of water, lubricating oil, edible oil, and crude oil for metal substrates treated by the method of the present invention;

Fig. 10 is a digital photo of the contact angle of the metal substrate treated by the method of the present invention to acid-base salts.

Detailed ways

The present invention will be further described in detail with reference to the accompanying drawings and embodiments.

The present invention proposes a method for preparing a superhydrophobic superoleophobic metal surface, as shown in Figure 1, the method comprises the following steps:

The first step, metal substrate pretreatment: take a beaker, pour deionized water into it, and immerse the sheet-shaped metal substrate in deionized water, (the described sheet-shaped metal substrate is preferably an aluminum substrate, a copper substrate, an iron substrate, etc., further Preferably aluminum substrate), put the beaker into an ultrasonic device and ultrasonically clean it for 5-20 minutes to clean the stains on the surface of the metal substrate; pour out the cleaning solution, and pour absolute ethanol (analytical alcohol, ethanol mass fraction ≥ 99.7%) into the beaker , continue to ultrasonically clean the metal substrate for 20~60min, remove the grease on the metal substrate, take it out and dry it (oven temperature 60~90℃), put it in 0.5~1mol/L sodium hydroxide or hydrochloric acid solution and corrode for 20~60min , take it out and dry it (oven temperature 60~90°C) for later use;

In the second step, place one side of the sheet metal substrate treated in the first step above the paraffin flame and burn for 5-10 seconds at each position, and a layer of 30-40nm black carbon particles will be attached. To attach, slowly move the metal substrate until the carbon particles cover the entire metal substrate.

In the third step, place the metal substrate treated in the second step in a vacuum desiccator at room temperature, and place 1~3mL (preferably 2mL) of tetraethoxy Silane and ammonia water, then evacuated for 15-30 minutes, and placed in vacuum for more than 24 hours to vapor-deposit tetraethoxysilane on the surface of the metal substrate, and take it out for later use.

The fourth step is to place the metal substrate treated in the third step in a muffle furnace, burn it at 600-1000°C (preferably 600°C) for 2-4h (preferably 2h), and take it out for later use;

In the fifth step, place the metal substrate treated in the fourth step in the vacuum desiccator again at room temperature, and place 0.05~0.3mL (preferably 0.1mL) of polyperfluoroalkylsiloxane in the vacuum desiccator (CF ₃ (CF ₂ ) ₇ CH ₂ CH ₂ Si(OCH ₃ ) ₃ ), vacuumize for 15~30min, and place in vacuum for more than 12h, usually 12~24h. The polyperfluoroalkylsiloxane is vapor-deposited on the surface of the metal substrate.

In the sixth step, take out the polyperfluoroalkylsiloxane placed in the vacuum desiccator in the fifth step, and continue to place the metal substrate in the vacuum desiccator for more than 24 hours at room temperature, and then take it out to obtain a superamphiphobic metal surface.

The superamphiphobic metal surface obtained by the above preparation method has a static contact angle of more than 170° for aqueous solutions with different pH values (PH is 0-14), a rolling angle of less than 1°C, and a static contact angle of edible oil greater than 150 °, the rolling angle is generally less than 10°, and has strong acid and alkali resistance.

Embodiment one

A kind of preparation method of the super amphiphobic metal surface that this embodiment proposes is the substrate with aluminum flake, and this method comprises the following steps:

(1) Surface pretreatment of aluminum sheet: Take a 50ml beaker and pour deionized water into it for later use. Immerse the aluminum sheet (10mm×20mm×0.5mm) in deionized water, put the beaker in an ultrasonic cleaning machine for cleaning for 5 minutes, and recover the cleaning solution. Pour absolute ethanol (analytical alcohol, ethanol mass fraction ≥ 99.7%) into the beaker, continue ultrasonic cleaning for 20 minutes, take out the aluminum sheet, dry it in a 60°C oven, and place it in 0.5mol/L sodium hydroxide Corrode in the solution for 40min, take it out and dry it in an oven at 60°C.

(2) Place one side of the aluminum sheet treated in step (1) above the paraffin flame and burn for 5 seconds at each position, and a layer of 30-40nm black carbon particles will adhere to it. Move the aluminum sheet until it covers the entire aluminum sheet.

(3) Place the aluminum sheet treated in step (2) in a vacuum desiccator at room temperature, place 1mL of tetraethoxysilane and ammonia water in the vacuum desiccator, then vacuumize for 15min, and place in vacuum for 24h. Vapor-deposit tetraethoxysilane on the surface of the aluminum sheet and take it out for later use.

(4) Put the aluminum sheet treated in step (3) in a muffle furnace, burn it at 600°C for 2 hours, and take it out for later use.

(5) Place the aluminum sheet treated in step (4) in a vacuum desiccator at room temperature again, place 0.05mL of polyperfluoroalkylsiloxane, and vacuumize for 15min to make polyperfluoroalkylsiloxane Oxane vapor deposition on the surface of the aluminum sheet, vacuum for 12h.

(6) After 12 hours, take out the polyperfluoroalkylsiloxane placed in the vacuum desiccator in step (5), and place the aluminum sheet in the vacuum desiccator at room temperature for 24 hours, and then take it out to obtain this The invented superamphiphobic aluminum sheet surface realizes the preparation of the superamphiphobic aluminum sheet surface.

Compared with the superhydrophobic and superoleophobic metal surface prepared above, compared with the metal substrate treated by the method of the present invention (as shown in Figure 2 and Figure 3), the treated metal substrate has obvious micro-nano structure (as shown in Figure 4 and Figure 5). The contact angle to water of the metal substrate not treated by the method of the present invention is 70° (as shown in Figure 6), while the contact angle of the metal substrate treated by the method of the present invention to water is 171° (as shown in Figure 7). The metal substrate treated by the inventive method has a contact angle to oil greater than 150° (as shown in Figure 8). As shown in Figure 9, it is a digital photo of the contact angle of the metal substrate processed by the method of the present invention to water, lubricating oil, edible oil, crude oil, as shown in Figure 10, it is the metal substrate processed by the method of the present invention. The digital photo of the contact angle of the acid-base salt shows that the super-amphiphobic metal obtained in the present invention has strong acid and alkali resistance.

Embodiment two

A kind of preparation method of the super amphiphobic metal surface that this embodiment proposes is the substrate with aluminum flake, and this method comprises the following steps:

(1) Surface pretreatment of aluminum sheet: Take a 50ml beaker and pour deionized water into it for later use. Immerse the aluminum sheet (20mm×20mm×1mm) in deionized water, put the beaker into the ultrasonic cleaning machine for cleaning for 10min, and recover the cleaning solution. Pour absolute ethanol (analytical alcohol, ethanol mass fraction ≥99.7%) into the beaker, continue ultrasonic cleaning for 40 minutes, take out the aluminum sheet, put it in a 70°C oven for drying, and place it in 0.75mol/L hydrochloric acid solution after taking it out Corrode for 60 minutes, take it out and dry it in an oven at 70°C.

(2) Put one side of the aluminum sheet treated in step (1) above the paraffin flame and burn for 6 seconds at each position, and a layer of 30-40nm black carbon particles will be attached. With the attachment of carbon particles, slowly Move the aluminum sheet until it covers the entire aluminum sheet.

(3) Place the aluminum sheet treated in step (2) in a vacuum desiccator at room temperature, place 2mL of tetraethoxysilane and ammonia water in the vacuum desiccator, then vacuumize for 20min, and place in vacuum for 36h. Vapor-deposit tetraethoxysilane on the surface of the aluminum sheet and take it out for later use.

(4) Put the aluminum sheet treated in step (3) in a muffle furnace, burn it at 800°C for 3 hours, and take it out for later use.

(5) Place the aluminum sheet treated in step (4) in a vacuum desiccator at room temperature again, place 0.1mL of polyperfluoroalkylsiloxane, and vacuumize for 20min to make polyperfluoroalkylsiloxane Oxane vapor deposition on the surface of the aluminum sheet, vacuum for 18h.

(6) After 18 hours, take out the polyperfluoroalkylsiloxane placed in step (5), and continue to place the aluminum sheet in the desiccator for 36 hours at room temperature, and then take it out to obtain the aluminum sheet super double The hydrophobic surface realizes the preparation of the super amphiphobic surface of aluminum flakes.

The surface of the superamphiphobic aluminum flake prepared above has static contact angle values greater than 170° to aqueous solutions with different pH values, and static contact angle values to edible oils greater than 150°, and has strong acid and alkali resistance.

Embodiment three

A kind of preparation method of the super amphiphobic metal surface that this embodiment proposes is the substrate with aluminum flake, and this method comprises the following steps:

(1) Surface pretreatment of aluminum sheet: Take a 50ml beaker and pour deionized water into it for later use. Immerse the aluminum sheet (20mm×30mm×1.5mm) in deionized water, put the beaker into the ultrasonic cleaning machine for cleaning for 20min, and recover the cleaning solution. Pour absolute ethanol (analytical alcohol, ethanol mass fraction ≥ 99.7%) into the beaker, continue ultrasonic cleaning for 60 minutes, take out the aluminum sheet, put it in a 90°C oven for drying, and place it in 1mol/L sodium hydroxide solution after taking it out Corrode in medium for 30 minutes, take it out and put it in a 90°C oven for drying.

(2) Put one side of the aluminum sheet treated in step (1) above the paraffin flame and burn for 8 seconds at each position, and a layer of 30-40nm black carbon particles will adhere to it. Move the aluminum sheet until it covers the entire aluminum sheet.

(3) Place the aluminum sheet treated in step (2) in a vacuum desiccator at room temperature, place 3mL of tetraethoxysilane and ammonia water in the vacuum desiccator, then vacuumize for 25min, and place in vacuum for 48h. Vapor-deposit tetraethoxysilane on the surface of the aluminum sheet and take it out for later use.

(4) Put the aluminum sheet processed in step (3) into a muffle furnace, burn it at 1000°C for 4 hours, and take it out for later use.

(5) Place the aluminum sheet treated in step (4) in a vacuum desiccator at room temperature again, place 0.3mL of polyperfluoroalkylsiloxane, and vacuumize for 25min to make polyperfluoroalkylsiloxane Oxane vapor deposition on the surface of the aluminum sheet, vacuum for 24h.

(6) After 24 hours, take out the polyperfluoroalkylsiloxane placed in step (5), continue to place the aluminum sheet in the desiccator at room temperature for 48 hours, and then take it out to obtain the aluminum sheet superamphiphobic On the surface, the preparation of the surface of super amphiphobic aluminum flakes has been realized.

The surface of the superamphiphobic aluminum flake prepared above has static contact angle values greater than 170° to aqueous solutions with different pH values, and static contact angle values to edible oils greater than 150°, and has strong acid and alkali resistance.

Embodiment Four

A kind of preparation method of the super amphiphobic metal surface that this embodiment proposes is the substrate with aluminum flake, and this method comprises the following steps:

(1) Surface pretreatment of aluminum sheet: Take a 50ml beaker and pour deionized water into it for later use. Immerse the aluminum sheet (10mm×20mm×0.5mm) in deionized water, put the beaker in an ultrasonic cleaning machine for cleaning for 5 minutes, and recover the cleaning solution. Pour absolute ethanol (analytical alcohol, ethanol mass fraction ≥ 99.7%) into the beaker, continue ultrasonic cleaning for 20 minutes, take out the aluminum sheet, put it in a 60°C oven for drying, and put it in a 1mol/L hydrochloric acid solution for corrosion 20min, take it out and dry it in a 60°C oven.

(2) Put one side of the aluminum sheet treated in step (1) above the paraffin flame and burn for 10 seconds at each position, and a layer of 30-40nm black carbon particles will be attached. With the attachment of carbon particles, slowly Move the aluminum sheet until it covers the entire aluminum sheet.

(3) Place the aluminum sheet treated in step (2) in a vacuum desiccator at room temperature, place 1mL of tetraethoxysilane and ammonia water in the vacuum desiccator, then vacuumize for 30min, and place in vacuum for 24h. Vapor-deposit tetraethoxysilane on the surface of the aluminum sheet and take it out for later use.

(4) Put the aluminum sheet treated in step (3) in a muffle furnace, burn it at 600°C for 2 hours, and take it out for later use.

(5) Place the aluminum sheet treated in step (4) in a vacuum desiccator again, place 0.1mL of polyperfluoroalkylsiloxane, and vacuumize for 30min to make polyperfluoroalkylsiloxane Vapor deposition on the surface of the aluminum sheet, vacuum for 12h.

(6) After 12 hours, take out the polyperfluoroalkylsiloxane placed in step (5), continue to place the aluminum sheet in the desiccator for 24 hours at room temperature, and then take it out to obtain the aluminum sheet super double The hydrophobic surface realizes the preparation of the super amphiphobic surface of aluminum flakes.

The surface of the superamphiphobic aluminum flake prepared above has static contact angle values greater than 170° to aqueous solutions with different pH values, and static contact angle values to edible oils greater than 150°, and has strong acid and alkali resistance.

Embodiment five

A kind of preparation method of the superamphiphobic metal surface that this embodiment proposes is the substrate with copper sheet, and this method comprises the following several steps:

(1) Surface pretreatment of copper sheet: Take a 50ml beaker and pour deionized water into it for later use. Immerse the copper sheet (10mm×20mm×0.5mm) in deionized water, put the beaker into the ultrasonic cleaning machine for cleaning for 5 minutes, and recover the cleaning solution. Pour absolute ethanol (analytical alcohol, ethanol mass fraction ≥99.7%) into the beaker, continue ultrasonic cleaning for 20 minutes, take out the copper sheet, put it in a 60°C oven for drying, and place it in 0.5mol/L hydrochloric acid solution after taking it out Corrode for 20 minutes, take it out and dry it in a 60°C oven.

(2) Put one side of the copper sheet treated in step (1) above the paraffin flame and burn for 8 seconds at each position, and a layer of 30-40nm black carbon particles will be attached. With the attachment of carbon particles, slowly Move the copper sheet until it covers the entire copper sheet.

(3) Place the copper sheet treated in step (2) in a vacuum desiccator at room temperature, place 1mL of tetraethoxysilane and ammonia water in the vacuum desiccator, then vacuumize for 20min, and place in vacuum for 24h. Vapor-deposit tetraethoxysilane on the surface of the copper sheet and take it out for later use.

(4) Put the copper sheet treated in step (3) in a muffle furnace, burn it at 600°C for 2 hours, and take it out for later use.

(5) Place the copper sheet treated in step (4) in a vacuum desiccator at room temperature again, place 0.05mL of polyperfluoroalkylsiloxane, and vacuumize for 20min to make polyperfluoroalkylsiloxane Oxygen was vapor-phase deposited on the surface of the copper sheet, and placed in vacuum for 12 hours.

(6) After 12 hours, take out the polyperfluoroalkylsiloxane placed in step (5), and place the copper sheet in the desiccator for 24 hours at room temperature, and then take it out to obtain the super double copper sheet of the present invention. The hydrophobic surface realizes the preparation of super amphiphobic surface of copper sheet.

Embodiment six

A kind of preparation method of the superamphiphobic metal surface that this embodiment proposes is the base with iron plate, and this method comprises the following several steps:

(1) Surface pretreatment of iron sheets: Take a 50ml beaker and pour it into deionized water for later use. Immerse the iron piece (10mm×20mm×0.5mm) in deionized water, put the beaker in an ultrasonic cleaning machine for 10 minutes, and recover the cleaning solution. Pour anhydrous ethanol (analytical alcohol, ethanol mass fraction ≥ 99.7%) into the beaker, continue ultrasonic cleaning for 20 minutes, take out the iron sheet, put it in a 70°C oven for drying, take it out and put it in a 1mol/L hydrochloric acid solution for corrosion After 40 minutes, take it out and dry it in a 70°C oven.

(2) Put one side of the iron sheet treated in step (1) above the paraffin flame and burn for 8 seconds at each position, and a layer of 30-40nm black carbon particles will be attached. With the attachment of carbon particles, slowly Move the iron sheet until it covers the entire iron sheet.

(3) Place the iron sheet treated in step (2) in a vacuum desiccator at room temperature, place 1mL of tetraethoxysilane and ammonia water in the vacuum desiccator, then vacuumize for 20min, and place in vacuum for 24h. Vapor-deposit tetraethoxysilane on the surface of the iron sheet and take it out for later use.

(4) Put the iron sheet treated in step (3) in a muffle furnace, burn it at 600°C for 2 hours, and take it out for later use.

(5) Place the iron sheet treated in step (4) in a vacuum desiccator at room temperature again, place 0.05mL of polyperfluoroalkylsiloxane, and vacuumize for 20min to make polyperfluoroalkylsiloxane Oxygen is vapor-phase deposited on the surface of the iron sheet, and placed in vacuum for 12 hours.

(6) After 12 hours, take out the polyperfluoroalkylsiloxane placed in step (5), and place the iron sheet in the desiccator for 24 hours at room temperature, and then take it out to obtain the iron sheet super double The hydrophobic surface realizes the preparation of the iron sheet superamphiphobic surface.

Claims (5)

1. a preparation method for super two thin metallic surfaces, is characterized in that: described preparation method comprises following step:

The first step, metal base pre-treatment;

Second step, adheres to carbon granule by the sheet metal substrate one side of handling well in the first step; Be specially:

Sheet metal substrate one side is placed in the top calcination of paraffin flame, and 5～10s is burnt in each position, can adhere to the carbon granule of one deck 30～40nm black, and along with adhering to of carbon granule, slowly moving metal substrate, until carbon granule is covered with whole metal base;

The 3rd step, a side of adhering to carbon granule in metal base continues deposition tetraethoxysilane; Be specially:

Metal base is placed in more than vacuum drier places 24h, makes tetraethoxysilane vapour deposition in metal substrate surface, takes out for subsequent use; In described vacuum drier, be placed with respectively tetraethoxysilane and ammoniacal liquor that volume ratio is 1:1;

The 4th step, by the sheet metal substrate of handling well in the 3rd step, is placed in retort furnace, burns 2～4h at 600～1000 DEG C, takes out for subsequent use;

The 5th step, by the sheet metal substrate of processing through the 4th step, be again placed in vacuum drier under room temperature, in vacuum drier, place poly-perfluoroalkyl siloxanes, more than vacuum is placed 12h, make poly-perfluoroalkyl siloxanes vapour deposition in metal substrate surface; Poly-perfluoroalkyl siloxanes 0.05～0.3mL in vacuum drier;

The 6th step, takes out the poly-perfluoroalkyl siloxanes of placing in the 5th step, and at room temperature, metal base continues to be placed in moisture eliminator more than 24h, takes out afterwards, obtains super two thin metallic surface.

2. the preparation method of a kind of super two thin metallic surfaces according to claim 1, is characterized in that: described metal base pre-treatment is specially: first use deionized water ultrasonic cleaning; Then use dehydrated alcohol ultrasonic cleaning; Again clean with sodium hydroxide or hydrochloric acid soln corrosion.

3. the preparation method of a kind of super two thin metallic surfaces according to claim 2, it is characterized in that: described corrosion is cleaned and is specially: sodium hydroxide or hydrochloric acid soln that metal base is put into 0.5～1mol/L corrode 20～60min, take out stand-by after 60～90 DEG C of oven dry of temperature.

4. super two thin metallic surfaces, it is characterized in that: adopt preparation method claimed in claim 1, described super two thin metallic surfaces are all greater than 170 ° to the static contact angle numerical value of the different PH aqueous solution, and the static contact angle numerical value of edible oil is all greater than to 150 °.

5. the super two thin metallic surfaces of one according to claim 4, is characterized in that: described super two thin metallic surfaces are micro-nano structure.