CN111763977A

CN111763977A - Preparation method of graphene-based super-hydrophobic aluminum alloy

Info

Publication number: CN111763977A
Application number: CN201910257836.2A
Authority: CN
Inventors: 陈宇
Original assignee: Binzhou University
Current assignee: Binzhou University
Priority date: 2019-04-01
Filing date: 2019-04-01
Publication date: 2020-10-13

Abstract

The invention belongs to the technical field of functional materials, and relates to a preparation method of a graphene-based super-hydrophobic aluminum alloy. The invention provides a preparation method of a graphene-based super-hydrophobic aluminum alloy, and particularly relates to a preparation method of a super-hydrophobic structure by adopting an electrodeposition method. Has the following advantages: on one hand, the aluminum alloy is etched in a linolenic acid medium to construct a rough structure on the surface of the aluminum alloy, on the other hand, the lamellar blocking function of graphene is fully exerted, the corrosion inhibition efficiency reaches more than 99 percent, and the corrosion inhibition method has wide industrial application prospect.

Description

Preparation method of graphene-based super-hydrophobic aluminum alloy

Technical Field

The invention belongs to the technical field of functional materials, and particularly relates to a preparation method of a graphene-based super-hydrophobic aluminum alloy.

Background

The aluminum alloy has the advantages of small specific gravity, high strength, good physical and chemical properties and cutting performance, stable size, low price, recyclability and the like, and has wide application prospect in the fields of automobiles, electronics, machinery, aviation, aerospace and the like. However, the aluminum alloy has negative electrode potential and active chemical property, and is very easy to corrode in humid atmosphere or neutral salt water solution, so that effective inhibition of corrosion of the aluminum alloy is very necessary for expanding the application of the aluminum alloy.

In recent years, inspired by the lotus effect, the super-hydrophobic surface with a contact angle of more than 150 degrees with a water drop has the strong hydrophobic characteristic that water molecules and corrosive ions are difficult to permeate into the super-hydrophobic surface, so that the corrosion resistance of the metal material is obviously improved.

At present, a super-hydrophobic structure is constructed on the surface of a metal material by the etching action of stearic acid on the metal material, but the super-hydrophobic structure has short service life and is easy to damage after being soaked in a corrosive medium for a long time. The preparation method of the super-hydrophobic surface reported at present either needs harsh equipment or has too long preparation time. Therefore, the preparation method of the simple, high-efficiency and long-life super-hydrophobic aluminum alloy has important economic significance and social significance.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides a method for preparing a quick and long-life super-hydrophobic aluminum alloy, and the super-hydrophobic structure constructed by the method is stable and is particularly suitable for protecting the aluminum alloy in a 3.5% NaCl solution corrosive medium.

The invention provides a preparation method of a graphene-based super-hydrophobic aluminum alloy, which comprises the following steps:

(1) aluminum alloy pretreatment:

the aluminum alloy is firstly respectively polished by 60-mesh, 120-mesh, 320-mesh, 600-mesh and 1200-mesh sand paper to remove impurities and oxides on the surface, then ultrasonically cleaned by absolute ethyl alcohol and acetone for 10 minutes to remove organic matters, and finally N is added₂Drying for later use;

(2) preparing a super-hydrophobic structure by electrodeposition:

the electrolyte formula consists of graphene oxide, linolenic acid and absolute ethyl alcohol, and the mass fractions of the graphene oxide, the linolenic acid and the absolute ethyl alcohol are respectively as follows: 20-40% of graphene oxide, 10-20% of linolenic acid and 40-70% of absolute ethyl alcohol, wherein the sum of the percentage contents of all the components is 100%. The preparation method of the super-hydrophobic aluminum alloy provided by the invention has the advantages that the constant potential is 2-5V, the electrodeposition time is 4-12 h, and the temperature is 30-50 ℃. On one hand, the invention utilizes linolenic acid to etch the aluminum alloy; on the other hand, the strong adsorption force of the graphene oxide on the surface of the aluminum alloy is utilized, so that a film layer with high blocking performance is formed, and a super-hydrophobic surface is constructed, so that the super-hydrophobic aluminum alloy has excellent corrosion resistance. The preparation process is simple, the reproducibility is good, expensive equipment is not needed, and the method has wide industrial application prospect.

The invention has the beneficial effects that:

1. the invention provides a preparation method of graphene-based super-hydrophobic aluminum alloy, which can obviously improve the corrosion resistance of the graphene-based super-hydrophobic aluminum alloy in a 3.5% NaCl solution corrosion medium;

2. the invention provides a preparation method of a graphene-based super-hydrophobic aluminum alloy, wherein linolenic acid and graphene oxide are adopted as electrolyte, and the obtained film layer has better super-hydrophobic performance;

3. the invention provides a preparation method of graphene-based super-hydrophobic aluminum alloy, which has lower applied voltage and can effectively reduce energy consumption;

4. the invention provides a preparation method of graphene-based super-hydrophobic aluminum alloy, which is short in electrodeposition time, and can construct a super-hydrophobic surface only in 6 hours at a voltage of 2V;

5. the invention provides a preparation method of graphene-based super-hydrophobic aluminum alloy, and the super-hydrophobic film has longer service life;

6. the invention provides a preparation method of a graphene-based super-hydrophobic aluminum alloy, which not only has a super-hydrophobic structure, but also has excellent corrosion resistance, and has excellent protection effect on the aluminum alloy in a 3.5% NaCl solution corrosion medium;

7. the invention provides a preparation method of graphene-based super-hydrophobic aluminum alloy, wherein the preparation method is simple, the energy consumption is low, and the electrolyte formula is non-toxic and pollution-free and can be applied to large-scale industrial application.

Drawings

FIG. 1: contact angle of untreated aluminum alloy;

FIG. 2: a contact angle of the graphene-based super-hydrophobic aluminum alloy;

FIG. 3: the electrochemical impedance test result of the untreated aluminum alloy in a 3.5% NaCl solution corrosion medium;

FIG. 4: and (3) electrochemical impedance results of the graphene-based super-hydrophobic aluminum alloy in a 3.5% NaCl solution corrosion medium.

Detailed Description

The invention is further described below with reference to the figures and examples. While the invention will be described in conjunction with the preferred embodiments, it will be understood that they are not intended to limit the invention to the embodiments. On the contrary, the invention is intended to cover alternatives, modifications and equivalents, which may be included within the scope of the invention as defined by the appended claims.

Example 1:

(1) aluminum alloy pretreatment:

the aluminum alloy is firstly respectively sieved by 60 meshes, 120 meshes, 320 meshes, 600 meshes andpolishing with 1200 mesh abrasive paper to remove impurities and oxides on the surface, ultrasonically cleaning with anhydrous ethanol and acetone for 10 min to remove organic substances, and treating with N₂Drying for later use;

(2) preparing a super-hydrophobic structure by electrodeposition:

the electrolyte formula consists of graphene oxide, linolenic acid and absolute ethyl alcohol, and the mass fractions of the graphene oxide, the linolenic acid and the absolute ethyl alcohol are respectively as follows: 20% of graphene oxide, 10% of linolenic acid and 70% of absolute ethyl alcohol. The preparation method of the super-hydrophobic aluminum alloy provided by the invention has the advantages that the constant potential is 5V, the electrodeposition time is 4 h, and the temperature is 30 ℃.

The contact angle of the prepared graphene-based super-hydrophobic aluminum alloy is measured by a contact angle tester, and compared with the aluminum alloy which is not subjected to super-hydrophobic treatment, the contact angle of the aluminum alloy is higher than 150 degrees after the aluminum alloy is treated by the method, as shown in figures 1 and 2.

Example 2:

(1) aluminum alloy pretreatment:

(2) preparing a super-hydrophobic structure by electrodeposition:

the electrolyte formula consists of graphene oxide, linolenic acid and absolute ethyl alcohol, and the mass fractions of the graphene oxide, the linolenic acid and the absolute ethyl alcohol are respectively as follows: 40% of graphene oxide, 20% of linolenic acid and 40% of absolute ethyl alcohol. The preparation method of the super-hydrophobic aluminum alloy provided by the invention has the advantages that the constant potential is 2V, the electrodeposition time is 12 h, and the temperature is 30 ℃.

The electrochemical impedance test is carried out on the graphene-based super-hydrophobic aluminum alloy in a 3.5% NaCl solution corrosion medium, and compared with the aluminum alloy which is not subjected to super-hydrophobic treatment, the results are shown in fig. 3, fig. 4 and table 2, after the graphene-based super-hydrophobic aluminum alloy is treated by the method, the charge transfer resistance is obviously increased, and the prepared graphene-based super-hydrophobic aluminum alloy has better corrosion resistance.

TABLE 2

Condition	R_ct, Ω.cm²	Corrosion inhibition efficiency%
			Without super-hydrophobic treatment	126
Super-hydrophobic	12086	99.0%

Claims

1. The preparation method of the graphene-based super-hydrophobic aluminum alloy is characterized by comprising the following two steps of:

(1) aluminum alloy pretreatment:

(2) preparing a super-hydrophobic structure by electrodeposition:

the electrolyte formula consists of graphene oxide, linolenic acid and absolute ethyl alcohol, and the mass fractions of the graphene oxide, the linolenic acid and the absolute ethyl alcohol are respectively as follows: 20-40% of graphene oxide, 10-20% of linolenic acid and 40-70% of absolute ethyl alcohol, wherein the sum of the percentage contents of all the components is 100%.

2. The preparation method of the graphene-based super-hydrophobic aluminum alloy provided by the invention has the advantages that the constant potential is 2-5V, the electrodeposition time is 4-12 h, and the temperature is 30-50 ℃, so that the graphene super-hydrophobic aluminum alloy can be obtained, and the super-hydrophobic aluminum alloy has excellent corrosion resistance in a 3.5% NaCl solution corrosion medium.

3. The method for preparing the graphene-based super-hydrophobic aluminum alloy according to claim 1, wherein the electrolyte formula consists of graphene oxide, linolenic acid and absolute ethyl alcohol.

4. The method for preparing the graphene-based super-hydrophobic aluminum alloy according to claim 1, wherein the aluminum alloy is firstly sanded by 60-mesh, 120-mesh, 320-mesh, 600-mesh and 1200-mesh sandpaper to remove impurities and oxides on the surface.

5. The method for preparing the graphene-based super-hydrophobic aluminum alloy according to claim 1, wherein the aluminum alloy after oil removal is subjected to N₂And drying for later use.

6. The method for preparing the graphene-based super-hydrophobic aluminum alloy according to claim 1, wherein the constant potential is 2-5V.

7. The preparation method of the graphene-based super-hydrophobic aluminum alloy according to claim 1, wherein the electrodeposition time is 4-12 h.

8. The method for preparing the graphene-based super-hydrophobic aluminum alloy according to claim 1, wherein the electrodeposition temperature is 30-50 ℃.