阅读说明：本技术 一种基于逆置换在铜表面制备钴硫薄膜的方法 (Method for preparing cobalt-sulfur film on copper surface based on reverse replacement ) 是由 张兴凯 张俊彦 甘楠 于 2019-07-11 设计创作，主要内容包括：本发明涉及铜表面制备钴硫薄膜的方法,具体为一种基于逆置换在铜表面制备钴硫薄膜的方法,包括以下步骤：S1、制备逆置换沉积液：逆置换沉积液的组成及各组分的含量为：钴盐10-200g/L,添加剂90-320g/L,利用稀硫酸等将沉积液pH值调整为3-7；S2、铜试样处理：采用砂纸打磨铜基底,去除表面的氧化物和污染物,然后在乙醇溶液中超声清洗,氮气吹干；S3、沉积镀膜：铜试样放入逆置换沉积液中沉积；S4、钴硫薄膜铜试样处理：取出铜试样,用去离子水清洗残留的沉积液,用氮气吹干；采用本发明方法,能够直接在铜表面制备高质量钴硫薄膜,并且具有沉积液组成简单,操作流程少、耗时短和成本低等优势。(The invention relates to a method for preparing a cobalt-sulfur film on a copper surface, in particular to a method for preparing a cobalt-sulfur film on a copper surface based on reverse substitution, which comprises the following steps: s1, preparing a reverse displacement sediment liquid: the composition of the reverse displacement deposition solution and the content of each component are as follows: 10-200g/L of cobalt salt and 90-320g/L of additive, and adjusting the pH value of the deposition solution to 3-7 by using dilute sulfuric acid and the like; s2, copper sample treatment: polishing the copper substrate by using sand paper, removing oxides and pollutants on the surface, then ultrasonically cleaning in an ethanol solution, and drying by using nitrogen; s3, deposition coating: putting the copper sample into a reverse displacement deposition solution for deposition; s4, processing a cobalt-sulfur thin film copper sample: taking out the copper sample, washing the residual deposition solution with deionized water, and drying with nitrogen; the method can be used for directly preparing the high-quality cobalt-sulfur film on the copper surface, and has the advantages of simple composition of the deposition solution, less operation process, short time consumption, low cost and the like.)

1. A method for preparing a cobalt-sulfur film on a copper surface based on reverse substitution is characterized by comprising the following steps:

S1, preparing a reverse displacement sediment liquid: the composition of the reverse displacement deposition solution and the content of each component are as follows: 10-200g/L of cobalt salt and 90-320g/L of additive, and adjusting the pH value of the deposition solution to 3-7 by using dilute sulfuric acid and the like;

S2, copper sample treatment: polishing the copper substrate by using sand paper, removing oxides and pollutants on the surface, then ultrasonically cleaning in an ethanol solution, and drying by using nitrogen;

S3, deposition coating: putting the copper sample into a reverse displacement deposition solution for deposition;

S4, processing a cobalt-sulfur thin film copper sample: and taking out the copper sample, washing the residual deposition solution with deionized water, and drying with nitrogen.

2. The method for preparing the cobalt-sulfur film on the copper surface based on the reverse substitution as claimed in claim 1, wherein: in the step S1, the cobalt salt is one or more of cobalt sulfate, cobalt chloride, and cobalt nitrate.

3. The method for preparing the cobalt-sulfur film on the copper surface based on the reverse substitution as claimed in claim 1, wherein: in the step S1, the additive is one of thiosulfuric acid and thiourea.

4. The method for preparing the cobalt-sulfur film on the copper surface based on the reverse substitution as claimed in claim 1, wherein: in the step S2, 400#, 800#, 1200# sandpaper is used to polish the copper substrate.

5. the method for preparing the cobalt-sulfur film on the copper surface based on the reverse substitution as claimed in claim 1, wherein: in the step S3, the deposition coating conditions are as follows: the temperature of the reverse displacement deposition solution is 20-80 ℃, and the deposition time is 5-60 minutes.

Technical Field

The invention relates to a method for preparing a cobalt-sulfur film on a copper surface, in particular to a method for preparing a cobalt-sulfur film on a copper surface based on reverse substitution.

background

The electrolytic reaction of water consists of two half-reactions, the reduction reaction of water, respectively, being called Hydrogen Evolution Reaction (HER) and the oxidation reaction of water, being called Oxygen Evolution Reaction (OER). Under the standard state, the voltage of the reversible electrolytic cell for the water decomposition reaction is 1.23V, but the dynamic obstruction exists in the hydrogen evolution reaction and the oxygen evolution reaction processes, so that the applied voltage required by the practical electrolytic cell is far more than 1.23V. It has been found that the use of noble metal catalytic materials, such as platinum-based catalytic materials, on the electrode surface effectively reduces the overpotential required for the overall water splitting reaction. But their large-scale use is severely hampered by the scarcity and high price of precious metal materials. Therefore, it is of great significance to find suitable non-noble metal catalytic materials to replace noble metal catalytic materials so as to reduce the cost of developing efficient electrolytic water catalytic materials.

The cobalt-sulfur film has excellent electrolytic water catalytic performance, and can be used as a non-noble metal catalytic material for catalyzing electrolytic water decomposition reaction. In recent years, a great deal of research has been focused on a simple method for preparing cobalt-sulfur thin films. Copper is a common electrode material, and a common method for preparing a cobalt-sulfur thin film on the surface of copper is to prepare a pure cobalt thin film on the surface of copper by electroplating or vapor deposition and the like, and then to vulcanize the thin film by using a sulfur-containing atmosphere or a sulfide salt solution to prepare the cobalt-sulfur thin film.

the displacement deposition method has the advantages of simple process, high deposition speed, low cost and the like. However, the standard electrode potential of copper (ECu2+/Cu ═ 0.337V) is significantly higher than that of nickel (ECo2+/Co ═ -0.277V), and thus it is difficult to prepare a cobalt-sulfur thin film on the copper surface by displacement deposition.

disclosure of Invention

The invention provides a method for preparing a cobalt-sulfur film on a copper surface based on reverse replacement, which solves the technical problem of overcoming the defects of complex process and the like of the existing method for preparing the cobalt-sulfur film on the copper surface and aims to reduce the process complexity and the comprehensive cost for preparing the cobalt-sulfur film on the copper surface.

The technical scheme adopted by the invention is as follows:

A method for preparing a cobalt-sulfur film on a copper surface based on reverse substitution is characterized by comprising the following steps:

s1, preparing a reverse displacement sediment liquid: the composition of the reverse displacement deposition solution and the content of each component are as follows: 10-200g/L of cobalt salt and 90-320g/L of additive, and adjusting the pH value of the deposition solution to 3-7 by using dilute sulfuric acid and the like;

s2, copper sample treatment: polishing the copper substrate by using sand paper, removing oxides and pollutants on the surface, then ultrasonically cleaning in an ethanol solution, and drying by using nitrogen;

s3, deposition coating: putting the copper sample into a reverse displacement deposition solution for deposition;

S4, processing a cobalt-sulfur thin film copper sample: and taking out the copper sample, washing the residual deposition solution with deionized water, and drying with nitrogen.

In the step S1, the cobalt salt is one or more of cobalt sulfate, cobalt chloride, and cobalt nitrate.

In the step S1, the additive is one of thiosulfuric acid and thiourea.

In the step S2, 400#, 800#, 1200# sandpaper is used to polish the copper substrate.

In the step S3, the deposition coating conditions are as follows: the temperature of the reverse displacement deposition solution is 20-80 ℃, and the deposition time is 5-60 minutes.

The invention has the beneficial effects that: the method can be used for directly preparing the high-quality cobalt-sulfur film on the copper surface, and has the advantages of simple composition of the deposition solution, less operation process, short time consumption, low cost and the like. The prepared cobalt-sulfur film has excellent electro-catalytic water decomposition performance, and reaches 10mA/cm in 1 mol per liter of potassium hydroxide solution²The required voltage at the oxygen evolution current density of (1.674V) (1.774V is required for the platinum sheet under the same conditions); reaching 40mA/cm²The required voltage for hydrogen evolution current density of (2) was 0.232V (under the same conditions, the required voltage for platinum sheet was 0.237V).

drawings

FIG. 1 is a graph of the stable potentials of cobalt and copper in a reverse displacement deposition solution;

FIG. 2 shows the X-ray diffraction analysis results of the prepared cobalt-sulfur thin film;

FIG. 3 is a polarization curve of oxygen evolution reaction of a cobalt-sulfur thin film on copper, platinum and copper surfaces in 1 mol/L KOH solution;

FIG. 4 is a graph showing the polarization curves of hydrogen evolution reactions of cobalt-sulfur thin films on copper, platinum and copper surfaces in 1 mol/L KOH solution.

Detailed Description

The technical scheme of the invention is further explained by specific embodiments in the following with the accompanying drawings: