Among the most widely used applications of electrolysis is the addition of layers of one metal to another, through the electrochemical process known as electroplating. Corrosion protection is one of the main reasons why small layers of one metal are applied to another, as many metals are susceptible to oxidation from contact with the air and moisture found in the environment. In this article, we will look at how to apply a copper layer to metal, one of the most widespread corrosion protection techniques in the world.
- A 9-volt battery or an external power source.
- A metal object.
- One container.
- Cables and crocodile connectors.
- Copper sulphate.
Applying a copper layer to a metal object using electrolysis is a simple process. In order to do this, we need to set up an assembly so that the electrolysis reaction can proceed smoothly.
We start by thoroughly washing the container with water and detergent, then rinse until all detergent residue is removed, making sure that the container is completely clean, as any impurities can contaminate our electroplating process.
Then, with the container completely clean, dissolve a teaspoonful or a little more of copper sulphate in it, until a homogeneous blue solution is obtained. The intensity of the solution will depend on the amount of copper ions in the aqueous solution.
Once the copper sulphate solution has been made, it is time to make the electrical connections to encourage the movement of copper ions. To do this, we connect the negative pole of the battery to the metal object we are going to use (anode) and the positive pole, we leave it in contact with the aqueous solution of copper sulphate. We introduce the metal object into the container and wait for about 30 minutes.
When the metal object is removed, a light layer of copper can be seen on top of it, creating a protective layer against corrosion. To improve the experience, we can use different types of substances, such as silver nitrate and different metals, taking into account their oxidation potential, which must be higher than that of the substance, so that the protection can be achieved by electroplating.
How it works
When the electric current is applied, the copper ions will migrate towards the anode (negatively charged metal object), adding to the anode and forming a copper plate that will thicken as the minutes pass.