The chemical properties of iron oxide Fe3O4 and its application in magnetic materials

Overview of iron oxide Fe3O4

Ferroferric oxide is an inorganic substance with a chemical formula of Fe3O4. It is a magnetic black crystal, so it is also called magnetic iron oxide. It cannot be regarded as "ferrous ferrite" [Fe(FeO2)2], nor can it be regarded as a mixture of ferrous oxide (FeO) and iron oxide (Fe2O3), but it can be regarded as suboxide A compound composed of iron and iron oxide (FeO·Fe2O3). This substance is insoluble in water, alkali solutions, ethanol, ether and other organic solvents. The natural ferroferric oxide is insoluble in acid solution and is easily oxidized to iron oxide (Fe2O3) in the air in a humid state. Usually used as a pigment and polishing agent, it can also be used to make audio tapes and telecommunications equipment.

Nano Fe3O4, the chemical formula is Fe3O4. Usually called black iron oxide, magnetite, black iron oxide, it is a black crystal with magnetism, so it is also called magnetic iron oxide.

Ferroferric oxide has ferromagnetism. If the particle radius is at the nanometer level, it is called ferroferric oxide magnetic particles. As a multifunctional magnetic material, ferroferric oxide magnetic material has been widely used in the fields of tumor treatment, microwave absorbing materials, catalyst carriers, cell separation, magnetic recording materials, magnetic fluids, and medicine.

Three oxides of iron: ferrous oxide (FeO), iron oxide (Fe2O3), and ferric oxide (Fe3O4).

Ferric oxide is the only iron compound that can be magnetized in the middle school stage. Fe2+ and Fe3+ are contained in ferroferric oxide. X-ray diffraction experiments show that ferroferric oxide has a trans-spinel structure, and there is never a ferrite ion FeO22- in the crystal. Ferroferric oxide, the natural mineral type is magnetite. There are two valences of iron in ferroferric oxide. It has a trans-spinel structure, and the oxygen is the most densely packed cube. In addition, Fe3O4 is also a conductor. Because Fe2+ and Fe3+ are basically disorderly arranged at the octahedral position in magnetite, electrons can quickly transfer between the two oxidation states of iron, so Fe3O4 Iron solids have excellent electrical conductivity. Fe3O4 can be regarded as FeO·Fe2O3. This way of writing better shows that Fe3O4 contains Fe(Ⅱ) and Fe(Ⅲ).

Chemical nature

Combustion of iron wire in oxygen will generate ferroferric oxide. Comparing the standard moles of iron oxides to generate Gibbs free energy, it is concluded that Fe3O4 has the greatest thermodynamic stability, so the product is Fe3O4.

Iron and air will form oxides on its surface. At this time, the chemical composition of the oxide film itself is not uniform. For example, a piece of low-carbon steel can be covered by three kinds of oxide films: FeO is in contact with the metal, Fe2O3 is on the side in contact with air, and Fe3O4 is in the middle. More precisely, perhaps a mixture of saturated solid solutions of three oxides constitutes the oxide film on the surface of the steel.

At the same time, the thickness of the oxide film also varies depending on different environmental conditions during oxidation. At room temperature, the thickness of the oxide on the relatively pure iron in dry air does not exceed 20 angstroms (1 angstrom = 0.1 nanometers), but the thickness of the oxide film in humid air increases significantly, and rust spots on the surface can be seen. At this time, the oxide deposition is layered. The side close to the metal is a dense amorphous anhydrous layer, and the side close to the air is a thick porous hydration layer.

Iron reacts with water vapor to produce Fe3O4 and hydrogen.

Fe3O4 has anti-corrosion effect. For example, the bluing of steel parts (also known as blue-burning and baking blue) is to use the oxidation effect of alkaline oxidizing solution to form a blue-black or dark blue Fe3O4 film on the surface of steel parts. Used to increase corrosion resistance, gloss and aesthetics.

Application of iron oxide Fe3O4

Iron oxide Fe3O4 powder is ferromagnetic. If the radius of the formed particles is in the nanometer range, they are called ferromagnetic particles.

1. It can produce magnetic recording materials, high gradient magnetic separators, wave absorbing materials, and special coatings.

2. It is widely used as a carrier of various pharmaceutical ingredients to form a magnetic targeted drug delivery system; used for the separation of magnetic immune cells and nuclear magnetic resonance imaging.

3. Used for precision instruments, gas sealing, vacuum sealing, etc.

Iron oxide Fe3O4 price

The price of iron oxide Fe3O4 powder will vary randomly with factors such as production cost, transportation cost, international situation, and market supply and demand of iron oxide Fe3O4 powder. Tanki New Materials Co., Ltd. aims to help various industries and chemical wholesalers find high-quality, low-cost nanomaterials and chemicals by providing a full set of customized services. If you are looking for iron oxide Fe3O4 powder, please feel free to send an inquiry to get the latest price Fe3O4 iron oxide powder

Iron oxide Fe3O4 supplier

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