Tellurium metal

Tellurium metal powder is a kind of quasi-metallic powder material with grey appearance, density of 6.25g/cm³, melting point of 452°C, boiling point of 1390°C, chemically active, with a certain degree of toxicity, and has a wide range of applications in semiconductors, metallurgy, chemical industry and other fields.

Characteristics

Chemical formula: Te, consisting of a single tellurium atom. Tellurium is chemically similar to sulphur and selenium, is somewhat amphoteric, and its behaviour as an anion or cation depends on the medium.

Chemical stability: Tellurium metal is relatively stable at room temperature, but when heated and melted in air it produces white fumes of tellurium oxide. Moist precipitated tellurium oxidises at 100°C. It is compatible with nitric acid and aqua regia. It reacts with nitric acid, aqua regia, potassium cyanide, potassium hydroxide and sulphuric acid and is insoluble in hot water, cold water and hydrochloric acid.

Appearance: usually grey-black or dark grey powder.

Density: about 6.24 g/cm3.

Melting point: 449.5°C

Boiling point: 1390°C

Electrical conductivity: As a quasi-metal, it has good electrical conductivity, but it is weaker than typical metals.
Thermal conductivity: The thermal conductivity is about 2.35 W/m/K.

Applications

Semiconductor field:

Used to prepare semiconductor materials such as bismuth telluride, which have important applications in temperature difference power generation and refrigeration. Bismuth telluride-based thermoelectric materials can directly convert thermal energy into electrical energy, which has application potential in some special energy utilisation scenarios, such as industrial waste heat recovery and space probes, etc. They are also ideal substitutes for HCFC substances originally used in human refrigeration industry, and can be used to manufacture environmentally friendly refrigeration devices.

It is an important raw material for the preparation of infrared detectors, solar cells and other optoelectronic devices. In infrared detectors, the properties of Tellurium metal elements enable it to respond to infrared radiation of specific wavelengths, thus realising the detection of target objects; in solar cells, Tellurium can be used as an additive or component to improve the photoelectric conversion efficiency of the cells.

Chemical industry:

Used as an additive to catalysts or as the catalyst itself, e.g. as a catalyst in processes such as petroleum cracking and hydrogenation of coal, it can improve the efficiency and selectivity of reactions, reduce conditions such as temperature and pressure of reactions, and save energy and costs.
As a dispersant in the rubber industry, it can increase the strength and elasticity of rubber, improve the processing and physical properties of rubber, and make rubber products more durable and reliable.

It can be added to certain materials to prevent their oxidation, such as preventing the oxidation of polymethylsiloxane and prolonging the service life of the materials.

Metallurgical industry:

In the iron and steel industry, Tellurium metal powder can be used for desulphurisation and deoxidation of steel, reducing the sulphur and oxygen content in steel and improving the quality and properties of steel.

As an additive to alloys, it can improve the strength, hardness, elastic limit, wear resistance and corrosion resistance of alloys, etc. For example, tellurium is added in the production of some special alloy steels, stainless steel welding rods, and high-alloy steels.

Other fields:

Tellurium metal is used as a colouring agent for ceramics and glass, which can make ceramics and glass present specific colours and shades, increasing their decorative and artistic values.

In the foundry industry, Tellurium metal is used to make casting paints to improve the surface quality and moulding of castings.

Tellurium metal is used for printing lead lettering on the pole plates of batteries.