Tellurium – Properties and Applications

Tellurium is a metalloid element with the chemical symbol Te and atomic number 52. It is used primarily in iron, copper and lead alloys in and around the machining processes. When added to stainless steel and copper it makes those the resultant alloy more machinable. It also adds strength and durability when added to lead and limits its typical corrosive action. Although the main use for tellurium has been constant for the last 40 years or more (see below), science has created some new uses for an old element as well.

Chemical Information

Name : Tellurium
Symbol: Te
Atomic Number: 52
Atomic Mass: 127.6 amu
Melting Point: 449.5 °C (722.65 K, 841.1 °F)
Boiling Point: 989.8 °C (1262.95 K, 1813.64 °F)
Number of Protons/Electrons: 52
Number of Neutrons: 76
Classification: Metalloid
Crystal Structure: Hexagonal
Density @ 293 K: 6.24 g/cm3
Color: silverish

Isotopes

Applications

Steel Industry

For the last 40 or more years the main use for Tellurium is in the steel manufacturing industry. Upwards of 50% (source:USGS) or more of the end-use of Tellurium is still used as an alloying agent with iron and steel. The addition of approximately 0.04% Tellurium to steel improves Fabrication properties such bending, cutting, shaping, and turning.

Photovoltaics

The National Renewable Energy Laboratory (NREL), located in Golden Colorado and a government-owned and contractor-operated facility, has tested Tellurium (used in cadmium telluride) for use in solar panels. Cadmium Telluride (CdTe) achieved some of the highest efficiencies for solar cell electric power generation. In fact, cadmium telluride is the first and only thin film photovoltaic technology to surpass crystalline silicon PV in cost effectiveness primarily in multi-kilowatt systems.

Other Applications

Other uses for Tellurium include:

• Being the preferred precursor for achieving low-temperature growth of CdHgTe by MOVPE (metalorganic vapour phase epitaxy) which in turn is a major process in the manufacture of optoelectonics
• Tellurium as a tellurium suboxide is used in the media later of several types of rewritable optical discs including CD-RW, DVD-RW and rewritable blu-ray discs.

The Future of Tellurium

While the vast quantities of Tellurium have been used in the production of metals such as steel, it is likely that this will remain the main use into the near future. As the efficiencies of solar cells improve with more research, the business case for solar cells becomes stronger along with government mandates for clean energy. Lower cost and government regulations should open up the possibilities and make it easier to develop business cases for using solar energy over the next decade thereby increasing the need for Tellurium in that industry as well.

This information has been sourced, reviewed and adapted from materials provided by AHP Materials.

For more information o this source, please visit AHP Materials.