Topics Covered
Description
Applications
Chemical Properties
Electrical Properties
Thermal, Mechanical and Optical Properties
Safety Information
Description
Selenium is a member of the sulfur group of nonmetallic elements. It exists in several allotropic forms: the most common forms are a red crystalline material/powder and a gray crystalline metal-like form known as metallic selenium.
It exhibits photovoltaic and photoconductive activity. It was discovered by Jöns Jakob Berzelius in 1817. Selenium was named after the Greek word "Selene", which means moon.
Applications
Selenium finds applications in the following:
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Solar cells and photoconductor applications
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Manganese electrolysis
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Alloys and glass production
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Modification of vulcanization catalysts used in rubber production
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DC power surge protection
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Fabrication of quantum dots
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Toning of photographic prints
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X-ray crystallography.
Chemical Properties
The chemical properties of selenium are provided in the table below:
Chemical Properties |
Chemical Formula |
Se |
Molecular Weight |
78.96 |
CAS No. |
7782-49-2 |
Group |
16 |
Crystal Structure |
Hexagonal |
Lattice Constant |
4.360 Å |
Electrical Properties
The electrical properties of selenium are provided in the table below:
Electrical Properties |
Critical Superconducting Temperature |
6.75-6.95 K |
Dielectric Constant |
6.6 |
Band Gap |
1.5 eV |
Hole Mobility |
5 cm2/Vs |
Thermal, Mechanical and Optical Properties
The thermal, mechanical and optical properties of selenium are provided in the tables below:
Thermal Properties |
Heat of Fusion |
84 J/g |
Heat of Vaporization |
3140 J/g |
Thermal Expansion Coefficient |
37µm/m°C |
Specific Heat Capacity |
0.2926 J/g°C |
Thermal Conductivity |
1.31 W/mK |
Melting Point |
220°C |
Mechanical Properties |
Modulus of Elasticity |
57.9 GPa |
Shear Modulus |
6.46 GPa |
Optical Properties |
Refractive Index |
2.5 |
Safety Information
Safety Information |
GHS Hazard Statements |
H331 - Toxic if inhaled.
H301 - Toxic if swallowed
H373 - May cause damage to organs through prolonged or repeated exposure
H413 - May cause long lasting harmful effects to aquatic life |
Safety Precautions |
P261- Avoid breathing dust, gas, fume, vapors, spray, mist.
P264 - Wash exposed skin thoroughly after handling.
P270 - Do no eat, drink or smoke when using this product.
P273 - Avoid release to the environment. |