Selenium (/sɨˈliːniəm/ sə-LEE-nee-əm) is a chemical element with atomic number 34, chemical symbol Se, and an atomic mass of 78.96. It is a nonmetal, whose properties are intermediate between those of adjacent chalcogen elements sulfur and tellurium. It rarely occurs in its elemental state in nature, but instead is obtained as a side-product in the refining of other elements.
Selenium is found in sulfide ores such as pyrite, where it partially re...
More
Selenium (/sɨˈliːniəm/ sə-LEE-nee-əm) is a chemical element with atomic number 34, chemical symbol Se, and an atomic mass of 78.96. It is a nonmetal, whose properties are intermediate between those of adjacent chalcogen elements sulfur and tellurium. It rarely occurs in its elemental state in nature, but instead is obtained as a side-product in the refining of other elements.
Selenium is found in sulfide ores such as pyrite, where it partially replaces the sulfur. Minerals that are selenide or selenate compounds are also known, but are rare. The chief commercial uses for selenium today are in glassmaking and in pigments. Uses in electronics, once important, have been supplanted by silicon semiconductor devices. It is a semiconductor with the unusual property of conducting electricity better in the light than in the dark, and is used in photocells. It has recently seen a resurgence in use in the synthesis of fluorescent quantum dots. Where it is commonly used in conjunction with...
Less
