Overview

Sodium telluride is an inorganic compound with the nominal formula Na2Te. It is composed of sodium cations and the telluride anion (Te2−) and serves as a convenient laboratory source of tellurium(II) anions. For general reference see Sodium telluride. Background information on the metal component appears at sodium and on the anionic chemistry at telluride ion.

Characteristics and structure

Compounds of the type M2X (alkali metal chalcogenides) commonly adopt the antifluorite crystal motif, in which larger chalcogenide ions form a cubic close-packed array and smaller alkali cations occupy tetrahedral sites. Sodium telluride behaves as a strong two-electron donor (reducing agent) in both inorganic and organic reactions. It is sensitive to oxygen and moisture and may darken or decompose on exposure.

Preparation and reactivity

In practice, Na2Te is prepared by direct combination of elemental tellurium with sodium or by reduction of tellurium using sodium dispersions or solvated electrons in inert solvents. It reacts readily with water and acids; hydrolysis can liberate hydrogen telluride (H2Te), a toxic gas, so work is normally conducted under inert atmosphere. It is also prone to oxidation to polyselenide- or polytelluride-type species on exposure to air.

Uses and examples

  • As a reagent in organic synthesis to introduce tellurium into molecules or to prepare organotellurium compounds.
  • As a precursor in the synthesis of metal tellurides and semiconductor materials in research settings.
  • In laboratory research where a soluble or dispersible source of Te2− is required for further transformations.

Handling and safety

Sodium telluride must be handled under inert gas and stored dry. It is incompatible with acids and oxidizers; accidental contact with moisture or acid may generate H2Te, which is highly toxic and has a foul odor. Consult material safety resources for precautions and first-aid measures; additional safety information can be found at safety and supplier pages.

Related compounds include other alkali metal tellurides (e.g., potassium telluride) and the lighter chalcogen analogs such as sodium sulfide and sodium selenide, which share similar structural motifs but differ in reactivity and toxicity.