Title: Lead Telluride
CAS Registry Number: 1314-91-6
Molecular Formula: PbTe
Molecular Weight: 334.80
Percent Composition: Pb 61.89%, Te 38.11%
Literature References: Found in nature as the mineral altaite. Prepd from lead nitrate, sodium carbonate and powdered tellurium: Montignie, Bull. Soc. Chim. Fr. 1947, 750. Prepn of single crystals by heating stoichiometric quantities of the elements in a graphite cup or fused quartz tube: Brady, J. Electrochem. Soc. 101, 466 (1954).
Properties: Silver-gray cubic crystals. d420 8.16. mp 905°. Most of the crystal is p-type, the n-type material being present in the surface layer. Energy gap 0.27 ev. Electron mobility 2240 cm2/volt-sec. Hole mobility 860 cm2/volt-sec. Resistivity 0.005 ohm-cm (p-type), 0.00090 ohm-cm (n-type). Not attacked by hydrochloric, hydrofluoric, perchloric and acetic acids or their mixtures; not attacked by solns of 30% potassium hydroxide or of alkali metal sulfides. Dil nitric acid turns the surface black, while concd nitric acid produces lighter gray surface and turns the black surface to gray. Hot concd sulfuric acid produces a reddish-violet surface.
Melting point: mp 905°
Density: d420 8.16
Use: In photoconductor cells; in semiconductor research. |