Lead telluride

Lead telluride

Names
Other names Lead(II) telluride Altaite
Identifiers
CAS Number	1314-91-6 Y
ECHA InfoCard	100.013.862
PubChem CID	4389803
Properties
Chemical formula	PbTe
Molar mass	334.80 g/mol
Appearance	gray cubic crystals.
Density	8.164 g/cm3
Melting point	924 °C (1,695 °F; 1,197 K)
Solubility in water	insoluble
Band gap	0.25 eV (0 K) 0.32 eV (300 K)
Electron mobility	1600 cm2 V−1 s−1 (0 K) 6000 cm2 V−1 s−1 (300 K)
Structure
Crystal structure	Halite (cubic), cF8
Space group	Fm3m, No. 225
Lattice constant	a = 6.46 Angstroms
Coordination geometry	Octahedral (Pb2+) Octahedral (Te2−)
Thermochemistry
Std molar entropy (So298)	50.5 J·mol−1·K−1
Std enthalpy of formation (ΔfHo298)	-70.7 kJ·mol−1
Std enthalpy of combustion (ΔcHo298)	110.0 J·mol−1·K−1
Hazards
Safety data sheet	External MSDS
EU classification (DSD)	Repr. Cat. 1/3 Harmful (Xn) Dangerous for the environment (N)
R-phrases	R61, R20/22, R33, R62, R50/53
S-phrases	S53, S45, S60, S61
Flash point	Non-flammable
Related compounds
Other anions	Lead(II) oxide Lead(II) sulfide Lead selenide
Other cations	Carbon monotelluride Silicon monotelluride Germanium telluride Tin telluride
Related compounds	Thallium telluride Bismuth telluride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Lead telluride is a compound of lead and tellurium (PbTe). It crystallizes in the NaCl crystal structure with Pb atoms occupying the cation and Te forming the anionic lattice. It is a narrow gap semiconductor with a band gap of 0.32 eV. It occurs naturally as the mineral altaite.

PbTe has proven to be a very important intermediate thermoelectric material. The performance of thermoelectric materials can be evaluated by the figure of merit, ${\displaystyle ZT=S^{2}\sigma T/\kappa }$, in which ${\displaystyle S}$ is the Seebeck coefficient, ${\displaystyle \sigma }$ is the electrical conductivity and ${\displaystyle \kappa }$ is the thermal conductivity. In order to improve the thermoelectric performance of materials, the power factor (${\displaystyle S^{2}\sigma }$) needs to be maximized and the thermal conductivity needs to be minimized.