Correction: Eu-Eu valence transition in double, Eu-, and Na-doped PbSe from transport, magnetic, and electronic structure studies.

Correction for 'Eu-Eu valence transition in double, Eu-, and Na-doped PbSe from transport, magnetic, and electronic structure studies' by Bartlomiej Wiendlocha et al., Phys. Chem.

Eu-Eu valence transition in double, Eu-, and Na-doped PbSe from transport, magnetic, and electronic structure studies.

The Eu atoms in PbEuSe have long been assumed to be divalent. We show that p-type doping of this magnetic semiconductor alloy with Na can modify the effective Eu valence: a mixed, Eu-Eu state appears in PbEuNaSe at particular values of y. Magnetization, carrier concentration, resistivity, and thermopower of PbEuNaSe are reported for a number of samples with different x and y.

Solvothermal Synthesis of Tetrahedrite: Speeding Up the Process of Thermoelectric Material Generation.

Derivatives of synthetic tetrahedrite, Cu12Sb4S13, are receiving increasing attention in the thermoelectric community due to their exploitation of plentiful, relatively nontoxic elements, combined with a thermoelectric performance that rivals that of PbTe-based compounds. However, traditional synthetic methods require weeks of annealing at high temperatures (450-600 °C) and periodic regrinding of the samples. Here we report a solvothermal method to produce tetrahedrite that requires only 1 day of heating at a relatively low temperature (155 °C).

Highly efficient (In₂Te₃)x(GeTe)(3-3x) thermoelectric materials: a substitute for TAGS.

GeTe is a versatile base compound to produce highly efficient p-type thermoelectric materials such as the TAGS materials (AgSbTe2)1-x(GeTe)x and GeTe-PbTe nanocomposites. The pure GeTe composition shows a very high power factor, ~42 μW cm(-1) K(-2), between 673 K and 823 K, which is among the highest power factors that have ever been reported in this temperature range. However, its relatively high thermal conductivity limits the dimensionless figure of merit ZT to values of only unity.

Natural mineral tetrahedrite as a direct source of thermoelectric materials.

We show that a simple powder processing procedure using natural mineral tetrahedrite, the most widespread sulfosalt on earth, provides a low cost, high throughput means of producing thermoelectric materials with high conversion efficiency. These earth-abundant thermoelectrics can open the door to many new and inexpensive power generation opportunities.

Role of lone-pair electrons in producing minimum thermal conductivity in nitrogen-group chalcogenide compounds.

Fully dense crystalline solids with extremely low lattice thermal conductivity (κ(L)) are of practical importance for applications including thermoelectric energy conversion and thermal barrier coatings. Here we show that lone-pair electrons can give rise to minimum κ(L) in chalcogenide compounds that contain a nominally trivalent group VA element. Electrostatic repulsion between the lone-pair electrons and neighboring chalcogen ions creates anharmonicity in the lattice, the strength of which is determined by the morphology of the lone-pair orbital and the coordination number of the group VA atom.

Resistance, magnetoresistance, and thermopower of zinc nanowire composites.

We report a very large enhancement of the thermopower of 4 nm diameter metallic Zn nanowires, with a temperature dependence that is consistent with that of their electrical resistivity and the Mott formula. The temperature dependence of the resistance, magnetoresistance, and thermopower of composites consisting of 15, 9, and 4 nm diameter Zn nanowires imbedded in porous host materials is reported. The 15 nm wires are metallic.

Thermoelectric power of bismuth nanocomposites.

Because of the increase in the electronic density of states in low-dimensional systems, semiconductor quantum wires constitute a most promising thermoelectric material. We report here the first experimental observation of a very large enhancement of the thermoelectric power of composites containing bismuth nanowires with diameters of 9 and 15 nm, embedded in porous alumina and porous silica. The temperature dependence of the electrical resistance shows that the samples are semiconductors with energy gaps between 0.