Sr(Ag Li ) Se and [Sr Se ][(Ag Li ) Se ] Tunable Direct Band Gap Semiconductors.

Synthesizing solids in molten fluxes enables the rapid diffusion of soluble species at temperatures lower than in solid-state reactions, leading to crystal formation of kinetically stable compounds. In this study, we demonstrate the effectiveness of mixed hydroxide and halide fluxes in synthesizing complex Sr/Ag/Se in mixed LiOH/LiCl. We have accessed a series of two-dimensional Sr(Ag Li ) Se layered phases.

Contrasting role of antimony and bismuth dopants on the thermoelectric performance of lead selenide.

Increasing the conversion efficiency of thermoelectric materials is a key scientific driver behind a worldwide effort to enable heat to electricity power generation at competitive cost. Here we report an increased performance for antimony-doped lead selenide with a thermoelectric figure of merit of ~1.5 at 800 K.

High-performance tellurium-free thermoelectrics: all-scale hierarchical structuring of p-type PbSe-MSe systems (M = Ca, Sr, Ba).

We present a systematic study of the characterization and thermoelectric properties of nanostructured Na-doped PbSe embedded with 1-4% MSe (M = Ca, Sr, Ba) phases as endotaxial inclusions. The samples were powder-processed by the spark plasma sintering technique, which introduces mesoscale-structured grains. The hierarchical architectures on the atomic scale (Na and M solid solution), nanoscale (MSe nanoprecipitates), and mesoscale (grains) were confirmed by transmission electron microscopy.

High performance thermoelectrics from earth-abundant materials: enhanced figure of merit in PbS by second phase nanostructures.

Lead sulfide, a compound consisting of elements with high natural abundance, can be converted into an excellent thermoelectric material. We report extensive doping studies, which show that the power factor maximum for pure n-type PbS can be raised substantially to ~12 μW cm(-1) K(-2) at >723 K using 1.0 mol % PbCl(2) as the electron donor dopant.

Thermoelectrics from abundant chemical elements: high-performance nanostructured PbSe-PbS.

We report promising thermoelectric properties of the rock salt PbSe-PbS system which consists of chemical elements with high natural abundance. Doping with PbCl(2), excess Pb, and Bi gives n-type behavior without significantly perturbing the cation sublattice. Thus, despite the great extent of dissolution of PbS in PbSe, the transport properties in this system, such as carrier mobilities and power factors, are remarkably similar to those of pristine n-type PbSe in fractions as high as 16%.

Structural diversity by mixing chalcogen atoms in the chalcophosphate system K/In/P/Q (Q = S, Se).

The new thiophosphate salt K(4)In(2)(PS(4))(2)(P(2)S(6)) (1), the selenophosphate salts K(5)In(3)(mu(3)-Se)(P(2)Se(6))(3) (2), K(4)In(4)(mu-Se)(2)(P(2)Se(6))(3) (3), and the mixed seleno-/thiophosphate salt K(4)In(4)(mu-Se)(P(2)S(2.36)Se(3.64))(3) (4) are described.

A new chalcogenide homologous series A2[M(5+n)Se(9+n)] (A = Rb, Cs; M = Bi, Ag, Cd).

The ternary and quaternary selenides, beta-CsBi3Se5, Rb2CdBi6Se11, CsAg(0.5)Bi(3.5)Se6, CsCdBi3Se6, Rb2Ag(1.

A new thermoelectric material: CsBi4Te6.

The highly anisotropic material CsBi(4)Te(6) was prepared by the reaction of Cs/Bi(2)Te(3) around 600 degrees C. The compound crystallizes in the monoclinic space group C2/m with a = 51.9205(8) A, b = 4.

CsMBi(3)Te(6) and CsM(2)Bi(3)Te(7) (M = Pb, Sn): new thermoelectric compounds with low-dimensional structures.

The new materials CsPbBi(3)Te(6) and CsPb(2)Bi(3)Te(7) were discovered through reactions of CsBi(4)Te(6) with PbTe, whereas the isostructural materials CsSnBi(3)Te(6) and CsSn(2)Bi(3)Te(7) were discovered through corresponding reactions with SnTe. The compounds can also be prepared from stoichiometric mixtures of Cs(2)Te, Pb (Sn), Bi, and Te. The crystal structures show a layered architecture of NaCl-type slabs alternating with layers of Cs atoms.