Lanthanide Contraction as a Design Factor for High-Performance Half-Heusler Thermoelectric Materials.

Forming solid solutions, as an effective strategy to improve thermoelectric performance, has a dilemma that alloy scattering will reduce both the thermal conductivity and carrier mobility. Here, an intuitive way is proposed to decouple the opposite effects, that is, using lanthanide contraction as a design factor to select alloying atoms with large mass fluctuation but small radius difference from the host atoms. Typical half-Heusler alloys, n-type (Zr,Hf)NiSn and p-type (Nb,Ta)FeSb solid solutions, are taken as paradigms to attest the validity of this design strategy, which exhibit greatly suppressed lattice thermal conductivity and maintained carrier mobility.

Anisotropic thermoelectric properties of layered compound SnSe.

Similar to high performance SnSe thermoelectrics, SnSe is also a layered structured semiconductor. However, its anisotropic thermoelectric properties are less experimentally investigated. In this work, Cl-doped SnSe bulk materials are successfully prepared, and their thermal stability and anisotropic transport properties are systematically studied.

Compromise and Synergy in High-Efficiency Thermoelectric Materials.

The past two decades have witnessed the rapid growth of thermoelectric (TE) research. Novel concepts and paradigms are described here that have emerged, targeting superior TE materials and higher TE performance. These superior aspects include band convergence, "phonon-glass electron-crystal", multiscale phonon scattering, resonant states, anharmonicity, etc.

Structure, Magnetism, and Thermoelectric Properties of Magnesium-Containing Antimonide Zintl Phases SrMgSb and EuMgSb.

New Mg-containing antimonide Zintl phases, SrMgSb and EuMgSb, were synthesized from high-temperature solid-state reactions in Ta tubes at 1323 K. Their structures can be viewed as derived from the CaAlSb structure type, which adopt the tetragonal space group I4/acd (No. 142, Z = 8) with the cell parameters of a = 17.

Enhancing the Figure of Merit of Heavy-Band Thermoelectric Materials Through Hierarchical Phonon Scattering.

is suggested as an effective strategy to enhance the figure of merit of heavy-band thermoelectric materials. Heavy-band FeNbSb half-Heusler system with intrinsically low carrier mean free path is demonstrated as a paradigm. An enhanced of 1.

Realizing high figure of merit in heavy-band p-type half-Heusler thermoelectric materials.

Solid-state thermoelectric technology offers a promising solution for converting waste heat to useful electrical power. Both high operating temperature and high figure of merit zT are desirable for high-efficiency thermoelectric power generation. Here we report a high zT of ∼1.

The intrinsic disorder related alloy scattering in ZrNiSn half-Heusler thermoelectric materials.

The intrinsic structural disorder dramatically affects the thermal and electronic transport in semiconductors. Although normally considered an ordered compound, the half-Heusler ZrNiSn displays many transport characteristics of a disordered alloy. Similar to the (Zr,Hf)NiSn based solid solutions, the unsubstituted ZrNiSn compound also exhibits charge transport dominated by alloy scattering, as demonstrated in this work.