New promising bulk thermoelectrics: intermetallics, pnictides and chalcogenides

摘要: The need of alternative “green” energy sources has recently renewed the interest in thermoelectric (TE) materials, which can directly convert heat to electricity or, conversely, electric current cooling. performance a material be estimated by so-called figure merit, zT = σ α 2 T/λ (α Seebeck coefficient, σ 2 power factor, σ and λ electrical thermal conductivity, respectively), that depends only on material. In middle 1990s “phonon glass electron crystal” concept was developed, which, together with better understanding parameters affect zT use new synthesis methods characterization techniques, led discovery improved bulk materials start being implemented applications. During last decades, special focus been made skutterudites, clathrates, half-Heusler alloys, Si1−x Ge x-, Bi2Te3- PbTe-based materials. However, many other particular based intermetallics, pnictides, chalcogenides, oxides, etc. are now emerging as potential advanced thermoelectrics. Herein we discuss this field, emphasis strategies reduce lattice part conductivity maximize review those pnictides chalcogenides. A final chapter, discussing different shaping techniques leading (eventually from nanostructured TE materials), is also included.