Localized vibration and avoided crossing in SrTi11O20 for oxide thermoelectrics with intrinsically low thermal conductivity

Many state-of-the-art thermoelectric alloys achieve phonon glass and electron crystal (PGEC) via chemical bonding hierarchy (CBH), which can provide a rigid network for electron conduction pathway and loosely bonded atoms...

Anharmonic phonon frequency and ultralow lattice thermal conductivity in β-Cu2Se liquid-like thermoelectrics

The prototype phonon-liquid electron-crystal β-Cu2Se has been ranked among the best thermoelectric material with its ultralow lattice thermal conductivity (κL).

Zintl-phase Eu2ZnSb2: A promising thermoelectric material with ultralow thermal conductivity

Zintl compounds are considered to be potential thermoelectric materials due to their “phonon glass electron crystal” (PGEC) structure. A promising Zintl-phase thermoelectric material, 2-1-2–type Eu2ZnSb2 (P63/mmc), was prepared and investigated. The extremely low lattice thermal conductivity is attributed to the external Eu atomic layers inserted in the [Zn2Sb2]2- network in the structure of 1-2-2–type EuZn2Sb2(P3¯m1), as well as the abundant inversion domain boundary. By regulating the Zn deficiency, the electrical properties are significantly enhanced, and the maximum ZT value reaches ∼1.0 at 823 K for Eu2Zn0.98Sb2. Our discovery provides a class of Zintl thermoelectric materials applicable in the medium-temperature range.