Ultralow
Lattice Thermal Conductivity and Thermoelectric
Properties of Monolayer Tl<sub>2</sub>O
SajjadMuhammad
SinghNirpendra
SattarShahid
WolfStefaan De
SchwingenschlöglUdo
2019
We report first-principles
results on the thermal and thermoelectric
properties of monolayer Tl<sub>2</sub>O. The lattice thermal conductivity
and electronic transport coefficients are obtained by semiclassical
Boltzmann transport theory. Monolayer Tl<sub>2</sub>O is found to
be a semiconductor with a direct band gap of 1.62 eV. The lattice
thermal conductivity turns out to be ultralow, for example, 0.17 W/mK
at 300 K. Combined with a high power factor, this results in excellent
thermoelectric performance. For example, at 500 K the p-type and n-type
thermoelectric figures of merit reach peak values of 0.96 and 0.94
at hole and electron concentrations of 1.2 × 10<sup>11</sup> and
0.8 × 10<sup>11</sup> cm<sup>–2</sup>, respectively.